Radiotherapy radiation field adjusting device

Abstract

The invention relates to a radiation therapy radiation field adjusting device, and relates to the radiation therapy technology field, the radiation therapy radiation field adjusting device comprises a bottom plate, a top cover, a first adjusting assembly and a second adjusting assembly, the upper surface of the bottom plate is fixedly connected with the top cover, a cavity is formed between the bottom plate and the top cover, and the bottom plate and the top cover are respectively provided with a window; the first adjusting assembly and the second adjusting assembly are located in the cavity, and the first adjusting assembly and the second adjusting assembly are completely the same in structure and are perpendicular to each other. The corresponding blades can be driven to move only by driving the worm on the first adjusting assembly or the second adjusting assembly to rotate, the distance between the blades is adjusted independently, adjustment is more flexible, meanwhile, by means of the self-locking characteristic of the worm wheel and the worm, the worm wheel cannot drive the worm to rotate, only the worm wheel drives the lead screw to rotate, and therefore adjustment is more convenient. The positions of the blades can be fixed after the blades are adjusted, movement is avoided, the distance between the blades is prevented from changing, and the treatment effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of radiotherapy, and in particular to a radiotherapy field adjustment device. Background Art

[0002] Grid therapy and lattice therapy are two technical means of spatially fractionated radiotherapy, mainly used for treating large-volume tumors. Grid therapy is a two-dimensional radiotherapy technique that evenly divides the irradiation field into equally spaced small beamlets through a grid collimator or by using a multi-leaf collimator, and can form a discontinuous high-dose distribution on the tumor at a certain interval, while keeping the normal tissues around the tumor receiving a lower dose of irradiation to avoid related toxicities.

[0003] During the treatment process, these beamlets will form non-uniform high- and low-dose regions within the tumor target area, namely high-dose regions (peaks) and low-dose regions (valleys). This dosimetric peak-valley effect helps protect normal tissues. Grid therapy is usually used for single large-dose irradiation (10 - 25 Gy) and is suitable for palliative treatment of advanced large tumors. Lattice therapy is a three-dimensional extension of grid therapy and is a more advanced technique. It creates multiple spherically shaped high-dose regions distributed in a lattice pattern in space within the tumor volume through three-dimensional focusing technology. There is a certain distance between these high-dose regions, forming an obvious peak-valley dose distribution. Compared with two-dimensional grid therapy, lattice therapy can produce a more significant peak-valley effect and reduce the dose of normal tissues around the tumor to a greater extent. In addition, lattice therapy can also stimulate the bystander effect and immunogenic abscopal effect, enhancing the killing ability of tumor cells.

[0004] Currently, grid and lattice therapies have been clinically applied, mainly realized through physical grids or MLCs. Lattice therapy relies more on computer models and advanced three-dimensional focusing technology. Both of these technologies belong to spatially fractionated radiotherapy. By forming high-dose and low-dose regions within the tumor, the treatment effect on large-volume tumors has been effectively improved, while reducing the damage to surrounding normal tissues. However, the existing multi-leaf collimator needs to adjust the spacing of each leaf through multiple micro-motors, with a complex structure. Moreover, the leaves are not fixed in position after adjustment and are prone to movement, resulting in changes in the leaf spacing and affecting the treatment effect. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing multi-leaf collimator needs to adjust the spacing of each leaf through multiple micro-motors, with a complex structure. Moreover, the leaves are not fixed in position after adjustment and are prone to movement, resulting in changes in the leaf spacing and affecting the treatment effect.

