Control method of lifting mechanism, lifting control device and medical scanning equipment

Abstract

The invention relates to a control method of a lifting mechanism, a lifting control device and medical scanning equipment. The lifting mechanism comprises a supporting assembly for supporting a load and a driving assembly for driving the supporting assembly to ascend and descend in the vertical direction, and the driving assembly comprises a driving motor and a driving part which is driven by the driving motor and moves in the horizontal direction. The method includes adjusting a current target vertical lift speed of the support assembly based on a desired horizontal movement speed of the drive portion and a ratio of a vertical lift speed of the support assembly at a current vertical height of the support assembly to a horizontal movement speed of the drive portion; and according to the adjusted current target vertical lifting speed, the driving motor drives the driving part to move in the horizontal direction at the corresponding horizontal moving speed. The lifting control device can realize the control method. The medical scanning equipment comprises the lifting control device.

Description

Technical Field

[0001] This invention generally relates to the medical field, and more specifically to a control method for a lifting mechanism, a lifting control device, and a medical scanning device. Background Technology

[0002] When medical scanning equipment scans an object, it typically requires lifting and lowering control of the object. Common lifting mechanisms, such as scissor lifts, convert horizontal movement into vertical movement to achieve lifting control. However, the relationship between this horizontal and vertical movement is not linear, which introduces many problems when controlling the lifting and lowering of the object.

[0003] If the lifting height is controlled by adjusting the horizontal movement distance of the scissor legs and then by adjusting its relationship with the vertical lifting height, the non-linear relationship between the horizontal and vertical movements, especially at certain heights where a small horizontal movement distance can result in a much larger change in vertical lifting height, would significantly reduce the accuracy of height control. This method also increases computational complexity and cost. Therefore, operators generally prefer to measure and control the vertical lifting height directly. However, to directly measure the vertical lifting height, the vertical lifting motion needs to be kept at a constant speed. But again, because the horizontal and vertical movements of the scissor legs are non-linear, the speed of the drive motor driving the horizontal movement will vary over a wide range and remain above its rated speed for extended periods. This increases noise, is detrimental to the drive, shortens the motor's lifespan, and reduces output torque.

[0004] Therefore, there is a great need for a new technology to control the lifting mechanism, which can overcome the problems caused by the nonlinearity between the horizontal and vertical movements and achieve better performance. Summary of the Invention

[0005] The present invention aims to overcome the above-mentioned and / or other problems in the prior art. The control method and lifting control device for the lifting mechanism provided by the present invention can achieve precise control of the lifting motion while keeping the rotational speed of the drive motor driving the horizontal movement very small and not exceeding the rated speed. The medical scanning device of the present invention, employing the above-mentioned control method and lifting control device, can achieve precise, stable, and efficient control of the lifting of the object to be scanned.

[0006] According to a first aspect of the present invention, a control method for a lifting mechanism is provided. The lifting mechanism may include a support assembly supporting a load and a drive assembly driving the support assembly to move vertically. The drive assembly may include a drive motor and a drive unit driven by the drive motor to move horizontally. The control method may include: adjusting a current target vertical movement speed of the support assembly based on a desired horizontal movement speed of the drive unit and a ratio of the vertical movement speed of the support assembly to the horizontal movement speed of the drive unit at the current vertical height of the support assembly; and, according to the adjusted current target vertical movement speed, causing the drive motor to drive the drive unit to move horizontally at a corresponding horizontal movement speed.

[0007] According to a second aspect of the invention, a lifting control device is also provided, which may include a lifting mechanism and a control unit. The lifting mechanism may include a support assembly and a drive assembly. The support assembly is used to support a load. The drive assembly is used to drive the support assembly to move vertically, and the drive assembly includes a drive motor and a drive unit driven by the drive motor to move horizontally. The control unit is configured to: adjust a current target vertical lifting speed of the support assembly based on a desired horizontal movement speed of the drive unit and a ratio of the vertical lifting speed of the support assembly to the horizontal movement speed of the drive unit at the current vertical height of the support assembly; and control the drive motor to drive the drive unit to move horizontally at a corresponding horizontal movement speed according to the adjusted current target vertical lifting speed.

