A grating assembly and radiotherapy apparatus

Abstract

This application provides a grating assembly and a radiotherapy device. The grating assembly includes: a frame, grating blades, and at least two sensors. The grating blades are slidably disposed on the frame and can slide back and forth along a first direction. The top of the grating blades has at least two types of positioning parts alternately arranged along the first direction. The at least two sensors are spaced apart on the frame along the first direction. When the grating blades move to different positioning parts and are opposite to the sensors, the sensors emit different signals. At the same time, the signals from at least two sensors form a composite signal, and the composite signal has at least three types. The above-mentioned grating assembly can directly obtain the actual position of the grating blades, effectively reducing the impact of transmission system clearance, installation error, and processing error of the grating blades on the accuracy of grating blade position detection, thereby achieving the goal of improving the accuracy of grating blade position detection.

Description

Technical Field

[0001] This application relates to the field of radiotherapy equipment, and more particularly to a grating assembly and a radiotherapy device. Background Technology

[0002] Radiotherapy is now widely used for tumor treatment. The multi-leaf collimator (MLC) is a core component of radiotherapy equipment, and its performance directly affects the overall performance of the device. The MLC can adjust the collimator blades according to the shape of the patient's tumor to create an irregular radiation field, thus avoiding damage to healthy tissues.

[0003] In related technologies, the movement of MLC grating blades is achieved through a DC motor driven by an encoder and a lead screw transmission. Although the position of the blades can be calculated by the encoder of the DC motor, due to the existence of lead screw backlash, transmission system installation errors, and manufacturing errors, there will be an error between the grating blade position obtained by the motor encoder based on the motor speed and the actual movement position of the grating blades, which will lead to a decrease in the accuracy of grating blade position detection. Summary of the Invention

[0004] In view of this, this application provides a grating assembly and a radiotherapy device to improve the accuracy of grating leaf position detection.

[0005] Specifically, this application is implemented through the following technical solution: In a first aspect, this application provides a grating assembly, comprising: a frame, grating blades, and at least two sensors; wherein... The grating blade is slidably disposed on the frame and can slide back and forth along the first direction; the top end of the grating blade has at least two types of positioning parts alternately arranged along the first direction; at least two of the sensors are spaced apart on the frame along the first direction. When the grating blades move to different positioning positions and are opposite the sensor, the sensor emits different signals; At the same time, the signals from at least two of the sensors form a composite signal, and the composite signal has at least three types.

[0006] In the aforementioned grating assembly, the positioning unit also moves relative to the sensor as the grating blades move, enabling the sensor to emit different composite signals. By recording these composite signals, a composite signal sequence can be obtained. The order of the composite signals within this sequence reveals the direction of movement of the grating blades. Combining this with the width of the positioning unit and the counting of the composite signals, the distance traveled by the grating blades can be calculated, thus allowing the detection of the grating blades' position. This method directly obtains the actual position of the grating blades, effectively reducing the impact of transmission system clearances, installation errors, and manufacturing errors on the accuracy of grating blade position detection, thereby improving the accuracy of grating blade position detection.

[0007] In one possible implementation, at least two of the sensors include a first sensor and a second sensor, and at least two of the positioning units include a first positioning unit and a second positioning unit.

[0008] In one possible implementation, the width of the first positioning part in the first direction is L1, the width of the second positioning part in the first direction is L2, and the distance between the first sensor and the second sensor is L3, wherein L1, L2, and L3 satisfy: L3 is not a positive integer multiple of (L1 + L2).

[0009] In one possible implementation, L1, L2, and L3 also satisfy: L1 = L2, and L3 = (n + 0.5)L1, where n is an integer not less than 0.

[0010] In one possible implementation, L1, L2, and L3 also satisfy: L3 = 1.5L1.

[0011] In one possible implementation, the top end of the grating blade is provided with grooves of equal width that are evenly spaced along a first direction, each groove being a first positioning part, and the protrusion between two adjacent grooves being a second positioning part. The first sensor and the second sensor are distance sensors.

[0012] In one possible implementation, the frame is provided with a fixing sleeve in which the first sensor and / or the second sensor are detachably fixed.

[0013] In one possible implementation, the grating assembly further includes a support plate fixed to the frame and disposed opposite to the top tip of the grating blades; The first sensor includes a first signal transmitter and a first signal receiver fixed on the carrier plate, and the first signal transmitter and the first signal receiver are arranged at intervals relative to each other along the thickness direction of the grating blade; The second sensor includes a second signal transmitter and a second signal receiver fixed on the carrier plate, the second signal transmitter and the second signal receiver being arranged at intervals relative to each other along the thickness direction of the grating blade; The grating assembly further includes a baffle, the baffle having blocking portions spaced apart along a first direction; the blocking portions serve as first positioning portions, and the interval region between adjacent blocking portions serves as second positioning portions; as the grating blades move, the blocking portions intermittently block between the first signal receiver and the first signal transmitter, and intermittently block between the second signal receiver and the second signal transmitter, so that the first sensor and the second sensor alternately emit two signals.

[0014] In one possible implementation, in the direction in which the grating blades point toward the carrier plate, there is a gap between the first signal transmitter and the carrier plate, and the edge of the shielding portion near the carrier plate is located within the gap between the first signal transmitter and the carrier plate; In the direction in which the grating blades point toward the carrier plate, there is a gap between the second signal transmitter and the carrier plate, and the edge of the shielding portion near the carrier plate is located within the gap between the second signal transmitter and the carrier plate.

[0015] In one possible implementation, the carrier plate is a circuit board; A capacitor is provided between the first signal transmitter and the circuit board, and / or a capacitor is provided between the first signal receiver and the circuit board; A capacitor is provided between the second signal transmitter and the circuit board, and / or a capacitor is provided between the second signal receiver and the circuit board.

[0016] In one possible implementation, the baffle further includes a connecting strip, and the plurality of the blocking portions are fixedly connected to the connecting strip; The connecting strip is fixedly connected to the grating blade.

