Double-layer multi-leaf grating based on embedded track

Abstract

The invention provides a double-layer multi-leaf grating based on embedded rails, and relates to the technical field of multi-leaf gratings, the double-layer multi-leaf grating comprises a fixed frame, mounting side plates are fixedly mounted on the two sides of the interior of the fixed frame respectively, and two layers of embedded rail mechanisms are mounted at the two ends of the mounting side plates on the two sides respectively; a plurality of upper combined type blades are arranged in the upper-layer embedded track mechanism, and a plurality of lower combined type blades are arranged in the lower-layer embedded track mechanism. Through the embedded track mechanism, the track and the driving mechanism are embedded into the space where the blades are arranged, so that the effective shielding height of the blades can be higher under the same external size, and ray leakage is remarkably reduced. And a larger front end arc radius is allowed to be used due to the higher blade height, so that the penumbra of rays can be reduced, and the sharpness of an irradiation boundary is improved.

Description

Technical Field

[0001] This invention relates to the field of multileaf grating technology, and more specifically, to a double-layer multileaf grating based on an embedded track. Background Technology

[0002] Multileaf gratings are key components in radiotherapy equipment, used to shape the radiation beam by moving the leaflets to conform to the shape of the tumor target area, thereby protecting the surrounding normal tissue.

[0003] The traditional double-layer multi-leaf grating currently has the following technical drawbacks:

[0004] 1. Limited blade height:

[0005] To reduce radiation leakage in non-irradiated areas, the blade height needs to be increased as much as possible to enhance the radiation shielding effect. However, since the drive motor and track are usually located on the outside of the blade, the overall structural space is limited, making it difficult to further increase the blade height. When the blade height is insufficient, a smaller leading edge radius must be used to meet the geometric shielding conditions, which will lead to an increase in penumbra and a wider dose transition zone at the edge of the irradiation field, affecting the sharpness of the dose distribution and the irradiation accuracy.

[0006] 2. Blade processing is complex and costly:

[0007] In traditional gratings, the drive screw needs to pass through the blades, so long holes must be machined on the high-hardness tungsten alloy blades. The large number of blades (usually 80-120) results in a large amount of machining, complex processes, low yield, and high manufacturing costs.

[0008] 3. The overall length of the equipment is large:

[0009] In the traditional layout, the drive motor and track frame are located on the front and rear sides of the blade's movement direction, resulting in the entire grating being too long (up to 700mm) in the blade's forward direction, occupying valuable space in the accelerator head and hindering the compact design of the overall structure.

[0010] Therefore, there is an urgent need in this field for a novel multileaf grating structure that can ensure shielding effectiveness, reduce penumbra, and is compact, easy to manufacture, and inexpensive. Summary of the Invention

[0011] To address the shortcomings of existing technologies, this invention provides a double-layer multi-leaf grating based on an embedded track. Its core objective is to maximize the effective shielding height of the blades within a limited installation space, while reducing the penumbra at the front end; optimize the overall structural layout of the grating, significantly shorten the length of the grating in the blade movement direction, and improve the compactness of the accelerator as a whole.

[0012] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0013] A double-layer multi-leaf grating based on an embedded track includes a fixed frame. Mounting side plates are fixedly installed on both sides of the fixed frame. Two layers of embedded track mechanisms are installed at both ends of the mounting side plates. The upper embedded track mechanism has a number of upper composite blades, and the lower embedded track mechanism has a number of lower composite blades.

[0014] Preferably, the embedded track mechanism includes an arc-shaped seat, and a plurality of sliding groove groups are respectively opened on the upper and lower surfaces of the arc-shaped seat. The adjacent sliding groove groups on both sides are arranged in opposite directions, and the upper and lower sliding groove groups are staggered. Each sliding groove group is distributed in an arc.

[0015] Preferably, the slide rail assembly includes a blade track hole, a motor mounting hole is provided inside the blade track hole, the motor mounting hole is used to fix and install a motor, and a lead screw receiving hole is provided on one side of the motor mounting hole, the lead screw receiving hole is used to set the lead screw for connecting the motor.

[0016] Preferably, a lateral limiting groove is provided on the inner wall of the blade track hole, and a connecting groove is provided between the lead screw receiving hole and the blade track hole.

[0017] Preferably, the upper composite blade adopts a split design, including an upper blade shielding section and an upper blade sliding section. The upper blade shielding section and the upper blade sliding section are fixedly connected. An upper track pair is provided on the inner side of the upper blade sliding section. The upper track pair is interlocked with the track hole of the corresponding upper blade.

