WO2014148309A1

WO2014148309A1 - Mobile x-ray device and positioning control method

Info

Publication number: WO2014148309A1
Application number: PCT/JP2014/056305
Authority: WO
Inventors: 明小島
Original assignee: 株式会社日立メディコ
Priority date: 2013-03-21
Filing date: 2014-03-11
Publication date: 2014-09-25
Also published as: JPWO2014148309A1; JP6251725B2

Abstract

To facilitate positioning operation that is necessary for X-ray imaging, a mobile X-ray device (1) comprises: an X-ray source (40) which is supported in a raisable and lowerable manner; an ultrasonic distance measurement unit (90) which measures the distance from the X-ray source (40) to an object subject to the distance measurement that is positioned below the X-ray source; and a control unit (12) and a braking unit (80) which compare a focus-image reception face distance that indicates the distance from the X-ray source (40) to an X-ray detector (4) and a measurement value obtained by measurement by the ultrasonic distance measurement unit (90) and on the basis of the result of comparison apply braking to the raising and lowering movement.

Description

Mobile X-ray apparatus and positioning control method thereof

The present invention relates to a mobile X-ray apparatus and a positioning control method thereof, and more particularly to a technique for facilitating positioning during imaging of a mobile X-ray apparatus that moves inside a facility and performs X-ray imaging.

Patent Document 1 includes a main body, a carriage on which the main body is mounted, an X-ray generation unit having an X-ray tube that generates X-rays, an arm that supports the X-ray generation unit, and a support column that supports the arm. A movable X-ray apparatus is disclosed that includes a vertical drive unit that rotates and moves the arm up and down along the support column.

JP 2011-193996

When performing X-ray imaging using a mobile X-ray apparatus as disclosed in Patent Document 1, it is necessary to position the X-ray generation unit at a position facing the detector. Conventionally, while measuring the distance from the X-ray generator to the detector using a measure or ultrasonic distance meter attached near the X-ray generator, the distance between the focal planes (hereinafter referred to as `` SID '') is measured. (SID: Source Image receptor Distance) ”has been finely adjusted many times, and there was a problem that it took time to perform positioning work.

Therefore, an object of the present invention is to provide a technique capable of easily performing a positioning operation necessary for X-ray imaging in a mobile X-ray apparatus.

In order to solve the above problems, the present invention includes an X-ray source supported so as to be movable up and down, and measures a distance from the X-ray source to a distance measurement object located under the X-ray source, A predetermined distance between the focal planes and the distance to the X-ray detector that detects the X-ray source and the X-ray generated from the X-ray source and outputs an X-ray signal indicating the intensity. And a measured value obtained by the measurement are compared, and braking is applied to the up-and-down movement based on the comparison result.

According to the present invention, it is possible to provide a technique capable of easily performing a positioning operation necessary for X-ray imaging in a mobile X-ray apparatus.

Explanatory drawing which shows the whole structure of the mobile X-ray apparatus which concerns on 1st embodiment. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a rail, a brake part, and an arm support part of a mobile X-ray apparatus 1 according to a first embodiment, wherein (a) is a side surface (front side surface) of a column 30 that faces an arm support part 70. (B) shows the AA ′ cross section of (a) (cross section of the gear portion along the axial direction), and (c) shows the BB ′ cross section of (a) (perpendicular to the axial direction). And a cross section of the gear fixed shaft). (a), (b) is explanatory drawing which shows the structure in the support | pillar 30 for energizing the arm support part 70 of 1st embodiment. Explanatory drawing which shows the internal structure regarding the positioning process of the mobile X-ray apparatus 1 which concerns on 1st embodiment. The flowchart which shows the flow of the process of 1st embodiment. (a) And (b) is explanatory drawing which shows the positional relationship of an ultrasonic distance measurement part and distance measurement object. Explanatory drawing which shows the whole structure of the mobile X-ray apparatus which concerns on 2nd embodiment. Explanatory drawing which shows the internal structure regarding the positioning process of the mobile X-ray apparatus 1a which concerns on 2nd embodiment. The flowchart which shows the one aspect | mode of the process flow of the mobile X-ray apparatus 1a which concerns on 2nd embodiment. The flowchart which shows another aspect of the flow of a process of the mobile X-ray apparatus 1a which concerns on 2nd embodiment. Explanatory drawing which shows the internal structure regarding the positioning process of the mobile X-ray apparatus which concerns on 3rd embodiment. The flowchart which shows the one aspect | mode of the process flow of the mobile X-ray apparatus which concerns on 3rd embodiment. Explanatory drawing which shows the internal structure of the mobile X-ray apparatus which concerns on 4th embodiment. The flowchart which shows the flow of a process of the mobile X-ray apparatus which concerns on 4th embodiment. Explanatory drawing which shows the process which searches the positioning position of a horizontal direction

A mobile X-ray apparatus according to the present invention includes a main body, a moving section that causes the main body to travel on the floor, a column that is erected on the moving section, an X-ray source that generates X-rays, An arm that supports the X-ray source, an arm support that supports the arm so as to be movable up and down along the axial direction of the column, a brake that applies braking to the vertical movement of the arm support, and the X A distance measuring unit for measuring a distance from a radiation source to a distance measurement object located under the X-ray source; and an X-ray signal indicating the intensity of the X-ray detected from the X-ray source. A first input unit that receives an input of a distance between focal image receiving surfaces indicating a distance to an X-ray image receiving surface included in the X-ray detector to be output, a measurement value obtained by the measurement, and the distance between the focal image receiving surfaces Compare the distances, and based on the comparison results, And a control unit that performs control for applying a dynamic, and further comprising a.

