Method for compensating load of medical imaging device

Abstract

The invention relates to a method (1) for compensating the load of a gantry of a medical imaging device (10), in particular of a computed tomography instrument, the medical imaging device (10) having a plurality of adjusting legs (12). The method (1) comprises the following steps: laying (2) at least one compensation plate (16) on the ground (14), positioning (4) at least one adjustment foot (12) on the at least one compensation plate (16), aligning (6) the medical imaging device (10) relative to the ground (14) by adjusting the height of at least one of the adjustment feet (12), the height adjustment being carried out by rotating the adjustment foot (12), and adjusting the height of the medical imaging device (10) relative to the ground (14) by rotating the adjustment foot (12). And adjusting (8) the at least one adjusting leg (12) on the at least one compensating plate (16) by applying a predetermined torque, the predetermined torque being sufficiently large such that a predetermined load on the at least one adjusting leg (12) is achieved during the adjustment (8).

Description

Field of the Invention

[0001] The present invention relates to a method for compensating the load of a medical imaging device. The present invention also relates to a system for supporting a medical imaging device. Background Art

[0002] Includes persons with male and female identities regardless of the grammatical gender of specific terms.

[0003] Medical imaging devices, such as computed tomography scanners with gantries, are typically positioned upright on the ground. Since the ground usually does not have optimal flatness or evenness, local high points and / or low points on the ground must be compensated for by adaptive leveling feet. By adapting the height of each leveling foot, the correct orientation of the gantry relative to a reference surface can be achieved. Due to the small residual imbalance and large mass of the gantry rotating at high speeds, unwanted self-vibration behavior of the medical imaging device may occur. The more evenly the installation forces are distributed onto the leveling feet involved in the support, the less pronounced the vibrations are. Especially in statically overdetermined supports, it is important to distribute the load evenly, because otherwise tilting of the device may occur.

[0004] In order to ensure an even distribution of the installation forces onto the leveling feet, the installation forces must be measured when installing the imaging device. However, this is technically complex or difficult to perform without changing the installation state, and is therefore usually not done. Summary of the Invention

[0005] The object of the present invention is to provide a method for supporting a medical imaging device, in particular a computed tomography scanner with a gantry, which improves the vibration behavior of the device during operation.

[0006] The present invention relates to a method for compensating the load of a gantry of a medical imaging device, in particular a computed tomography scanner, wherein the medical imaging device has a plurality of leveling feet. The method comprises the following steps. Laying at least one compensation plate on the ground, positioning at least one leveling foot on at least one compensation plate, adjusting the height of at least one leveling foot so as to orient, in particular level, the medical imaging device relative to the ground, and adjusting at least one leveling foot on at least one compensation plate by applying a predetermined torque, wherein the predetermined torque is large enough such that a predetermined load is achieved on at least one leveling foot during the adjustment.

[0007] In this way, locally different roughness values and local unevenness of the ground can be equalized by means of at least one compensation plate. For example, the adjusting feet have a pitch thread (Steiggewinde) by which the adjusting feet are screwed into the medical imaging device, so that the height of the medical imaging device can be adjusted. Due to the equalization of the ground roughness, a known and constant frictional behavior is generated between at least one adjusting foot and the compensation plate located below it. Therefore, the load on the adjusting foot can be inferred from the torque applied to the adjusting foot. Thus, the compensated load of at least one adjusting foot can be adjusted by means of a preset tightening torque of the adjusting foot.

[0008] In particular, the adjustment of a (single) adjusting foot is sufficient to compensate for the load distribution of the other adjusting feet and thus of the entire medical imaging device. In the case of a known geometry or mass distribution of the medical device, in particular, the seating forces (also referred to as loads) on the other adjusting feet can be calculated from the seating force on one adjusting foot. It is thus possible, when installing the medical imaging device, to distribute the load evenly or in a defined manner to the adjusting feet in a simple way, thereby reducing the vibration excitation caused by the rotating gantry with mass of the medical imaging device.