[0008] This invention uniquely introduces a ratio between the vertical lifting speed of the support component and the horizontal movement speed of the drive unit at the current vertical height in the lifting control. Therefore, by simply detecting the current vertical height of the support component, the current target vertical lifting speed can be obtained using the corresponding ratio and the desired horizontal movement speed of the drive unit. The actual rotational speed of the drive motor used to drive the horizontal movement to achieve this target vertical lifting speed will not exceed the rated speed, and the variation is also very small.

[0009] The aforementioned current target vertical lifting speed can be specifically defined as: the product of the desired horizontal movement speed of the drive unit and the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at the current vertical height.

[0010] In this invention, the desired horizontal movement speed of the drive unit can be determined based on the entire rising or falling time of the desired support component and the range of the horizontal movement distance of the drive unit.

[0011] In this invention, the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at various vertical heights within the vertical lifting stroke range of the support component can be obtained through pre-testing, and the horizontal movement speed of the drive unit remains constant during the pre-testing.

[0012] During the pre-test, the vertical height of the support assembly can be measured by a load encoder, and the vertical lifting speed of the support assembly can be calculated based on the vertical height difference within a predetermined time interval.

[0013] During the pre-test, the encoder of the drive motor can measure the horizontal movement distance of the drive unit and calculate the horizontal movement speed of the drive unit based on the horizontal movement distance within a predetermined time interval.

[0014] In this invention, the vertical heights of the support components obtained during the pre-test and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit can be stored in the form of a lookup table.

[0015] In this invention, a ratio curve can be fitted based on the various vertical heights of the support component obtained during the test and the corresponding ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

[0016] The ratio curve can be represented by the following function: y = 9 * 10 -6 x 2 +5*10 -4 x+0.9327, R 2 =0.9939, where R 2 The goodness of fit is represented by x, which represents the vertical height of the support component, and y represents the ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

[0017] In this invention, the current target vertical lifting speed of the support component can be adjusted every predetermined time interval or predetermined vertical height interval.

[0018] According to a third aspect of the present invention, a medical scanning device is provided, which may include the lifting control device described above. This medical scanning device, through the lifting control device, can achieve precise and stable control over the lifting of the object to be scanned, and can also adjust the lifting speed according to clinical needs while shortening the total scanning time.

[0019] According to a fourth aspect of the present invention, a computer-readable storage medium is also provided having encoded instructions recorded thereon, which, when executed, enable the control method of the lifting mechanism of the present invention.

[0020] Other features and aspects of the invention will become clearer from the following detailed description taken in conjunction with the accompanying drawings. Attached Figure Description

[0021] The invention can be better understood by describing exemplary embodiments of the invention in conjunction with the accompanying drawings, in which:

[0022] Figure 1 This is a schematic diagram of a lifting mechanism according to an embodiment of the present invention;

[0023] Figure 2 A flowchart of a control method for a lifting mechanism according to an embodiment of the present invention;

[0024] Figure 3 The graphs showing the relationship between the drive motor speed and the load height in the lifting mechanism control methods of the present invention and the prior art are shown respectively.

[0025] Figure 4a and Figure 4b The vertical lifting speed of the support assembly and the rotational speed of the drive motor at various vertical heights within its vertical lifting stroke range, obtained during pre-testing according to embodiments of the present invention, are shown respectively.

[0026] Figure 5 An embodiment of the invention is shown, based on a ratio curve fitted according to the various vertical heights of the support components obtained during pre-testing and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit.

[0027] Figure 6 A schematic block diagram of a lifting control device according to an embodiment of the present invention is shown; and

[0028] Figure 7 A graph showing the relationship between drive motor speed and load height in the prior art is presented. Detailed Implementation

[0029] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention can obviously be implemented in many other ways different from those described herein. Those skilled in the art can make similar extensions and derivations based on actual application situations without departing from the spirit of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0030] Unless otherwise defined, the technical or scientific terms used in the claims and description shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in the description and claims of this application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the element or object preceding "comprising" or "including" encompasses the element or object listed following "comprising" or "including" and its equivalents, and do not exclude other elements or objects. The terms "connected" or "linked" and similar terms are not limited to physical or mechanical connections, nor are they limited to direct or indirect connections.

