A control method for a treatment bed

Abstract

The present invention relates to a control method for a treatment couch. The method comprises the following steps: 1) constructing a base coordinate system with the gantry's rotation center as the origin, then sequentially establishing coordinate systems for each axis, while simultaneously defining and describing the positions and orientations of the X, Y, and Z axes relative to the coordinate systems; 2) controlling the motion of the translational component; and 3) controlling the motion of the rotational component. This method addresses the treatment needs of patients with head and body lesions. The treatment process minimizes treatment harm to the patient, avoids damage to vital tissues and organs, and enhances the therapeutic efficacy of gamma knife radiotherapy.

Description

Technical Field

[0001] The present invention relates to the medical field, and in particular to a control method for a treatment bed. Background Art

[0002] The current Gamma Knife is a large-scale medical device that integrates stereotactic and radiosurgery techniques, primarily used to treat brain diseases and body tumors. Its treatment principle is similar to the focusing process of a magnifying glass, where the radiation beams are cross-superimposed to deliver a high dose to the lesion while the surrounding normal tissue receives a lower dose, thereby reducing radiation damage to normal tissue. To enhance the precision of radiotherapy equipment, most Gamma Knife devices are equipped with a dedicated treatment bed.

[0003] Currently, the treatment couch used in Gamma Knife radiotherapy is a three-dimensional couch. This means the patient support portion of the couch can translate along three linear axes: X, Y, and Z. This allows the patient to be carried in three dimensions, allowing the patient's lesion to be moved to the focal point of the radiotherapy device for treatment. However, during treatment of some lesions, the radiation may need to pass through the patient's vital organs to reach the lesion. For example, when treating a head tumor, the lesion may be located behind the optic nerve, and radiation exposure to the lesion could damage the patient's optic nerve.

[0004] In order to avoid damage to the patient's important tissues and organs, the treatment couch needs to be able to rotate around three linear axes, that is, the treatment couch should have six-dimensional movement. On the basis of translational movement along the three linear axes X, Y, and Z, it should also have three rotations around the linear axes Xt, Yt, and Zt. In this way, the rays can focus on the lesion while bypassing the important tissues and organs at the lesion site, thereby effectively reducing and avoiding damage to the patient and improving the treatment effect.

[0005] Therefore, it is necessary to provide a new motion mechanism and motion control method for a gamma knife treatment bed to achieve therapeutic effects on patients while reducing treatment damage and avoiding treatment damage to patients' important tissues and organs. Summary of the Invention

[0006] To solve the above-mentioned technical problems existing in the background technology, the present invention provides a control method for a treatment couch. Specifically, the control method is designed to meet the treatment needs of patients with head and body lesions. The treatment process reduces treatment damage to the patient, avoids treatment damage to the patient's important tissues and organs, and improves the treatment effect of the gamma knife.

[0007] The technical solution of the present invention is: the present invention is a control method for a treatment bed, which is special in that the method includes the following steps:

[0008] 1) Construct the base coordinate system with the rotation center of the Gamma Knife six-dimensional treatment bed as the origin, and then establish the coordinate system of each axis in turn, and define the position and direction of XT, YT, and ZT relative to the coordinate system;

[0009] 2) The Z-axis assembly of the Gamma Knife six-dimensional treatment bed is a double-layer lifting structure, which is divided into the Z1 axis and the Z2 axis. The middle lifting seat is fixed on the guide rail of the vertical support to form the Z1 axis that can be lifted and lowered. The XZ cross support plate is fixed on the guide rail of the middle lifting seat to form the Z2 axis that can be lifted and lowered. The entire structure ensures the parallelism and verticality accuracy during the Z-axis transmission process through the double-layer lifting mechanism, and meets the requirements of the Gamma Knife treatment bed for a large Z-direction travel. The world coordinates of the patient's lesion site are defined as P(x, y, z). The translational motion of position P on the Z axis is achieved by controlling the lifting motion of the Z1 axis and the Z2 axis respectively, which can be expressed as:

[0010]

[0011] [x′, y′, z′, 1] is the target position P(z)′, (tx, ty, tz) is the lifting displacement, where tx = 0, ty = 0; the displacement increment of the single-layer mechanism on the Z axis is expressed as:

[0012]

[0013] 3) The X-axis assembly of the Gamma Knife six-dimensional treatment bed includes an X-axis guide rail and an overhanging base. The overhanging base forms an X-axis that can move left and right along the X-axis guide rail on the XZ cross support plate. The servo motor and precision lead screw drive ensure the transmission accuracy of the X-axis. The patient's lesion position P moves in the positive and negative directions of the X-axis along the X-axis guide rail to the position P(x)′ = (x′, y′, z′), which can be expressed as:

[0014]

[0015] Where (tx, ty, tz) is the translation amount, ty = 0, tz = 0;

[0016] 4) The Gamma Knife six-dimensional treatment bed has a double-layer translation structure. The special feature of this structure is that it ensures the transmission accuracy of the Y axis and solves the need for a large Y-axis travel of the Gamma Knife treatment bed. The Y axis, which can move back and forth, is composed of a Y-axis guide rail and a lower plate. The upper and lower layers are installed between the two layers, and the middle is divided by a telescopic cavity to form the Y1 axis and the Y2 axis. When the lesion position P moves back and forth on the Y axis to the position P(y)′=(x′, y′, z′), its coordinates can be expressed as:

[0017]

[0018] Where tx = 0, tz = 0; the motion displacement of the single-layer translation structure Y1 and Y2 is expressed as:

[0019]