[0018] Preferably, the lower side of the upper track is provided with an upper limit protrusion, which is matched with the corresponding lateral limiting groove of the upper layer. The inner side of the upper track is provided with a nut mounting groove for installing the lead screw nut.

[0019] Preferably, the adjacent upper blade shielding sections and upper blade sliding sections are arranged in opposite vertical directions, and the adjacent upper track pairs and upper limit protrusions are arranged at different heights and are staggered.

[0020] Preferably, the lower composite blade adopts a split design, including a lower blade shielding section and a blade sliding section. The lower blade shielding section and the lower blade sliding section are fixedly connected. The lower blade sliding section is provided with a lower track pair inside, and the lower track pair is interlocked with the corresponding lower blade track hole.

[0021] Preferably, a lower limit protrusion is provided on the lower side of the lower track pair, and the lower limit protrusion is matched with the corresponding lateral limit groove of the lower layer. A nut mounting groove for installing the lead screw nut is provided on the inner side of the lower track pair.

[0022] Preferably, the adjacent lower track pairs are arranged in opposite directions.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. High space utilization and good shielding performance:

[0025] Embedded design: The track and drive mechanism are embedded in the space where the blades are arranged, rather than placed in front of or behind the blades. This allows the effective shielding height of the blades to be greater with the same external dimensions, thereby significantly reducing radiation leakage.

[0026] Penumbra optimization: Higher blade height allows for the use of a larger leading edge radius, which in turn helps to reduce the penumbra of the rays and improves the sharpness of the irradiation boundary.

[0027] 2. Simplified structure and significantly reduced costs:

[0028] No need for elongated holes in the blades: The drive screw no longer needs to pass through the blade body, thus completely avoiding the problem of machining elongated holes in high-hardness tungsten alloy blades, greatly simplifying the blade machining process and improving production efficiency and yield.

[0029] Material cost optimization: The composite blade design uses expensive tungsten alloy only in the critical shielding area at the front end, while the sliding structure at the rear end uses inexpensive steel, effectively reducing raw material costs.

[0030] 3. Compact overall layout:

[0031] Space reuse: The embedded track mechanism allows the drive motor to share space with the blades in the direction of blade movement, rather than occupying additional space. This design can reduce the overall length of the grating by about 100mm, which is of great value for radiotherapy equipment that pursues miniaturization and compactness.

[0032] 4. Stable and reliable operation:

[0033] The composite guiding system, consisting of the blade track hole and the lateral limiting groove, ensures the stability and straightness of the blade during high-speed, high-precision movement, preventing tipping and swaying. Attached Figure Description

[0034] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0035] Figure 2 This is a three-dimensional structural schematic diagram from another perspective of the present invention;

[0036] Figure 3 This is a front view structural diagram of the present invention;

[0037] Figure 4 This is a side view of the structure of the present invention;

[0038] Figure 5 It is a three-dimensional structural diagram of a fixed frame;

[0039] Figure 6 This is a side view of the fixed frame structure.

[0040] Figure 7 yes Figure 6 Schematic diagram of the cross-sectional structure at point AA;

[0041] Figure 8 yes Figure 6 Schematic diagram of the cross-sectional structure at point BB;

[0042] Figure 9 This is a three-dimensional structural diagram of the upper composite blade;

[0043] Figure 10 This is a partial three-dimensional structural diagram of the upper composite blade;

[0044] Figure 11 This is a partial side view of the composite blade structure.

[0045] Figure 12 This is a three-dimensional structural diagram of a composite blade.

[0046] Figure 13 This is a partial three-dimensional structural diagram of the composite blade.

[0047] Figure 14 This is a partial side view of the composite blade structure.

[0048] In the diagram: 1. Fixed frame; 2. Mounting side plate; 3. Embedded track mechanism; 301. Arc-shaped seat; 302. Connecting groove; 303. Motor mounting hole; 304. Lateral limiting groove; 305. Screw receiving hole; 306. Blade track hole; 307. Slide assembly; 4. Upper composite blade; 401. Upper blade shielding section; 402. Upper blade sliding section; 403. Upper track pair; 404. Upper limit protrusion; 5. Lower composite blade; 501. Lower blade shielding section; 502. Lower blade sliding section; 503. Lower track pair; 504. Lower limit protrusion; 6. Nut mounting groove. Detailed Implementation

[0049] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0050] like Figures 1 to 14 As shown, a double-layer multi-leaf grating based on an embedded track includes a fixed frame 1. Mounting side plates 2 are fixedly installed on both sides inside the fixed frame 1. Two layers of embedded track mechanisms 3 are installed at both ends of the mounting side plates 2. The upper embedded track mechanism 3 is provided with a number of upper composite blades 4, and the lower embedded track mechanism 3 is provided with a number of lower composite blades 5.