[0017] In one possible implementation, the number of grating blades is at least two, and the at least two grating blades are spaced apart along the thickness direction of the grating blades; The sensors corresponding to two adjacent grating blades are staggered in the thickness direction of the grating blades.

[0018] In one possible implementation, when the first sensor includes a first signal transmitter and a first signal receiver, and the second sensor includes a second signal transmitter and a second signal receiver, the sensors corresponding to two adjacent grating blades satisfy the following: The first signal transmitter, first signal receiver, second signal transmitter, and second signal receiver of all the aforementioned sensors are arranged in three columns along the first direction.

[0019] Secondly, this application provides a radiotherapy device, including any of the grating components described above.

[0020] In the aforementioned radiotherapy equipment, the grating assembly's positioning unit moves relative to the sensor as the grating blades move. This allows the sensor to emit different composite signals. By recording these composite signals, a composite signal sequence can be obtained. The order of the composite signals within this sequence reveals the direction of the grating blades' movement. Combining this with the width of the positioning unit and counting the composite signals, the distance the grating blades have traveled can be determined, thus enabling the detection of the grating blades' position. This method directly obtains the actual position of the grating blades, effectively reducing the impact of transmission system clearances, installation errors, and manufacturing errors on the accuracy of grating blade position detection, thereby improving the accuracy of grating blade position detection.

[0021] In one possible implementation, the radiotherapy device further includes a controller for determining the position of the grating blades based on a composite signal sequence during the movement of the grating blades. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall grating assembly in an embodiment of this application; Figure 2 This is a schematic diagram of the grating blades in an embodiment of this application; Figure 3 This is one of the schematic diagrams illustrating the grating blade position detection principle in the embodiments of this application; Figure 4 This is the second schematic diagram of the grating blade position detection principle in the embodiments of this application; Figure 5 This is a schematic diagram of a structure with a groove in an embodiment of this application; Figure 6 This is a schematic diagram of sensor fastening in an embodiment of this application; Figure 7 This is a schematic diagram showing the sensors being staggered along the thickness direction of the grating blades in an embodiment of this application; Figure 8 This is the second overall schematic diagram of the grating assembly in the embodiments of this application; Figure 9 This is a schematic diagram of the first signal transmitter and the first signal receiver in the embodiments of this application; Figure 10 This is a schematic diagram of the baffle in an embodiment of this application; Figure 11This is one of the schematic diagrams showing the arrangement of the signal transmitter and signal receiver in the embodiments of this application; Figure 12 This is the second schematic diagram showing the arrangement of the signal transmitter and signal receiver in the embodiments of this application.

[0023] In the diagram: 1. Frame, 11. Sleeve, 12. Threaded push rod, 2. Grating blade, 3. Sensor, 31. First sensor, 311. First signal transmitter, 312. First signal receiver, 32. Second sensor, 321. Second signal transmitter, 322. Second signal receiver, 4. Positioning part, 41. First positioning part, 42. Second positioning part, 5. Baffle, 51. Shielding part, 52. Connecting strip, 6. Bearing plate, 7. Capacitor. Detailed Implementation

[0024] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0025] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0026] It should be understood that although the terms first, second, third, etc., may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0027] Radiotherapy is now widely used for tumor treatment. The multi-leaf collimator (MLC) is a core component of radiotherapy equipment, and its performance directly affects the overall performance of the device. The MLC can adjust the collimator blades according to the shape of the patient's tumor to create an irregular radiation field, thus avoiding damage to healthy tissues.

[0028] In related technologies, the movement of MLC grating blades is achieved through a DC motor driven by an encoder and a lead screw transmission. Although the position of the blades can be calculated by the encoder of the DC motor, due to the existence of lead screw backlash, transmission system installation errors, and manufacturing errors, there will be an error between the grating blade position obtained by the motor encoder based on the motor speed and the actual movement position of the grating blades, which will lead to a decrease in the accuracy of grating blade position detection.

[0029] In view of this, this application provides a grating assembly and a radiotherapy device to improve the accuracy of grating leaf position detection. The grating assembly provided in this application will be described in detail below with reference to the accompanying drawings.

[0030] Please refer to the above. Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a schematic diagram of the overall grating assembly in an embodiment of this application. Figure 2 This is a schematic diagram of the grating blades in an embodiment of this application. Figure 3 This is one of the schematic diagrams illustrating the grating blade position detection principle in the embodiments of this application.

[0031] The grating assembly provided in this application includes a frame 1, grating blades 2, and at least two sensors 3. The frame 1 is used to support the grating blades 2 and the sensors 3, and the sensors 3 are configured in conjunction with the grating blades 2 to detect the position of the grating blades 2.

[0032] The grating blade 2 is slidably mounted on the frame 1 and can slide back and forth along a first direction. Specifically, a sliding track can be provided on the frame 1, and the grating blade 2 is slidably connected to the track and can slide relative to the track; the driving device for the grating blade 2 can be a motor, lead screw, etc., mounted on the frame 1. Driven by the driving device, the grating blade 2 can slide back and forth along the first direction and can stop at a set position in the first direction.

[0033] The top of the grating blade 2 has at least two types of positioning parts 4 arranged alternately along a first direction; at least two sensors 3 are spaced apart along the first direction in the frame 1; and when the grating blade 2 moves to different types of positioning parts 4 and is opposite to the sensors 3, the sensors 3 emit different signals.

[0034] Specifically, the top end of the grating blade 2 can refer to the end of the grating blade 2 that is perpendicular to the thickness direction of the grating blade 2 and perpendicular to the first direction. For example, the grating blade 2 has a thickness direction and a length direction and a width direction that are perpendicular to the thickness direction. For example, if the first direction is the length direction of the grating blade 2, then the top end of the grating blade 2 is one end in the width direction of the grating blade 2.

[0035] In the width direction of the grating blade 2, the sensor 3 can be spaced apart from the grating blade 2; or, in the width direction of the grating blade 2, the grating blade 2 can overlap with the sensor 3, and at this time, the grating blade 2 and the sensor 3 can maintain a certain distance in the thickness direction of the grating blade 2.