[0020] 5) The X-axis and Y-axis rotation components of the Gamma Knife six-dimensional treatment bed include a middle plate, a rotating component, a sliding component, and a transmission component. The rotating component and the transmission component are installed between the lower plate and the middle plate. Two transmission components and one rotating component form a three-point support structure. Each set of transmission components is connected to one set of sliding components. When the lead screw in the transmission component rotates, it drives the sliding component to move and then realizes the rotation of the middle plate around the X axis or around the Y axis. The lesion reference position P of the head body rotates in the positive direction around the X axis. The lead screw rotates at an angle of θ. The target reference position P to be rotated axz The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship:

[0021]

[0022] Rotate in the negative direction around the X axis, the screw rotates by an angle of θ, and the target reference position to be rotated is P axf The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship:

[0023]

[0024] The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions can be expressed as:

[0025] Δx - =P axf -P

[0026] Δx + =P axz -P

[0027] The lesion reference position P of the head body rotates in the positive direction around the Y axis, and the screw rotates at an angle of θ. The target reference position P to be rotated ayz The rotation vector T matrix of the (x′, y′, z′) position relative to the initial position P satisfies the following relationship:

[0028]

[0029] Rotate in the negative direction around the Y axis, the screw rotation angle is θ, and the target reference P to be rotated ayf The rotation vector T matrix of the (x′, y′, z′) position relative to the initial position P satisfies the following relationship:

[0030]

[0031] The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions around the Y axis can be expressed as:

[0032] Δx- =P ayf -P

[0033] Δx + =P ayz -P

[0034] 6) The Z-axis rotation assembly of the Gamma Knife six-dimensional treatment bed includes an upper plate and a Zt-axis transmission assembly, wherein the Zt-axis transmission assembly is installed between the middle plate and the upper plate. Driven by the Z-axis rotation assembly, the upper plate can rotate around the Z-axis along the circular guide rail; the upper plate rotates forward along the circular guide rail by an angle θ to the target position P azz (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship:

[0035]

[0036] Rotate in the negative direction by angle θ to the target position P azf (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship:

[0037]

[0038] The upper plate rotates around the Z axis in the positive and negative directions by an angle θ. The displacement increment of the target position of the lesion reference position relative to the initial position can be expressed as:

[0039] Δx - =P azf -P

[0040] Δx + =P azz -P.

[0041] Furthermore, the specific steps of step 1) are as follows: taking the center of rotation of the frame as the origin, using a right-handed system to construct a base space coordinate system, establishing X, Y, and Z space coordinates, and establishing a Yt axis rotating along the X axis, an Xt axis rotating along the Y axis, and a Zt axis rotating along the Z axis on the basis of ZYZ;

[0042] Furthermore, the double-layer lifting structure in step 2) includes a base, a vertical support, a middle-layer lifting seat, a Z1-axis guide rail, a Z1-axis drive, a Z2-axis guide rail, a Z2-axis drive, and an XZ cross-pallet. The vertical support is arranged on the base, and the Z1-axis guide rail is vertically arranged on the vertical support. The middle-layer lifting seat is arranged on the Z1-axis guide rail through a first slider, and the Z1-axis drive is arranged on the back of the middle-layer lifting seat and can drive the middle-layer lifting seat to move vertically on the vertical support. The Z2-axis guide rail is vertically arranged in front of the middle-layer lifting seat. The XZ cross-pallet is arranged on the Z2-axis guide rail through a second slider, and the Z2-axis drive is arranged in front of the middle-layer lifting seat and can drive the XZ cross-pallet to move vertically on the middle-layer lifting seat.

[0043] Furthermore, the X-axis assembly in step 3) includes an X-axis guide rail and a cantilever seat. The X-axis guide rail is arranged horizontally in front of the XZ cross support plate. The cantilever seat is arranged on the X-axis guide rail through a third slider. The X-axis drive is arranged in front of the XZ cross support plate and can drive the cantilever seat to move horizontally on the XZ cross support plate.

[0044] Furthermore, the double-layer translation structure in step 4) includes a Y-axis guide rail and a lower plate. The Y-axis guide rail is provided on the overhang seat. The lower plate is set on the Y-axis guide rail through the fourth slider. The Y-axis drive is set on the overhang seat and can drive the lower plate to move horizontally along the Y-axis direction on the overhang seat.

[0045] Furthermore, the X-axis and Y-axis rotation components in step 5) include a middle plate, a rotating component, a sliding component and a transmission component. The sliding component and the rotating component are arranged between the middle plate and the lower plate, the sliding component is connected to the transmission component, and the lower plate is arranged on the Y-axis guide rail through the fourth slider. The sliding component includes an inclined surface connector, a first guide rail, a second guide rail, a special-shaped connector, a self-aligning ball bearing, a first bearing seat, a bearing end cover, a locking nut and a third guide rail; the first guide rail is arranged on the lower plate, the inclined surface connector is arranged on the first guide rail and can slide along the first guide rail, the second guide rail is arranged on the inclined surface of the inclined surface connector, the special-shaped connector is arranged on the second guide rail and can slide along the second guide rail, the first bearing seat is arranged on the special-shaped connector, a self-aligning ball bearing is arranged in the first bearing seat, a bearing end cover is arranged above it, the bearing end cover is connected to the first bearing seat through a locking nut, a third guide rail is arranged above the bearing end cover, and the middle plate is arranged On the third guide rail, the transmission assembly includes a servo motor, a reducer, a coupling, a support seat, a first bearing, a screw, a second bearing, a second bearing seat and a screw nut. One end of the screw is connected to the second bearing, and the other end passes through the first bearing and is connected to the coupling. The coupling is connected to the servo motor through the reducer. The second bearing is arranged on the lower plate through the second bearing seat, and the first bearing is arranged on the lower plate through the support seat. A screw nut is provided on the screw, and the screw is connected to the bevel connector through the screw nut. The rotating assembly includes 4 third bearing seats, 4 third bearings and a cross shaft. The 4 third bearing seats are respectively arranged at the front, rear, left and right 4 shaft ends of the cross shaft. The two third bearing seats arranged at the front and rear are connected to the middle plate, and the two third bearing seats arranged on the left and right are connected to the lower plate. The 4 shaft ends of the cross shaft are respectively equipped with a third bearing, and the 4 shaft ends of the cross shaft are respectively connected to the 4 third bearing seats through 4 third bearings.