[0031] According to an embodiment of the present invention, a control method for a lifting mechanism is provided.

[0032] Figure 1 A schematic diagram of a lifting mechanism 100 according to an embodiment of the present invention is shown. Figure 1 As shown, the lifting mechanism 100 may include a support assembly 120 and a drive assembly 140. The support assembly 120 can support the load ( Figure 1 (Not shown in the image). The drive assembly 140 can drive the support assembly 120 in the vertical direction (…). Figure 1 The drive assembly 140 may include a drive motor 142 and a drive unit 144. The drive unit 144 can move horizontally (in the Z direction) under the drive of the drive motor 142. Figure 1 Move in the X direction (of the text).

[0033] As the drive unit 144 moves horizontally, the entire drive assembly 140 can drive the support assembly 120 to rise and fall vertically.

[0034] Figure 1 The lifting mechanism 100 is a scissor-type lifting mechanism, and its scissor legs 146 can be used as follows: Figure 1 The arrangement shown is on a pair of linear tracks, such that ends A and B can slide horizontally. The drive unit 144 can be, for example, end A, which can be fixed to the nut 148a in the lead screw and nut structure. The drive motor 142 drives the screw 148b in the lead screw and nut structure to rotate, and the relative rotation between the screw 148b and the nut 148a causes end A to move horizontally, thereby driving the scissor legs 146 to achieve vertical lifting of the support assembly 120.

[0035] Understandable, although Figure 1The scissor-type lifting mechanism is used as an example to introduce the lifting mechanism 100, but other types of lifting mechanisms can also be used, as long as the lifting mechanism also drives the vertical movement through the horizontal movement and the two are non-linear.

[0036] Figure 2 A control method 200 for a lifting mechanism according to an embodiment of the present invention is shown. For example... Figure 2 As shown, method 200 includes steps 220 and 240.

[0037] In step 220, the desired horizontal movement speed V of the drive unit 144 can be determined. 期望水平 And adjust the current target vertical lifting speed V of the support assembly 120 by the ratio Ratio of the vertical lifting speed of the support assembly 120 to the horizontal moving speed of the drive unit at the current vertical height H of the support assembly 120. 目标垂直 .

[0038] Next, in step 240, based on the adjusted current V... 目标垂直 The drive motor 142 drives the drive unit 144 to move at a corresponding horizontal speed V. 水平 Move horizontally.

[0039] As described above, since the lifting mechanism 100 achieves lifting control by converting the horizontal movement of the drive unit 144 into vertical movement in the vertical direction, when it is desired that the support assembly 120 moves at a certain vertical lifting speed V... 目标垂直 To achieve lifting and lowering, what is actually needed is to control the drive motor 142 to drive the drive unit 144 to reach a certain corresponding actual horizontal movement speed V. 实际水平 .

[0040] However, in existing technologies, to avoid problems such as poor lifting control accuracy, high computational cost, and great computational difficulty caused by the non-linearity between horizontal and vertical motion, the vertical lifting speed is kept as constant as possible. This allows the load encoder to directly measure the vertical height of the load and control its lifting. However, because the relationship between horizontal and vertical motion is non-linear, the horizontal movement speed must constantly change to maintain a constant vertical lifting speed, and correspondingly, the speed of the drive motor must also constantly change. Figure 7 As shown, the motor speed varies over a very wide range as the vertical height of the load changes, from 837 rpm to 3855 rpm. This wide speed range leads to greater noise and is detrimental to the performance of the drive system. Furthermore, from... Figure 7 As can be seen, the motor speed is above the rated speed for a long time, which will inevitably shorten the motor life and reduce the output torque.