[0009] By means of the compensation plate, a ground with a defined roughness is provided under at least one adjusting foot. It is also conceivable that one or more compensation plates are arranged under a plurality of adjusting feet, in particular under all of the plurality of adjusting feet. Thus, the plurality of adjusting feet of the medical imaging device can be adjusted at different positions. The compensation plate is preferably non-deformable. Thereby, a surface that is as rigid as possible with a constant friction value can be provided. It is also conceivable that the compensation plate is two-piece. In other words, the compensation plate can have a lower side and an upper side, where the two sides are different from each other. The lower side can have a higher adaptability and / or softness with respect to the ground, while the upper side can have greater rigidity. Thereby, an adaptable and particularly flat compensation plate can be provided.

[0010] At least one of the two sides of the compensation plate, in particular the upper side of the compensation plate, can have a constant roughness value in at least some regions. In other words, at least one side can preferably have a uniform coefficient of friction in the middle of the surface. Thus, preferably the same frictional force can occur in the middle of the surface of the compensation plate, which is defined as the product of the normal force acting on the side and the coefficient of friction.

[0011] In addition, the lower side can be designed to be anti-slip. Thus, the lower side can adhere to the ground. The compensation plate can also be designed as an integral one, especially with the same characteristics on both sides. Therefore, the compensation plate can be advantageously manufactured, especially as an injection molded part. The compensation plate can be designed as a flat plate. In other words, the extension of the compensation plate in two spatial directions can be significantly greater than its extension in the third spatial direction orthogonal to them. The compensation plate can have, for example, dimensions between 5 cm and 30 cm, preferably a side length of 8 cm to 15 cm, and a thickness of 0.3 to 10 mm, preferably 1 mm to 2 mm.

[0012] The adjustment feet of the medical imaging device are height-adjustable, so that the device is adjustable in terms of its orientation. For this purpose, preferably, especially through a pitch thread, there is a thread pair between each adjustment foot of the medical imaging device. Through a plurality (for example, 3 to 6, especially 4 or 5) of adjustment feet, the load of the device can be distributed to multiple adjustment feet. The device is positioned on at least one compensation plate by at least one adjustment foot. This can suitably be the adjustment foot with the least load. When adjusting the adjustment foot, friction occurs within the thread pair and between the lower side of the adjustment foot and the ground or compensation plate located below it. The thread friction, especially the frictional force, between the adjustment foot and the medical imaging device is known, for example, obtained through testing. The frictional force between the lower side of the adjustment foot and the upper side of the compensation plate is also known, for example, obtained through testing. Now, a defined torque can be applied via a torque wrench, and the torque minus the friction results in a predetermined seating force at the adjusted adjustment foot. Thereby, a defined seating force distribution can be achieved, and thus a low-vibration seating of the gantry can be realized.

[0013] Since the frictional force, especially the resistance, occurring during adjustment is known and reproducible, a constant ratio between the torque generated when adjusting the adjustment foot on the compensation plate and the seating force on the adjustment foot is produced. The torque can be obtained experimentally before adjustment. In particular, the relationship between the torque and the seating force can be determined, where this relationship is related to a constant friction ratio. Therefore, the seating plate can fulfill the task of keeping the frictional behavior of at least one seating foot on its ground (compensation plate) constant.

[0014] According to an embodiment, at least one compensating plate can be arranged torsion-proof on the ground, in particular adhesively bonded and / or screwed to the ground. Additionally, the compensating plate can also have an adhesive surface on the underside. Furthermore, the compensating plate can have holes for receiving fastening devices, in particular screws for anchoring. Additionally or alternatively, the compensating plate can also be arranged on the ground in other ways and / or arranged on the ground by a combination of multiple fixing possibilities. Thus, the compensating plate may be immovable or non-displaceable after being installed on the ground, in particular position-fixed. Furthermore, the compensating plate can thus be loaded orthogonally to the surface normal of the ground with loads, in particular torques, without slipping, bending or splitting.

[0015] The compensating plate can be made of metal or plastic, for example. The compensating plate can have a coating with defined frictional properties, for example paint.