[0036] The positioning parts 4 are of at least two types, specifically two, three, four, or more. These positioning parts 4 are alternately arranged along the first direction, meaning that any two adjacent positioning parts 4 are of different types. For example, when the positioning parts 4 include two types, A and B, the two types of positioning parts 4 can be alternated in the pattern ABABAB…; as another example, when the positioning parts 4 include three types, ABC, the three types of positioning parts 4 can be alternated in the pattern ABCABCABC… It is worth noting that, in the specific arrangement of the positioning parts 4, the width of two adjacent positioning parts 4 along the first direction can be the same or different.

[0037] The number of sensors 3 can be two, three, four, or more. These sensors 3 can be of the same or different types, as long as the following condition is met: when the grating blade 2 moves along the first direction, causing each sensor 3 to alternately face different types of positioning parts 4, each sensor 3 can emit a signal corresponding to the type of positioning part 4 corresponding to that sensor 3. For example, the positioning parts 4 include two types, A and B. When a sensor 3 faces positioning part A, it emits signal 'a'; when it faces positioning part B, it emits signal 'b'. As the grating blade 2 slides along the first direction, the sensor 3 will continuously emit a sequence of signals: ababab...

[0038] Optionally, when specifically setting the positioning part 4, two adjacent positioning parts 4 are set close together; this setting can reduce the no-signal area between two adjacent positioning parts 4, so that the sensor 3 can continuously emit signals.

[0039] When the grating blade 2 moves to a certain position, at least two sensors 3 emit corresponding signals according to the type of positioning part 4 opposite to the sensor 3. At the same time, the signals of all sensors 3 constitute the composite signal at that moment. In the embodiments of this application, the positioning part 4 and the sensors 3 satisfy the following condition: during the movement of the grating blade 2, the composite signal emitted by at least two sensors 3 has at least three types. When the grating blade 2 moves forward and backward in the first direction, the arrangement order of the at least three composite signals is different. The composite signal satisfies this condition by adjusting the number of types of positioning parts 4, the arrangement of positioning parts 4, the distance between sensors 3, etc.

[0040] For example, when the composite signal includes three types (A, B, and C), by adjusting the number of types of positioning units 4, the arrangement of positioning units 4, and the distance of sensors 3, the composite signal sequence can be "A B C A B C..." when the grating blade 2 moves forward in the first direction, and "A C B A C B..." when the grating blade 2 moves backward in the first direction. Furthermore, given the dimensions and arrangement of the positioning units 4 and the distance of sensors 3, the distance the grating blade 2 has moved during a given period can be calculated by counting the number of composite signals within the composite signal sequence. In this exemplary example, when the grating blade 2 starts moving from the origin, the corresponding upper-level controller can read and analyze the composite signal sequence, determine the direction of movement of the grating blade 2 by the order of the composite signal sequence, and then calculate the position of the grating blade 2 in real time by counting the number of composite signals within the composite signal sequence.

[0041] Of course, the types of composite signals are not limited to three; there can also be four or more. When there are four or more types of composite signals, the method for monitoring the state of the grating blade 2 can still refer to the case where there are three types of composite signals, as described above, and will not be repeated here.

[0042] It is worth noting that, in the specific configuration of the positioning unit 4 and the sensor 3, the positioning unit 4 and the sensor 3 can be distinguished by means of changes in distance, magnetism, etc. For example, if the sensor 3 is a distance sensor, the distance between the sensor 3 and different areas at the end of the grating blade 2 can be changed to make the sensor 3 emit different signals when it is opposite to different areas; similarly, if the sensor 3 is a magnetic sensor, the magnetism of different areas at the end of the grating blade 2 can be changed to make the sensor 3 emit different signals when it is opposite to different areas.

[0043] In summary, the grating assembly provided in this application allows the positioning part 4 to move relative to the sensor 3 when the grating blade 2 moves. This enables the sensor 3 to emit different composite signals. By recording these composite signals, a composite signal sequence can be obtained. The direction of movement of the grating blade 2 can be determined by the arrangement of the composite signals within the sequence. Combined with the width of the positioning part 4 and the counting of the composite signals, the distance traveled by the grating blade 2 can be obtained, thereby detecting the position of the grating blade 2. This method directly obtains the actual position of the grating blade 2, effectively reducing the impact of transmission system clearance, installation errors, and processing errors on the accuracy of grating blade 2 position detection, thus achieving the goal of improving the accuracy of grating blade 2 position detection.

[0044] The grating assembly provided in this application embodiment can also be specifically used for high-resolution multi-leaf gratings. Specifically, some existing multi-leaf gratings have springs and brushes at the tail of the grating leaves, with the brushes resting against a varistor. By using the grating leaves to drive the brushes relative to the varistor, the varistor outputs different voltages, thereby determining the position of the grating leaves. However, for high-resolution multi-leaf gratings, as an example, the width of the leaves at the isocenter of mainstream high-resolution multi-leaf gratings is 2.5mm, meaning the width of the upper multi-leaf grating leaves is only 1.5mm. Setting springs and brushes on such narrow grating leaves, along with corresponding varistors, presents disadvantages such as high manufacturing difficulty and high failure rate of the varistors, easy wear and poor reliability of the brushes, and the need to replace the entire set of brushes and varistors during maintenance, resulting in high maintenance difficulty and cost. The solution provided in this application, which utilizes the cooperation of sensor 3 and positioning part 4, does not require contact between sensor 3 and positioning part 4, thus reducing the generation of losses and improving reliability. Furthermore, when repairing sensor 3 and positioning part 4, sensor 3 or positioning part 4 of a certain grating blade 2 can be repaired or replaced separately, thereby reducing the difficulty and cost of repair.