The mobile X-ray apparatus notifies the direction in which the arm should be moved along the axial direction of the support column in order to bring the measurement value closer to the distance between the focus image receiving surfaces based on the comparison result by the control unit. You may further provide the notification part to do.

The brake portion has a relatively weak braking force, a first brake portion for reducing the speed of the up-and-down movement, and a relatively strong braking force, and the arm support portion extends along the axial direction. A second brake unit for stopping at a predetermined position, and the control unit includes the first brake unit when the distance between the focus image-receiving surfaces and the difference between the measured values are within a predetermined deceleration range. And the second brake unit may be operated when the measured value coincides with the distance difference between the focus image receiving surfaces.

Further, a second input unit that receives input of body thickness information indicating the body thickness of the subject may be further provided. And the said control part may compare the calculated value computed based on the said measured value and the body thickness of the said test object, and the said distance between focus receiving surfaces.

A horizontal brake unit for braking the horizontal movement of the arm configured to move horizontally in a plane orthogonal to the axial direction of the support column may be further provided. The distance measurement unit performs the measurement at each position in the plane that changes due to the horizontal movement, and the control unit detects a minimum value among the measurement values obtained at each position, The horizontal brake portion may be operated at a position in the plane corresponding to the minimum value.

A positioning control method for a mobile X-ray apparatus according to the present invention is a positioning control method for a mobile X-ray apparatus including an X-ray source supported so as to be movable up and down, from the X-ray source to the X-ray source. A step of measuring a distance to a distance measurement object located below, and a predetermined distance between the focal plane and detecting the X-ray source and the X-ray generated from the X-ray source. The distance between the focus image planes indicating the distance to the X-ray detector that outputs the X-ray signal indicating the intensity of the sensor and the measured value obtained by the measurement are compared, and based on the comparison result, Applying braking to the movement.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. Throughout the drawings, the same components are denoted by the same reference numerals, and redundant description is omitted.

<First embodiment>
In the first embodiment, during the positioning, the distance between the X-ray source and the distance measurement object located immediately below is continuously measured, and the calculated value obtained based on the measurement matches a predetermined stop condition. This is an embodiment in which a brake is applied to the lifting and lowering operation of the arm that supports the X-ray source. Hereinafter, the first embodiment will be described with reference to FIGS. FIG. 1 is an explanatory diagram showing the overall configuration of the mobile X-ray apparatus according to the first embodiment.

FIG. 2 is an explanatory view showing a rail, a brake part, and an arm support part of the mobile X-ray apparatus 1 according to the first embodiment, and (a) is a side view of the support column 30 facing the arm support part 70. (Front side surface) showing a state of non-braking, (b) shows an AA ′ cross section of (a) (cross section in the gear portion along the axial direction), (c) is ( a) BB ′ cross section of a) (cross section orthogonal to the axial direction and at the gear fixed shaft), showing a state at the time of braking.

FIGS. 3 (a) and 3 (b) are explanatory views showing a configuration in the support column 30 for biasing the arm support portion 70. FIG. FIG. 4 is an explanatory diagram showing an internal configuration related to the positioning process of the mobile X-ray apparatus 1 according to the first embodiment. FIG. 5 is a flowchart showing a process flow of the first embodiment. FIG. 6 is an explanatory diagram showing the positional relationship between the ultrasonic distance measuring unit and the distance measurement target.

First, the configuration of the mobile X-ray apparatus according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, a mobile X-ray apparatus 1 according to the present embodiment is configured by using a main body 10 and a moving unit that moves the main body 10 mounted thereon (in this embodiment, a moving carriage is used. (Referred to as a `` trolley '') 20, a support column 30 installed on the carriage 20, an X-ray source 40 having an X-ray tube for generating X-rays, and an X-ray movable diaphragm 50 for limiting the X-ray irradiation field , An arm 60 that supports the X-ray source 40, an arm support unit 70 that supports the arm 60 so as to be movable up and down along the axial direction of the support column 30, and a brake unit 80 that brakes the lifting operation of the arm support unit 70 And the distance measuring unit 90 for measuring the distance between the brake release button 85 for releasing the lock of the brake unit 80 (releasing the brake) and the distance measurement object directly under the X-ray source 40 and the X-ray source 40. And comprising.

In the present embodiment, since an ultrasonic distance measuring device is used as the distance measuring unit 90, the distance measuring unit 90 is hereinafter referred to as an ultrasonic distance measuring unit 90. When X-ray imaging is performed by the mobile X-ray apparatus 1, the X-ray detector 4 is placed on the bed 3 and the subject 2 is placed on the X-ray detector 4. The X-ray detector 4 is arranged to face the X-ray source 40 with the subject 2 interposed therebetween. Therefore, the subject 2, the bed 3, and the X-ray detector 4 can correspond to the distance measurement target object.

The X-ray detector 4 includes FPD (Flat Panel Detector) in which a plurality of detection elements for detecting X-rays are arranged in a two-dimensional array, as well as an imaging plate that accumulates films and transmitted X-rays as latent images. Any type. When using an FPD as the X-ray detector 4, the control unit 12 also has an image processing unit, electrically connects the control unit 12 and the X-ray detector 4, and an X-ray signal indicating the intensity of transmitted X-rays May be integrated with the mobile X-ray apparatus 1 so as to generate an X-ray absorption distribution image of the subject based on the X-ray signal. Further, when a film and an imaging plate are used as the X-ray detector 4, it may be configured separately from the mobile X-ray apparatus 1.