[0006] To solve the above technical problems, the present invention provides the following technical solution: A radiotherapy field adjustment device, which includes a bottom plate, a top cover, a first adjustment component and a second adjustment component. The upper surface of the bottom plate is fixedly connected to the top cover, and a cavity is formed between the bottom plate and the top cover. Windows are respectively opened on the bottom plate and the top cover. The first adjustment component and the second adjustment component are located inside the cavity. The first adjustment component and the second adjustment component have exactly the same structure and are perpendicular to each other. The first adjustment component and the second adjustment component respectively include an arc-shaped guide rail, blades, support rods and arc-shaped sliders. Both ends of the blades are respectively fixedly connected to one side of two arc-shaped sliders, and the other side of the two arc-shaped sliders is fixedly connected to both ends of the support rod. Multiple groups of arc-shaped grooves are opened on the arc-shaped guide rail, and the inner walls of each group of arc-shaped grooves are respectively connected to the arc-shaped sliders. The support rod is fixedly connected to a sleeve, the sleeve is threadedly connected to one end of a lead screw, the other end of the lead screw is fixedly connected to a worm gear, and the worm gear is meshed with a worm.

[0007] As a preferred solution of the radiotherapy field adjustment device described in the present invention, it further includes a drive component, which includes a drive shaft, a first gear, a second gear, a synchronous toothed belt and a rotating shaft. The drive shaft is fixedly connected to the first gear, the first gear is meshed with the inner side of one end of the synchronous toothed belt, the inner side of the other end of the synchronous toothed belt is meshed with the second gear, the second gear is connected to the rotating shaft, and the rotating shaft fixedly connected passes through the axis of the worm.

[0008] As a preferred solution of the radiotherapy field adjustment device described in the present invention, a card slot is opened on the inner side of the second gear, a first accommodation cavity and a chute are opened on the rotating shaft, the first accommodation cavity communicates with the chute, an electromagnet is fixedly connected to the bottom wall of the first accommodation cavity, an iron block is slidably connected to the inner wall of the first accommodation cavity, one end of a clamping block is fixedly connected to the iron block, the clamping block is slidably connected to the inner wall of the chute, the other end of the clamping block faces the card slot, and one end of a first tension spring is fixedly connected to the iron block, and the other end of the first tension spring is fixedly connected to the top wall of the first accommodation cavity.

[0009] As a preferred solution of the radiotherapy field adjustment device described in the present invention, the other end of the clamping block faces the card slot.

[0010] As a preferred solution of the radiotherapy field adjustment device described in the present invention, limiting rings are fixedly connected to the rotating shaft on both sides of the second gear, and the second gear is slidably connected to the limiting rings on both sides.

[0011] As a preferred solution of the radiotherapy field adjustment device described in the present invention, a third gear is meshed with the inner side of the synchronous toothed belt. A core shaft is fixedly connected to the axis of the third gear. Both ends of the core shaft are respectively rotatably connected to the inner wall of a sleeve. One end of a second tension spring is fixedly connected to the outer wall of the sleeve, and the other end of the second tension spring is hinged to a fixed seat.

[0012] As a preferred embodiment of the radiation therapy field adjustment device of the present invention, the following is provided: a through groove is formed on the fixed seat, limiting grooves are formed on both sides of the through groove, a limiting block is slidably connected to the inner wall of the limiting groove, both ends of the rotating shaft are respectively rotatably connected to the limiting block, the limiting block is fixedly connected to the movable block, and the smooth section of the lead screw is rotatably connected and passes through the movable block.

[0013] As a preferred embodiment of the radiation therapy field adjustment device of the present invention, the following is provided: the bottom of the arc-shaped guide rail is fixedly connected to the mounting seat, the mounting seat is fixedly connected to the bottom plate, and a reinforcing rod is fixedly connected between two corresponding arc-shaped guide rails.

[0014] As a preferred embodiment of the radiation therapy field adjustment device of the present invention, the following is provided: one end of the driving shaft is fixedly connected to the motor, and the motor is fixedly connected to the bottom plate through the motor seat.

[0015] As a preferred embodiment of the radiation therapy field adjustment device of the present invention, the following is provided: the other end of the driving shaft is connected to one end of the connecting rod through a universal joint, and the other end of the connecting rod is connected to the driving shaft on the second adjustment component through another universal joint.