[0045] As an optional implementation, when specifically setting the sensor 3 and the positioning part 4, the sensor 3 includes a first sensor 31 and a second sensor 32, and the positioning part 4 includes a first positioning part 41 and a second positioning part 42. The first sensor 31 can emit two different signals when it is opposite to the first positioning part 41 and the second positioning part 42, and the second sensor 32 can also emit two different signals when it is opposite to the first positioning part 41 and the second positioning part 42. The two signals of the first sensor 31 and the two signals of the second sensor 32 can form up to four composite signals. By designing the width of the first positioning part 41 and the second positioning part 42 in the first direction and the spacing between the first sensor 31 and the second sensor 32 in the first direction, it is possible to achieve three or four types of composite signals, and the arrangement order of the composite signals in the composite signal sequence generated when the grating blade 2 moves forward or backward along the first direction is different.

[0046] It is worth noting that a plurality of first positioning portions 41 and a plurality of second positioning portions 42 are alternately arranged at the top of the grating blade 2; for the plurality of first positioning portions 41, the width of these first positioning portions 41 in the first direction can be the same or different; similarly, for the plurality of second positioning portions 42, the width of these second positioning portions 42 in the first direction can also be the same or different; the specific width of the first positioning portion 41 and the second positioning portion 42 should be determined according to the requirements for positioning the grating blade 2.

[0047] In this optional embodiment, the purpose of real-time monitoring of the position of the grating blade 2 can be achieved by using two positioning parts 4 and two sensors 3, which can reduce the process difficulty of setting up the positioning parts 4 and sensors 3.

[0048] As an optional implementation, when specifically setting the first positioning part 41, the second positioning part 42, the first sensor 31 and the second sensor 32, the width of the first positioning part 41 in the first direction is L1, the width of the second positioning part 42 in the first direction is L2, and the distance between the first sensor 31 and the second sensor 32 is L3. L1, L2 and L3 satisfy: L3 is not equal to a positive integer multiple of (L1 + L2).

[0049] In this optional embodiment, all the first positioning parts 41 have the same width, and all the second positioning parts 42 have the same width. This arrangement can further reduce the manufacturing process difficulty of the first positioning parts 41 and the second positioning parts 42.

[0050] All first positioning parts 41 have the same width, and all second positioning parts 42 have the same width. The first positioning parts 41 and second positioning parts 42 are alternately arranged. In this arrangement, one first positioning part 41 and an adjacent second positioning part 42 can be considered a combination, and all first positioning parts 41 and second positioning parts 42 can be considered as a series of such combinations. The width of each combination in the first direction is the sum of the widths of the first positioning parts 41 and 42 in the first direction. If the distance between the first sensor 31 and the second sensor 32 in the first direction is set to be an integer multiple of the sum of the widths of the first positioning parts 41 and 42 in the first direction, only two types of composite signals will be generated when the grating blade 2 moves. However, if the distance between the first sensor 31 and the second sensor 32 in the first direction is not an integer multiple of the sum of the widths of the first positioning parts 41 and 42 in the first direction, three or four types of composite signals will be generated when the grating blade 2 moves, which can meet the conditions required for detecting the position of the grating blade 2.

[0051] As an optional implementation, L1, L2, and L3 satisfy: L1 = L2, and L3 = (n + 0.5)L1, where n is an integer not less than 0. Specifically, n can be 0, 1, 2, 3, etc. In this optional implementation, there are four types of composite signals, which can meet the conditions required for detecting the position of the grating blade 2.

[0052] Specifically, Figure 3In one exemplary case shown, assuming the signal emitted by the first sensor 31 and the second sensor 32 when they are opposite to the first positioning part 41 is 1, and the signal emitted by the first sensor 31 and the second sensor 32 when they are opposite to the second positioning part 42 is 0, then the grating blade 2 slides forward in the first direction ( Figure 3 When the direction of the solid arrow is in the middle, the composite signal of the first sensor 31 and the second sensor 32 will present a sequence of "11, 01, 00, 10, 11, 01, 00, 10...", which can be regarded as a cycle of "11, 01, 00, 10"; while if the grating blade 2 slides in the opposite direction in the first direction ( Figure 3 When the direction of the dashed arrow is changed, the composite signal from the first sensor 31 and the second sensor 32 will present a sequence of "10, 00, 01, 11, 10, 00, 01, 11...", which can be regarded as a cycle of "11, 10, 00, 01". By comparison, it is easy to see that the sequence order of the composite signal will also change when the sliding direction of the grating blade 2 changes.

[0053] Continuing with the composite signal sequence in the example above, since the width of the first positioning part 41 in the first direction is equal to the width of the second positioning part 42 in the first direction, and since L3 = (n + 0.5)L1, in the aforementioned cyclic sequences of "11, 01, 00, 10" and "11, 10, 00, 01", the width of the region of the grating blade 2 corresponding to each composite signal in the first direction is equal. Under these conditions, to calculate the moving distance of the grating blade 2 over a period of time, it is only necessary to multiply the number of composite signals in that period by the width of the region of the grating blade 2 corresponding to each composite signal in the first direction. This configuration makes the calculation of the moving distance of the grating blade 2 more regular and easier to solve, and also helps to improve the signal processing speed of the upper controller.

[0054] As an optional implementation, L1, L2, and L3 also satisfy: L3 = 1.5L1. With this ratio, on the one hand, it can ensure that there is a certain distance between the first sensor 31 and the second sensor 32, which can reduce the risk of excessive installation difficulty due to the two sensors 3 being too close together. On the other hand, it can reduce the influence of the distance between the first sensor 31 and the second sensor 32 on the range of motion of the detectable position of the grating blade 2.

[0055] Of course, in addition to the four composite signal methods mentioned above, in other possible implementations, the conditions required to detect the position of the grating blade 2 can also be met by three composite signals.