[0046] Furthermore, the Z-axis rotation assembly in step 6) includes an upper plate and a Zt-axis transmission assembly, the Zt-axis transmission assembly is installed between the middle plate and the upper plate, the Zt rotation assembly includes an arc guide rail and a Zt transmission, the Zt transmission includes a reducer, a servo motor component, a pinion component and an arc gear, the reducer passes through the middle plate, the input end of the reducer is installed with a servo motor component, the output shaft of the reducer is installed with a pinion component, the arc gear is fixedly installed below the upper plate and meshes with the pinion component, the arc guide rail includes an arc guide rail and a slide, the slide is arranged on the arc guide rail, the arc guide rail is arranged on the upper plate, and the slide is arranged on the middle plate,

[0047] Furthermore, there are two groups of sliding components, which are symmetrically arranged on both sides of the lower plate. There are two corresponding groups of transmission components, which are respectively arranged on the inner sides of the two groups of sliding components. The rotating component also includes 4 locking nuts and 4 bearing end covers. The 4 locking nuts are respectively assembled on the 4 shaft ends of the cross shaft to lock the third bearing to the cross shaft. A bearing end cover is set on each third bearing seat.

[0048] Furthermore, the circular arc guide rail is divided into four sections, which are distributed on the same circumference.

[0049] Furthermore, the overhang seat is a cavity-shaped part with an upper opening and a front end opening, and the inner bottom surface of the cavity has a horizontal plane.

[0050] The control method for the treatment couch provided by this invention utilizes three linear displacement axes and three rotational motions. All axes are driven by servo motors, driven by a precision transmission mechanism, and positioned and guided by a precision positioning and guidance mechanism. Testing has demonstrated that the spatial positioning accuracy of lesions can reach within 0.5 mm, meeting the requirements of current Gamma Knife treatments. Furthermore, the three rotational motions enable lesion positioning and rotation around the center by ±3°, enabling patient swaying. This allows treatment to avoid nearby vital tissues and organs, resulting in optimal treatment outcomes. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 This is a schematic diagram of the method of the present invention

[0052] Figure 2 2. It is a schematic structural diagram of a six-dimensional Gamma Knife treatment couch according to an application embodiment of the present invention;

[0053] Figure 3 It is a schematic structural diagram of a rotating bed of the present invention;

[0054] Figure 4 It is a schematic diagram of the arrangement of the sliding assembly, the transmission assembly and the rotating assembly on the rotary bed of the present invention;

[0055] Figure 5 It is a schematic structural diagram of the sliding assembly of the present invention;

[0056] Figure 6 It is a schematic structural diagram of the transmission assembly of the present invention;

[0057] Figure 7 is a schematic diagram of a rotating assembly of the present invention;

[0058] Figure 8 This is a schematic diagram of the installation of the Zt rotating assembly of the present invention;

[0059] Figure 9 It is a schematic diagram of the arrangement of the Zt rotating assembly and the arc guide rail of the present invention.

[0060] The following are the descriptions of the reference numerals:

[0061] 1. Base; 2. Vertical support; 3. Middle lift seat; 4. Z1 axis guide rail; 5. Z2 axis guide rail; 6.

[0062] Z2 axis drive; 7, X, Z cross pallet; 8, X axis guide rail; 9, X axis drive; 10, overhang seat; 11,

[0063] Y-axis guide rail; 12. Y-axis drive; 13. Rotating bed; 14. Support plate; 15. Positioning bed;

[0064] 13.1, lower plate; 13.2, middle plate; 13.3, upper plate; 13.4, curved guide rail; 13.5, Zt rotating assembly; 13.6, sliding assembly; 13.7, transmission assembly; 13.8, rotating assembly; 13.9, bearing seat;

[0065] 13.5.1 Reducer, 13.5.2 Pinion, 13.5.3 Circular arc gear, 13.5.4 Servo motor;

[0066] 13.6.1. Inclined connector; 13.6.2. First guide rail; 13.6.3. Second guide rail; 13.6.4. Special-shaped connector; 13.6.5. Self-aligning ball bearing; 13.6.6. First bearing seat; 13.6.7. Bearing end cap; 13.6.8. Lock nut; 13.6.9. Third guide rail;

[0067] 13.7.1. Servo motor; 13.7.2. Reducer; 13.7.3. Coupling; 13.7.4. Support seat; 13.7.5. First bearing; 13.7.6. Lead screw; 13.7.7. Second bearing; 13.7.8. Second bearing seat; 13.7.9. Lead screw nut;

[0068] 13.8.1. Third bearing seat; 13.8.2. Cross shaft; 13.8.3. Third bearing; 13.8.4. Locking nut; 13.8.5. Bearing end cover. DETAILED DESCRIPTION

[0069] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0070] See also Figure 1 The steps of the specific embodiment of the method of the present invention are as follows:

[0071] 1) Construct the base coordinate system with the rotation center of the Gamma Knife six-dimensional treatment bed as the origin, and then establish the coordinate system of each axis in turn, and define the position and direction of XT, YT, and ZT relative to the coordinate system;

[0072] Specifically, the base space coordinate system is constructed with the frame rotation center as the origin using the right-hand system to establish the X, Y, and Z space coordinates. On the basis of ZYZ, the Yt axis rotating along the X axis, the Xt axis rotating along the Y axis, and the Zt axis rotating along the Z axis are established.