[0016] Advantages of the present invention: The present invention only needs to drive the worm on the first adjustment component or the second adjustment component to rotate, which can respectively drive the corresponding blades to move, individually adjust the spacing between each blade, and the adjustment is more flexible; At the same time, by utilizing the self-locking characteristics of the worm gear and the worm, the worm gear cannot drive the worm to rotate. Only the worm gear can drive the lead screw to rotate, which can fix the position of the blade after adjustment, prevent movement, prevent the change of the blade spacing, and is beneficial to improving the treatment effect. Description of the Drawings

[0017] Figure 1 It is a schematic diagram of the overall structure in the embodiment of the present disclosure.

[0018] Figure 2 It is a schematic diagram of the arc-shaped guide rail structure in the embodiment of the present disclosure.

[0019] Figure 3 It is a schematic diagram of the blade structure in the embodiment of the present disclosure.

[0020] Figure 4 It is a schematic diagram of the arc-shaped slider structure in the embodiment of the present disclosure.

[0021] Figure 5 It is in the embodiment of the present disclosure Figure 1 The enlarged schematic diagram at position A.

[0022] Figure 6 It is a cross-sectional view of the second gear in the embodiment of the present disclosure.

[0023] Figure 7 The sectional view of the rotating shaft in the embodiment of the present disclosure.

[0024] Figure 8 The schematic connection diagram of the drive shaft and the connecting rod in the embodiment of the present disclosure.

[0025] Reference numerals: base plate 1, top cover 2, first adjusting component 3, second adjusting component 4, window 5, arc-shaped guide rail 31, arc-shaped groove 311, mounting seat 312, strengthening rod 313, blade 32, support rod 33, sleeve 331, lead screw 332, worm gear 333, worm 334, arc-shaped slider 34, drive component 6, drive shaft 61, motor 611, motor base 612, universal joint 614, connecting rod 615, first gear 62, second gear 63, card slot 631, limiting ring 632, synchronous toothed belt 64, rotating shaft 65, first accommodating cavity 651, chute 652, electromagnet 653, iron block 654, clamping block 655, first tension spring 656, third gear 66, core shaft 661, sleeve 662, second tension spring 663, fixed seat 664, through slot 665, movable block 666, limiting slot 667, limiting block 668. Detailed implementation manners

[0026] In order to make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific implementation manners of the present invention will be given in conjunction with the accompanying drawings of the specification.

[0027] Example 1, referring to Figures 1-5 , this embodiment provides a radiotherapy field adjustment device, including a base plate 1, a top cover 2, a first adjusting component 3 and a second adjusting component 4. The upper surface of the base plate 1 is fixedly connected to the top cover 2, a cavity is formed between the base plate 1 and the top cover 2, windows 5 are respectively opened on the base plate 1 and the top cover 2, the first adjusting component 3 and the second adjusting component 4 are located inside the cavity, the structures of the first adjusting component 3 and the second adjusting component 4 are completely the same and are perpendicular to each other.

[0028] Preferably in this embodiment, the cavity is used to accommodate the cavity, and the ray can irradiate the tumor through the windows 5 of the base plate 1 and the top cover 2, so as to perform treatment. The window 5 is a direction, two groups of the first adjusting component 3 and the second adjusting component 4 are respectively provided, and one group of the first adjusting component 3 is symmetrically arranged with the other group of the first adjusting component 3, and are respectively located on both sides of the window 5, and one group of the second adjusting component 4 is symmetrically arranged with the other group of the second adjusting component 4, and are respectively located on both sides of the window 5.

[0029] The first adjustment component 3 and the second adjustment component 4 respectively include an arc-shaped guide rail 31, a blade 32, a support rod 33 and an arc-shaped slider 34. Both ends of the blade 32 are respectively fixedly connected to one side of two arc-shaped sliders 34. The other sides of the two arc-shaped sliders 34 are fixedly connected to both ends of the support rod 33. A plurality of groups of arc-shaped grooves 311 are formed on the arc-shaped guide rail 31. The inner walls of each group of arc-shaped grooves 311 are respectively connected to the arc-shaped slider 34. The support rod 33 is fixedly connected to a sleeve 331. One end of the sleeve 331 is threadedly connected to one end of a lead screw 332. The other end of the lead screw 332 is fixedly connected to a worm gear 333. The worm gear 333 is meshed and connected to a worm 334.

