CN111407303A - Scanning beam limiting and collimating mechanism of X-ray source and control method thereof - Google Patents

Abstract

The invention relates to the field of X-ray shooting equipment, in particular to a scanning type beam limiting collimation mechanism of an X-ray source and a scanning control method thereof. The invention adopts the following technical scheme: the scanning device comprises a scanning collimation block, a scanning direction limiting block and a scanning driving device; the scanning collimation block is driven by the scanning driving device to move along the direction of the first scanning limiting block towards the second scanning limiting block along the upper surface of the scanning direction limiting block. The invention has the advantages that: the scanning collimation block with a unit light field channel in the middle is driven to move along the upper surface of the scanning direction limiting block with an effective light field opening in the middle for scanning, and the scattered X-rays are shielded and absorbed by the scanning collimation block, the scanning direction limiting block and the transverse limiting block by matching with the transverse limiting block, so that the instantaneous radiation dose and the total radiation dose of the environment are reduced, medical staff and a photographed person are protected, and the image quality is improved.

Description

Scanning beam limiting and collimating mechanism of X-ray source and control method thereof

technical field

The invention relates to the field of X-ray photographing equipment, in particular to a scanning beam limiting and collimating mechanism of an X-ray source and a control method thereof.

Background technique

During medical X-ray inspection, the conventional collimator adjusts the size of the X-ray light field by adjusting the size of the window. The radiation dose and radiation dose rate in the environment are not only related to the X-ray exposure parameters, the shielding performance of the collimator and Light field size is related. In particular, when the X-rays are emitted from the collimator, there are a large number of scattered rays in the X-ray beam, and these rays are directly scattered into the environment, which will cause radiation pollution and affect the image quality.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a scanning beam limiting and collimating mechanism and a control method of an X-ray source that can reduce the instantaneous radiation dose and total radiation dose in the environment, thereby protecting medical staff and subjects, and improving image quality.

In order to achieve the above purpose, the present invention adopts the following technical scheme: a scanning beam limiting and collimating mechanism of an X-ray source, including a scanning and collimating block, a scanning direction limiting block and a scanning driving device, and a scanning and collimating block. It includes a first collimation block and a second collimation block, and the scan direction limit block includes a first scan direction limit block and a second scan direction limit block, and the first collimation block and the second collimation block are spaced apart to form Unit light field channel, the first scanning direction limit block and the second scanning direction limit block are spaced apart to form an effective light field opening; the scanning collimation block is driven by the scanning driving device along the first scanning limit block toward the second scanning The direction of the limit block is moved against the scan to the upper surface of the limit block.

Further, a lateral limit block is arranged between the first collimation block and the second collimation block, and the lateral limit block includes a first lateral limit block and a second lateral limit block, the first lateral limit block and the second lateral limit The blocks are respectively movably arranged at the front and rear ends of the first collimating block and the second collimating block.

Further, a start point proximity switch is provided on the first scanning direction limit block, an end point proximity switch is provided on the second scan direction limit block, and an edge close to the start point is provided at the bottom of the first alignment block near the edge of the second alignment block. The switch corresponds to the matched first trigger piece, and the bottom of the second collimation block is provided with a second trigger piece corresponding to the end point proximity switch close to the edge of the first collimation block.

Further, a first buffer zone is formed between the start point proximity switch and the edge of the first scan direction limit block close to the second scan direction limit block, and the end point proximity switch and the second scan direction limit block are close to the first scan direction limit block. A second buffer area is formed between the edges of the blocks, and the widths of the first buffer area and the second buffer area are both larger than the width between the first collimation block and the bottom of the second collimation block.

Further, the cross-sections of the first collimation block, the second collimation block, the first scanning direction limiting block and the second scanning direction limiting block are all fan-shaped rings with the focus of the X-ray tube as the center of the circle, and the scanning drive The device drives the first collimating block and the second collimating block to move in an arc with the focus of the X-ray tube as the center of the upper surface of the first scanning direction limiting block and the second scanning direction limiting block.

Preferably, a gap is provided between the bottom of the scanning alignment block and the upper surface of the scanning direction limiting block; and a gap is provided between the lateral limiting block and the scanning alignment block.

A scanning control method for a scanning beam limiting and collimating mechanism of an X-ray source, comprising the following steps:

S01. Set the running speed of the scanning collimation block according to the exposure parameters of the X-ray source.