[0056] refer to Figure 4 , Figure 4 This is the second schematic diagram illustrating the principle of grating blade position detection in this application. Figure 4 In the example shown, L1, L2, and L3 satisfy: L1 = 2L2, and L3 = L1. Continuing to assume that the signal emitted by the first sensor 31 and the second sensor 32 when they are opposite the first positioning part 41 is 1, and the signal emitted by the first sensor 31 and the second sensor 32 when they are opposite the second positioning part 42 is 0, then when the grating blade 2 slides forward in the first direction (… Figure 4 When the direction of the solid arrow is indicated, the composite signal from the first sensor 31 and the second sensor 32 will present a sequence of "11, 01, 10, 11, 01, 10...", which can be regarded as a cycle of "11, 01, 10"; while if the grating blade 2 slides in the opposite direction in the first direction (…), Figure 4 When the direction of the dashed arrow is changed, the composite signal from the first sensor 31 and the second sensor 32 will present a sequence of "10, 01, 11, 10, 01, 11...", which can be regarded as a cycle of "11, 10, 01". By comparison, it is easy to see that the sequence order of the composite signal will also change when the sliding direction of the grating blade 2 changes, thus satisfying the conditions required for detecting the position of the grating blade 2.

[0057] Of course, except Figure 3 and Figure 4 Besides the two specific examples shown, there are many other ways to set the first positioning part 41, the second positioning part 42, the first sensor 31 and the second sensor 32 to meet the requirements for detecting the position of the grating blade 2, which will not be listed here.

[0058] As an optional implementation, when specifically configuring the first sensor 31 and the second sensor 32, the first sensor 31 and the second sensor 32 are distance sensors; the top of the grating blade 2 is provided with grooves of equal width arranged evenly at intervals along a first direction, each groove being a first positioning part 41, and the protrusion between two adjacent grooves being a second positioning part 42. When there is an object within the sensing range of the distance sensor, the distance sensor can emit different signals according to the distance to the object. When the first sensor 31 or the second sensor 32 is opposite to a groove, the distance between the first sensor 31 or the second sensor 32 and the bottom of the groove is relatively far; when the first sensor 31 or the second sensor 32 is opposite to the protrusion between two adjacent grooves, the distance between the first sensor 31 or the second sensor 32 and the protrusion is relatively close; thus, the first sensor 31 and the second sensor 32 can emit different signals when opposite to different positioning parts 4.

[0059] The specific form of the distance sensor can be inductive, capacitive, photoelectric, magnetic (when using a magnetic proximity switch, the material of the structural component at the top of the blade needs to be magnetic), or the proximity switch can also be other forms such as fiber optic sensors.

[0060] When specifically forming the groove, the groove can be as follows: Figure 2 The method shown involves directly machining the grating blade 2 at its end, or it can be achieved by fixing a grooved structural component to the end of the grating blade 2. (Reference) Figure 5 , Figure 5 This is a schematic diagram of a structural component with a groove in an embodiment of this application. Figure 5 The structural component shown can be fixed to the top of the grating blade by means of bonding, welding, threaded connection, etc.

[0061] In the embodiment where the first positioning part 41 and the second positioning part 42 are formed by uniformly spaced grooves of equal width, and the first sensor 31 and the second sensor 32 are set as distance sensors, the positioning part 4 is formed only by the shape of the grating blade 2, without the need for additional physical connection between the grating blade 2 and the sensor 3. This has the advantages of simple structure, high structural reliability and easy production.

[0062] When the grating assembly provided in this application is specifically applied to radiotherapy equipment, the grating assembly can be in the form of a single-layer grating, or a double-layer or multi-layer grating. Especially for double-layer high-resolution multi-leaf gratings, the thickness of each grating leaf 2 is relatively thin, which makes it difficult to monitor the position of the grating leaf 2 by physically connecting the grating leaf 2 to the corresponding sensing component. Therefore, the scheme for monitoring the position of the grating leaf 2 provided in this application is particularly suitable for double-layer high-resolution multi-leaf gratings.

[0063] Please refer to the above. Figure 6 , Figure 6 This is a schematic diagram of sensor fastening in an embodiment of this application.

[0064] As an optional implementation, when specifically configuring the first sensor 31 and the second sensor 32, the frame 1 is provided with a fixing sleeve 11, in which the first sensor 31 and / or the second sensor 32 are detachably fixed. Optionally, the first sensor 31 and / or the second sensor 32 can be fixed in the fixing sleeve 11 using various methods such as snap-fit ​​structures or threaded fastening structures. For example... Figure 6 In the example, taking the first sensor 31 as an example, the side wall of the sleeve has a threaded hole, and the threaded push rod 12 passes through the threaded hole. After the first sensor 31 is placed into the fixing sleeve 11, the threaded push rod 12 can be rotated to press against the first sensor 31, thereby securing the first sensor 31 in the fixing sleeve 11. When it is necessary to remove the first sensor 31, the threaded push rod 12 can be rotated in the opposite direction to remove it from the threaded hole, thereby releasing the lock on the first sensor 31.

[0065] With this setup, when a first sensor 31 or a second sensor 32 needs to be replaced or calibrated, it can be done independently without disassembling the entire grating assembly, greatly improving the maintainability of the equipment.

[0066] Please refer to the above. Figure 7 , Figure 7 This is a schematic diagram showing the sensors being staggered along the thickness direction of the grating blades in an embodiment of this application.

[0067] As an optional implementation, the number of grating blades 2 is at least two, and the at least two grating blades 2 are spaced apart along the thickness direction of the grating blades 2; the sensors 3 corresponding to two adjacent grating blades 2 are staggered in the thickness direction of the grating blades 2.

[0068] Specifically, multi-leaf gratings typically consist of a dozen, tens, or even hundreds of grating leaves 2 arranged closely together. To achieve independent position detection for each grating leaf 2, at least two sensors 3 are correspondingly provided for each grating leaf 2. By staggering the sensors 3 corresponding to adjacent grating leaves 2 in the thickness direction of the grating leaf 2, sufficient installation space can be provided for each sensor 3 in the very dense arrangement of the grating leaves 2, reducing the risk of collision caused by the volume of the sensor 3 in the thickness direction of the grating leaf 2, and ensuring that each grating leaf 2 can be equipped with an independent sensor 3.

[0069] When specifically setting up the sensor 3, the sensor 3 is not limited to the arrangement described above where there is a certain interval in the width direction of the grating blade 2. In some other embodiments, the grating blade 2 can overlap with the sensor 3 in the width direction, and the grating blade 2 and the sensor 3 are spaced apart in the thickness direction of the grating blade 2.