The main body unit 10 of the mobile X-ray apparatus 1 includes an operation panel 11 for setting imaging conditions, and a control unit 12 that performs control related to a positioning process and a process for generating X-rays according to the imaging conditions described later. Prepare.

The bogie 20 includes a wheel 21 and a self-propelled caster 22 that are driven on a floor by a motor.

The support column 30 is rotatably supported on the carriage 20 so that the axial direction of the support column 30 coincides with the rotation axis direction. Further, on the side surface (hereinafter referred to as “front side surface”) of the support column 30 facing the arm support portion 70, a groove portion 31 along the axial direction opening toward the arm support portion 70 and a flat plate fixed in the groove portion 31. And a rail 32 cut into a rod-like bar.

The arm support portion 70 can move up and down along the rail 32 in the support column 30. A gear portion 71 is disposed in the arm support portion 70 as will be described in detail later, and the arm support portion 70 can move up and down along the rail 32 by engaging the gear portion 71 with the rail 32. At this time, as shown in FIGS. 3 (a) and 3 (b), the arm support portion 70 is urged vertically upward in the support column 30 so that an external force is not applied to the arm 60 and the X-ray source 40. A mechanism is provided that keeps the position of the portion 70 in the vertical direction at the current position. Thus, the operator can move the arm 60 upward by applying a small upward force to the arm 60 and can slowly move the arm 60 downward by applying a small force downward. .

Specifically, as shown in FIG. 3 (a), in the support column 30, a spring 201 having one end fixed to the support column 30, a moving pulley 204 fixed to the other end of the spring 201, and fixed

pulleys

202, 203 are provided. And are arranged. The fixed pulley 202 includes a small-diameter pulley 202a and a large-diameter pulley 202b that are coaxially fixed, and the fixed pulley 203 includes a small-diameter pulley 203a and a large-diameter pulley 203b that are coaxially fixed.

One end of the first wire 205 is fixed to the arm support portion 70, and the other end of the first wire 205 is wound around the large-diameter pulley 202b of the fixed pulley 202. Both ends of the second wire 206 are wound around the small-diameter pulley 202a of the fixed pulley 202 and the large-diameter pulley 203b of the fixed pulley 203, respectively. One end of a third wire 207 is wound around the small-diameter pulley 203a of the fixed pulley 203. The third wire 207 passes through the movable pulley 204, and a weight 208 is fixed to the other end. As a result, the direction of the force of the spring 201 is changed by the fixed

pulleys

202 and 203, and the first wire 205 is added to the arm support unit 70 as a vertically upward force to support the gravity applied to the arm support unit 70. The 70 position can be kept at the current position. Further, the fixed

pulleys

202 and 203 wind up and feed out the first to third wires 205 to 207 so that the arm support portion 70 can be moved at any height in the column 30. Can be supported. The spring 201 is designed with a spring constant so as to generate a spring force that balances the weight of the arm support 70, the arm 60, and the X-ray source 40.

Further, as shown in FIG. 3 (b), a fixed pulley 201 can be attached to the uppermost portion of the support column 30, and a wire 212 can be hung on the fixed pulley 201. One end of the wire 212 is fixed to the arm support portion 70, and a weight 211 is attached to the other end. The weight 211 has a weight that balances the weight of the arm support 70, the arm 60, and the X-ray source 40. As a result, a force equal to the gravity applied to the weight 211 can be applied upward to the arm support portion 70 by the wire 212 to support the arm support portion 70.

Although not shown, the X-ray source 40 that generates X-rays has a built-in rotary anode and cathode, and thermoelectrons generated from the cathode collide with the rotary anode to generate X-rays.

The X-ray movable diaphragm 50 is provided immediately below the X-ray source 40. Although not shown, the X-ray movable diaphragm 50 has two pairs of movable restricting blades, and each pair of operation restricting blades opens and closes in two directions orthogonal to each other in the same plane, thereby reducing the X-ray irradiation field. adjust. The brake release button 85 and the ultrasonic distance measuring unit 90 are provided in the X-ray movable diaphragm 50.

The arm 60 includes a substantially cylindrical first arm 61, a substantially cylindrical second arm 62 having an outer diameter smaller than the inner diameter of the first arm 61, and a rod-shaped outer diameter smaller than the inner diameter of the second arm 62. And the third arm 63, the third arm 63 is accommodated in the second arm 62, and the second arm 62 and the third arm 63 are configured to be accommodated in the first arm 61. Then, by pulling out the third arm 63 from the second arm 62 and pulling out the second arm 62 from the first arm 61, the arm 60 expands and contracts. The X-ray source 40 is disposed at the tip (open end) of the third arm 63.

In this embodiment, the X-ray movable diaphragm 50 is provided with a positioning handle (not shown). The operator grasps the positioning handle and moves the arm 60 up and down and horizontally moves the arm 60, so that the arm support unit 70, the arm 60, the X-ray source 40, and the X-ray movable diaphragm 50 are integrated. Configured to move. In addition, by providing the positioning handle with the brake release button 85, the brake release button 85 may be pushed down when the operator grips the positioning handle. As a result, the brake unit 80 can be released simply by the operator holding the positioning handle.