[0073] 2) The Z-axis assembly of the Gamma Knife six-dimensional treatment bed is a double-layer lifting structure, which is divided into the Z1 axis and the Z2 axis. The middle lifting seat is fixed on the guide rail of the vertical support to form the Z1 axis that can be lifted and lowered. The XZ cross support plate is fixed on the guide rail of the middle lifting seat to form the Z2 axis that can be lifted and lowered. The entire structure ensures the parallelism and verticality accuracy during the Z-axis transmission process through the double-layer lifting mechanism, and meets the requirements of the Gamma Knife treatment bed for a large Z-direction travel. The world coordinates of the patient's lesion site are defined as P (x, y, z). The translational motion of position P on the Z axis is achieved by controlling the lifting motion of the Z1 axis and the Z2 axis respectively, which can be expressed as:

[0074]

[0075] [x′, y, z′, 1] is the target position P(z)′, (tx, ty, tz) is the lifting displacement, where tx = 0, ty = 0; the displacement increment of the single-layer mechanism on the Z axis is expressed as:

[0076]

[0077] 3) The X-axis assembly of the Gamma Knife six-dimensional treatment bed includes an X-axis guide rail and an overhanging base. The overhanging base forms an X-axis that can move left and right along the X-axis guide rail on the XZ cross support plate. The servo motor and precision lead screw drive ensure the transmission accuracy of the X-axis. The patient's lesion position P moves in the positive and negative directions of the X-axis along the X-axis guide rail to the position P(x)′ = (x′, y′, z′), which can be expressed as:

[0078]

[0079] Where (tx, ty, tz) is the translation amount, ty = 0, tz = 0;

[0080] 4) The Gamma Knife six-dimensional treatment bed has a double-layer translation structure. The special feature of this structure is that it ensures the transmission accuracy of the Y axis and solves the need for a large Y-axis travel of the Gamma Knife treatment bed. The Y axis, which can move back and forth, is composed of a Y-axis guide rail and a lower plate. The upper and lower layers are installed between the two layers, and the middle is divided by a telescopic cavity to form the Y1 axis and the Y2 axis. When the lesion position P moves back and forth on the Y axis to the position P(y)′=(x′, y′, z′), its coordinates can be expressed as:

[0081]

[0082] Where tx = 0, tz = 0; the motion displacement of the single-layer translation structure Y1 and Y2 is expressed as:

[0083]

[0084] 5) The X-axis and Y-axis rotation components of the Gamma Knife six-dimensional treatment bed include a middle plate, a rotating component, a sliding component, and a transmission component. The rotating component and the transmission component are installed between the lower plate and the middle plate. Two transmission components and one rotating component form a three-point support structure. Each set of transmission components is connected to one set of sliding components. When the lead screw in the transmission component rotates, it drives the sliding component to move and then realizes the rotation of the middle plate around the X axis or around the Y axis. The lesion reference position P of the head body rotates in the positive direction around the X axis. The lead screw rotates at an angle of θ. The target reference position P to be rotated axz =(x′, y′, z′) The rotation vector T matrix relative to the initial position P satisfies the following relationship:

[0085]

[0086] Rotate in the negative direction around the X axis, the screw rotates by an angle of θ, and the target reference position to be rotated is P axf The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship:

[0087]

[0088] The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions can be expressed as:

[0089] Δx - =P axf -P

[0090] Δx + =P axz -P

[0091] The lesion reference position P of the head body rotates in the positive direction around the Y axis, and the screw rotates at an angle of θ. The target reference position P to be rotated ayz The rotation vector T matrix of the (x′, y′, z′) position relative to the initial position P satisfies the following relationship:

[0092]

[0093] Rotate in the negative direction around the Y axis, the screw rotation angle is θ, and the target reference P to be rotated ayf The rotation vector T matrix of the (x′, y′, z′) position relative to the initial position P satisfies the following relationship:

[0094]

[0095] The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions around the Y axis can be expressed as:

[0096] Δx - =P ayf -P

[0097] Δx + =P ayz -P

[0098] 6) The Z-axis rotation assembly of the Gamma Knife six-dimensional treatment bed includes an upper plate and a Zt-axis transmission assembly, wherein the Zt-axis transmission assembly is installed between the middle plate and the upper plate. Driven by the Z-axis rotation assembly, the upper plate can rotate around the Z-axis along the circular guide rail; the upper plate rotates forward along the circular guide rail by an angle θ to the target position P azz (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship:

[0099]

[0100] Rotate in the negative direction by angle θ to the target position P azf (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship:

[0101]

[0102] The upper plate rotates around the Z axis in the positive and negative directions by an angle θ. The displacement increment of the target position of the lesion reference position relative to the initial position can be expressed as:

[0103] Δx - =P azf -P

[0104] Δx + =P azz -P.