[0070] Please refer to the above. Figure 8 , Figure 9 , Figure 10 and Figure 11 and Figure 12 , Figure 8 This is the second overall schematic diagram of the grating assembly in the embodiments of this application. Figure 9 This is a schematic diagram of the first signal transmitter and the first signal receiver in an embodiment of this application. Figure 10 This is a schematic diagram of the baffle in an embodiment of this application. Figure 11 This is one of the schematic diagrams showing the arrangement of the signal transmitter and signal receiver in the embodiments of this application. Figure 12 This is the second schematic diagram showing the arrangement of the signal transmitter and signal receiver in the embodiments of this application.

[0071] As an optional implementation, the grating assembly further includes a support plate 6, which is fixed to the frame 1 and disposed opposite to the top of the grating blades 2. The first sensor 31 includes a first signal transmitter 311 and a first signal receiver 312 fixed to the support plate 6, and the second sensor 32 includes a second signal transmitter 321 and a second signal receiver 322 fixed to the support plate 6. The grating assembly also includes a baffle 5. The first signal transmitter 311, the first signal receiver 312, the second signal transmitter 321, the second signal receiver 322 and the baffle 5 cooperate to achieve the output of different types of signals.

[0072] The first sensor 31 includes a first signal transmitter 311 and a first signal receiver 312 fixed to the support plate 6. The first signal transmitter 311 and the first signal receiver 312 are arranged at intervals relative to each other along the thickness direction of the grating blade 2. Such a first sensor 31 can generate a signal through the photoelectric sensing principle. For example, the first signal transmitter 311 always emits a light signal to the first signal receiver 312. When the first signal transmitter 311 and the first signal receiver 312 are not blocked, the first signal receiver 312 can receive the light signal emitted by the first signal transmitter 311; while when the first signal transmitter 311 and the first signal receiver 312 are blocked, the first signal receiver 312 cannot receive the light signal emitted by the first signal transmitter 311. Based on the two states of whether the first signal receiver 312 receives the light signal emitted by the first signal transmitter 311, the first signal receiver 312 can emit two different signals.

[0073] The second sensor 32 includes a second signal transmitter 321 and a second signal receiver 322 fixed to the support plate 6. The second signal transmitter 321 and the second signal receiver 322 are arranged at intervals relative to each other along the thickness direction of the grating blade 2. The cooperation method between the second signal transmitter 321 and the second signal receiver 322 can be the same as or similar to the cooperation method of the first signal transmitter 311 and the first signal receiver 312 described above, and will not be repeated here.

[0074] The baffle 5 has a blocking portion 51 for blocking between the first signal transmitter 311 and the first signal receiver 312. The blocking portion 51 is also used to block between the second signal transmitter 321 and the second signal receiver 322. Multiple blocking portions 51 are spaced apart along a first direction. The baffle 5 is fixed to the end of the grating blade 2 facing the support plate 6. In both the thickness and width directions of the grating blade 2, the blocking portions 51 are located between the first signal transmitter 311 and the first signal receiver 312, and between the second signal transmitter 321 and the second signal receiver 322. Thus, when the grating blade 2 moves along the first direction, the baffle 5 moves along the first direction with the grating blade 2, and the blocking portions 51 intermittently block between the first signal receiver 312 and the first signal transmitter 311, and intermittently block between the second signal receiver 322 and the second signal transmitter 321, so that the sensor 3 intermittently emits two signals.

[0075] That is, for the baffle 5 fixed to the grating blade 2, the blocking part 51 can serve as the first positioning part 41, and the interval area between adjacent blocking parts 51 can serve as the second positioning part 42. When the blocking part 51 moves between the first signal transmitter 311 and the first signal receiver 312, it is equivalent to the first positioning part 41 being opposite to the first sensor 31; when the interval area between adjacent blocking parts 51 moves between the first signal transmitter 311 and the first signal receiver 312, it is equivalent to the second positioning part 42 being opposite to the first sensor 31. When the blocking part 51 moves between the second signal transmitter 321 and the second signal receiver 322, it is equivalent to the first positioning part 41 being opposite to the second sensor 32; when the interval area between adjacent blocking parts 51 moves between the second signal transmitter 321 and the second signal receiver 322, it is equivalent to the second positioning part 42 being opposite to the second sensor 32.

[0076] Each grating blade 2 is equipped with a first sensor 31 and a second sensor 32, which correspond to a first signal receiver 312 and a second signal receiver 322. The signals emitted by the first signal receiver 312 and the second signal receiver 322 can be combined into a composite signal. The specific method of forming the composite signal and how to determine the position of the grating blade 2 through the composite signal can be found in the above description, and will not be repeated here.

[0077] By using the first signal transmitter 311, the first signal receiver 312, the second signal transmitter 321, and the second signal receiver 322 in conjunction with the baffle 5 to generate a composite signal, the direct contact between the sensor 3 and the top of the grating blade 2 can be avoided. This reduces the risk of wear between the sensor 3 and the grating blade 2 causing a decrease in the position detection accuracy of the grating blade 2, and also reduces the risk of damage to the sensor 3 due to friction.

[0078] As an optional implementation, in the direction where the grating blade 2 points towards the carrier plate 6, there is a gap between the first signal transmitter 311 and the carrier plate 6, and the edge of the blocking portion 51 near the carrier plate 6 is located within the gap between the first signal transmitter 311 and the carrier plate 6; in the direction where the grating blade 2 points towards the carrier plate 6, there is a gap between the second signal transmitter 321 and the carrier plate 6, and the edge of the blocking portion 51 near the carrier plate 6 is located within the gap between the second signal transmitter 321 and the carrier plate 6. Here, the direction where the grating blade 2 points towards the carrier plate 6 is the width direction of the grating blade 2. That is, the edge of the blocking portion 51 on the side near the carrier plate 6 extends beyond the edges of the first signal transmitter 311 and the second signal transmitter 321 in the width direction of the grating blade 2, and is spaced apart from the carrier plate 6.