Next, the rail, brake part, and arm support part of the mobile X-ray apparatus will be further described with reference to FIG. As shown in FIG. 2 (a), the arm support portion 70 includes a housing portion 70a, a gear portion 71 that meshes with the rail 32, a rotation shaft portion 72 of the gear portion 71, and a rotation shaft with respect to the housing portion 70a. And a rotation support part 73 that rotatably supports the part 72. 2 (a) to 2 (c), for convenience of explanation, a state in which the housing part 70a is removed (the housing part 70a is shown by a one-dot chain line) is shown. A brake unit 80 is provided at a position different from the gear unit 71, the rotation shaft unit 72, and the rotation support unit 73 along the axial direction of the support column 30. As shown in FIG. 2 (b), the gear portion 71 engages with the rail 32 and restricts the ascending / descending direction of the arm support portion. The brake unit 80 operates according to the control of the control unit 12, and brakes and stops the up-and-down movement of the arm support unit 70.

The brake unit 80 may be of any type as long as it brakes the rotation of the gear unit 71, and may be configured using, for example, an electromagnetic brake. In this embodiment, an example using a brake unit 80 using a brake pad will be described.

As shown in FIGS. 2 (a) and 2 (b), the brake unit 80 is in contact with the inner wall surface of the groove 31 in the support column 30 and connects the two brake pads 81 to apply the brake, and the two brake pads. A substantially rod-shaped pad coupling portion 82 that expands and contracts the distance between 81 and 81 and positions the brake pad 81 in contact with or not in contact with the inner wall surface of the groove portion 31, and a brake drive device that performs expansion and contraction of the pad coupling portion 82 83, and a brake control circuit 84 that receives a control signal from the control unit 12 and performs drive control on the brake drive device 83. The brake driving device 83 and the brake control circuit 84 are fixed and accommodated in the housing part 70a. The pad connecting portion 82 is supported so as to be extendable and contractable with respect to the brake driving device 83. Each brake pad 81 is provided at both ends of the pad connecting portion 82.

At the time of braking, as shown in FIG. 2 (c), the pad connecting portion 82 extends, and the two brake pads 81 come into contact with the inner wall surface 31a of the groove portion 31 to apply the braking.

Next, based on FIG. 4, the internal configuration relating to the positioning process of the mobile X-ray apparatus 1 will be described. As shown in FIG. 4, the control unit 12 is electrically connected to the operation panel 11, the ultrasonic distance measuring unit 90, and the brake control circuit 84 of the brake unit 80. The brake control circuit 84 is electrically connected to the brake driving device 83 and the brake release button 85.

Before starting X-ray imaging, the operator inputs a distance between the source image receiving surfaces (hereinafter referred to as “SID target value”) suitable for X-ray imaging (inspection) to be executed through the operation panel 11. The ultrasonic distance measuring unit 90 measures the distance to the X-ray source 40 and the distance measurement object located immediately below the X-ray source 40, and calculates a measurement value. The control unit 12 compares the SID target value and the calculated value, and outputs a braking instruction signal to the brake control circuit 84 when a predetermined stop condition is satisfied. The brake control circuit 84 drives the brake driving device 83 according to the braking instruction signal and applies the brake (extends the pad connecting portion 82). When the brake release button 85 is pressed, a release instruction signal is output from the brake release button 85 to the brake control circuit 84. The brake control circuit 84 drives the brake driving device 83 in accordance with the release instruction signal, and releases the brake (shrinks the pad connecting portion 82).

Next, the processing flow of the first embodiment will be described with reference to FIGS. In the following, description will be given in the order of each step in FIG.

(Step S1)
An operator inputs an SID target value suitable for X-ray imaging (inspection) to be executed from the operation panel 11, and the control unit 12 acquires the information (S1).

(Step S2)
Start positioning. The operator holds the positioning handle (not shown) and moves the arm 60 up and down. When the ascending / descending operation is started, the distance from the ultrasonic distance measuring unit 90 to the distance measuring object is measured in real time by the ultrasonic distance measuring unit 90, and the measured value is detected as needed (S2). The measured value is output to the control unit 12.

(Step S3)
The control unit 12 determines whether or not the measurement value satisfies a predetermined stop condition (S3). Strictly speaking, since the SID is the distance from the focal point in the X-ray source 40 to the X-ray incident surface of the X-ray detector 4, the measured value indicating the distance from the ultrasonic distance measuring unit 90 to the distance measurement object. When the SID and the SID are directly compared, an error resulting from the difference in the positions of the ultrasonic distance measuring unit 90 and the X-ray source 40 occurs. However, since the distance from the X-ray source 40 to the ultrasonic distance measuring unit 90 is constant and the distance is known, the distance from the X-ray source 40 to the distance measurement object is assumed to be a measured value and processed. To proceed. That is, for the SID target value, the value obtained by correcting the distance from the X-ray source 40 to the distance measurement object may be compared with the measured value, or the measured value may be corrected as described above, and then the SID. The target value may be compared.

Furthermore, the value used for the determination process in this step may be calculated by adding or subtracting the subject thickness or the X-ray detector thickness to the measured value. Hereinafter, this value is referred to as a “calculated value”. However, since the calculated value is a value obtained based on the measured value, the calculated value may be read as the measured value in the following description.