[0041] Through extensive experiments and calculations, the inventors of this invention discovered that the relationship between the vertical height H of the support assembly 120 (i.e., the vertical height of the load) and the ratio of the vertical lifting speed of the support assembly 120 (i.e., the vertical lifting speed of the load) to the horizontal movement speed of the drive unit 144 follows a certain pattern. By obtaining this relationship between the vertical height H and the ratio in advance, the current vertical height H can be used to determine the appropriate load. 当前 The corresponding current ratio 当前 The desired horizontal moving speed V from the drive unit 144 期望水平 Calculate the target vertical lifting speed V of the current support component 120 by working backwards. 当前目标垂直 Support component 120, if at the current moment, uses this V... 当前目标垂直 If the lifting and lowering are performed, then the actual horizontal movement speed V of the drive unit 144 at the current moment is... 实际水平 In theory, it will be consistent with the expected V. 期望水平 The results are consistent; even considering actual errors, the difference between the two is very small. This allows for controlling the lifting and lowering of the support assembly 120 while simultaneously controlling the actual horizontal movement speed V of the drive unit 144. 实际水平 Maintaining a desired constant speed or close to a desired constant speed becomes possible, and correspondingly, the rotational speed of the drive motor 142 can vary within a very small range without exceeding its rated speed. This is because the current target vertical lifting speed V of the support assembly 120 must be considered. 当前目标垂直 The command drives the motor 142 to rotate at a corresponding speed, thereby driving the drive unit 144 to move horizontally at the desired speed V. 期望水平 Move, so the V can also be 当前目标垂直 This is called the current command vertical lift speed.

[0042] This invention provides a novel method for controlling a lifting mechanism, which enables the drive motor to rotate at or near its rated speed. Figure 3 The figures show graphs illustrating the relationship between the drive motor speed and the load height (vertical height of the support assembly) in the lifting mechanism control methods of the present invention and the prior art, respectively. Figure 3 As can be clearly seen, in the prior art, the motor speed varies continuously within a large range around the rated speed (3000 rpm) as the vertical height of the load changes. However, in this invention, regardless of the change in the vertical height of the load, the motor speed always remains at or slightly below the rated speed. This significantly reduces noise and improves the performance of the drive system, while also extending the motor's lifespan and increasing the output torque. Furthermore, the lifting mechanism control method of this invention can also shorten the total lifting stroke time of the lifting mechanism.

[0043] Optionally, the aforementioned current target vertical rise and fall speed V 当前目标垂直 The desired horizontal moving speed V of the drive unit 144 can be: 期望水平 Ratio, which is the ratio of the vertical lifting speed of the support assembly 120 to the horizontal moving speed of the drive unit at the current vertical height. 当前 The product of, i.e., V 当前目标垂直 =V 期望水平 Ratio 当前 .

[0044] Alternatively, the rise time T of the support component 120 can be used as a reference. 上升 Or the entire descent time T 下降 The desired horizontal speed V of the drive unit 144 is determined by measuring the horizontal movement distance S of the drive unit 144. 期望水平 For example, V 期望水平 =S / T 上升 , or V 期望水平 =S / T 下降 .

[0045] Optionally, the ratio Ratio of the vertical lifting speed of the support assembly 120 to the horizontal moving speed of the drive unit 144 at various vertical heights within its vertical lifting stroke range can be obtained through pre-testing, and the horizontal moving speed V of the drive unit 144 during the pre-testing period can be determined. 水平 Keep it constant.

[0046] Optionally, during the pre-test, the vertical height of the support assembly 120 can be measured by a load encoder, and the vertical lifting speed V of the support assembly can be calculated based on the vertical height difference within a predetermined time interval. 垂直 . Figure 4a The figure shows the vertical lifting speed V of the support assembly 120 at various vertical heights within its vertical lifting stroke range, obtained during pre-testing. 垂直 .

[0047] Optionally, during the pre-test, the horizontal movement distance of the drive unit 144 can be measured by the encoder of the drive motor 142, and the horizontal movement speed V of the drive unit 144 can be calculated based on the horizontal movement distance within a predetermined time interval. 水平 . Figure 4b The diagram shows the rotational speeds of the drive motor 142 at various vertical heights within the vertical lifting stroke range of the support assembly 120, obtained during pre-testing. Based on these rotational speeds, the horizontal movement speed V of the drive unit 144 at various vertical heights within the vertical lifting stroke range of the support assembly 120 can be calculated. 水平 .