S02. Trigger the instruction to start scanning, so that the scanning alignment block runs at the set running speed.

S03. Control the X-ray ball before the unit light field channel between the first scanning collimation block and the second scanning collimation block enters the effective light field opening between the first scanning direction limiting block and the second scanning direction limiting block The tube starts exposure, and the X-ray tube ends exposure when the unit light field channel leaves the effective light field opening.

S04. After the unit light field channel leaves the effective light field opening, the scanning collimation block stops scanning and resets.

Specifically, in step S01, the operation speed of the scanning and collimating block is calculated according to the formula: scanning speed=unit light field width/irradiation time, and the irradiation time is calculated according to the formula: irradiation time=target current time product/X-ray source tube current Calculation.

Further, in step S03, before the unit light field channel enters the effective light field opening, the first trigger piece at the bottom of the first collimation block triggers the starting point proximity switch on the first scanning direction limit block and controls the X-ray tube to start exposure. ; After the unit light field channel leaves the effective light field opening, the second trigger piece at the bottom of the second collimation block triggers the end point proximity switch on the second scanning direction limit block and controls the X-ray tube to end exposure.

Further, when the scanning alignment block is reset, the first trigger piece on the first alignment block triggers the start point proximity switch on the first scanning direction limit block and stops after a delay.

The advantage of the present invention is that the scanning collimation block with the unit light field channel in the middle is driven to move and scan the upper surface of the limiting block along the scanning with the effective light field opening in the middle, and at the same time, the lateral limiting block is matched, so that the X-ray can only be transmitted from The unit light field channel in the middle of the scanning collimation block is emitted and scanned along the effective light field opening, so that the remaining scattered X-rays are shielded and absorbed by the scanning collimation block, the scanning direction limit block and the lateral limit block, thereby reducing the environment. Instantaneous radiation dose and total radiation dose, protect medical staff and subjects, and improve image quality.

Description of drawings

Accompanying drawing 1 is the overall structure diagram of the beam limiting and collimating mechanism in the embodiment;

2 is a cross-sectional view of the beam-limiting and collimating mechanism in the embodiment;

Accompanying drawing 3 is the exposure development view of the beam-limiting and collimating mechanism photographing process in the embodiment;

FIG. 4 is a flow chart of the control method of the beam limiting and collimating mechanism in the embodiment.

Detailed ways

Embodiment 1: Referring to Figures 1-3, a scanning beam limiting and collimating mechanism of an X-ray source includes a scanning and collimating block 1, a scanning direction limiting block 2 and a scanning driving device 3, and the scanning and collimating Block 1 includes a first collimation block 11 and a second collimation block 12, scan direction limit block 2 includes a first scan direction limit block 21 and a second scan direction limit block 22, and the first collimation block 11 and the first scan direction limit block 22. The two collimating blocks 12 are spaced apart to form a unit light field channel 13, and the first scanning direction limiting block 21 and the second scanning direction limiting block 22 are spaced apart to form an effective light field opening 23; the scanning alignment block 1 is driven by scanning The device 3 is driven to move against the upper surface of the restriction block 2 along the direction of the first scanning restriction block 21 toward the second scanning restriction block 22 .

In this embodiment, the scanning and collimating block 1 is used to limit and collimate the X-rays emitted from the X-ray tube, so that the X-rays emitted from the X-ray tube can only pass through the first collimation block 11 The unit light field channel 13 between the second collimation block 12 and the second collimation block 12 passes through, and the other will be shielded and absorbed by the first collimation block 11 and the second collimation block 12. When scanning the collimating block 1 for moving scanning, The X-ray emitted by the X-ray tube will move with the movement of the unit light field channel 13 of the scanning and collimating block. The mobile scanning can be performed along the effective light field opening 23 between the first scanning direction limiting block 21 and the second scanning direction limiting block 22, so that the X-ray emitted by the X-ray tube can be per unit width of the light field channel 13. Scanning and detection is performed along the effective light field opening 23 to meet the area to be photographed; since the actual width of the X-ray emission is only the width of the unit light field channel 13, the smaller the width, the easier it is to control, which can reduce the exposure of X-rays in the environment. The instantaneous radiation dose; the scanning collimation block 1 and the scanning direction limiting block 2 can effectively suppress the X-ray scattered into the environment when the X-ray tube is exposed, reduce the total radiation dose in the environment, and protect medical staff and victims. photographers, improve image quality. Among them, the first scanning direction limiting block 21 and the second scanning direction limiting block 22 can be moved left and right along the scanning direction of the scanning collimation block 1, so that the width of the effective light field opening 23 can be adjusted as required, that is, the X range of radiographic scans.