[0030] Preferably in this embodiment, the use of the arc-shaped guide rail 31 is beneficial to improving the load-bearing capacity of the guide rail, enabling it to withstand large loads and impact forces, and remaining stable even under high-speed movement. The arc-shaped guide rails 31 on the first adjustment component 3 and the second adjustment component 4 are respectively provided with five arc-shaped grooves 311. The inner walls of each group of arc-shaped grooves 311 are respectively connected to the arc-shaped slider 34. When the worm 334 rotates, it can drive the worm gear 333. When the worm gear 333 rotates, it can drive the lead screw 332 to rotate. Under the action of the thread, the lead screw 332 drives the sleeve 331 to move along the length direction of the lead screw 332. When the sleeve 331 moves, it can drive the support rod 33 to move. When the support rod 33 moves, it can drive the arc-shaped slider 34 to move. The arc-shaped slider 34 drives the blade 32 to move, adjusting the distance between each blade 32. Moreover, only by driving the worm 334 on the first adjustment component 3 or the second adjustment component 4 to rotate can the corresponding blade 32 be driven to move respectively, independently adjusting the distance between each blade 32, and the adjustment is more flexible. At the same time, by utilizing the self-locking characteristics of the worm gear 333 and the worm 334, the worm gear 333 cannot drive the worm 334 to rotate. Only the worm gear 333 can drive the lead screw 332 to rotate, which can fix the position of the blade after adjustment, avoid movement, prevent the change of the blade distance, and is beneficial to improving the treatment effect.

[0031] Example 2, referring to Figures 1-8 , this embodiment is based on the previous embodiment, and the difference from the previous embodiment is as follows.

[0032] Referring to Figure 5 , it further includes a driving component 6. The driving component 6 includes a driving shaft 61, a first gear 62, a second gear 63, a synchronous toothed belt 64 and a rotating shaft 65. The driving shaft 61 is fixedly connected to the first gear 62. The first gear 62 is meshed and connected to the inner side of one end of the synchronous toothed belt 64. The inner side of the other end of the synchronous toothed belt 64 is meshed and connected to the second gear 63. The second gear 63 is connected to the rotating shaft 65. The rotating shaft 65 is fixedly connected and passes through the axis of the worm 334.

[0033] Preferably, in this embodiment, when the drive shaft 61 rotates, it can drive the first gear 62 to rotate. The first gear 62 drives the second gear 63 to rotate through the synchronous toothed belt 64, and then drives the rotating shaft 65 to rotate. The rotating shaft 65 drives the worm 334 to rotate. When the worm 334 rotates, it can drive the worm gear 333. When the worm gear 333 rotates, it can drive the lead screw 332 to rotate. Under the action of the thread, the lead screw 332 drives the sleeve 331 to move along the length direction of the lead screw 332. When the sleeve 331 moves, it can drive the support rod 33 to move. When the support rod 33 moves, it can drive the arc-shaped slider 34 to move. The arc-shaped slider 34 drives the blade 32 to move, adjusting the distance between the blades 32.

[0034] Referring to Figure 6 and Figure 7 , a clamping groove 631 is formed inside the second gear 63. A first accommodation cavity 651 and a sliding groove 652 are formed on the rotating shaft 65. The first accommodation cavity 651 communicates with the sliding groove 652. An electromagnet 653 is fixedly connected to the bottom wall of the first accommodation cavity 651. An iron block 654 is slidably connected to the inner wall of the first accommodation cavity 651. One end of a clamping block 655 is fixedly connected to the iron block 654. The clamping block 655 is slidably connected to the inner wall of the sliding groove 652. One end of a first tension spring 656 is fixedly connected to the iron block 654, and the other end of the first tension spring 656 is fixedly connected to the top wall of the first accommodation cavity 651. The clamping grooves 631 are arranged in an annular array inside the second gear 63. During installation, the rotating shaft 65 is cut along the Figure 7 shown cross-section. When the internal structures of the first accommodation cavity 651 and the sliding groove 652 are installed, the cut rotating shaft 65 is welded together to form a complete rotating shaft 65.