[0048] Based on the vertical lifting speed V of the support assembly 120 at various vertical heights within its vertical lifting stroke range obtained during the pre-test, as described above... 垂直 and the horizontal moving speed V of the drive unit 144 水平 The ratio of the vertical lifting speed of the support assembly 120 to the horizontal moving speed of the drive unit 144 can be obtained at various vertical heights within its vertical lifting stroke range.

[0049] Optionally, the vertical heights H of the support assembly 120 obtained during the pre-test, along with the corresponding ratio of the vertical lifting speed of the support assembly 120 to the horizontal moving speed of the drive unit 144, can be stored in the form of a lookup table. When lifting control of the support assembly 120 is required, the value corresponding to the current vertical height H can be found from this lookup table. 当前 Corresponding speed ratio Ratio 当前 Alternatively, if no height value matching the current vertical height is found in the lookup table, the height value H closest to the current vertical height can be selected from the lookup table. 接近当前 Corresponding speed ratio 接近当前 Based on this speed ratio Ratio 当前 or Ratio 接近当前 And the desired horizontal movement speed V of the drive unit 144 期望水平 This allows us to obtain the target vertical lifting speed V of the support component 120 that is currently expected to be adjusted. 当前目标垂直 .

[0050] The above-mentioned lookup table method can already meet the accuracy requirements of lifting control. However, to further improve the accuracy of control, a ratio curve can be fitted based on the vertical heights H of the support component 120 obtained during the pre-test and the corresponding ratio of the vertical lifting speed of the support component 120 to the horizontal moving speed of the drive unit 144. Figure 5 As shown in the figure. Therefore, through this ratio curve, a corresponding speed ratio can be found for all vertical heights. When it is necessary to control the lifting of the support assembly 120, the speed ratio relative to the current vertical height H can be directly obtained from the ratio curve. 当前 Corresponding speed ratio Ratio 当前 Based on this speed ratio Ratio 当前 And the desired horizontal movement speed V of the drive unit 144 期望水平 This allows us to obtain the target vertical lifting speed V of the support component 120 that is currently expected to be adjusted. 当前目标垂直 .

[0051] Optionally, Figure 5 The ratio curve in the equation can be represented by, for example, the following function:

[0052] y = 9 * 10 -6 x 2 +5*10 -4 x+0.9327, R 2 =0.9939,

[0053] Among them, R 2 The goodness of fit is represented by x, which represents the vertical height of the support component 120, and y, which represents the ratio of the vertical lifting speed of the support component 120 to the horizontal moving speed of the drive unit 144.

[0054] It is understandable that for lifting mechanisms with identical specifications, the desired horizontal movement speed of the drive unit only needs to be determined once and can be directly used in every subsequent lifting control operation. Similarly, the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at various vertical heights only needs to be obtained through a single pre-test and can be directly used in every subsequent lifting control operation. Likewise, it is understandable that if the specifications of the lifting mechanism are already determined before it leaves the factory, the desired horizontal movement speed of the drive unit can be determined directly at this time, and the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at various vertical heights can be obtained through testing. Thus, when the user uses the lifting mechanism, they can directly adjust the target vertical lifting speed of the support component based on the desired horizontal movement speed of the drive unit provided by the manufacturer and the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at various vertical heights.

[0055] Optionally, the current target vertical lifting speed V of the support assembly 120 can be adjusted at predetermined time intervals or predetermined vertical height intervals. 当前目标垂直 The time interval and vertical height interval can be set according to specific lifting control requirements and scenarios.

[0056] According to embodiments of the present invention, a computer-readable storage medium is also provided, on which encoded instructions are recorded, which, when executed, implement the control method for the lifting mechanism of the present invention described above. The computer-readable storage medium may include hard disk drives, floppy disk drives, optical disc read / write (CD-R / W) drives, digital universal disk drives (DVD) drives, flash memory drives, and / or solid-state storage devices, etc.

[0057] According to an embodiment of the present invention, a lifting control device is also provided accordingly.

[0058] refer to Figure 6The illustration shows a lifting control device 600 according to the present invention, which includes a lifting mechanism 620 and a control unit 640.