[0051] In this embodiment, the embedded track mechanism 3 includes an arc-shaped seat 301. Several sliding groove groups 307 are respectively opened on the upper and lower surfaces of the arc-shaped seat 301. The adjacent sliding groove groups 307 on both sides are arranged oppositely, and the upper and lower sliding groove groups 307 are staggered. Each sliding groove group 307 is distributed in an arc.

[0052] It should be noted that the slide rail assembly 307 includes a blade track hole 306, a motor mounting hole 303 is provided inside the blade track hole 306, the motor mounting hole 303 is used to fix and install the motor, and a lead screw receiving hole 305 is provided on one side of the motor mounting hole 303, the lead screw receiving hole 305 is used to set the lead screw for motor connection.

[0053] The blade track hole 306 has a lateral limiting groove 304 on its inner wall, and a connecting groove 302 is provided between the screw receiving hole 305 and the blade track hole 306.

[0054] By integrating the motor mounting hole 303 and the lead screw receiving hole 305 inside the blade track hole 306, the space occupied by the motor can be reduced, thereby reducing the overall volume of this application and making it more compact. Furthermore, the embedded fit between the blade track hole 306 and the blade further reduces the volume and improves the effective shielding performance of the blade. The lateral limiting groove 304 can be used to limit the lateral sway of the blade during movement.

[0055] In this application, the upper composite blade 4 adopts a split design, including an upper blade shielding section 401 and an upper blade sliding section 402. The upper blade shielding section 401 and the upper blade sliding section 402 are fixedly connected. An upper track pair 403 is provided on the inner side of the upper blade sliding section 402. The upper track pair 403 is interlocked with the upper blade corresponding track hole 306.

[0056] In the specific configuration, an upper limit protrusion 404 is provided on the lower side of the upper track pair 403. The upper limit protrusion 404 is matched with the corresponding lateral limit groove 304 on the upper layer. A nut mounting groove 6 for installing the lead screw nut is opened on the inner side of the upper track pair 403.

[0057] Among them, the adjacent upper blade shielding section 401 and the upper blade sliding section 402 are arranged in opposite directions, and the adjacent upper track pair 403 and the upper limit protrusion 404 are arranged at different heights and are staggered.

[0058] In this application, the lower composite blade 5 adopts a split design, including a lower blade shielding section 501 and a lower blade sliding section 502. The lower blade shielding section 501 and the lower blade sliding section 502 are fixedly connected. The lower blade sliding section 502 is provided with a lower track pair 503 inside. The lower track pair 503 is interlocked with the corresponding lower blade track hole 306.

[0059] In the specific configuration, a lower limit protrusion 504 is provided on the lower side of the lower track pair 503. The lower limit protrusion 504 is matched with the corresponding lateral limit groove 304 in the lower layer. A nut mounting groove 6 for installing the lead screw nut is opened on the inner side of the lower track pair 503.

[0060] Among them, the adjacent lower track sub-503 are arranged in opposite directions.

[0061] By using adjacent upper track pairs 403 and upper limit protrusions 404 at different and staggered heights, and by using adjacent lower track pairs 503 arranged in opposite directions, the protruding parts can be staggered to avoid them colliding and occupying too much space. This allows the present application to use the blade track hole 306 and the lateral limiting groove 304 to reduce the width occupied by multiple blades after the distribution of several upper composite blades 4 and lower composite blades 5, reduce the spacing between each blade, make it more compact, thereby significantly reducing radiation leakage and also making the volume smaller.

[0062] It should be noted that the embedded track mechanism 3 can be made of high-strength aluminum alloy or steel through precision machining. The drive motor used during installation is preferably a servo motor, precisely installed within the motor mounting hole 303. The lead screw is a precision ball screw, with one end connected to the motor output shaft and the other end supported by a bearing.

[0063] The manufacturing process of the composite blade is as follows: First, the "C"-shaped front shielding section of tungsten alloy and the rear sliding section of steel are machined separately; then, the two are positioned using precision tooling and connected using high-performance welding processes such as electron beam welding or laser welding; finally, the welded composite blade is precision machined to ensure the dimensional accuracy of the track pair and the limiting surface.

[0064] During blade assembly, the cylindrical track assembly of its rear sliding section is inserted into the blade track hole 306 of the embedded track mechanism 3, while the limiting protrusion on the side of the blade is engaged in the lateral limiting groove 304 of the embedded track mechanism 3. The nut on the lead screw is installed in the nut mounting groove 6 of the sliding section. In this way, the motor drives the lead screw to rotate, which in turn drives the nut to move linearly, thereby driving the entire blade to slide smoothly and precisely within the embedded track mechanism.