The “calculated value” is calculated differently depending on whether or not the subject 2 is thick. For example, as shown in FIG. 6 (a), when there is a couch top just below the ultrasonic measurement unit 90, if the measured value is h and the thickness of the X-ray detector 4 is a, the control The unit 12 obtains a value (ha) obtained by subtracting the thickness a of the X-ray detector 4 from the measured value h as a calculated value.

Also, as shown in FIG. 6 (b), when the subject 2 is located directly below the ultrasonic distance measuring unit 90, the subject at the time of inputting imaging conditions at the start of the examination (step S1 above) The thickness b is also input at the same time. Then, the control unit 12 obtains a value (h + b) obtained by adding the subject thickness b to the measured value h as a calculated value. The body thickness information can be input from the operation panel 11 by the operator, or the body thickness data of the subject 2 can be stored in advance in a storage device in the main body 10 (not shown) and the data can be used. Furthermore, the control unit 12 may estimate the body thickness based on personal information such as the height and weight of the subject.

For example, the physique statistical data is stored in advance in a storage device (not shown) of the main body unit 10, and the control unit 12 stores the physique statistical data, the height and weight of the subject 2, and the part information set as the imaging conditions. Based on this, the body thickness limited to the imaging region of the subject may be estimated. As described above, since the calculation value can be obtained in a mode in which the object thickness is considered and a mode in which the object thickness is not considered, the operation panel 11 is provided with a selection unit for selecting each mode in advance. It may be left. Then, the control unit 12 may be configured to obtain the calculated value using the mode selected by the operator via the selection unit.

The use of the mode considering the subject thickness and the mode not considering the subject thickness may be performed according to the positioning procedure. For example, as a positioning procedure, first, the X-ray detection unit 4 is installed on the bed 3 so that the X-ray source 40 satisfies the SID target value. Then, the subject 2 is moved onto the X-ray detector 4.

体 When positioning with this procedure, it is not necessary to add body thickness to the measured value. Therefore, the operation panel 11 selects a mode that does not consider the subject thickness. As another example of the positioning procedure, first, the X-ray detection unit 4 is installed on the bed 3 and the subject 2 is moved thereon. Then, the X-ray source 40 is arranged at a position so as to satisfy the SID target value. When positioning is performed according to this procedure, it is necessary to add the body thickness to the measurement value, so a mode that considers the subject thickness is selected.

The stop condition may be based on whether the calculated value matches the SID target value, or taking into account the measurement error of the measurement value, and setting an allowable range in which the measurement error is added to or subtracted from the SID target value. A condition may be whether the calculated value falls within the allowable range.

If the result of this step is “Yes”, the process proceeds to step S4. If “No”, the process returns to step S2, and the lifting operation of the arm 60 is continued.

(Step S4)
The control unit 12 outputs a braking instruction signal to the brake control circuit 84, and the brake driving device 83 extends the pad connecting unit 82. Then, each pad 81 comes into contact with the inner wall surface in the groove 31 of the support column 30, and braking is applied by friction (S4). Thereby, the raising / lowering operation of the arm support part 70, the arm 60, the X-ray source 40, and the X-ray movable diaphragm 50 is stopped. At this time, a notification unit (not shown) may be provided so as to notify the operator that the brake is applied due to the generation of a beep sound or the like.

(Step S5)
The operator extends and contracts the arm 60 to perform horizontal positioning, and arranges the X-ray source 40 so as to face the X-ray detector 4 with the subject 2 interposed therebetween (S5).

In the above description, after determining the height of the X-ray source 40, the X-ray source 40 is disposed opposite to the subject 2, but the order of positioning may be reversed. Therefore, step S2 to step S4 may be performed after performing step S5.

According to the present embodiment, easy positioning can be realized by measuring the height of the X-ray source in real time during positioning and stopping the raising / lowering of the X-ray source when the stop condition is satisfied. In particular, even an inexperienced operator can perform accurate positioning in a short time.

In this embodiment, the chopped rail 32 is disposed on the support column 30, the gear portion 71 is disposed on the arm support portion 70, the rail 32 and the gear portion 71 are meshed, and the arm support portion 70 is attached to the rail 32. Although it is configured to move up and down along, the present invention is not limited to this configuration. In the present invention, as shown in FIGS. 3 (a) and 3 (b), the support 30 is provided with a mechanism that inverts the arm support 70 upward, and the weight of the arm support 70 is supported by the

wires

205 and 212. For this reason, the rail 32 may be a simple groove, and the arm support portion 70 may be provided with a convex portion that is shaped to engage with the groove. In addition, as the brake unit 80, an electromagnetic brake is used, and a structure in which the brake is applied to the metal support 30 by electromagnetic force to apply braking can be used.

<Second embodiment>
The second embodiment is an embodiment that notifies the operator of the moving direction for approaching the SID target value. Hereinafter, the second embodiment will be described with reference to FIGS. FIG. 7 is an explanatory diagram showing the overall configuration of the mobile X-ray apparatus according to the second embodiment. FIG. 8 is an explanatory diagram showing an internal configuration related to the positioning process of the mobile X-ray apparatus 1a according to the second embodiment. FIG. 9 is a flowchart showing an aspect of a processing flow of the mobile X-ray apparatus 1a according to the second embodiment. FIG. 10 is a flowchart showing another aspect of the processing flow of the mobile X-ray apparatus 1a according to the second embodiment.

