Collimator and X-ray apparatus

Abstract

The utility model discloses a collimator and an X-ray device. The collimator comprises a shell, a lead screw, a lead screw nut and an optical path part, and further comprises a first bearing seat, a second bearing seat, a first optical path, a second optical path, a third optical path, a fourth optical path, a fifth optical path and a sixth optical path, the first bearing seat is provided with a first surface facing the lead screw nut, the second bearing seat is provided with a fourth surface facing the lead screw nut, the lead screw nut is provided with a third surface facing the second bearing seat, and the first bearing seat and the second bearing seat are fixed in the shell and located at the two ends of the lead screw respectively; the screw rod can drive the screw rod nut to reciprocate between the first bearing seat and the second bearing seat; the first surface is parallel to the second surface, or the third surface is parallel to the fourth surface. The embodiment of the utility model provides an accurate and cost-effective solution which is suitable for an X-ray radiation environment and simplifies the traditional linear motion.

Description

[0001] Nouns and pronouns relating to persons in this patent application are not limited to a specific gender. Technical Field

[0002] The utility model relates to a collimator. Background Art

[0003] Collimators can be used in a variety of X-ray equipment. The collimator in the CT system is a component on the X-ray optical path, which is used to accurately position different scanning layer thicknesses, compensate for various deviations in the optical path, and improve the image quality of the patient scan and reduce the X-ray dose received by the patient through various filters.

[0004] In the common collimator drive structure design, the stepper motor and the lead screw are connected by a coupling, and the lead screw is supported by bearing seats at both ends. A zero position sensor is installed on the mechanical limit side of the motion mechanism. In order to accurately position and scan, the optical path components of the collimator need to be moved to the scanning center position. The incremental encoder is used to monitor the step loss caused by the linear motion of the lead screw driven by the stepper motor.

[0005] The existing application solutions for position control of collimator motion mechanism are mainly as follows:

[0006] Micro switch: obtains the limit position signal through mechanical collision, has very poor repetition accuracy, is easy to wear, has many parts, occupies a large space, and is difficult to install;

[0007] Hall or proximity sensors: require a moving mechanism to install magnetic components, and high-precision Hall or proximity sensors are expensive;

[0008] Optocoupler: sensitive to X-rays and prone to failure.

[0009] In addition, the existing collimator motion mechanism is often an isolated and redundant structure, which leads to expensive costs, cumulative assembly errors, and motion accuracy. For example, independent bearing support seats are set at both ends of the screw, and the support seats require special support parts. A coupling is used to connect the screw and the stepper motor assembly, and the stepper motor assembly also requires corresponding support parts. Extra shielding protection parts need to be set around X-ray sensitive parts.

[0010] Chinese utility model patent CN 216962477 U discloses a device for accommodating an optical path component and a computer tomography device, wherein the optical path component is used for X-ray radiation. The device comprises: a housing; a screw, which is rotatably supported relative to the housing around the main shaft rotation axis; a linear guide; a slide system, which is used to accommodate the optical path component, and the slide system is movably supported relative to the housing in parallel to the main shaft rotation axis by means of the linear guide; a threaded drive, which is used to convert the rotational motion of the screw around the main shaft rotation axis into the translational motion of the slide system parallel to the main shaft rotation axis and relative to the housing; a motor for driving the screw to perform rotational motion, wherein the housing has a first housing side extending in a plane on a first side plane, the first side plane is perpendicular to the main shaft rotation axis and is located between the motor and the slide system with respect to the main shaft rotation axis, and the first housing side is used to shield the motor to prevent scattering of X-ray radiation from the area of ​​the slide system and directed toward the motor. Utility Model Content

[0011] In view of this, the utility model proposes a collimator and an X-ray device.

[0012] According to a first aspect of the utility model, a collimator is provided, comprising a housing, a lead screw, a lead screw nut, and optical path parts, and also comprising: a first bearing seat, which has a first surface facing the lead screw nut, and the lead screw nut has a second surface facing the first bearing seat; a second bearing seat, which has a fourth surface facing the lead screw nut, and the lead screw nut has a third surface facing the second bearing seat, the first bearing seat and the second bearing seat are fixed in the housing and are separated at both ends of the lead screw, and the lead screw can drive the lead screw nut to reciprocate between the first bearing seat and the second bearing seat; the first surface is parallel to the second surface, or the third surface is parallel to the fourth surface.