[0079] The shielding part 51 configured in this way ensures, on the one hand, that the shielding part 51 can completely block the first signal transmitter 311 and the second signal transmitter 321, so that the signals emitted by the first signal receiver 312 and the second signal receiver 322 can alternate intermittently. It also provides a certain tolerance for assembly errors between the shielding part 51 and the grating blade 2. Even if there are certain assembly errors between the shielding part 51 and the grating blade 2, between the grating blade 2 and the frame 1, between the support plate 6 and the frame 1, between the first signal transmitter 311 and the support plate 6, and between the second signal transmitter 321 and the support plate 6 in the width direction, the part of the shielding part 51 located within the interval between the first signal transmitter 311 or the second signal transmitter 321 and the support plate 6 can ensure that the shielding part 51 can completely block the first signal transmitter 311 and the second signal transmitter 321 within a certain error accumulation range. On the other hand, the interval between the upper edge of the shielding part 51 and the support plate 6 can also reduce the risk of interference between the shielding part 51 and the support plate 6 due to assembly errors.

[0080] As an optional implementation, the carrier plate 6 is a circuit board, and a capacitor 7 is provided between the first signal transmitter 311 and the circuit board, and / or, a capacitor 7 is provided between the first signal receiver 312 and the circuit board; a capacitor 7 is provided between the second signal transmitter 321 and the circuit board, and / or, a capacitor 7 is provided between the second signal receiver 322 and the circuit board. Figure 9The illustration shows a scenario where a capacitor is placed between the first signal receiver 312 and the circuit board. Specifically, a low-capacitance capacitor 7 (e.g., 1pF) can be selected. The capacitor 7's characteristic of isolating direct current reduces the risk of interference to the first signal receiver 312 and / or the first signal transmitter 311, as well as the risk of interference to the second signal receiver 322 and / or the second signal transmitter 321. Of course, in some other embodiments, other non-conductive materials can be used between the first signal receiver 312 and / or the first signal transmitter 311 and the circuit board, and other non-conductive materials can be used between the second signal receiver 322 and / or the second signal transmitter 321 and the circuit board.

[0081] As an optional implementation, when specifically setting the baffle 5, the baffle 5 also includes a connecting strip 52, and multiple blocking parts 51 are fixedly connected to the connecting strip 52; the connecting strip 52 is fixedly connected to the grating blade 2. Specifically, the connecting strip 52 and the blocking parts 51 can be integrally formed, or they can be manufactured separately and then fixedly connected as a whole. The connecting strip 52 and the grating blade 2 can be fixedly connected by means of adhesive, snap-fit, threaded connection, etc. In specific fixing, the connecting strip 52 can be fixed to the end face in the width direction of the grating blade 2, or it can be fixed to the end of the side face in the thickness direction of the grating blade 2. When manufacturing and assembling the grating blades 2 and the baffles 5, the connecting strip 52 and all the blocking parts 51 can be directly machined from a single piece of material, or all the blocking parts 51 can be assembled to the connecting strip 52 first, and then the baffles 5 can be fixed to the grating blades 2 as a whole. With this configuration, the mutual positioning of all the blocking parts 51 is completed during the process of fixing the blocking parts 51 to the connecting strip 52. When assembling the baffles 5 as a whole, it is only necessary to ensure the alignment accuracy between the connecting strip 52 and the grating blades 2 to ensure the alignment accuracy of all the blocking parts 51 relative to the grating blades 2. This simplifies the assembly and alignment process of the blocking parts 51 and the grating blades 2 and reduces the assembly difficulty of the baffles 5 and the grating blades 2.

[0082] When the first sensor 31 includes a first signal transmitter 311 and a first signal receiver 312, and the second sensor includes a second signal transmitter 321 and a second signal receiver 322, the sensors 3 corresponding to two adjacent grating blades 2 can also be staggered in the thickness direction of the grating blades 2. See details for further information. Figure 11As illustrated, the first signal transmitter 311 and the first signal receiver 312 of the first sensor 31 corresponding to one grating blade 2 can be considered as a combination. This combination, along with the combination formed by the first signal transmitter 311 and the first signal receiver 312 of the first sensor 31 corresponding to another grating blade 2, are staggered in the thickness direction of the grating blade 2. The arrangement of the second sensor 32 can be the same as or similar to that of the first sensor 31, and will not be described further here.

[0083] As an optional implementation method, refer to Figure 12 When specifically setting up the sensor 3, the sensors 3 corresponding to two adjacent grating blades 2 satisfy the following: the first signal transmitter 311, the first signal receiver 312, the second signal transmitter 321, and the second signal receiver 322 of all sensors 3 are arranged in three columns along the first direction. Each first sensor 31 includes a first signal transmitter 311 and a first signal receiver 312, and each second sensor 32 includes a second signal transmitter 321 and a second signal receiver 322. When the first sensors 31 of two adjacent grating blades 2 are arranged along the thickness direction, the two first sensors 31 include two first signal transmitters 311 and two first signal receivers 312, totaling four components. However, by staggering the first sensors 31 of two adjacent grating blades 2, these four components can be arranged in three columns along the first direction.

[0084] Taking two first sensors 31 corresponding to two adjacent grating blades 2 as an example, the first column is provided with a first signal transmitter 311, the second column is arranged with a first signal receiver 312 and a first signal transmitter 311 spaced apart along the first direction, and the third column is provided with a first signal receiver 312. The first signal transmitter 311 in the first column and the first signal receiver 312 in the second column form one first sensor 31, and the first signal receiver 312 in the third column and the first signal transmitter 311 in the second column form another first sensor 31. The three columns form two intervals, and the blocking parts 51 corresponding to two adjacent grating blades 2 are respectively inserted into one of the two intervals. Of course, the above is just an example. In specific implementation, the types of signal receivers and signal transmitters in the three columns are not limited, as long as they can be paired and combined to form a sensor 3. The two second sensors 32 corresponding to two adjacent grating blades 2 can be arranged in the same or similar way as the first sensors 31 described above, which will not be elaborated here.