Wherein, a lateral limit block 4 is further provided between the first collimation block 11 and the second collimation block 12 , and the lateral limit block 4 includes a first lateral limit block 41 and a second lateral limit block 42 , and the first lateral limit block 41 and the second lateral limiting block 42 are respectively movably disposed at the front and rear ends of the first collimating block 11 and the second collimating block 12 . The lateral limiting block 4 restricts the front and rear ends of the unit light field channel between the first collimating block 11 and the second collimating block 12, thereby further limiting the length of the unit light field channel 13, wherein the first lateral limiting block 41 and the first The two lateral limiting blocks 42 can move back and forth along the unit light field channel 13 between the first collimating block 11 and the second collimating block 12 , so that the length of the unit light field channel 13 can be adjusted, thereby adjusting the overall area of X-ray scanning . Among them, the scanning collimation block 1 , the scanning direction limiting block 2 and the lateral limiting block 4 are all made of materials with good X-ray shielding and absorption properties, such as aluminum blocks or lead blocks.

Specifically, the cross sections of the first collimation block 11 , the second collimation block 12 , the first scanning direction limiting block 21 and the second scanning direction limiting block 22 are all centered on the focus P of the X-ray tube The scanning driving device 3 drives the first collimating block 11 and the second collimating block 12 to stick to the upper surface of the first scanning direction restricting block 21 and the second scanning direction restricting block 22 to form an X-ray tube. The focus P is the center of the circle to make an arc motion.

Further, a start point proximity switch 211 is provided on the first scanning direction limit block 21 , an end point proximity switch 221 is provided on the second scanning direction limit block 22 , and the bottom of the first alignment block 11 is close to the bottom of the second alignment block 12 . The edge is provided with a first trigger piece 111 corresponding to the start point proximity switch 211 , and the bottom of the second alignment block 12 close to the edge of the first alignment block 11 is provided with a second trigger piece 121 corresponding to the end point proximity switch 221 .

In a further embodiment, by setting the corresponding matching start point proximity switch 211 , the first trigger piece 111 , the end point proximity switch 221 and the second trigger piece 121 on the scanning direction limiting block 2 and the scanning alignment block 1 , the It is used to detect the relative position of the unit light field channel 13 of the scanning collimation block on the effective light field opening 23 of the scanning direction limit block 2, and can be used to control the X-ray tube and the scanning driving device 3; specifically, the starting point is close to The switch 211 is set on the first scanning direction limit block 21, the first trigger piece 111 is set on the bottom of the first collimation block 11 near the edge of the second collimation block 12, and the end point proximity switch 221 is set on the second scanning direction limit On the block 22, the second trigger piece 121 is arranged at the bottom of the second collimation block 12 near the edge of the first collimation block 11; when the scanning and collimating block 1 is driven by the scanning driving device 3 from the first scanning to the limiting block 21 moves to the second scanning direction limit block 22, that is, moves along the scanning direction, so that when the first trigger piece 111 at the bottom of the first collimation block 11 reaches the top of the starting point proximity switch 211, the starting point proximity switch 211 is triggered, and the X is controlled. The ray tube starts to be exposed, and then the scanning driving device 3 continues to drive the scanning and collimating block 1 to move along the scanning direction, so that the unit light field channel 13 passes through the effective light field opening 23 for scanning and detection. When the second trigger piece 121 reaches above the end point proximity switch 221, the end point contact switch 221 is triggered to control the X-ray tube to end exposure, and at the same time control the scanning driving device 3 to stop driving, and move in the opposite direction of the scanning direction, that is, the reset direction During the reset process, when the first trigger piece 111 of the first collimation block 11 reaches the top of the starting point proximity switch 211 and triggers the starting point proximity switch 211, the delay control scanning driving device 3 stops driving the scanning and collimating block 1 moves, and the delay time can be determined according to the speed at which the scanning driving device 3 drives the scanning and collimating block 1, generally a few tenths of a second. At the same time, in order to prevent confusion caused by the triggering of the first trigger piece 111 and the second trigger piece 121 and the start point proximity switch 211 and the end point proximity switch 221, the first trigger piece 111 and the start point proximity switch 211 and the second trigger piece 121 and The end-point proximity switches 221 are staggered from each other, that is, the first trigger piece 111 and the start-point proximity switch 211 and the second trigger piece 121 and the end-point proximity switch 221 are located in different vertical planes, so that the second trigger piece 121 will not falsely trigger the start point proximity switch 211, the first trigger piece 111 will not trigger the end point proximity switch 221 by mistake. Wherein, the starting point proximity switch 211 and the end point proximity switch 221 may use Hall proximity switches, and correspondingly, the first trigger piece 111 and the second trigger piece 121 correspond to magnetic materials.