[0065] Through the above design, the present invention successfully achieves the comprehensive goals of high shielding, low penumbra, compact structure, low cost and high reliability.

[0066] Each upper composite blade 4 and lower composite blade 5 employs a split design, comprising two parts: front and rear.

[0067] Forward shielding section: Located at the leading edge of the blade, it is made of high-density shielding material (such as tungsten alloy). Its cross-section is C-shaped, with the leading edge machined into an arc shape to reduce the penumbra. This part is the main shielding structure and is responsible for blocking rays.

[0068] Rear sliding section: Located at the rear end of the blade, it cooperates with the embedded track mechanism 3. This part is made of materials with good mechanical properties and low cost, such as ordinary steel. Its rear part is hollowed out to form a rectangular opening to reduce weight.

[0069] The front shielding section and the rear sliding section are fixedly connected as one unit by welding or other methods.

[0070] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is impossible to exhaustively list all the implementation methods here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.

Claims

1. A double-layered multi-leaf optical grating based on embedded tracks, comprising a fixed frame (1), characterized in that: The fixed frame (1) is internally fixedly installed with installation side plates (2) on both sides, both ends of the installation side plates (2) are respectively installed with two layers of embedded track mechanisms (3), a plurality of upper composite blades (4) are arranged in the upper embedded track mechanism (3), and a plurality of lower composite blades (5) are arranged in the lower embedded track mechanism (3).

2. A double layered multi leaf collimator based on in-line type of orbit according to claim 1, wherein: The embedded track mechanism (3) comprises an arc-shaped seat (301), a plurality of slide groove groups (307) are formed in the upper and lower surfaces of the arc-shaped seat (301), and the slide groove groups (307) are oppositely arranged between two adjacent slide groove groups (307) on both sides.

3. A double layered multi leaf collimator based on in-line type of the track according to claim 2, characterized in that: The slide groove group (307) comprises a blade track hole (306), a motor mounting hole (303) is formed in the blade track hole (306), a motor is fixedly installed in the motor mounting hole (303), a screw rod containing hole (305) is formed in one side of the motor mounting hole (303), and a screw rod connected with the motor is arranged in the screw rod containing hole (305).

4. A double layered multi leaf collimator based on in-line type of the track according to claim 3, characterized in that: A lateral limiting groove (304) is formed in the inner wall of the blade track hole (306), and a communication groove (302) is formed between the screw rod containing hole (305) and the blade track hole (306).

5. A double layered multi leaf collimator based on in-line type of the track according to claim 4, characterized in that: The upper composite blade (4) is designed in a split type and comprises an upper blade shielding section (401) and an upper blade sliding section (402), the upper blade shielding section (401) is fixedly connected with the upper blade sliding section (402), an upper track pair (403) is arranged on the inner side of the upper blade sliding section (402), and the upper track pair (403) is insertedly matched with the upper corresponding blade track hole (306).

6. A double layered multi leaf collimator based on in-line type of the track according to claim 5, characterized in that: An upper limiting protrusion (404) is arranged on the lower side of the upper track pair (403), the upper limiting protrusion (404) is limitingly matched with the upper corresponding lateral limiting groove (304), and a nut mounting groove (6) for mounting a screw rod nut is formed in the inner side of the upper track pair (403).

7. A double layered multi leaf collimator based on in-line type of the track according to claim 6, characterized in that: The upper blade shielding section (401) and the upper blade sliding section (402) are oppositely arranged in an upper and lower manner, the heights of the upper track pair (403) and the upper limiting protrusion (404) are different and the upper track pair (403) and the upper limiting protrusion (404) are arranged in an interlaced manner.

8. A double layered multi leaf collimator based on in-line type of the track according to claim 4, characterized in that: The lower composite blade (5) is designed in a split type and comprises a lower blade shielding section (501) and a lower blade sliding section (502), the lower blade shielding section (501) is fixedly connected with the lower blade sliding section (502), a lower track pair (503) is arranged in the lower blade sliding section (502), and the lower track pair (503) is insertedly matched with the lower corresponding blade track hole (306).

9. A double layered multi leaf collimator based on in-line type of the track according to claim 8, characterized in that: A lower limiting protrusion (504) is arranged on the lower side of the lower track pair (503), the lower limiting protrusion (504) is limitingly matched with the lower corresponding lateral limiting groove (304), and a nut mounting groove (6) for mounting a screw rod nut is formed in the inner side of the lower track pair (503).

10. A double layered multi leaf collimator based on in-line type of the track according to claim 9, characterized in that: The lower track pairs (503) are oppositely arranged in an upper and lower manner.

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