[0059] The lifting mechanism 620 includes a support component 622 and a drive component 624. The support component 622 and the drive component 624 are the same as the support component 120 and the drive component 140 in the lifting mechanism 100 described above, and will not be described again here.

[0060] The control unit 640 is configured to: adjust the current target vertical movement speed of the support component 622 based on the desired horizontal movement speed of the drive unit and the ratio of the vertical movement speed of the support component to the horizontal movement speed of the drive unit at the current vertical height of the support component 622; and control the drive motor to drive the drive unit to move horizontally at a corresponding horizontal movement speed according to the adjusted current target vertical movement speed.

[0061] Optionally, the current target vertical lifting speed can be the product of the desired horizontal movement speed of the drive unit and the ratio of the vertical lifting speed of the support component 622 to the horizontal movement speed of the drive unit at the current vertical height.

[0062] Optionally, the control unit 640 may determine the desired horizontal movement speed of the drive unit based on the entire rise time or the entire fall time of the desired support component 622 and the range of the horizontal movement distance of the drive unit.

[0063] Optionally, the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at various vertical heights within the vertical lifting stroke range of the support component 622 can be obtained through pre-testing, and during the pre-testing, the control unit 640 controls the horizontal movement speed of the drive unit to remain constant.

[0064] Optionally, during the pre-test, the control unit 640 may control a load encoder to measure the vertical height of the support assembly 622 and calculate the vertical lifting speed of the support assembly 622 based on the vertical height difference over a predetermined time interval.

[0065] Optionally, during the pre-test, the control unit 640 may control the encoder of the drive motor to measure the horizontal movement distance of the drive unit and calculate the horizontal movement speed of the drive unit based on the horizontal movement distance within a predetermined time interval.

[0066] Optionally, the vertical heights of the support component 622 obtained during the pre-test and the corresponding ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit can be stored in the form of a lookup table.

[0067] Optionally, a ratio curve can be fitted based on the various vertical heights of the support component 622 obtained during the test and the corresponding ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

[0068] Optionally, the ratio curve is represented by the following function:

[0069] y = 9 * 10 -6 x 2 +5*10 -4 x+0.9327, R 2 =0.9939,

[0070] Among them, R 2 The goodness of fit is represented by x, which represents each vertical height of the support component 622, and y represents the ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

[0071] Optionally, the control unit 640 may adjust the current target vertical lifting speed of the support assembly 622 at predetermined time intervals or predetermined vertical height intervals.

[0072] The lifting control device of the present invention solves many problems caused by the nonlinearity between horizontal and lifting motion in the prior art without any additional hardware costs. The lifting control device of the present invention can implement the control method of the lifting mechanism according to the present invention as described above. Many design concepts and details applicable to the control method of the lifting mechanism of the present invention are also applicable to the lifting control device and can achieve the same beneficial technical effects, and will not be repeated here.

[0073] According to embodiments of the present invention, a medical scanning device is also provided, which may include the lifting control device according to the present invention as described above. The medical scanning device may be at least one of a CT (Computed Tomography) device, an NM (Nuclear Medicine) imaging device, and a PET (Positron Emission Tomography) device. The scanning bed of the medical scanning device can be mounted on the support assembly of the lifting mechanism, thereby achieving precise and stable control of the lifting of the scanning bed and the object to be scanned on the scanning bed by controlling the lifting of the support assembly as described above.

[0074] Specifically, when outside the scanning gantry aperture, unlike existing medical scanning beds which move up and down at a constant speed, the scanning bed in the medical scanning device of this invention can move up and down at a faster speed. However, inside the scanning gantry aperture, the scanning bed in the medical scanning device of this invention can move up and down at a slower speed than the constant speed of existing medical scanning beds. This better meets the needs of clinical operators while still shortening the total travel time of the scanning bed, allowing for faster positioning of the object to be scanned. For example, in a CT scanner, the total travel time of the scanning bed can be reduced from 15.4 seconds to 13.3 seconds.