[0105] See also Figure 2The structure of the gamma knife six-dimensional treatment bed in a specific application embodiment of the present invention includes a base 1, a vertical support 2, a middle lifting seat 3, a Z1-axis guide rail 4, a Z2-axis guide rail 5, a Z-axis drive 6, an XZ cross support plate 7, an X-axis guide rail 8, an X-axis drive 9, an overhang seat 10, a Y-axis guide rail 11, a Y-axis drive 12, a rotating bed 13, a support plate 14, and a positioning bed 15;

[0106] The base 1 is at the bottom of the structure of the present invention. The base 1 is placed horizontally and connected to the foundation. The base 1 provides a platform for other components installed on it. The vertical support 2 is fixedly mounted on the base 1. The front of the vertical support 2 has a vertical plane for installing the Z1-axis guide rail 4. At the same time, a set of Z1-axis drives are also installed in front of the vertical support 2. The Z1-axis drive is blocked and cannot be seen behind the middle-level lifting seat 3. The Z1-axis guide rail 4 is a guide rail in the Z1-axis direction and is vertically mounted on the vertical support 2. A first slider is installed on the back of the middle-level lifting seat 3. The middle-level lifting seat 3 can move in the Z-axis direction (vertical direction) along the Z1-axis guide rail 4 through the first slider behind it, driven by the Z1-axis drive. The front of the middle lift seat 3 is mounted with a Z2-axis guide rail 5 and a Z2-axis drive 6. The Z2-axis guide rail 5 is also mounted vertically. A second slider is mounted behind the XZ cross support 7. Driven by the Z2-axis drive 6, the XZ cross support 7 can move in the Z-axis direction (vertical) along the Z2-axis guide rail 5. The front of the XZ cross support 7 is mounted with an X-axis guide rail 8 and an X-axis drive 9. The back of the cantilever seat 10 is mounted with a third slider. Driven by the X-axis drive 9, the cantilever seat 10 can move in the X-axis direction (horizontal) along the X-axis guide rail 8. The cantilever seat 10 is a cavity-shaped component with an upper opening and a front end. The bottom surface of the cavity has a horizontal plane, on which the Y-axis guide rail 11 and the Y-axis drive 12 are mounted in the Y direction. A fourth slider is mounted at the bottom of the rotary bed 13. Driven by the Y-axis drive 12, the rotary bed 13 can move in the Y direction along the Y-axis guide rail 11. A support plate 14 is fixedly mounted on the top of the rotating bed 13. A positioning bed 15 is fixedly mounted on top of the support plate 14. This bed provides a platform for the patient to lie flat and an N-ray device for tumor localization. It also features wings to protect the patient. Stereoscopic positioning devices such as a body positioning frame and a head positioning frame can be mounted on the bed 15. A transmission mechanism is incorporated into the rotating bed 13, enabling the upper plate of the bed 13 to rotate slightly relative to its lower plate in the X, Y, and Z directions.

[0107] The treatment couch of the present invention is capable of movement in the X, Y, and Z directions and small-angle rotation around these three directions. The drive mechanisms for each axis of the couch are precision transmission mechanisms. Combined with the N-line positioning device and the stereotactic positioning device on the couch, the couch can achieve precise spatial positioning of the patient's tumor. Its rotation function around three axes can effectively avoid the patient's sensitive organs during treatment of certain tumors, minimizing harm to the patient.

[0108] See also Figure 3 、 4 The structure of the specific application embodiment of the rotating bed 13 of the present invention includes a lower plate 13.1, a middle plate 13.2, an upper plate 13.3, an arc guide rail 13.4, a Zt rotating component 13.5, a sliding component 13.6, a transmission component 13.7 and a rotating component 13.8.

[0109] The sliding assembly 13.6 and the rotating assembly 13.8 are arranged between the middle plate 13.2 and the lower plate 13.1, the sliding assembly 13.6 is connected to the transmission assembly 13.7, the Zt rotating assembly 13.5 and the arc guide rail 13.4 are arranged between the middle plate 13.2 and the upper plate 13.3, the lower plate 13.1 is arranged on the Y-axis guide rail 11 through the fourth slider, and the support plate 14 is arranged on the upper plate 13.3.

[0110] See also Figure 5 The structure of the specific application embodiment of the sliding assembly 13.6 of the present invention includes an inclined connection member 13.6.1, a first guide rail 13.6.2, a second guide rail 13.6.3, a special-shaped connection member 13.6.4, a self-aligning ball bearing 13.6.5, a first bearing seat 13.6.6, a bearing end cover 13.6.7, a locking nut 13.6.8 and a third guide rail 13.6.9; the first guide rail 13.6.2 is arranged on the lower plate 1, the inclined connection member 13.6.1 is arranged on the first guide rail 13.6.2, and can slide along the first guide rail 13.6.2, and the second guide rail 13.6.3 is arranged on the inclined connection member On the inclined surface of the connecting piece 13.6.1, the special-shaped connecting piece 13.6.4 is arranged on the second guide rail 13.6.3 and can slide along the second guide rail 13.6.3. The first bearing seat 13.6.6 is arranged on the special-shaped connecting piece 13.6.4. The first bearing seat 13.6.6 is provided with a self-aligning ball bearing 13.6.5, and a bearing end cover 13.6.7 is provided above it. The bearing end cover 13.6.7 is connected to the first bearing seat 13.6.6 by a locking nut. A third guide rail 13.6.9 is provided above the bearing end cover 13.6.7, and the middle plate 13.2 is provided on the third guide rail 13.6.9.

[0111] See also Figure 6The structure of the specific application embodiment of the transmission component 13.7 of the present invention includes a servo motor 13.7.1, a reducer 13.7.2, a coupling 13.7.3, a support seat 13.7.4, a first bearing 13.7.5, a screw 13.7.6, a second bearing 13.7.7 and a second bearing seat 13.7.8. One end of the screw 13.7.6 is connected to the second bearing 13.7.7, and the other end passes through the first bearing 13.7.5 and is connected to the coupling 13.7.3 The coupling 13.7.3 is connected to the servo motor 13.7.1 through the reducer 13.7.2, the second bearing 13.7.7 is arranged on the lower plate 13.1 through the second bearing seat 13.7.8, the first bearing 13.7.5 is arranged on the lower plate 13.1 through the support seat 13.7.4, and the screw 13.7.6 is provided with a screw nut 13.7.9, and the screw 13.7.6 is connected to the inclined connecting piece 13.6.1 through the screw nut 13.7.9.

[0112] See also Figure 7 The structure of the specific application embodiment of the rotating assembly 13.8 of the present invention includes four third bearing seats 13.8.1, a cross shaft 13.8.2, four third bearings 13.8.3, four locking nuts 13.8.4 and four bearing end covers 13.8.5; the four third bearing seats 13.8.1 are respectively arranged at the front, rear, left and right ends of the cross shaft 13.8.2, the two third bearing seats 13.8.1 arranged at the front and rear are connected to the middle plate 13.2, and the two third bearing seats 13.8.1 arranged on the left and right are connected to the middle plate 13.2. Connected to the lower plate 13.1, the four ends of the cross shaft 13.8.2 are respectively equipped with a third bearing 13.8.3, and four locking nuts 13.8.3 are respectively assembled on the four ends of the cross shaft 13.8.2 to lock the third bearing 13.8.3 to the cross shaft 13.8.2. The four ends of the cross shaft 13.8.2 are respectively connected to the four third bearings 13.8.3 and the four third bearing seats 13.8.1. A bearing end cover 13.8.5 is arranged on each third bearing seat 13.8.1.

[0113] Each of the sliding assemblies 13.6 and transmission assemblies 13.7 consists of two groups, symmetrically arranged on either side of the lower plate 13.1. Each group of transmission assemblies 13.7 is connected to a group of sliding assemblies 13.6, and the transmission assemblies 13.7 drive the sliding assemblies 13.6. The cross shaft 13.8.2 has two axes intersecting at 90 degrees, forming four shaft ends. The third bearing blocks 13.8.1 have four pieces, and the four third bearing blocks 13.8.1 are respectively connected to the four shaft ends of the cross shaft 13.8.2. Two of the coaxially mounted third bearing blocks 13.8.1 are connected to the lower plate 13.1, while the other two coaxially mounted third bearing blocks 13.8.1 are connected to the middle plate 13.2. In other words, 13.2 and the lower plate 13.1, connected by the third bearing blocks 13.8.1, form a hinge connection in two directions through the cross shaft 13.8.2.

[0114] See also Figure 8 The structure of the specific application embodiment of the Zt rotating component 13.5 of the present invention includes a reducer 13.5.1, a servo motor component 13.5.4, a small gear component 13.5.2 and an arc gear 13.5.3. There is a hole on the middle plate 13.2, and the reducer 13.5.1 is fixedly installed on the middle plate 13.2 through the hole. The servo motor component 13.5.4 is installed at the input end of the reducer 13.5.1, and the small gear component 13.5.2 is installed on the output shaft of the reducer 13.5.1. The arc gear 13.5.3 is fixedly installed under the upper plate 13.3.

[0115] See also Figure 9 The arc guide rail 13.4 of the present invention comprises a circular arc guide rail and a slide, which is mounted on the circular arc guide rail. In this embodiment, the arc guide rail 13.4 is divided into four sections, which are distributed along the same circumference. The circular arc guide rail of the arc guide rail 13.4 is fixedly mounted on the upper plate 13.3, and the slide of the arc guide rail 13.4 is fixedly mounted on the middle plate 13.2. When the servo motor 13.5.4 drives the reducer 13.5.1, the pinion 13.5.2 drives the circular arc gear 13.5.3 to rotate. At this time, the upper plate 13.3 rotates about the Z-axis under the constraint of the arc guide rail 13.4.

[0116] The three linear movements of X, Y and Z of the six-dimensional motion treatment bed adopt a layout structure with superimposed motion mechanisms. The motion mechanism of the bottom layer is the middle-layer lifting seat 3 that moves up and down along the Z1-axis guide rail 4. The movement of the middle-layer lifting seat 3 is realized under the drive of the Z1-axis drive. The structure of the Z1-axis drive is the same as that of the Z2-axis drive 6. The difference is the installation position. The Z1-axis drive mechanism is installed between the middle-layer lifting seat 3 and the vertical support 2. The motion mechanism of the second layer is the XZ cross-support plate 7 that moves up and down along the Z2-axis guide rail 5. The movement of the XZ cross-support plate 7 is driven by the Z2-axis drive 6. The two-layer Z-axis motion can realize a large range of movement (lifting and lowering motion) of the treatment bed along the Z direction.

[0117] A moving mechanism along the X direction is superimposed after the Z-direction moving mechanism. The overhang seat 10 is a mechanism that moves along the X direction. Under the drive of the X-axis drive 9, the overhang seat 10 realizes X-direction movement along the X-axis guide rail 8 fixedly mounted on the XZ cross support plate 7.

[0118] The moving mechanism along the Y axis is followed by the moving mechanism along the X axis. Driven by the Y axis drive 12, the rotating bed 13 moves along the Y axis guide rail 11 fixedly mounted on the overhanging seat 10 to realize the Y axis movement.

[0119] Following the Y-axis is a rotating bed section that can achieve three rotational motions, Xt, Yt, and Zt. The rotating bed section's rotational mechanism around the X-axis and Y-axis is implemented by a rotating assembly 13.8, two sliding assemblies 13.6, and two transmission assemblies 13.7. Two sliding assemblies 13.6 and one rotating assembly 13.8 form a three-point support structure. Each transmission assembly 13.7 is connected to one of the sliding assemblies 13.6. When the lead screw 13.7.6 in the transmission assembly 13.7 rotates, the lead screw nut 13.7.9 connected to the sliding assembly 13.6 will move in the Y direction. The Y-direction movement of the lead screw nut 13.7.9 causes the first bearing seat 13.6.6 to move along the Z-axis, thereby driving the middle plate 13.2 to rotate around the cross shaft 13.8.2. When the lead screws 13.7.6 of the two transmission assemblies 13.7 rotate synchronously in the forward direction, the center plate 13.2 rotates around the cross shaft 13.8.2 about the X-axis. When the lead screws 13.7.6 of the two transmission assemblies 13.7 rotate synchronously in the reverse direction, the center plate 13.2 rotates around the cross shaft 13.8.2 about the Y-axis. Therefore, the two sliding assemblies 13.6, the transmission assembly 13.7, and the rotating assembly 13.8 jointly generate the rotation of the center plate 13.2 about the X-axis and / or the Y-axis. All moving axes are positioned and guided by precision linear or circular guides. The transmission assembly 13.7 uses a precision ball screw and a high-precision planetary reduction drive, and the drive unit is a precision servo motor.

[0120] The present invention features three linear motion axes and three rotational axes. The diagram shows a servo motor drive, a planetary reducer and ball screw transmission, and linear or circular guide rails for positioning. However, the structure is not limited to the drive, transmission, and positioning methods shown in the diagram. Other drive and transmission structures can also include linear motor drive, direct motor drive, belt drive, and rack drive.

[0121] The transmission structure of the rotating bed in the Gamma Knife treatment bed is not limited to the above, and can also be three relatively independently controlled motion units, or three motion units can move in coordination with each other, or any two of the motion units can move in coordination with each other.

[0122] The content of the present invention and the technical content not specifically described in the above embodiments are the same as the prior art.

[0123] The above are only specific embodiments disclosed in the present invention, but the protection scope disclosed in the present invention is not limited thereto. The protection scope disclosed in the present invention shall be based on the protection scope of the claims.

Claims

1. A method for controlling a treatment bed, characterized in that: The control method comprises the following steps: 1) The base coordinate system is constructed with the Gamma Knife six-dimensional treatment bed gantry rotation center as the origin. Then, the coordinate systems of each axis are established in sequence, and the positions and directions of XT, YT, and ZT relative to the coordinate system are defined. With the gantry rotation center as the origin, a right-handed system is used to construct the base space coordinate system. The X, Y, and Z spatial coordinates are established. Based on the X, Y, and Z coordinates, the Xt axis for rotation along the X axis, the Yt axis for rotation along the Y axis, and the Zt axis for rotation along the Z axis are established. 2) The Z-axis assembly of the Gamma Knife six-dimensional treatment bed is a double-layer lifting structure, which is divided into the Z1 axis and the Z2 axis. The middle lifting seat is fixed on the guide rail of the vertical support to form the Z1 axis that can be lifted and lowered. The XZ cross support plate is fixed on the guide rail of the middle lifting seat to form the Z2 axis that can be lifted and lowered. The world coordinates of the patient's lesion site are defined as P(x, y, z). The translational motion of position P on the Z axis is achieved by controlling the lifting motion of the Z1 axis and the Z2 axis respectively, which can be expressed as: [x′, y′, z′, 1] is the target position P(z)′, (tx, ty, tz) is the lifting displacement, where tx = 0, ty = 0; the displacement increment of the single-layer mechanism on the Z axis is expressed as: The double-layer lifting structure includes a base, a vertical support, a middle-layer lifting seat, a Z1-axis guide rail, a Z1-axis drive, a Z2-axis guide rail, a Z2-axis drive, and an XZ cross-support plate. The vertical support is arranged on the base, and the Z1-axis guide rail is vertically arranged on the vertical support. The middle-layer lifting seat is arranged on the Z1-axis guide rail through a first slider. The Z1-axis drive is arranged at the back of the middle-layer lifting seat and can drive the middle-layer lifting seat to move vertically on the vertical support. The Z2-axis guide rail is vertically arranged in front of the middle-layer lifting seat. The XZ cross-support plate is arranged on the Z2-axis guide rail through a second slider. The Z2-axis drive is arranged in front of the middle-layer lifting seat and can drive the XZ cross-support plate to move vertically on the middle-layer lifting seat. 3) The X-axis assembly of the Gamma Knife six-dimensional treatment bed includes an X-axis guide rail and a cantilever base. The cantilever base forms an X-axis that moves left and right along the X-axis guide rail on the XZ cross support plate. The patient's lesion position P moves in the positive and negative directions of the X-axis along the X-axis guide rail to the position P(x)′=(x′, y′, z′), which can be expressed as: Where (tx, ty, tz) is the translation amount, ty = 0, tz = 0; 4) The Gamma Knife six-dimensional treatment bed has a double-layer translation structure, including a Y-axis guide rail and a lower plate to form a Y-axis that can move back and forth. The upper and lower layers are installed between the two layers, and the middle is divided by a telescopic cavity to form the Y1 axis and the Y2 axis. When the lesion position P moves back and forth on the Y axis to the position P(y)′=(x′, y′, z′), its coordinates can be expressed as: Where tx = 0, tz = 0; the motion displacement of the single-layer translation structure Y1 and Y2 is expressed as: 5) The X-axis and Y-axis rotation components of the Gamma Knife six-dimensional treatment bed include a middle plate, a rotating component, a sliding component and a transmission component. The rotating component and the transmission component are installed between the lower plate and the middle plate; two transmission components and one rotating component form a three-point support structure. Each set of transmission components is connected to one set of sliding components. When the lead screw in the transmission component rotates, it drives the sliding component to move and then realizes the rotation of the middle plate around the X axis or around the Y axis. The lesion reference position P of the head body rotates in the positive direction around the X axis. The lead screw rotates by an angle of θ. The target reference position P to be rotated axz The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship: Rotate in the negative direction around the X axis, the screw rotates by an angle of θ, and the target reference position to be rotated is P axf The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship: The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions is expressed as: △x - =P axf -P Δx + =P axz -P The lesion reference position P of the head body rotates in the positive direction around the Y axis, and the screw rotates at an angle of θ. The target reference position P to be rotated ayz The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship: Rotate in the negative direction around the Y axis, the screw rotates by an angle of θ, and the target reference position to be rotated is P ayf The rotation vector T matrix of (x′, y′, z′) relative to the initial position P satisfies the following relationship: The displacement vector of the target reference position relative to the initial position after the screw rotates in the positive and negative directions around the Y axis is expressed as: △x - =P ayf -P △x + =P ayz -P 6) The Z-axis rotation assembly of the Gamma Knife six-dimensional treatment bed includes an upper plate and a Zt-axis transmission assembly, wherein the Zt-axis transmission assembly is installed between the middle plate and the upper plate. Driven by the Z-axis rotation assembly, the upper plate rotates around the Z axis along the circular guide rail; the upper plate rotates forward along the circular guide rail by an angle θ to the target position P azz (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship: Rotate in the negative direction by angle θ to the target position P azf (x′, y′, z′), the rotation vector relative to the initial reference position P satisfies the following relationship: The upper plate rotates around the Z axis in the positive and negative directions by an angle θ, and the displacement increment of the target position of the lesion reference position relative to the initial position is expressed as: △x - =P azf -P △x + =P azz -P。 2. The control method of the treatment bed according to claim 1, characterized in that: The X-axis assembly in step 3) includes an X-axis guide rail and an overhang seat. The X-axis guide rail is arranged horizontally in front of the XZ cross support plate. The overhang seat is arranged on the X-axis guide rail through a third slider. The X-axis drive is arranged in front of the XZ cross support plate and can drive the overhang seat to move horizontally on the XZ cross support plate.

3. The control method of the treatment bed according to claim 2, characterized in that: The double-layer translation structure in step 4) includes a Y-axis guide rail and a lower plate. The Y-axis guide rail is provided on the overhang seat. The lower plate is set on the Y-axis guide rail through a fourth slider. The Y-axis drive is set on the overhang seat and can drive the lower plate to move laterally along the Y-axis direction on the overhang seat.

4. The control method of the treatment bed according to claim 3, characterized in that: The X-axis and Y-axis rotation components in the step 5) include a middle plate, a rotating component, a sliding component and a transmission component, the sliding component and the rotating component are arranged between the middle plate and the lower plate, the sliding component is connected to the transmission component, the lower plate is arranged on the Y-axis guide rail through the fourth slider, the sliding component includes an inclined surface connection piece, a first guide rail, a second guide rail, a special-shaped connection piece, a self-aligning ball bearing, a first bearing seat, a bearing end cover, a locking nut and a third guide rail; the first guide rail is arranged on the lower plate, the inclined surface connection piece is arranged on the first guide rail and can slide along the first guide rail, the second guide rail is arranged on the inclined surface of the inclined surface connection piece, the special-shaped connection piece is arranged on the second guide rail and can slide along the second guide rail, the first bearing seat is arranged on the special-shaped connection piece, a self-aligning ball bearing is arranged in the first bearing seat, a bearing end cover is arranged above it, the bearing end cover is connected to the first bearing seat through a locking nut, a third guide rail is arranged above the bearing end cover, the middle plate is arranged The gear train is connected to the transmission mechanism by the second end of the gear train, and the gear train is connected to the transmission mechanism by the second end of the gear train.

5. The control method of the treatment bed according to claim 4, characterized in that: The Z-axis rotation assembly in the step 6) includes an upper plate and a Zt-axis transmission assembly, the Zt-axis transmission assembly is installed between the middle plate and the upper plate, the Zt-axis transmission assembly includes an arc guide rail and a Zt transmission, the Zt transmission includes a reducer, a servo motor component, a pinion component and a circular arc gear, the reducer passes through the middle plate, the input end of the reducer is installed with a servo motor component, the output shaft of the reducer is installed with a pinion component, the circular arc gear is fixedly installed below the upper plate and meshes with the pinion component, the arc guide rail includes an arc guide rail and a slide seat, the slide seat is arranged on the arc guide rail, the arc guide rail is arranged on the upper plate, and the slide seat is arranged on the middle plate.

6. The control method of the treatment bed according to claim 5, characterized in that: The sliding components are divided into two groups, which are symmetrically arranged on both sides of the lower plate. The transmission components are divided into two groups, which are respectively arranged on the inner sides of the two groups of sliding components. The rotating component also includes 4 locking nuts and 4 bearing end covers. The 4 locking nuts are respectively assembled on the 4 shaft ends of the cross shaft to lock the third bearing to the cross shaft. A bearing end cover is set on each third bearing seat.

7. The control method of the treatment bed according to claim 6, characterized in that: The circular arc guide rail is divided into four sections and distributed on the same circumference.

8. The control method of the treatment bed according to claim 7, characterized in that: The overhanging seat is a cavity-shaped part with an upper opening and a front end opening, and the inner bottom surface of the cavity has a horizontal plane.

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