[0016] According to an alternative embodiment, the compensating plate can be designed as a coating on the ground, in particular a hardened liquid coating. The coating can be poured as a leveling layer onto the bottom and distributed evenly and hardened. Epoxy resin can be particularly suitable for this, as it can provide a uniform and smooth surface after hardening. A hardened rubber coating is also conceivable. The coating can offer the advantage that large areas of the ground can be leveled particularly effectively and provided with substantially the same roughness.

[0017] According to an embodiment, the compensating plate can reduce, in particular completely compensate for, the unevenness of the ground. At least the underside of the compensating plate can be designed as an adaptive surface. Thereby, local unevenness can be compensated by the compensating plate.

[0018] According to an embodiment, a medical imaging device can be statically overdetermined by means of a plurality of adjusting feet. The bottom of the device can be approximately regarded as a plane, which requires three support elements to be statically determined in space. The medical imaging device can include four or more adjusting feet, such that the medical imaging device is statically overdetermined. Thereby, the total load of the medical imaging device can be introduced particularly evenly into the ground.

[0019] According to an embodiment, at least one adjusting foot can have at least one plunger, wherein the plunger can include a pitch thread, and wherein the height adjustment of the adjusting foot can be achieved by the rotation of the pitch thread of the plunger in a complementary internal thread of the medical imaging device. The pitch thread of the plunger can have a metric thread, in particular other thread types can also be provided. The pitch thread is arranged at the end remote from the adjusting foot disk. The plunger can be designed for threaded connection with the internal thread of the medical imaging device. Since the internal thread of the medical imaging device can be designed to be complementary to the pitch thread of the plunger, complementary right-hand and left-hand threads can be provided.

[0020] Preferably, the load acting on the adjusting feet is at least substantially proportional to the torque required to adjust the rotation of the feet. In other words, the share of the load of the adjusting feet in the total load of the device increases with increasing torque, at which the height-adjustable adjusting feet are further rotated out from the bottom of the medical imaging device. Thus, by rotating the adjusting feet, the load applied to the adjusting bracket can be changed. In addition, the adjustment of the adjusting feet may cause a corresponding redistribution of the loads of the other adjusting feet of the device. Thus, a uniform load distribution can be achieved.

[0021] Preferably, the frictional behavior of the thread pairing between the pitch thread and the complementary internal thread is known. The friction value of the thread pairing can be determined by experimental testing. Thus, the relationship between the load acting in the displacement direction of the support element along the thread engagement and the torque by which the thread pairing twists relative to each other can be determined. This relationship can be linear. Since the friction value can be constant, an invariant relationship can be expected in repeated engagement of the thread pairing.

[0022] Preferably, the frictional behavior between the lower side of the adjusting foot and the underlying compensation plate is known. The lower side of the adjusting foot can be at least partially formed by the adjusting foot plate. The load to be applied when adjusting at least one adjusting foot is related to the torque by which at least one adjusting foot is twisted relative to the mounting plate. In order to achieve the torque values determined experimentally, the frictional behavior between the lower side of the adjusting foot and the underlying adjusting foot must in particular be invariant.

[0023] Preferably, the predetermined torque can be determined taking into account the known frictional behavior of the thread pairing and / or the frictional behavior between the lower side of the adjusting foot and the underlying compensation plate. This can provide the advantage that the torque determined experimentally for rotating at least one adjusting foot always results in a corresponding invariant load.

[0024] Preferably, the adjusting foot plate and the plunger of the adjusting foot can be connected to each other against relative rotation. Thereby, relative movement, especially rotation, just cannot occur between the two components of the adjusting foot. Thus, the accuracy of the method can be increased because the friction value between the mentioned components does not need to be considered. In addition, the plunger can be formed of a metallic material, especially steel, preferably tool steel. The plunger and the adjusting foot plate can be constructed integrally, especially of the same material.

[0025] Preferably, the adjusting feet can be designed as multi-piece, in particular having at least partial coating, and / or at least partially formed of a second material. The second material can include an elastomer, preferably rubber. In addition, the second material can be designed to be a friction fit that is particularly low-friction relative to at least one compensation plate. Thus, adjustment can be carried out with reduced force expenditure, in particular reduced torque. In particular, the adjusting foot plate of the adjusting foot is formed of the second material. It is also conceivable that the adjusting foot plate has a coating formed of the second material. In addition, the adjusting foot plate can be integrally constructed with the plunger and have an insert formed of the second material, which insert is installed, in particular glued or otherwise fixed, into the adjusting foot plate. In addition, the second material can be designed to be particularly vibration-absorbing, in particular flexible. Thus, the adjusting foot plate can suppress the periodic movement of the medical imaging device and in particular absorb vibrations.