Specifically, a first buffer zone 241 is formed between the start point proximity switch 211 and the edge of the first scan direction limit block 21 close to the second scan direction limit block 22 , and the end point proximity switch 221 is close to the second scan direction limit block 22 A second buffer area 242 is formed between the edges of the first scanning direction limiting block 21 , and the widths of the first buffer area 241 and the second buffer area 242 are both larger than those between the bottoms of the first alignment block 11 and the second alignment block 12 The width of the unit light field channel 13 . The first buffer area 241 and the second buffer area 242 are used to ensure that the unit light field channel 13 has sufficient pre-exposure time for the X-ray tube when entering and leaving the effective light field opening 23. Since the first buffer area 241 and the second buffer area 242 Therefore, before the unit light field channel 13 enters the effective light field opening 23, the first trigger plate 111 has already triggered the starting point proximity switch 211, so that the X-ray tube starts to be exposed, thereby ensuring that the unit light field channel 13 When entering the effective light field opening 23, the X-ray tube can emit stable and effective X-rays. After the unit light field channel 13 leaves the effective light field opening 23, the second trigger piece 121 will trigger the end point proximity switch 221, so that the X-ray tube The exposure is ended to ensure that the X-ray tube can still emit stable and effective X-rays when the unit light field channel 13 leaves the effective light field opening 23 , thereby ensuring uniform irradiation intensity in the effective light field opening 23 and improving detection effectiveness.

Referring to FIG. 4 , the present application also provides a scanning control method for a scanning beam limiting and collimating mechanism of an X-ray source, including the following steps:

S01. Set the running speed of the scanning collimation block according to the exposure parameters of the X-ray source.

S02. Trigger the instruction to start scanning, so that the scanning and collimating block 1 runs at the set running speed.

S03. Control X before the unit light field channel 13 between the first collimating block 11 and the second collimating block 12 enters the effective light field opening 23 between the first scanning direction limiting block 21 and the second scanning direction limiting block 22 The X-ray tube starts exposure, and the X-ray tube ends the exposure when the unit light field channel 13 leaves the effective light field opening 23 .

S04. After the unit light field channel 13 leaves the effective light field opening 23, the scanning and collimating block 1 stops scanning and resets.

Specifically, in step S01, the running speed of the scanning and collimating block is calculated according to the formula: scanning speed=unit light field width/irradiation time, wherein the irradiation time is calculated according to the formula: irradiation time=target current time product/X-ray source tube The current is calculated. The target current time product reflects the irradiation intensity of the target, which can be set according to actual needs. The X-ray tube current is a parameter of the X-ray source, which can be set according to specific requirements.

Specifically, in step S03, before the unit light field channel 13 enters the effective light field opening 23, the first trigger piece 111 at the bottom of the first collimation block 11 triggers the start point proximity switch 211 on the first scanning direction limit block 21 and controls the control accordingly. The X-ray tube starts exposure; after the unit light field channel 13 leaves the effective light field opening 23, the second trigger piece 121 at the bottom of the second collimation block 12 triggers the end point proximity switch 221 on the second scanning direction limit block 22 and controls accordingly The X-ray tube ends the exposure.

Specifically, when the scanning alignment block 1 is reset in step S04 , the first trigger piece 111 on the first alignment block 11 triggers the start point proximity switch 211 on the first scanning direction limit block 21 and stops after a delay.

Of course, the above are only preferred embodiments of the present invention, and are not intended to limit the scope of use of the present invention. Therefore, any equivalent changes made on the principles of the present invention should be included in the protection scope of the present invention.