[0035] Preferably, in this embodiment, under the pulling force of the first tension spring 656, the iron block 654 is pulled upward in the Figure 7 . The iron block 654 drives the clamping block 655 to move. The clamping block 655 can slide on the inner wall of the sliding groove 652. When the other end of the clamping block 655 is inserted into the clamping groove 631, at this time, when the rotating shaft 65 rotates, it can drive the worm 334 to rotate. When the electromagnet 653 is energized, the electromagnet 653 generates a magnetic force to attract the iron block 654, and the iron block 654 drives the iron block 654 to move downward in the Figure 7 . At this time, the clamping block 655 disengages from the clamping groove 631, and at this time, when the rotating shaft 65 rotates, it cannot drive the worm 334.

[0036] Referring to Figure 5 , the other end of the clamping block 655 faces the clamping groove 631.

[0037] Preferably, in this embodiment, under the pulling force of the first tension spring 656, the iron block 654 is pulled upward in the Figure 7When moving upward in it, the iron block 654 drives the clamping block 655 to move. The clamping block 655 can slide on the inner wall of the chute 652, and the other end of the clamping block 655 faces the card slot 631 so that the other end of the clamping block 655 can be inserted into the card slot 631.

[0038] Refer to Figure 6 and Figure 7 , on the rotating shafts 65 on both sides of the second gear 63, limiting rings 632 are fixedly connected, and the limiting rings 632 are slidably connected to both sides of the second gear 63.

[0039] Preferably in this embodiment, under the action of the limiting ring 632, the second gear 63 is prevented from moving along the length direction of the rotating shaft 65, resulting in the second gear 63 being disengaged from the synchronous toothed belt 64.

[0040] Refer to Figure 5 , the inner side of the synchronous toothed belt 64 is meshed and connected to the third gear 66. The core shaft 661 is fixedly connected to the center of the third gear 66. The two ends of the core shaft 661 are respectively rotatably connected to the inner wall of the sleeve 662. One end of the second tension spring 663 is fixedly connected to the outer wall of the sleeve 662, and the other end of the second tension spring 663 is hinged and connected to the fixed seat 664.

[0041] Preferably in this embodiment, when the synchronous toothed belt 64 rotates, it can drive the third gear 66 to rotate. The third gear 66 drives the core shaft 661 to rotate. The core shaft 661 rotates relative to the sleeve 662 on the inner wall of the sleeve 662, and the second tension spring 663 can keep the synchronous toothed belt 64 always taut under the action of the pulling force.

[0042] Refer to Figure 5 , a through groove 665 is formed in the fixed seat 664. Limiting grooves 667 are formed on both sides of the through groove 665. The inner wall of the limiting groove 667 is slidably connected to the limiting block 668. The two ends of the rotating shaft 65 are respectively rotatably connected to the limiting block 668. The limiting block 668 is fixedly connected to the movable block 666. The smooth section of the lead screw 332 is rotatably connected and passes through the movable block 666.

[0043] Preferably in this embodiment, the limiting block 668 can slide on the inner wall of the limiting groove 667. The smooth section of the lead screw 332 is rotatably connected and passes through the movable block 666, which can limit the position of the lead screw 332, and the lead screw 332 can rotate inside the movable block 666.

[0044] Refer to Figure 3 , the bottom of the arc-shaped guide rail 31 is fixedly connected to the mounting seat 312. The mounting seat 312 is fixedly connected to the bottom plate 1. A reinforcing rod 313 is fixedly connected between two corresponding arc-shaped guide rails 31.