[0026] Preferably, the friction value between the pitch thread and the internal thread can be reduced by means of a lubricant, in particular oil. By reducing the friction within the thread pair of a plurality of adjusting feet, the torque for adjusting at least one adjusting foot can be reduced.

[0027] Preferably, the adjusting foot can have a hole that extends along the plunger, in particular in the middle. The hole can be designed to accommodate a fixing device. Thereby, the adjusting foot can be anchored to the ground. Thus, the tolerance of the device to vibrations can be increased.

[0028] Preferably, the adjusting foot can have a manipulation surface, in particular a manipulation area, so that it can be rotated by means of a rotary tool, in particular a torque wrench. The manipulation surface can be arranged at the distal end of the plunger. By rotating the adjusting foot on the manipulation area, the adjusting foot rotates relative to the ground, in particular the compensation plate, and is forced to shift in the longitudinal direction, in particular out of the internal thread of the medical imaging device. The manipulation surface can be designed as an outer peripheral polygon and / or an internal hexagon, in particular a hexagon, so that the corresponding tool can thus engage therewith. The manipulation area can be located inside the medical imaging device and be accessible. Additionally or alternatively, the manipulation surface can be arranged on the outer periphery of the adjusting foot plate. Thus, the manipulation area can be accessed outside the medical imaging device.

[0029] The invention also relates to a system for supporting the gantry of a medical imaging device, in particular a computed tomography scanner. The system can include a plurality of adjusting feet designed to be screwed into the medical imaging device and at least one compensation plate that is arranged and / or can be arranged on the ground, wherein at least one adjusting foot is arranged and / or can be arranged on at least one compensation plate, and wherein at least one adjusting foot can be loaded with a specific torque relative to the medical imaging device, so as to produce a uniform load distribution of the medical imaging device onto the plurality of adjusting feet.

[0030] The system can in particular include three, four or five, and more if necessary, adjusting feet. Thereby, the medical imaging device can be statically overdeterminedly supported. The adjusting feet can be screwed into the medical imaging device in a height-adjustable manner by means of complementary thread pairs of each adjusting foot. A compensation plate can be positioned below at least one adjusting foot. Thus, a friction fit can be defined between at least one adjusting foot and its ground (compensation plate). In other words, there is a constant or repeatable frictional behavior between at least one mounting foot and the compensation plate. At least one adjusting foot can be loaded with a specific torque with respect to two friction fits: a) the thread pair and b) the friction between the adjusting foot and the compensation plate, whereby the load share of at least one adjusting foot can be changed, in particular increased. Compulsorily, the load shares of the other adjusting feet are also changed thereby, so that a compensated distribution of the load onto a plurality of adjusting feet of the medical imaging device can be achieved.

[0031] The invention also relates to a medical imaging device having a system according to the invention. Thus, for the medical imaging device, a load distribution can be achieved in the manner according to the invention. The invention also relates to a medical imaging device configured for placement in the case of using the method according to the invention.

[0032] The individual embodiments and the individual features can be combined with other embodiments and other features and thus form new embodiments. The designs and advantages of the embodiments and features similarly also apply to the new embodiments. In addition, the designs and advantages mentioned in connection with the medical imaging device similarly also apply to the method and vice versa. Description of the Drawings

[0033] Subsequently, the invention will be described with reference to the drawings according to embodiments. The illustrations in the drawings are schematic, very simplified, and not necessarily to scale. Among them:

[0034] Figure 1 A flowchart of a method for compensating the load of a medical imaging device is shown,

[0035] Figure 2 A fragment of a system for supporting a medical imaging device is shown, and

[0036] Figure 3 A top view of a system for supporting a medical imaging device is shown.

