Blade driving structure of multi-blade collimator

Abstract

The utility model belongs to the technical field of multi-blade collimators, and particularly relates to a blade driving structure of a multi-blade collimator, which comprises a constant-torque fixed-rotating-speed motor, a plurality of transmission subsystems and a plurality of blades, and the plurality of transmission subsystems are in one-to-one correspondence with the plurality of blades of the collimator; a single constant-torque fixed-rotating-speed motor is used as a power source, power is transmitted to collimator blades through transmission subsystems in one-to-one correspondence with a plurality of blades of the collimator, and the collimator blades are driven to complete linear motion; the power input ends of the transmission subsystems are connected in parallel. The driving blades only need a single high-power motor and are greatly different from a traditional multi-blade collimator, and the number of the blades of the traditional multi-blade collimator is the same as that of the motors for driving the blades. According to the driving structure, the moment of motion of the blades can be increased in a larger range, the motion speed is higher, the requirement for the size of the motor is greatly lowered, the requirement for the performance of the motor is lowered, and a large power change range is not needed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of multi-leaf collimator blade drive structure, belong to multi-leaf collimator technical field. BACKGROUND

[0002] Multi-leaf collimator design includes two symmetrically distributed blade boxes, a certain number of blades are configured in each box body, and the common configuration is 40 to 80 pieces per box, so the overall number of blades ranges between 80 to 160 pieces. The existing multi-leaf collimator mostly adopts a leaf independent driving mode, i.e. one motor drives one leaf of the multi-leaf collimator, so a large number of motors are required for each set of multi-leaf collimator, and the weight of the leaf is large, requiring high speed and precision. Limited by the size of the multi-leaf collimator, the smaller the size of the motor is, the better (which is conducive to expanding the number of leaves), and the larger the power is, the better (which is conducive to driving the leaf movement).

[0003] The technical scheme of the existing patent

a driving system

[0004] In response to the shortcomings of the prior art, the present invention aims to provide a multi-leaf collimator blade drive structure that addresses the shortcomings of existing multi-leaf collimators, which require numerous motors and require highly accurate motor encoders. By connecting a high-power motor to a drive shaft, which is then connected in parallel to multiple drive assemblies, the number of blades can be easily expanded. A small variable speed mechanism at the end of the drive assembly allows for precise adjustment of the speed of individual blades and the provision of varying torque to each blade.

[0005] The utility model provides a multi-leaf collimator blade driving structure, comprising:

[0006] A constant torque and constant speed motor, a plurality of transmission subsystems, and a plurality of blades, wherein the plurality of transmission subsystems correspond one to one with the plurality of blades of the collimator;

[0007] A constant torque and constant speed motor is connected to the drive shaft;

[0008] The transmission subsystem includes a permanent gear fixed on the drive shaft, the permanent gear is concentric with the drive shaft, and a plurality of permanent gears are arranged in parallel along the length direction of the drive shaft;

[0009] It also includes a shaft sleeve and a belt coupler sleeved on the support shaft, the support shaft is parallel to the drive shaft, the support shaft is fixed, the shaft sleeve and the belt coupler are fixedly connected, and the shaft sleeve can rotate on the support shaft but cannot move along the support shaft;

[0010] It also includes a driven gear sleeved on the shaft sleeve, which can move along the shaft sleeve but cannot rotate relative to the shaft sleeve; the driven gear is equipped with a pushing device that can make it move along the shaft sleeve.

[0011] It also includes a transmission, the input end of the transmission is connected to the belt coupler through a transmission belt, and the output end of the transmission is provided with a drive wheel, the teeth on the drive wheel are engaged with the blade coupling teeth, and the blade is driven to move linearly through the rotation of the drive wheel.

[0012] The transmission is a transmission cone, which comprises a cone A and a cone B, the cone A and the cone B each comprise a small end face and a large end face, a plurality of wires are connected between the small end face and the large end face, the wires are along the cone generatrix direction, and the plurality of wires are distributed in a circular array shape outside the cone.

[0013] When the blades are static, the intersection degree of the cone A and the cone B is the largest (the distance between the two is the shortest), which can provide the maximum torque and provide a larger starting acceleration for the blades.

[0014] The thickness of the driving wheel is smaller than the width of the blades, so that the driving wheel can be engaged with the coupling teeth of the blades regardless of the movement of the driving wheel.