[0045] Preferably, in this embodiment, the corresponding arc-shaped guide rails 31 refer to two groups of symmetrically arranged arc-shaped guide rails 31 on the first adjustment assembly 3 and the second adjustment assembly 4. A reinforcing rod 313 is fixedly connected between the two corresponding arc-shaped guide rails 31, which is beneficial to improving the structural strength between the arc-shaped guide rails 31 and enhancing the stability of the structure.

[0046] Referring to Figure 5 , one end of the drive shaft 61 is fixedly connected to the motor 611, and the motor 611 is fixedly connected to the bottom plate 1 through the motor base 612. Preferably, in this embodiment, the motor 611 can drive the drive shaft 61 to rotate when it works.

[0047] Referring to Figure 8 , the other end of the drive shaft 61 is connected to one end of the connecting rod 615 through a universal joint 614, and the other end of the connecting rod 615 is connected to the drive shaft 61 on the second adjustment assembly 4 through another universal joint 614 Preferably, in this embodiment, the drive shaft 61 on the first adjustment assembly 3 can drive the connecting rod 615 to rotate through the universal joint 614, and the connecting rod 615 drives the drive shaft 61 on the second adjustment assembly 4 to rotate through another universal joint 614.

[0048] Working principle: Only one motor 611 is used to drive the drive shaft 61 to rotate, which can drive all the drive shafts 61 to rotate. When the drive shaft 61 rotates, it can drive the first gear 62 to rotate. The first gear 62 drives the second gear 63 to rotate through the synchronous toothed belt 64. The second gear 63 drives the rotating shaft 65 to rotate, and the rotating shaft 65 drives the worm 334 to rotate. When the worm 334 rotates, it can drive the worm wheel 333. When the worm wheel 333 rotates, it can drive the lead screw 332 to rotate. Under the action of the thread, the lead screw 332 drives the sleeve 331 to move along the length direction of the lead screw 332. When the sleeve 331 moves, it can drive the support rod 33 to move. When the support rod 33 moves, it can drive the arc-shaped slider 34 to move, and the arc-shaped slider 34 drives the blade 32 to move, adjusting the distance between the blades 32.

[0049] When the electromagnet 653 is energized, the electromagnet 653 generates a magnetic force to attract the iron block 654, and the iron block 654 drives the iron block 654 towards Figure 7Move downward in it. At this time, the clamping block 655 disengages from the clamping groove 631. At this time, the rotation of the rotating shaft 65 cannot drive the worm 334. It can flexibly control whether the clamping block 655 disengages from the clamping groove 631 and whether the second gear 63 drives the rotating shaft 65 to rotate. Furthermore, the worm wheel 333 and the worm 334 can be controlled respectively, and the positions of the blades 32 can be adjusted respectively. It is more flexible to use. At the same time, the position of the blade 32 can be fixed after adjustment to avoid movement and prevent the change of the blade spacing, which is beneficial to improving the treatment effect. Moreover, only one motor 611 is used to drive the drive shaft 61 to rotate, which can drive all the drive shafts 61 to rotate. The structure is simpler and there is no need to use multiple micro motors, which is beneficial to reducing costs.

Claims

1. A radiation therapy field adjustment device, characterized in that: The device comprises a bottom plate (1), a top cover (2), a first adjustment component (3) and a second adjustment component (4); the top cover (2) is fixedly connected to the upper surface of the bottom plate (1); a cavity is formed between the bottom plate (1) and the top cover (2); windows (5) are respectively provided on the bottom plate (1) and the top cover (2); the first adjustment component (3) and the second adjustment component (4) are located inside the cavity; the first adjustment component (3) and the second adjustment component (4) are completely identical in structure and are perpendicular to each other; The first adjustment component (3) and the second adjustment component (4) respectively comprise an arc-shaped guide rail (31), a blade (32), a support rod (33) and an arc-shaped slider (34); two ends of the blade (32) are respectively fixedly connected to one side of two arc-shaped sliders (34); the other sides of the two arc-shaped sliders (34) are respectively fixedly connected to two ends of the support rod (33); a plurality of groups of arc-shaped grooves (311) are provided on the arc-shaped guide rail (31); the inner wall of each group of arc-shaped grooves (311) is respectively connected to the arc-shaped slider (34); The support rod (33) is fixedly connected to the sleeve (331), the sleeve (331) is threadedly connected to one end of the screw rod (332), the other end of the screw rod (332) is fixedly connected to the worm wheel (333), and the worm wheel (333) is meshingly connected to the worm (334).