Claims (9)

1. A scanning-type beam-limiting and collimating mechanism of an X-ray source, characterized in that: comprising a scanning and checking alignment block, a scanning and checking direction limiting block and a scanning and checking driving device, and the scanning and checking-alignment block comprises a first alignment block. A collimation block and a second collimation block, the scan direction limit block includes a first scan direction limit block and a second scan direction limit block, and the first collimation block and the second collimation block are spaced apart to form a unit light field channel, the first scanning direction limiting block and the second scanning direction limiting block are spaced apart to form an effective light field opening; the scanning collimation block is driven by the scanning driving device along the first scanning limiting block toward the second scanning The direction of the limit block is moved against the scan to the upper surface of the limit block. 2 . The scanning beam limiting and collimating mechanism of an X-ray source according to claim 1 , wherein a lateral limiting block is arranged between the first collimating block and the second collimating block, so the The lateral limiting block includes a first lateral limiting block and a second lateral limiting block, and the first lateral limiting block and the second lateral limiting block are respectively movably arranged at the front and rear ends of the first and second alignment blocks. 3 . The scanning beam limiting and collimating mechanism of an X-ray source according to claim 2 , wherein the first scanning direction limiting block is provided with a starting point proximity switch, and the second scanning direction limiting block is provided with a starting point proximity switch. 4 . The end point proximity switch is arranged on the block, the bottom of the first alignment block is close to the edge of the second alignment block and a first trigger piece corresponding to the start point proximity switch is provided, and the bottom of the second alignment block is close to the edge of the first alignment block A second trigger piece corresponding to the end point proximity switch is provided. 4 . The scanning beam limiting and collimating mechanism of an X-ray source according to claim 3 , wherein the starting point proximity switch and the first scanning direction limiting block are close to the second scanning direction limiting block. 5 . A first buffer zone is formed between the edges, a second buffer zone is formed between the end point proximity switch and the edge of the second scan direction limit block close to the first scan direction limit block, and the widths of the first buffer zone and the second buffer zone are both equal. greater than the width between the bottoms of the first and second collimation blocks. 5. The scanning beam-limiting and collimating mechanism of an X-ray source according to any one of claims 1-4, wherein the first collimating block, the second collimating block, the first scanning The cross-sections of the search direction limiting block and the second scanning direction limiting block are both fan-shaped rings with the focus of the X-ray tube as the center of the circle, and the scanning driving device drives the first collimating block and the second collimating block to stick to the first scanning block. The upper surfaces of the search-direction limiting block and the second scanning-direction limiting block make circular arc movements with the focus of the X-ray tube as the center of the circle. 6. A scanning control method for a scanning beam limiting and collimating mechanism of an X-ray source, characterized in that it comprises the following steps: S01. Set the running speed of the scanning collimation block according to the exposure parameters of the X-ray source; S02. Trigger the instruction to start scanning, so that the scanning alignment block runs at the set running speed; S03. Control the X-ray ball before the unit light field channel between the first scanning collimation block and the second scanning collimation block enters the effective light field opening between the first scanning direction limiting block and the second scanning direction limiting block The tube starts exposure, and the X-ray tube ends exposure when the unit light field channel leaves the effective light field opening; S04. After the unit light field channel leaves the effective light field opening, the scanning collimation block stops scanning and resets. 7. The scanning control method of a scanning beam limiting and collimating mechanism of an X-ray source according to claim 8, wherein: in the step S01, the scanning and collimating block running speed is according to the formula: Check speed=unit light field width/irradiation time for calculation, and the irradiation time is calculated according to the formula: irradiation time=target current time product/X-ray source tube current. 8. The scanning control method of a scanning beam limiting and collimating mechanism of an X-ray source according to claim 8, wherein in the step S03, before the unit light field channel enters the effective light field opening, the first The first trigger piece at the bottom of the collimation block triggers the starting point proximity switch on the first scanning direction limit block and controls the X-ray tube to start exposure; The second trigger sheet triggers the end-point proximity switch on the second scanning direction limit block and controls the X-ray tube to end exposure accordingly. 9 . The scanning control method of a scanning beam limiting and collimating mechanism of an X-ray source according to claim 9 , wherein: when the scanning and collimating block is reset, the The first trigger piece triggers the first scanning direction limit block and the starting point on the limit block is close to the switch, and then the delay stops.

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