[0015] The driven gear in the utility model adopts permanent magnet material, the pushing device is a strong magnetic coil, the strong magnetic coil is located on one side of the driven gear, and the brake disc fixed on the support shaft is arranged between the strong magnetic coil and the driven gear. When the strong magnetic coil is electrified, the driven gear moves a certain distance along the driving shaft, so as to be engaged with the always-moving gear and transmit power. The brake function: the strong magnetic coil is attached to the brake disc in the non-electric state, and remains in the static state, so that the blade driving structure can brake the blades. In the case of power failure or no signal of the equipment, the driven gear is attached to the brake disc, so that the blades will not move unexpectedly.

[0016] The single constant torque fixed speed motor is used as a power source, power is transmitted to collimator blades through a transmission subsystem corresponding to each blade of the collimator, and the collimator blades are driven to complete linear motion; the power input ends of the plurality of transmission subsystems are connected in parallel. The plurality of transmission subsystems of the driving mode are in parallel, each transmission subsystem is relatively independent, there is no energy transmission, and there is no energy attenuation. The constant torque fixed speed high-power motor is used to ensure the driving force of the blade movement, and there is no power shortage problem. The power input end of the transmission subsystem is a constant gear fixed on the driving shaft, the constant gear is concentric with the driving shaft, the plurality of constant gears are connected in parallel along the length direction of the driving shaft, and the driving shaft is connected with the constant torque fixed speed motor. In addition, the torque and speed of the power output end of the plurality of transmission subsystems are adjustable.

[0017] Compared with the prior art, the utility model has the beneficial effects that:

[0018] The multi-leaf collimator blade driving method and driving structure only need a single high-power motor, which is quite different from the traditional multi-leaf collimator, and the number of blades of the traditional multi-leaf collimator is the same as the number of motors for driving the blades. The driving structure of the patent can greatly improve the torque of the blade movement, and the movement speed is faster, the size requirement of the motor is greatly reduced, the performance requirement of the motor is reduced, and a large power variation range is not needed.

[0019] Reduce the number of motors and improve efficiency: by using a single constant torque fixed speed motor as a power source and connecting multiple transmission subsystems in parallel, the number of required motors is effectively reduced, and the complexity and cost of the system are reduced. At the same time, since each transmission subsystem is relatively independent, there is no energy transmission and attenuation problem, so the power can be more efficiently transmitted to each blade, and the power attenuation of the existing patent primary transmission gear set does not occur.

[0020] Enhance driving force and flexibility: using a high-power constant torque fixed speed motor ensures sufficient driving force for blade movement, avoiding the problem of insufficient power. In addition, by designing a small speed change structure (speed change cone cylinder) at the end of the transmission subsystem, the speed of a single blade can be accurately adjusted and different torques can be provided to meet different movement needs.

[0021] Optimize start-up and motion performance: the design of the speed change cone cylinder allows the blade to obtain a large start-up acceleration when stationary, and provides a higher speed when moving, thereby optimizing the start-up and motion performance of the blade. This design not only improves the motion efficiency of the blade, but also reduces energy loss.

[0022] Improve safety and reliability: the driven gear adopts permanent magnet material, cooperates with strong magnetic coil and brake disc design, realizes accurate control and brake of the blade, in the case of power failure or no signal of the equipment, the driven gear will be attached to the brake disc, ensures that the blade will not appear unexpected movement, improves the safety and reliability of the system.

[0023] Easy to expand and maintain: the driving structure and driving method of the utility model make the number of blades can be easily expanded, adapt to the demand of different scale of multi-leaf collimator. BRIEF DESCRIPTION OF DRAWINGS

[0024] Fig. 1 It is a leaf distribution structure schematic diagram of multi-leaf collimator;

[0025] Fig. 2 It is one of the transmission principle schematic diagram of the utility model;

[0026] Fig. 3 It is the second transmission principle schematic diagram of the utility model;

[0027] Fig. 4 It is the belt transmission schematic diagram in the utility model;

[0028] Fig. 5 It is the cross section schematic diagram of transmission belt;

[0029] Fig. 6 It is the overall structure schematic diagram of variable speed cone cylinder;

[0030] Fig. 7 It is the frame structure schematic diagram of variable speed cone cylinder one;

[0031] Fig. 8 It is the frame structure schematic diagram of variable speed cone cylinder two;

[0032] Fig. 9 It is the frame structure schematic diagram of variable speed cone cylinder three;

[0033] Fig. 10 It is the side view of cone A;

[0034] Fig. 11 It is the cooperation relationship schematic diagram of blade and driving wheel.