2. A radiation therapy field adjustment device as claimed in claim 1, characterized in that: The invention also includes a driving assembly (6), wherein the driving assembly (6) includes a driving shaft (61), a first gear (62), a second gear (63), a synchronous toothed belt (64) and a rotating shaft (65), wherein the driving shaft (61) is fixedly connected to the first gear (62), the first gear (62) is meshedly connected to the inner side of one end of the synchronous toothed belt (64), the inner side of the other end of the synchronous toothed belt (64) is meshedly connected to the second gear (63), the second gear (63) is connected to the rotating shaft (65), and the rotating shaft (65) is fixedly connected and passes through the axis of the worm (334).

3. A radiation therapy field adjustment device as claimed in claim 2, characterized in that: A slot (631) is provided on the inner side of the second gear (63), a first accommodating chamber (651) and a slide slot (652) are provided on the rotating shaft (65), the first accommodating chamber (651) is connected to the slide slot (652), the bottom wall of the first accommodating chamber (651) is fixedly connected to the electromagnet (653), the inner wall of the first accommodating chamber (651) is slidably connected to an iron block (654), the iron block (654) is fixedly connected to one end of a block (655), the block (655) is slidably connected to the inner wall of the slide slot (652), the other end of the block (655) faces the slot (631), and the iron block (654) is fixedly connected to one end of a first tension spring (656), the other end of the first tension spring (656) is fixedly connected to the top wall of the first accommodating chamber (651).

4. A radiation therapy field adjustment device as claimed in claim 3, characterized in that: The other end of the card block (655) faces the card slot (631).

5. A radiation therapy field adjustment device as claimed in claim 4, characterized in that: The rotating shafts (65) on both sides of the second gear (63) are fixedly connected to the limiting rings (632), and the limiting rings (632) are slidably connected to both sides of the second gear (63).

6. A radiation therapy field adjustment device as claimed in claim 5, characterized in that: The inner side of the synchronous toothed belt (64) is meshedly connected to the third gear (66); the axis of the third gear (66) is fixedly connected to the core shaft (661); the two ends of the core shaft (661) are rotatably connected to the inner wall of the sleeve (662); the outer wall of the sleeve (662) is fixedly connected to one end of the second tension spring (663); and the other end of the second tension spring (663) is hingedly connected to the fixed seat (664).

7. A radiation therapy field adjustment device as claimed in claim 6, characterized in that: The fixed seat (664) is provided with a through slot (665), and limiting slots (667) are provided on both sides of the through slot (665). The inner walls of the limiting slots (667) are slidably connected to limiting blocks (668), and both ends of the rotating shaft (65) are rotatably connected to the limiting blocks (668). The limiting blocks (668) are fixedly connected to the movable block (666), and the smooth section on the screw rod (332) is rotatably connected and passes through the movable block (666).

8. A radiation therapy field adjustment device as claimed in claim 3, characterized in that: The bottom of the arc-shaped guide rail (31) is fixedly connected to the mounting seat (312), the mounting seat (312) is fixedly connected to the bottom plate (1), and the reinforcing rod (313) is fixedly connected between two corresponding arc-shaped guide rails (31).

9. A radiation therapy field adjustment device as claimed in claim 8, characterized in that: One end of the driving shaft (61) is fixedly connected to the motor (611), and the motor (611) is fixedly connected to the bottom plate (1) via a motor base (612).

10. A radiation therapy field adjustment device as claimed in claim 9, characterized in that: The other end of the driving shaft (61) is connected to one end of a connecting rod (615) via a universal joint (614), and the other end of the connecting rod (615) is connected to the driving shaft (61) on the second adjustment component (4) via another universal joint (614).

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