[0013] In one embodiment, the second bearing seat includes a collision block, the collision block is fixed in the housing, and the fourth surface is on the collision block.

[0014] In one embodiment, the first bearing seat includes a collision block, the collision block is fixed in the housing, and the first surface is on the collision block.

[0015] In one embodiment, the collimator further comprises a coupling, wherein the coupling connects the stepping motor and one end of the lead screw.

[0016] In one embodiment, the collimator further comprises a first linear guide rail, wherein the first linear guide rail is parallel to the rotation axis of the lead screw, and the optical path component and the lead screw nut can move in a direction determined by the first linear guide rail and the lead screw.

[0017] In one embodiment, the collimator further comprises a second linear guide rail, and the lead screw nut can slide on the second linear guide rail.

[0018] In one embodiment, the optical path component is a collimating plate, a curved collimating tile, a plate-shaped energy spectrum filter or a wedge-shaped filter.

[0019] According to a second aspect of the utility model, an X-ray device is provided, comprising an X-ray tube, a stepper motor assembly, and a control unit, wherein the stepper motor assembly comprises a stepper motor and an incremental encoder, and also comprises a collimator as described above, wherein the stepper motor can drive the lead screw to rotate, and the control unit detects a collision of the lead screw nut and controls the movement of the stepper motor accordingly.

[0020] In one embodiment, the X-ray device is an X-ray machine or a CT machine.

[0021] Embodiments of the present utility model provide an accurate and cost-effective solution suitable for X-ray radiation environments and simplifying traditional linear motion. Through the lead screw and linear guide rail, the conversion from rotation to linear is achieved, so that belts, pulleys, racks, gears, sensors and radiation shielding components can be eliminated. The present utility model can completely eliminate the reference position sensor, and instead use mechanical limit collision combined with the index signal of the incremental encoder to determine the motion position control of the collimator optical path zero position. The stepper motor assembly can provide angle control and out-of-step monitoring. X-ray sensitive electronic components such as stepper motors and incremental encoders are placed outside the shielding cavity, and the entire frame provides positioning support for the motion mechanism, mechanical collision surfaces at the extreme positions, and necessary X-ray protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, so that those skilled in the art will be more aware of the above and other features and advantages of the present invention. In the accompanying drawings:

[0023] Figure 1 It is a schematic diagram of a shell of a collimator according to an embodiment of the utility model.

[0024] Figure 2 It is a schematic top view of a collimator according to an embodiment of the present utility model.

[0025] Figure 3 The collimator according to the embodiment of the present utility model is Figure 2 A schematic cross-sectional view in the vertical direction.

[0026] Figure 4 The collimator according to the embodiment of the present utility model is Figure 2 A schematic cross-sectional view in the horizontal direction.

[0027] Figure 5 FIG. 4 is a schematic top view of a collimator according to another embodiment of the present invention.

[0028] Figure 6 for Figure 5 Schematic diagram of the collision block of the collimator.

[0029] In the above drawings, the reference numerals used are as follows:

[0030] 100 collimator 120 second bearing seat

[0031] 102 housing 121 second surface

[0032] 104 bottom 122 screw

[0033] 106 groove 123 third surface

[0034] 108 first wall 124 screw nut

[0035] 110 second wall 125 fourth surface

[0036] 111 Stepper Motor Assembly 126 Optical Path Parts

[0037] 112 Stepper Motor 128 Alignment Slit

[0038] 114 Incremental encoder 130 First linear guide

[0039] 116 Coupling 132 Second linear guide

[0040] 118 first bearing seat 134 slider

[0041] 119 First Surface DETAILED DESCRIPTION

[0042] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with reference to the following embodiments.