The mobile X-ray apparatus 1a according to the second embodiment, in addition to the mobile X-ray apparatus 1 according to the first embodiment (see FIG. 1), in order to bring the measured value (X-ray source position) closer to the SID target value A notification unit for notifying the operator of the moving direction of. The mobile X-ray apparatus 1a shown in FIG. 7 includes a display 100 that displays an arrow indicating a moving direction for bringing the X-ray source close to the SID target value as a notification unit. Then, as shown in FIG. 8, the control unit 12 and the display device 100 are electrically connected.

Next, the processing flow of the mobile X-ray apparatus 1a according to the second embodiment will be described in the order of steps in FIG. Note that redundant description of steps already described in FIG. 5 is omitted.

(Step S11)
If it is determined in step S3 that the stop condition is not satisfied, the control unit 12 compares the magnitude relationship between the calculated value in step S3 and the SID target value. If the calculated value is smaller than the SID target value (corresponding to affirmative), the process proceeds to step S12. If the calculated value is larger than the SID target value (corresponding to negative), the process proceeds to step S13.

(Step S12)
The control unit 12 outputs a control signal for displaying an upward arrow (direction in which the arm 60 is raised) to the display device 100, and the display device 100 displays an upward arrow (S12). The operator visually recognizes it and raises the arm 60. Thereafter, the process returns to step S2.

(Step S13)
The control unit 12 outputs a control signal for displaying an arrow pointing downward (a direction in which the arm 60 is lowered) to the display device 100, and the display device 100 displays a downward arrow (S13). The operator visually recognizes it and lowers the arm 60. Thereafter, the process returns to step S2.

Also, as another mode of notification of the moving direction, a voice generating unit may be provided instead of the display, and a sound may be notified when moving in a direction away from the SID target value. As described above, since the ultrasonic distance measuring unit 90 can measure the distance between the X-ray source 40 and the distance measuring object in real time, the control unit 12 determines the current moving direction, The operator may be informed whether the moving direction is correct. Specific processing will be described in the order of steps in FIG. Since step S11 is the same as that described with reference to FIG.

(Step S21)
In the determination of the magnitude relationship in step S11, if it is determined that the SID target value is smaller than the calculated value, the change tendency of the calculated value is determined. Specifically, the magnitude relationship between the previously calculated value (t−1) and the currently calculated value (t) is compared. If the calculated value (t) calculated this time is larger than the previously calculated value (t−1), it means that the movement is in the direction approaching the SID target value. Therefore, the process returns to step S2, and the movement of the arm 60 is continued. If the calculated value (t) calculated this time is smaller than the previously calculated value (t-1), it means that the movement is away from the SID target value, and the process proceeds to step S23.

(Step S22)
If it is determined in step S11 that the SID target value is greater than the calculated value, the change tendency of the calculated value is determined. Specifically, the magnitude relationship between the previously calculated value (t−1) and the currently calculated value (t) is compared. If the calculated value (t) calculated this time is smaller than the previously calculated value (t-1), it means that the movement is in the direction approaching the SID target value. Therefore, the process returns to step S2, and the movement of the arm 60 is continued. If the calculated value (t) calculated this time is larger than the calculated value (t-1) calculated last time, it means that the movement is away from the SID target value, so the process proceeds to step S23.

(Step S23)
The control unit 12 outputs a control signal instructing the sound generation unit to generate a warning sound, and generates a warning sound from the sound generation unit (S23). Thereafter, the process returns to step S2.

According to this embodiment, when the arm 60 is moved up and down in the direction away from the SID target value, an error in operation can be transmitted to the operator by generating a warning sound. As a result, positioning becomes easier.

<Third embodiment>
The third embodiment is an embodiment in which when the calculated value approaches the SID target value, a brake having a relatively weak braking force is operated to reduce the ascending / descending speed. Hereinafter, the third embodiment will be described based on FIG. 11 and FIG.

In the third embodiment, the brake unit 80 applies a relatively weak braking force, and without causing the arm 60 to stop, causes the first brake unit to decelerate the lifting speed and a relatively strong braking force to act, A first brake part for stopping the arm 60. In this specification, the 1st brake part and the 2nd brake part should just be different in braking force, and the same brake device as the case where the 1st brake part and the 2nd brake part are constituted using a plurality of different brake devices. Including the case where the braking force of the vehicle is changed.

As an example of the former, for example, the first brake part and the second brake part may be constituted by electromagnetic brakes having different braking forces. As an example of the latter, one electromagnetic brake for stopping may be provided to control the strength of braking force. For example, ON and OFF are alternately repeated by PMW (Pulse Width Modulation) control. At this time, the ON timing may be controlled to be longer as the SID target value is approached. Further, in the brake part including the brake pad and the pad connecting part used in the first embodiment, the pad connecting part is extended as the SID target value is approached, and the frictional force between the pad and the inner wall surface of the groove part 31 is gradually increased. Can also be realized.

In the present embodiment, as shown in FIG. 11, the brake control circuit 84 and the first brake drive device 86 that drives the brake mechanism for applying a relatively weak braking force to the brake unit 80 are relatively strong. The operation will be described by taking as an example a mobile X-ray device provided with a second brake driving device 87 for driving a brake mechanism for applying a braking force. Next, the flow of processing of the mobile X-ray apparatus according to the third embodiment will be described along the order of steps in FIG.

(Step S41)
The control unit 12 outputs a braking instruction signal to the brake control circuit 84, and the second brake driving device 87 is activated to apply relatively strong braking to the lifting operation of the arm 60, and the lifting operation is stopped. (S41).