[0035] In the drawing: 1, blade;2, driving shaft;3, always moving gear;4, support shaft;5, driven gear;6, strong magnetic coil;7, brake disc;8, shaft sleeve;9, belt coupler;10, transmission belt;11, variable speed cone cylinder;12, driving wheel;13, tensioner;14, cone A;15, cone B;16, support;17, miniature bidirectional air cylinder;18, support column;19, small end face;20, large end face;21, sleeve;22, slot;23, wire;24, blade coupling tooth;25, guide wheel;26, limit block. DETAILED DESCRIPTION

[0036] The utility model will be further explained in connection with specific embodiments.

[0037] However, the description of the utility model is only an embodiment of structural and functional description, and the scope of the utility model is not limited by the embodiment described in the text.

[0038] For example, multiple embodiments can have multiple changes, multiple forms, and it should be understood that the scope of the utility model includes equivalents that can achieve the technical idea.

[0039] As shown in the figure, the multi-leaf collimator blade driving structure comprises: Figs. 1-11

[0040] The constant torque fixed speed motor is connected with a driving shaft 2; the transmission subsystem comprises a movable gear 3 fixed on the driving shaft 2, the movable gear 3 is concentric with the driving shaft 2, and a plurality of movable gears 3 are arranged in parallel along the length direction of the driving shaft 2;

[0041] The constant torque fixed speed motor is connected with a driving shaft 2; the transmission subsystem comprises a movable gear 3 fixed on the driving shaft 2, the movable gear 3 is concentric with the driving shaft 2, and a plurality of movable gears 3 are arranged in parallel along the length direction of the driving shaft 2;

[0042] It also includes a shaft sleeve 8 and a belt coupler 9 sleeved on the support shaft 4, the support shaft 4 is parallel to the driving shaft 2, the support shaft 4 is fixed, the shaft sleeve 8 and the belt coupler 9 are fixedly connected, the shaft sleeve 8 can rotate on the support shaft 4 but cannot move along the support shaft 4;

[0043] It also includes a driven gear 5 sleeved on the shaft sleeve 8, the driven gear 5 can move along the shaft sleeve 8 but cannot rotate relative to the shaft sleeve 8; the driven gear 5 is provided with a pushing device that can move it along the shaft sleeve 8. The pushing device is a strong magnetic coil 6, the driven gear 5 is made of permanent magnetic material, the strong magnetic coil 6 is located on one side of the driven gear 5, and the strong magnetic coil 6 and the driven gear 5 are provided with a brake disc 7 fixed on the support shaft 4.

[0044] ​The transmission is connected with the belt coupling 9 through the transmission belt 10, the output end of the transmission is provided with the driving wheel 12, the teeth on the driving wheel 12 are engaged with the blade coupling teeth 24, and the straight line movement of the blade 1 is driven through the rotation of the driving wheel 12. The transmission is a variable speed cone 11, the variable speed cone 11 comprises a cone A 14 and a cone B 15, the cone A 14 and the cone B 15 each comprise a small end face 19 and a large end face 20, a plurality of wires 23 are connected between the small end face 19 and the large end face 20, the wires 23 are along the cone generatrix direction, and the plurality of wires 23 are distributed in a circular array shape outside the cone. The small end face 19 of the cone A 14 and the cone B 15 is composed of a plurality of support rods distributed in a radial manner, the two end faces of the cone A 14 are connected through the central support column 18, the two end faces of the cone B 15 are connected through the central sleeve 21, a plurality of insertion slots 22 are arranged on the wall of the sleeve 21, the insertion slots 22 are strip-shaped and are along the length direction of the sleeve 21, the insertion slots 22 correspond to the plurality of support rods that compose the small end face 19 one by one, the small end faces of the cone A 14 and the cone B 15 are cross-connected, and the cross depth is adjustable. The transmission belt 10 is connected on the cross contact surface of the cone A 14 and the cone B 15. The variable speed cone 11 is rotatably arranged between a pair of supports 16 at both ends, and a micro bidirectional air cylinder 17 is further arranged between the pair of supports 16. The micro bidirectional air cylinder 17 can adjust the cross depth of the cone A 14 and the cone B 15. The thickness of the driving wheel 12 is less than the width of the blade 1.