[0037] In the drawings, the same features are denoted by the same reference numerals. Detailed Description of the Invention

[0038] Figure 1Shows the flow of Method 1 in the sequence of respective steps. In the first step, a compensation plate 16 is laid on the ground 14. Thereby, a flat surface with a constant friction value is provided on the surface of the compensation plate 16, particularly on at least a part of the entire surface, through the compensation plate 16. In the second step, the adjustment feet 12 of the medical imaging device 10 are positioned on the compensation plate 16. The medical imaging device 10 includes a plurality of adjustment feet 12, particularly 3, 4, or 5 adjustment feet 12. Subsequently, by adjusting the height of at least one of the adjustment feet 12, the orientation of the medical imaging device 10 relative to the ground 14 can be carried out.

[0039] The adjustment feet 12 are designed to move into or out of the medical device when the adjustment feet 12 rotate relative to the medical imaging device 10. Thus, the distance between the adjustment foot plate 20 of the adjustment feet 12 and the medical imaging device can be changed. Therefore, the unevenness of the ground 14 can be compensated by the height-adjustable adjustment feet 12. The orientation can be checked and adjusted relative to different reference surfaces on the gantry (such as a fixed frame, a drum) in space. After the orientation, it may occur that due to the orientation of the center of gravity relative to the respective adjustment feet 12, the distribution of the installation forces on the individual adjustment feet 12 is uneven. Thereby, vibration excitation of the medical imaging device may occur during the rotation of the gantry with mass.

[0040] Therefore, at least one adjustment foot on at least one compensation plate is adjusted. In particular, it is sufficient to adjust only one of the plurality of adjustment feet 12, so that the load distribution of the entire medical imaging device 10 on all the loaded adjustment feet 12 can be compensated. Here, the adjustment feet 12 are loaded with a predetermined torque. In other words, the adjustment feet 12 rotate relative to the medical imaging device 10 with a predetermined torque, particularly by rotating the medical imaging device relative to the compensation plate 16. Due to the known friction behavior between one adjustment foot 12 and the compensation plate 16, and additionally due to the known friction behavior of the pitch thread 19 of the adjustment feet 12 and the thread pairing of the internal thread 22 of the medical imaging device 10, the load of one adjustment foot 12 can be adjusted with a predetermined torque. Thereby, the predetermined load of one adjustment foot 12 can be adjusted. In addition, thereby, in particular, the distribution of the other adjustment feet 12 is compensated, so as to optimize the vibration behavior of the medical imaging device 10.

[0041] Figure 2A fragment of a system for supporting a medical imaging device 10 is shown. A compensation plate 16 is arranged on the ground 14. The compensation plate 16 can be glued and / or screwed and / or otherwise placed on the ground 14 such that it cannot slide, compress or split relative to the ground 14. The adjusting feet 12 are positioned above the compensation plate 16 in the installed state. The adjusting feet include a plunger 18, and an adjusting foot disk 20 is arranged on the plunger such that the adjusting foot disk 20 contacts the compensation plate 16. The plunger 18 can include tool steel and is integrally formed with the adjusting foot disk 20, especially in one piece. The adjusting foot disk 20 can include an elastic material, preferably rubber, especially a second material. The adjusting foot disk 20 is especially coated with the second material. It is also conceivable that the adjusting foot disk 20 is formed of the second material, where the second material is different from the material of the adjusting foot 12. Thereby, an increase in the damping characteristics of the adjusting foot 12 can be achieved and at the same time an increase in the strength of the adjusting foot can be achieved. At the opposite distal end, the adjusting foot 12 has a manipulation surface 24, especially a manipulation area, which is designed to engage with a complementary tool, especially a torque wrench. Thus, the adjusting foot 12 is advantageously twisted relative to the medical imaging device 10. The medical imaging device 10 includes an internal thread for each adjusting foot 12, which is designed to be complementary to the pitch thread 19 constructed on the outer periphery of the plunger 18. Thus, the adjusting foot 12 can be screwed into the internal thread 22 of the medical imaging device 10. In addition, the plunger 18 can have a central hole extending along the longitudinal axis of the plunger. Thus, the entire adjusting foot 12 can be anchored to the ground 14 by a fixing device.