[0043] Figure 1 FIG. 1 is a schematic diagram of a housing 102 of a collimator 100 according to an embodiment of the present invention. The housing 102 is used to carry some components of the collimator 100 and isolate the X-rays passing therethrough from the outside. Figure 1 As shown, the housing 102 has a bottom 104, and the bottom 104 has a slot 106 for X-rays to pass through. Figure 2 FIG. 1 is a schematic top view of a collimator 100 according to an embodiment of the present invention. Figure 3 The collimator 100 according to the embodiment of the present invention is Figure 2 A schematic cross-sectional view in the vertical direction. Figure 4 The collimator 100 according to the embodiment of the present invention is Figure 2 A schematic cross-sectional view of the horizontal direction of the Figures 2 to 4 As shown, the collimator 100 includes a housing 102, a lead screw 122, a lead screw nut 124, an optical path part 126, a first bearing seat 118, and a second bearing seat 120. The housing 102 has a first wall 108 and a second wall 110 opposite thereto. The collimator 100 can be used in X-ray equipment such as an X-ray machine, a CT machine, etc. The X-ray equipment includes an X-ray tube (not shown), a stepper motor assembly 111, a control unit (not shown), and a collimator 100. In this embodiment, the optical path part 126 is a collimation plate. In other embodiments, the optical path part 126 can be a curved collimation tile, a plate-shaped energy spectrum filter, a wedge filter, etc. The stepper motor assembly 111 includes a stepper motor 112 and an incremental encoder 114, and the stepper motor 112 can drive the lead screw 122 to rotate. The control unit detects the collision of the lead screw nut 124 and controls the movement of the stepper motor 112 accordingly.

[0044] like Figure 2 As shown, the optical path component 126 has a collimation slit 128, and the collimator 100 may also include a coupling 116, which connects the stepper motor 112 and one end of the lead screw 122. The optical path component 126 and other optical path functional components are fixed on the lead screw nut 124, and realize the functions of constraining the X-ray beam, filtering low-energy X-rays, filtering energy spectrum, and focusing offset compensation through single linear motion or combined motion. The optical path functional components may include the optical path component 126 and an arc plate beam constrainer, an arc X-ray beam filter, and a sheet X-ray beam filter.

[0045] like Figure 2 As shown, the collimator 100 may further include a first linear guide 130, the first linear guide 130 is parallel to the rotation axis of the lead screw 122, and the optical path component 126 and the lead screw nut 124 can move in the direction determined by the first linear guide 130 and the lead screw 122. Preferably, as Figure 3 and 4 As shown, the collimator 100 may further include a second linear guide rail 132, and the lead screw nut 124 can slide on the second linear guide rail 132. Figure 3 As shown, the screw nut 124 has a slider 134 that cooperates with the second linear guide rail 132. Figure 4 As shown, the slider 131 can cooperate with the first linear guide rail 130. If necessary, a supporting component 131 can be added under the optical path component 126. Figure 4 As shown, the second linear guide rail 132 may be disposed directly below the screw rod 122 to ensure the positioning accuracy of converting the rotational motion of the screw rod 122 into the linear motion of the screw nut 124 .

[0046] like Figure 3 As shown, the first bearing seat 118 has a first surface 119 facing the screw nut 124, and the screw nut 124 has a second surface 121 facing the first bearing seat 118. The second bearing seat 120 has a fourth surface 125 facing the screw nut 124, and the screw nut 124 has a third surface 123 facing the second bearing seat 120. The first bearing seat 118 and the second bearing seat 120 are fixed in the housing 102 and are separated at both ends of the screw 122. The stepper motor 112 drives the screw 122 to rotate, and the screw 122 can drive the screw nut 124 to reciprocate between the first bearing seat 118 and the second bearing seat 120.

[0047] The first surface 119 is parallel to the second surface 121, and / or the third surface 123 is parallel to the fourth surface 125. The first surface 119, the second surface 121, the third surface 123 and the fourth surface 125 are collision surfaces where the screw nut 124 collides with the first bearing seat 118 and the second bearing seat 120. Generally, such collision should be low momentum.

[0048] like Figure 3 As shown, a mechanical limit reference point can generally be found, and the repeatability of the stop position interval d1 only needs to meet a certain amount, and then the stepper motor 112 moves in the opposite direction. Usually, the index signal of the incremental encoder 114 outputs one pulse per rotation. The control unit only needs to find the first index signal after the direction is changed, and use its edge as the unique identification feature, which can be used as the zero point of the control unit. The micron-level repeatability of d2 can fully meet the system's requirements for the movement of the optical path component 126. The following matters need to be noted in the design:

[0049] The selection of collision surface should take into account its strength and rigidity to ensure fatigue resistance and reliability of collision motion during the life cycle;

[0050] The momentum during the collision can be reduced by reducing the running speed of the screw nut 124, the input current and the output torque of the stepper motor 112 during the collision.