[0045] The utility model discloses a single constant torque fixed speed motor is used as power source, through the drive subsystem that corresponds to the several blades of collimator, power transmission is given to collimator blade, drives collimator blade to complete linear motion, the power input end of several drive subsystems is parallel connection: the power input end of drive subsystem is the always -moving gear 3 of fixing on the drive shaft 2, always -moving gear 3 is concentric with drive shaft 2, and several always -moving gears 3 are arranged in parallel along the length direction of drive shaft 2. The torque and rotational speed of the power output end of several drive subsystems are adjustable. The power source of drive structure comes from drive shaft, and drive shaft is connected with a constant torque fixed speed high -power motor (a multi -leaf collimator has two blade boxes, and two high -power motors, and one is in each box). Motor connects drive shaft 2, and 60 always -moving gears 3 are installed on each drive shaft 2, and always -moving gear 3 can be engaged with driven gear 5. Driven gear 5 can drive belt coupling 9 (equivalent to pulley), and power is transmitted to transmission (variable speed cone 11) through transmission belt 10. Variable speed cone 11 connects driving wheel 12, and driving wheel 12 is engaged with blade coupling teeth 24. 4) always -moving gear is installed on drive shaft, and drive shaft is connected with high -power motor.

[0046] The principle of the variable speed cone combination structure: cone A14 and cone B15 are cross-connected, and cone A14 and cone B15 are hollow cone structures without sharp structures. The support column 18 (or sleeve 21) connects the small end face 19 and the large end face 20, and the outer edges of the small end face 19 and the large end face 20 are uniformly distributed with a plurality of small holes. High-strength wire 23 passes through the adjacent small holes of the two end faces (not shown in the figure) and is woven into the outer shell of a single cone. The outer dimensions of cone A14 and cone B15 are the same, and cone A14 and cone B15 are nested structures. Cone A14 and cone B15 are connected by support column 18 and sleeve 21, and support column 18 is inserted into sleeve 21. The wires 23 on the outer surfaces of cone A14 and cone B15 are staggered. The miniature bidirectional air cylinder 17 can push the variable speed cone 11 to move from both sides. When the cross distance between cone A14 and cone B15 becomes larger, the diameter of the contact surface of the two cones becomes larger, the transmission torque of the driving wheel 12 connected thereto becomes larger, and the blade speed decreases. When the cross distance between cone A14 and cone B15 becomes smaller, the diameter of the contact surface of the two cones becomes smaller, the transmission torque of the driving wheel 12 connected thereto becomes smaller, and the blade speed increases.

[0047] The contact surface of the two variable speed cones is installed with a transmission belt 10, and the cross-sectional lower end face angle of the transmission belt 10 is the same as the angle of the contact surface of the two cones, and the transmission belt 10 is in close contact with the transmission belt 10. The other end of the transmission belt 10 is connected with the belt coupler 9, and the contact surface of the belt coupler 9 and the transmission belt 10 is the same as the shape of the lower end face of the transmission belt 10, and the transmission belt 10 is in close contact with the transmission belt 10. The transmission belt 10 is provided with a tensioner 13, and the tensioner 13 has a certain tension, which always stretches the transmission belt 10 outward, so that the transmission belt 10 is always in a tension state.

[0048] The driven gear 5 is made of high-strength permanent magnetic material, and the strong magnetic coil 6 drives the driven gear 5 to move a certain distance along the shaft sleeve 8 when energized, so as to mesh with the movable gear 3 and transmit power. The strong magnetic coil 6 is in close contact with the brake disc 7 in the non-energized state, and remains in the static state, and the blade driving structure has a braking effect on the blade 1. In the case of power failure or no signal of the equipment, the driven gear 5 is in close contact with the brake disc 7, so as to ensure that the blade 1 will not move unexpectedly. The miniature bidirectional air cylinder 17 controlling the variable speed cone 11 is linked with the strong magnetic coil 6 under the control of the control system. When the strong magnetic coil 6 is energized, the miniature bidirectional air cylinder 17 extends, the diameter of the contact surface of the two cones gradually becomes smaller, and the speed of the blade 1 gradually increases; when the strong magnetic coil 6 is de-energized, the miniature bidirectional air cylinder 17 retracts, the diameter of the contact surface of the two cones gradually becomes larger, and waits for the next start. The blade can obtain a larger starting acceleration when it is static, and can provide a higher rotating speed when it is moving, so as to optimize the starting and moving performance of the blade.