[0042] Figure 3 A top view of a system for supporting a medical imaging device 10 is shown. The Figure 3 The underside shown has four adjusting feet 12. Thus, the system is statically over-determined in terms of support. Thus, especially on the two diagonals shown, tilting may occur in the different loads of the individual adjusting feet 12. A compensation plate 16 is arranged between the ground 14 and one of the adjusting feet. The adjusting foot 12 positioned thereon can be twisted with a preset torque such that its load reaches a predetermined value. If the torque to be applied does not cause the adjusting foot 12 to rotate on the compensation plate 16, then the adjusting foot 12 must first be rotated into the medical imaging device 10 and then rotated out using the torque.

Claims

1. A method (1) for compensating for a load on a gantry of a medical imaging device (10), in particular a computed tomography device, wherein: The medical imaging device (10) has a plurality of adjustment feet (12), and the method comprises the following steps: - laying (2) at least one compensating plate (16) on the ground (14), - positioning (4) at least one adjustment foot (12) on the at least one compensation plate (16), - orienting (6) the medical imaging device (10) relative to the floor (14) by adjusting the height of at least one of the adjustment feet (12), wherein the height adjustment is achieved by rotating the adjustment foot (12), and - adjusting (8) the at least one adjustment foot (12) on the at least one compensation plate (16) by applying a predetermined torque, wherein the predetermined torque is sufficiently large to achieve a predetermined load on the at least one adjustment foot (12) during the adjustment (8).

2. The method according to claim 1, wherein: The compensating plate (16) is mounted on the floor (14) in a rotationally fixed manner, in particular is glued and / or screwed to the floor (14).

3. A method according to any one of the preceding claims, wherein: The compensating plate (16) is designed as a coating on the floor (14), in particular a hardening liquid coating.

4. A method according to any one of the preceding claims, wherein: The at least one adjustment foot (12) has at least one plunger (18), wherein the plunger (18) comprises a pitch thread (19), and wherein the height adjustment of the adjustment foot (12) is achieved by rotating the pitch thread (19) of the plunger (18) in a complementary internal thread (22) of the medical imaging device (10).

5. A method according to any one of the preceding claims, wherein: The load acting on the adjusting foot (12) is at least substantially proportional to the torque required for rotating the adjusting foot (12).

6. A method according to any one of the preceding claims, wherein: The friction behavior between the underside of the adjustment foot (12) and the compensation plate (16) located underneath is known.

7. A method according to any one of the preceding claims, wherein: The predetermined torque is determined taking into account the known friction behavior of the threaded pair and / or the friction behavior between the underside of the adjustment foot (12) and the compensating plate (16) located underneath.

8. A method according to any one of the preceding claims, wherein: The adjusting foot plate (20) and the plunger (18) of the adjusting foot (12) are connected to each other in a rotationally fixed manner.

9. A method according to any one of the preceding claims, wherein: The adjusting foot (12) is designed in multiple parts, in particular has an at least partial coating, and / or is at least partially formed from a second material.

10. A method according to any one of the preceding claims, wherein: The friction values ​​of the threaded pairing are reduced by means of a lubricant, in particular oil.

11. A method according to any one of the preceding claims, wherein: The adjusting foot has a hole which extends, in particular, centrally along the plunger.

12. A method according to any one of the preceding claims, wherein: The adjusting foot (12) has an actuating surface (24), in particular an actuating region, so that it can be turned using a turning tool, in particular a torque wrench.

13. A system for supporting a gantry of a medical imaging device (10), in particular a computed tomography device, comprising a plurality of adjustment feet (12) designed to be screwed into the medical imaging device (10) and at least one compensation plate (16) arranged and / or placeable on a floor (14), wherein: At least one of the adjustment feet (12) is arranged and / or can be arranged on the at least one compensation plate (16), wherein the at least one adjustment foot (12) can be loaded with a specific torque relative to the medical imaging device (10), thereby generating a uniform load distribution of the medical imaging device (10) to the plurality of adjustment feet (12).

14. A medical imaging device (10) having a system according to claim 13.

15. A medical imaging device (10) configured to be positioned when using the method (1) according to any one of claims 1 to 12.

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