[0085] The arrangement of the sensors 3 in this way can further compress the space occupied by the first signal transmitter 311, the first signal receiver 312, the second signal transmitter 321 and the second signal receiver 322 corresponding to the multiple grating blades 2 in the thickness direction, thereby facilitating the adaptation to thinner and more closely arranged grating blades 2.

[0086] This application also provides a radiotherapy device, which includes any of the grating components described above.

[0087] In the aforementioned radiotherapy equipment, the grating assembly's positioning unit moves relative to the sensor as the grating blades move. This allows the sensor to emit different composite signals. By recording these composite signals, a composite signal sequence can be obtained. The order of the composite signals within this sequence reveals the direction of the grating blades' movement. Combining this with the width of the positioning unit and counting the composite signals, the distance the grating blades have traveled can be determined, thus enabling the detection of the grating blades' position. This method directly obtains the actual position of the grating blades, effectively reducing the impact of transmission system clearances, installation errors, and manufacturing errors on the accuracy of grating blade position detection, thereby improving the accuracy of grating blade position detection.

[0088] As an optional implementation, the radiotherapy device also includes a controller for determining the position of the grating blades based on the composite signal sequence during their movement. The specific method for determining the position of the grating blades based on the composite signal sequence during their movement can be found above and will not be repeated here.

[0089] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A grating assembly, characterized in that, include: Frame, grating blades, and at least two sensors; among which, The grating blade is slidably disposed on the frame and can slide back and forth along the first direction; the top end of the grating blade has at least two types of positioning parts alternately arranged along the first direction; at least two of the sensors are spaced apart on the frame along the first direction. When the grating blades move to different positioning positions and are opposite the sensor, the sensor emits different signals; At the same time, the signals from at least two of the sensors form a composite signal, and the composite signal has at least three types.

2. The grating assembly according to claim 1, characterized in that, The at least two of the sensors include a first sensor and a second sensor, and the at least two of the positioning units include a first positioning unit and a second positioning unit.

3. The grating assembly according to claim 2, characterized in that, The width of the first positioning part in the first direction is L1, the width of the second positioning part in the first direction is L2, and the distance between the first sensor and the second sensor is L3. L1, L2, and L3 satisfy: L3 is not a positive integer multiple of (L1 + L2).

4. The grating assembly according to claim 3, characterized in that, L1, L2, and L3 also satisfy: L1 = L2, and L3 = (n + 0.5)L1, where n is an integer not less than 0.

5. The grating assembly according to claim 4, characterized in that, L1, L2, and L3 also satisfy: L3 = 1.5L1.

6. The grating assembly according to claim 4, characterized in that, The top of the grating blade is provided with grooves of equal width that are evenly spaced along the first direction. Each groove is a first positioning part, and the protrusion between two adjacent grooves is a second positioning part. The first sensor and the second sensor are distance sensors.

7. The grating assembly according to claim 6, characterized in that, The frame is provided with a fixing sleeve, and the first sensor and / or the second sensor are detachably fixed in the fixing sleeve.

8. The grating assembly according to claim 4, characterized in that, The grating assembly also includes a support plate, which is fixed to the frame and disposed opposite to the top of the grating blades; The first sensor includes a first signal transmitter and a first signal receiver fixed on the carrier plate, and the first signal transmitter and the first signal receiver are arranged at intervals relative to each other along the thickness direction of the grating blade; The second sensor includes a second signal transmitter and a second signal receiver fixed on the carrier plate, the second signal transmitter and the second signal receiver being arranged at intervals relative to each other along the thickness direction of the grating blade; The grating assembly further includes a baffle, the baffle having blocking portions spaced apart along a first direction; the blocking portions serve as first positioning portions, and the interval region between adjacent blocking portions serves as second positioning portions; as the grating blades move, the blocking portions intermittently block between the first signal receiver and the first signal transmitter, and intermittently block between the second signal receiver and the second signal transmitter, so that the first sensor and the second sensor alternately emit two signals.

9. The grating assembly according to claim 8, characterized in that, In the direction in which the grating blades point toward the carrier plate, there is a gap between the first signal transmitter and the carrier plate, and the edge of the shielding portion near the carrier plate is located within the gap between the first signal transmitter and the carrier plate; In the direction in which the grating blades point toward the carrier plate, there is a gap between the second signal transmitter and the carrier plate, and the edge of the shielding portion near the carrier plate is located within the gap between the second signal transmitter and the carrier plate.

10. The grating assembly according to claim 9, characterized in that, The carrier plate is a circuit board; A capacitor is provided between the first signal transmitter and the circuit board, and / or a capacitor is provided between the first signal receiver and the circuit board; A capacitor is provided between the second signal transmitter and the circuit board, and / or a capacitor is provided between the second signal receiver and the circuit board.

11. The grating assembly according to claim 8, characterized in that, The baffle also includes a connecting strip, and the plurality of the shielding parts are fixedly connected to the connecting strip; The connecting strip is fixedly connected to the grating blade.

12. The grating assembly according to any one of claims 1 to 11, characterized in that, The number of grating blades is at least two, and the at least two grating blades are spaced apart along the thickness direction of the grating blades; The sensors corresponding to two adjacent grating blades are staggered in the thickness direction of the grating blades.

13. The grating assembly according to claim 12, characterized in that, When the first sensor includes a first signal transmitter and a first signal receiver, and the second sensor includes a second signal transmitter and a second signal receiver, the sensors corresponding to two adjacent grating blades satisfy the following: The first signal transmitter, first signal receiver, second signal transmitter, and second signal receiver of all the aforementioned sensors are arranged in three columns along the first direction.

14. A radiotherapy device, characterized in that, Includes the grating assembly as described in any one of claims 1 to 13.

15. The radiotherapy device according to claim 14, characterized in that, The radiotherapy device also includes a controller, which is used to determine the position of the grating blades based on the composite signal sequence during the movement of the grating blades.

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