(Step S42)
The control unit determines whether or not the calculated value satisfies a deceleration condition (S42). In this embodiment, the deceleration conditions are determined as follows, but this is only an example, and the method for determining the deceleration conditions is not limited to the following. In order to determine the deceleration condition, a distance from the SID target value to the position where the arm 60 starts to be decelerated (hereinafter referred to as “deceleration start distance”) is determined in advance. Then, the range included in the position of the deceleration start distance in the vertical direction with the SID target value as the center is set as the deceleration range. More specifically, if the deceleration start distance is represented by α, the control unit 12 determines whether or not the absolute value of the difference between the SID target value and the calculated value satisfies the following expression (1) (S42).

｜ SID target value-calculated value ｜ ≦ α ・・・ (1)
If the expression (1) is satisfied, the process proceeds to step S43. If not satisfied, the process returns to step S2.

(Step S43)
The control unit 12 outputs a braking instruction signal to the brake control circuit 84. Then, the first brake driving device 86 is activated, and relatively weak braking is applied to the lifting / lowering operation of the arm 60, and the lifting / lowering speed is reduced (S43). Thereafter, the process returns to step S2.

In this embodiment, the operator approaches the SID target value by applying a weak brake when approaching the SID target value. As a result, it is possible to prompt the operator to operate slowly. By doing so, even when the time resolution of the ultrasonic distance measuring unit is poor, it can be expected that the brake is accurately applied and the accuracy of positioning is increased.

<Fourth embodiment>
The fourth embodiment is an embodiment in which horizontal positioning is performed using the measurement value of the ultrasonic distance measuring unit. Here, “horizontal positioning” corresponds to the processing in step S5 described above with reference to FIG. In addition, the horizontal direction here means the direction defined in the plane orthogonal to the axial direction of a support | pillar. The fourth embodiment will be described below with reference to FIGS. FIG. 13 is an explanatory diagram showing the internal configuration of the mobile X-ray apparatus according to the fourth embodiment. FIG. 14 is a flowchart showing a processing flow of the mobile X-ray apparatus according to the fourth embodiment. FIG. 15 is an explanatory diagram illustrating a process of searching for a horizontal positioning position.

First, the configuration of the mobile X-ray apparatus according to the fourth embodiment will be shown based on FIG. As shown in FIG. 13, the mobile X-ray apparatus according to the fourth embodiment applies a brake to the horizontal movement of the arm 60 (the expansion and contraction operation of the arm 60) and a horizontal brake unit 110 and a horizontal brake that prohibit the horizontal movement. A brake release button 120 for instructing the part 110 to release the brake is provided.

The horizontal brake unit 110 only needs to lock the expansion and contraction operation of the arm 60 and hold the horizontal length of the arm 60 at the locked position. Any type.

In the present embodiment, the horizontal brake 110 includes a horizontal brake control circuit 111 and a horizontal brake driving device 112. Instead of the horizontal brake unit 110, a notification unit for notifying that the X-ray source 40 is arranged at an optimal position may be provided. The control unit 12 is electrically connected to the horizontal brake control circuit 111. When the control unit 12 determines that the X-ray source 40 is disposed at the optimum position by the process described later, the horizontal brake control circuit 111 In response to this, a braking instruction signal for operating the brake is output. The horizontal brake control circuit 111 receives the braking instruction signal and operates the horizontal brake driving device 112 to lock the horizontal movement of the arm 60. The horizontal brake release button 120 is also electrically connected to the horizontal brake control circuit 111. When the horizontal brake release button 120 is operated, a release signal is output to the horizontal brake control circuit 111. In response to the release signal, the horizontal brake control circuit 111 controls the horizontal brake driving device 112 to release the brake. The horizontal brake release button 120 may be integrated with the brake release button 85 described in the first embodiment.

That is, the brake release button 85 may be configured to release both the lifting and lowering brakes. Thereby, two brakes can be cancelled | released by one operation, and the improvement of operativity can be anticipated.

Next, the processing flow of the mobile X-ray apparatus according to this embodiment will be described along the steps of FIG.

(Step S51)
While extending or contracting the arm 60, the X-ray source 40 is moved in the horizontal direction. While moving, the ultrasonic distance measuring unit 90 measures the distance to the distance measuring object. In this step, the arm 60 is horizontally moved so that the X-ray source 40 completely passes through the body width of the subject 2 (S51).

(Step S52)
The control unit 12 detects the minimum value of the ultrasonic distance measuring unit 90 (S52). The horizontal position indicating the minimum value is a position where the distance between the distance measuring body and the ultrasonic distance measuring unit 90 is the smallest, and indicates a horizontal position where the body thickness of the subject 2 is the thickest.

(Step S53)
The operator horizontally moves the arm 60 so that the X-ray source 40 moves in a direction opposite to the center position of the body width of the subject 2 (S53). At the same time, the ultrasonic distance measuring unit 90 performs distance measurement.

(Step S54)
The control unit 12 determines whether or not the calculated value using the ultrasonic distance measuring unit 90 matches the minimum value detected in step S52 (S54). If “Yes”, the process proceeds to Step S55, and if “No”, the process returns to Step S53.

(Step S55)
The control unit 12 outputs a braking instruction signal to the horizontal brake control circuit 111, the horizontal brake driving device 112 is activated, and the horizontal movement of the arm 60 is stopped (S55). This completes the horizontal positioning.