[0049] Of course, the above only the preferred embodiments of the present application, can not be considered to limit the scope of the embodiments of the present application. The present application is not limited to the above examples, the ordinary skilled in the art within the scope of the present application made by the equivalent changes and improvements, should be attributed to the present application within the scope of the patent.

Claims

1. A multi-leaf collimator leaf drive structure, characterized by, The utility model relates to a constant torque fixed speed motor, a plurality of transmission subsystems, a plurality of blades (1), a plurality of transmission subsystems correspond to the plurality of blades (1) of collimator one to one. The constant torque fixed speed motor is connected with a driving shaft (2). The transmission subsystem comprises a movable gear (3) fixed on the driving shaft (2), the movable gear (3) is concentric with the driving shaft (2), and a plurality of movable gears (3) are arranged in parallel along the length direction of the driving shaft (2). The utility model further comprises a shaft sleeve (8) and a belt coupler (9) sleeved on a support shaft (4), the support shaft (4) is parallel with the driving shaft (2), the support shaft (4) is fixed, the shaft sleeve (8) and the belt coupler (9) are fixedly connected, the shaft sleeve (8) can rotate on the support shaft (4) but cannot move along the support shaft (4). The utility model further comprises a driven gear (5) sleeved on the shaft sleeve (8), the driven gear (5) can move along the shaft sleeve (8) but cannot rotate relative to the shaft sleeve (8); the driven gear (5) is provided with a pushing device for moving along the shaft sleeve (8), the driven gear (5) is made of permanent magnetic material, and the pushing device is a strong magnetic coil (6); the strong magnetic coil (6) is located on one side of the driven gear (5), and a brake disc (7) fixed on the support shaft (4) is arranged between the strong magnetic coil (6) and the driven gear (5). The utility model further comprises a transmission, the input end of the transmission is connected with the belt coupler (9) through a transmission belt (10), the output end of the transmission is provided with a driving wheel (12), the teeth on the driving wheel (12) are engaged with blade coupling teeth (24), and the driving wheel (12) drives the linear motion of the blade (1) through rotation. The transmission is a variable speed cone cylinder (11), the variable speed cone cylinder (11) comprises a cone A (14) and a cone B (15), the cone A (14) and the cone B (15) each comprise a small end face (19) and a large end face (20), a plurality of wires (23) are connected between the small end face (19) and the large end face (20), the wires (23) are each along the cone generatrix direction, and the plurality of wires (23) are distributed in a circular array shape outside the cone; the small end face (19) of the cone A (14) and the cone B (15) each is composed of a plurality of support rods distributed in a radial manner, the two end faces of the cone A (14) are connected through a central support column (18), the two end faces of the cone B (15) are connected through a sleeve (21) in the center, a plurality of insertion slots (22) are arranged on the sleeve (21) wall, the insertion slots (22) are strip-shaped along the length direction of the sleeve (21), the insertion slots (22) correspond to the plurality of support rods composing the small end face (19) one to one, the small end faces of the cone A (14) and the cone B (15) are cross-connected, and the cross depth is adjustable; the transmission belt (10) is connected on the cross contact surface of the cone A (14) and the cone B (15).

2. The multi-leaf collimator leaf drive structure of claim 1, wherein, The two ends of the variable speed cone cylinder (11) are rotatably arranged between a pair of supports (16), and a micro bidirectional air cylinder (17) is further arranged between the pair of supports (16), and the micro bidirectional air cylinder (17) can adjust the cross depth of the cone A (14) and the cone B (15).

3. The multi-leaf collimator leaf drive structure of claim 2, wherein, The thickness of the driving wheel (12) is less than the width of the blade (1).

4. The multi-leaf collimator leaf drive structure of claim 2, wherein, ​

Images