[0051] The coupling 116 can be locked so that the first index of the incremental encoder 114 of the stepper motor assembly 111 is approximately 1 / 2 of the lead screw pitch away from the collision surface.

[0052] Figure 5 FIG. 1 is a schematic top view of a collimator 100 according to another embodiment of the present invention. Figure 5 As shown, in this embodiment, the second bearing seat 120 includes a collision block 136 , the collision block 136 is fixed in the housing 102 , and the fourth surface 125 is on the collision block 136 . Figure 6 for Figure 5Schematic diagram of the collision block 136 of the collimator 100. Figure 6 As shown, the collision block 136 has a mounting hole 138 and a slot 140, wherein the mounting hole 138 is used to fix the collision block 136 in the housing 102, and the slot 140 is for the screw rod 122 to pass through. In other embodiments, the first bearing seat 118 may include a collision block 136, the collision block 136 is fixed in the housing 102, and the first surface 119 is on the collision block 136.

[0053] Embodiments of the present utility model provide an accurate and cost-effective solution suitable for X-ray radiation environments and simplifying traditional linear motion. Through the lead screw and linear guide rail, the conversion from rotation to linear is achieved, so that belts, pulleys, racks, gears, sensors and radiation shielding components can be eliminated. The present utility model can completely eliminate the reference position sensor, and instead use mechanical limit collision combined with the index signal of the incremental encoder to determine the motion position control of the collimator optical path zero position. The stepper motor assembly can provide angle control and out-of-step monitoring. X-ray sensitive electronic components such as stepper motors and incremental encoders are placed outside the shielding cavity, and the entire frame provides positioning support for the motion mechanism, mechanical collision surfaces at the extreme positions, and necessary X-ray protection.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A collimator (100), comprising a housing (102), a lead screw (122), a lead screw nut (124), and an optical path component (126), wherein: include: A first bearing seat (118) having a first surface (119) facing the screw nut (124), and the screw nut (124) having a second surface (121) facing the first bearing seat (118); A second bearing seat (120) having a fourth surface (125) facing the screw nut (124); the screw nut (124) having a third surface (123) facing the second bearing seat (120); the first bearing seat (118) and the second bearing seat (120) are fixed in the housing (102) and are located at two ends of the screw (122); the screw (122) can drive the screw nut (124) to reciprocate between the first bearing seat (118) and the second bearing seat (120); The first surface (119) is parallel to the second surface (121), or the third surface (123) is parallel to the fourth surface (125).

2. The collimator (100) according to claim 1, characterized in that: The second bearing seat (120) comprises a collision block (136), the collision block (136) is fixed in the housing (102), and the fourth surface (125) is on the collision block (136).

3. The collimator (100) according to claim 1, characterized in that: The first bearing seat (118) includes a collision block (136), the collision block (136) is fixed in the housing (102), and the first surface (119) is on the collision block (136).

4. The collimator (100) according to claim 1, characterized in that: It also includes a coupling (116), wherein the coupling (116) connects the stepping motor (112) and one end of the lead screw (122).

5. The collimator (100) according to claim 1, characterized in that: It also includes a first linear guide rail (130), which is parallel to the rotation axis of the lead screw (122), and the optical path component (126) and the lead screw nut (124) can move in the direction determined by the first linear guide rail (130) and the lead screw (122).

6. The collimator (100) according to claim 1, characterized in that: It also includes a second linear guide rail (132), and the lead screw nut (124) can slide on the second linear guide rail (132).

7. The collimator (100) according to claim 1, characterized in that: The optical path component (126) is a collimating plate, a curved collimating tile, a plate-shaped energy spectrum filter or a wedge-shaped filter.

8. An X-ray device, comprising an X-ray tube, a stepper motor assembly (111), and a control unit, wherein the stepper motor assembly (111) comprises a stepper motor (112) and an incremental encoder (114), wherein: It also comprises a collimator (100) as claimed in any one of claims 1 to 7, wherein the stepper motor (112) can drive the lead screw (122) to rotate, and the control unit detects the collision of the lead screw nut (124) and controls the movement of the stepper motor (112) accordingly.

9. The X-ray device according to claim 8, characterized in that: The X-ray device is an X-ray machine or a CT machine.

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