The above processing is effective when the subject 2 has a convex shape, but this is not always the case. Therefore, a description will be given of processing in the case of a flat shape (for example, a case where the subject 2 is not mounted on the X-ray detector 4 and the distance to the X-ray detector 4 is measured) is described.

First, the mobile X-ray apparatus is provided with an arm expansion / contraction amount detection unit, such as a potentiometer, which acquires the expansion / contraction amount along the horizontal direction of the arm 60 in real time.

Then, the distance is measured using the ultrasonic distance measuring unit 90 while the arm 60 is contracted most, and then the arm 60 is extended (i.e., the X-ray source 40 is moved horizontally). The extension amount of 60 is measured, and the distance measurement value and the extension amount are stored in association with each other. Then, as before, the X-ray source 41 is moved and moved horizontally so as to cross the X-ray detector 4.

As shown in FIG. 15, the measured value becomes the minimum value when the X-ray detector 4 and the ultrasonic measuring instrument 90 are in a position facing each other. Therefore, the control unit 12 determines the horizontal position (X) where the measurement value by the ultrasonic distance measurement unit 90 is the first minimum value and the horizontal position (X + L) when the measurement value is the last minimum value. , L indicates the width of the X-ray detector 4). Then, the control unit 12 calculates the horizontal position (X + L / 2) when the measured value becomes the minimum value.

After that, the operator performs an operation of contracting the arm 60. At this time, the control unit 12 detects the contraction amount of the arm 60 in real time based on the output value from the arm expansion / contraction amount detection unit, and at the position (X + L / 2) where the contraction amount becomes (L / 2). Apply the horizontal brake. This completes the horizontal positioning.

According to this embodiment, horizontal positioning can also be easily performed.

In each of the above embodiments, the operator performs the lifting / lowering operation and the horizontal movement of the arm 60 during positioning. However, a drive device that performs the lifting / lowering movement and the horizontal movement, for example, a motor may be provided. Then, the control unit 12 may control the rotation of the motor and stop the rotation of the motor when the SID target value is reached. Thereby, it can implement | achieve this invention by drive control of a motor instead of a brake part.

Further, the mobile X-ray apparatus may be configured by arbitrarily combining the above embodiments.

1, 1a Mobile X-ray device, 10 body part, 20 moving part, 30 struts, 40 X-ray source, 50 X-ray movable diaphragm, 60 arm, 70 arm support part, 80 brake part, 90 ultrasonic distance measuring part

Claims

The main body,
A moving part for causing the main body part to travel on a floor surface;
A support column erected on the moving part;
An X-ray source that generates X-rays;
An arm for supporting the X-ray source;
An arm support that supports the arm so as to be movable up and down along the axial direction of the support;
A brake portion for braking the lifting and lowering movement of the arm support portion;
A distance measuring unit for measuring a distance from the X-ray source to a distance measuring object located under the X-ray source;
A first receiving unit for receiving a distance between focal image receiving surfaces indicating a distance from the X-ray source to an X-ray image receiving surface included in an X-ray detector that detects the X-rays and outputs an X-ray signal indicating the intensity. One input section,
Control for comparing the measurement value obtained by the measurement and the distance between the focus image receiving surfaces, and performing control for braking the lifting and lowering operation on the brake unit based on the comparison result And
A mobile X-ray apparatus characterized by comprising:
Based on the comparison result by the control unit, a notification unit for notifying the direction in which the arm should be moved along the axial direction of the support column is further provided in order to bring the measurement value closer to the distance between the focus image receiving surfaces.
2. The mobile X-ray apparatus according to claim 1, wherein
The brake portion has a relatively weak braking force, a first brake portion for lowering the speed of the up-and-down movement, and a relatively strong braking force, and the arm support portion has a predetermined direction along the axial direction. Including a second brake part for stopping in position,
The control unit activates the first brake unit when the difference between the distance between the focus image receiving surfaces and the measurement value is within a predetermined deceleration range, and the measurement value is the difference between the distances between the focus image receiving surfaces. When the second brake part is activated,
2. The mobile X-ray apparatus according to claim 1, wherein
A second input unit for receiving input of body thickness information indicating the body thickness of the subject;
The control unit compares the measured value and the calculated value calculated based on the body thickness of the subject, and the distance between the focus image receiving surfaces,
2. The mobile X-ray apparatus according to claim 1, wherein
A horizontal brake portion for braking the horizontal movement of the arm configured to move horizontally in a plane perpendicular to the axial direction of the support;
The distance measuring unit performs the measurement at each position in the plane that changes due to the horizontal movement,
The control unit detects a minimum value of the measurement values obtained at each position, and operates the horizontal brake unit at a position in the plane corresponding to the minimum value;
2. The mobile X-ray apparatus according to claim 1, wherein
A positioning control method for a mobile X-ray apparatus including an X-ray source supported so as to be movable up and down,
Measuring a distance from the X-ray source to a distance measuring object located under the X-ray source;
A predetermined distance between the focal planes and the distance to the X-ray detector that detects the X-ray source and the X-ray generated from the X-ray source and outputs an X-ray signal indicating the intensity. Comparing the distance between the focus image receiving surfaces indicating the measured value obtained by the measurement, and applying the braking to the ascent and descent based on the comparison result;
A positioning control method for an X-ray imaging apparatus, comprising: