# US 11,439,845 B2 · Multi-leaf collimator > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,439,845 B2 - Document ID: US11439845B2 - Status: Granted - Kind: B2 - Application number: 16/417,750 - Filed: 2019-05-21 - Published: 2020-01-23 - Granted: 2022-09-13 - Earliest claimed: 2018-07-23 - Assignees: Shanghai United Imaging Healthcare Co., Ltd. - Applicants: Shanghai United Imaging Healthcare Co., Ltd. - Inventors: Jian Zhang; Kun Yang; Xiao Fang - Web page: https://patentgrep.com/patent/US11439845B2 ## CPC - A61N 5/1045: {using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT} - A61N 5/1036: {Leaf sequencing algorithms} - A61N 5/1065: {Beam adjustment} - A61N 2005/1074: {Details of the control system, e.g. user interfaces} - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) ## Abstract The present disclosure relates a multi-leaf collimator. The multi-leaf collimator may include a plurality of leaf modules. Each leaf module of the plurality of leaf modules may include a leaf configured to shield a portion of beams emitted by a radiation source. The leaf may be movable along a guide rail of the multi-leaf collimator. Each leaf module may also include a drive mechanism including a first drive component and a second drive component. The first drive component and the second drive component may be both connected to the leaf. The first drive component and the second drive component may jointly actuate the leaf to move along the guide rail. ## Claims ### Claim 1 A multi-leaf collimator, comprising: a plurality of leaf modules; wherein each leaf module of the plurality of leaf modules includes: a leaf configured to shield a portion of beams emitted by a radiation source, the leaf being movable along a guide rail of the multi-leaf collimator; and a drive mechanism including a first drive component and a second drive component, the first drive component and the second drive component being both connected to the leaf, wherein the first drive component and the second drive component jointly actuate the leaf to move along the guide rail. ### Claim 2 (depends on 1) The multi-leaf collimator of claim 1, wherein the second drive component includes: an air cylinder configured to accommodate compressed gas; a piston configured to output a driving force to the leaf when driven by the compressed gas, the piston being connected to the air cylinder; and a first position encoder connected to the piston, the first position encoder being capable of moving with the piston to detect a position of the leaf. ### Claim 3 (depends on 2) The multi-leaf collimator of claim 2, further comprising: a transmission shaft configured to transmit the driving force to the leaf, wherein a first end of the transmission shaft is connected to the piston, and a second end of the transmission shaft is connected to the leaf. ### Claim 4 (depends on 3) The multi-leaf collimator of claim 3, wherein the transmission shaft is flexible and is configured to arrange the air cylinder flexibly, and each leaf module of the plurality of leaf modules further includes: a shaft sleeve configured to accommodate the flexible transmission shaft. ### Claim 5 (depends on 1) The multi-leaf collimator of claim 1, wherein the first drive component includes a speed increaser configured to increase a revolution speed of the first drive component. ### Claim 6 (depends on 1) The multi-leaf collimator of claim 1, further comprising: a transmission component coupled to the first drive component, the transmission component being configured to transmit a driving force to the leaf. ### Claim 7 (depends on 6) The multi-leaf collimator of claim 6, wherein the transmission component includes: a lead screw connected to the first drive component and rotatable with a rotation of a motor of the first drive component; and a nut fixed to the leaf, wherein the lead screw further includes a plurality of external threads, the nut further includes a plurality of internal threads, and the plurality of internal threads of the nut are engageable with the external threads of the lead screw for actuating the leaf to move when the lead screw rotates. ### Claim 8 (depends on 1) The multi-leaf collimator of claim 1, wherein the first drive component and the second drive component simultaneously actuate the leaf to move along the guide rail, wherein the first drive component and the second drive component actuate the leaf to move with a same speed. ### Claim 9 (depends on 1) The multi-leaf collimator of claim 1, wherein the first drive component and the second drive component non-simultaneously actuate the leaf to move along the guide rail. ### Claim 10 (depends on 9) The multi-leaf collimator of claim 9, wherein the second drive component firstly actuates the leaf to move to a first position at a first speed, and the first drive component actuates the leaf to move from the first position to a target position at a second speed, the second speed being lower than the first speed. ### Claim 11 (depends on 10) The multi-leaf collimator of claim 10, further comprising: a transmission component including a modified lead screw and a modified nut, wherein the modified lead screw is connected to the first drive component, and the modified nut is fixed to the leaf. ### Claim 12 (depends on 11) The multi-leaf collimator of claim 11, wherein at least a portion of an outer circumference of the modified lead screw includes external threads. ### Claim 13 (depends on 11) The multi-leaf collimator of claim 11, wherein the modified lead screw includes a first surface and a second surface, and a portion of the modified nut includes a gap, wherein a thickness of the modified lead screw between the first surface and the second surface is less than a width of the gap of the portion of the modified unit. ### Claim 14 (depends on 13) The multi-leaf collimator of claim 13, wherein the modified lead screw is not engageable with the modified nut when the second drive component actuates the leaf to move, or the modified lead screw is engageable with the modified nut when the first drive component actuates the leaf to move. ### Claim 15 A system for controlling a multi-leaf collimator, comprising: at least one storage device including a set of instructions for controlling a movement of the multi-leaf collimator; at least one processor in communication with the at least one storage device, wherein when executing the set of instructions, the at least one processor is configured to cause the system to: determine a target position that a leaf of the multi-leaf collimator needs to reach; and actuate, by a first drive component and a second drive component, the leaf to move to the target position, wherein the first drive component and the second drive component are both connected to the leaf, and each drive component independently actuates the leaf. ### Claim 16 (depends on 15) The system of claim 15, wherein to actuate the leaf to move to the target position, the at least one processor is further configured to cause the system to: actuate the leaf to move to the target position by the first drive component and the second drive component simultaneously. ### Claim 17 (depends on 15) The system of claim 15, wherein to actuate the leaf to move to the target position, the at least one processor is further configured to cause the system to: actuate, by the second drive component, the leaf to move to a first position at a first speed; and actuate, by the first drive component, the leaf to move from the first position to the target position at a second speed, the second speed being lower than the first speed. ### Claim 18 (depends on 15) The system of claim 15, wherein the multi-leaf collimator includes a transmission component including a modified lead screw and a modified nut, wherein the modified lead screw is connected to the first drive component, and the modified nut is fixed to the leaf. ### Claim 19 (depends on 18) The system of claim 18, wherein the at least one processor is further configured to cause the system to: determine whether the modified lead screw is engaging with the modified nut; in response to a determination that the modified lead screw is not engageable with the modified nut, actuate the leaf to move to a first position by the second drive component; and actuate the leaf to move from the first position to the target position by the first drive component. ### Claim 20 (depends on 19) The system of claim 19, wherein the at least one processor is further configured to cause the system to: in response to a determination that the modified lead screw is engageable with the modified nut, adjust the modified lead screw such that the modified lead screw is not engageable with the modified nut; actuate the leaf to move to the first position by the second drive component; and actuate the leaf to move from the first position to the target position by the first drive component. ### Claim 21 A method implemented on a computing device having at least storage device and at least one processor, comprising: determining a target position that a leaf of a multi-leaf collimator needs to reach; and actuating, by a first drive component and a second drive component, the leaf to move to the target position, wherein the first drive component and the second drive component are both connected to the leaf, and each drive component independently actuates the leaf.