[0075] The various aspects of the present invention have been described above through exemplary embodiments. However, it should be understood that various modifications can be made to the above exemplary embodiments without departing from the spirit and scope of the invention. For example, if suitable results can be achieved if the described techniques are performed in a different order and / or if components in the described system, architecture, device, or circuit are combined in different ways and / or replaced or supplemented by other components or their equivalents, then correspondingly, these modified other embodiments also fall within the scope of protection of the claims.

Claims

1. A control method for a lifting mechanism, the lifting mechanism comprising a support assembly supporting a load and a drive assembly driving the support assembly to move vertically, the drive assembly comprising a drive motor and a drive unit driven by the drive motor to move horizontally, the method comprising: The current target vertical lifting speed of the support assembly is adjusted based on the desired horizontal moving speed of the drive unit and the ratio of the vertical lifting speed of the support assembly to the horizontal moving speed of the drive unit at the current vertical height of the support assembly. as well as Based on the adjusted current target vertical lifting speed, the drive motor drives the drive unit to move horizontally at a corresponding horizontal moving speed.

2. The control method as described in claim 1, characterized in that, The current target vertical lifting speed is the product of the desired horizontal movement speed of the drive unit and the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at the current vertical height.

3. The control method as described in claim 1, characterized in that, The desired horizontal movement speed of the drive unit is determined based on the entire rise time or the entire fall time of the desired support component and the range of the horizontal movement distance of the drive unit.

4. The control method as described in claim 1, characterized in that, The ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit is obtained through pre-testing at various vertical heights within the vertical lifting stroke range of the support component, and the horizontal movement speed of the drive unit remains constant during the pre-testing.

5. The control method as described in claim 4, characterized in that, During the pre-test, the vertical height of the support assembly is measured by a load encoder, and the vertical lifting speed of the support assembly is calculated based on the vertical height difference within a predetermined time interval.

6. The control method as described in claim 4, characterized in that, During the pre-test, the encoder of the drive motor measures the horizontal movement distance of the drive unit and calculates the horizontal movement speed of the drive unit based on the horizontal movement distance within a predetermined time interval.

7. The control method according to any one of claims 4-6, characterized in that, The vertical heights of the support components obtained during the pre-test, and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit, are stored in the form of a lookup table.

8. The control method according to any one of claims 4-6, characterized in that, Based on the vertical heights of the support components obtained during the test and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit, a ratio curve is fitted.

9. The control method as described in claim 8, characterized in that, The ratio curve is represented by the following function: y = 9 * 10 -6 x 2 +5*10 -4 x+0.9327, R 2 =0.9939, where R 2 The goodness of fit is represented by x, which represents the vertical height of the support component, and y represents the ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

10. The control method according to any one of claims 1-4, characterized in that, The current target vertical lifting speed of the support assembly is adjusted at predetermined time intervals or predetermined vertical height intervals.

11. A lifting control device, comprising: The lifting mechanism includes: Support components, used to support loads; and A drive assembly for driving the support assembly to move vertically, the drive assembly including a drive motor and a drive unit driven by the drive motor and moving horizontally; and The control unit is configured as follows: Based on the desired horizontal movement speed of the drive unit and the ratio of the vertical lifting speed of the support assembly to the horizontal movement speed of the drive unit at the current vertical height of the support assembly, the current target vertical lifting speed of the support assembly is adjusted; and Based on the adjusted current target vertical lifting speed, the drive motor is controlled to drive the drive unit to move horizontally at a corresponding horizontal moving speed.

12. The lifting control device as described in claim 11, characterized in that, The current target vertical lifting speed is the product of the desired horizontal movement speed of the drive unit and the ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit at the current vertical height.

13. The lifting control device as described in claim 11, characterized in that, The control unit determines the desired horizontal movement speed of the drive unit based on the desired total rise time or total fall time of the support assembly and the range of horizontal movement distance of the drive unit.

14. The lifting control device as described in claim 11, characterized in that, The ratio of the vertical lifting speed of the support component to the horizontal movement speed of the drive unit is obtained through pre-testing at various vertical heights within the vertical lifting stroke range of the support component, and the control unit controls the horizontal movement speed of the drive unit to remain constant during the pre-testing.

15. The lifting control device as described in claim 14, characterized in that, During the pre-test, the control unit controls the load encoder to measure the vertical height of the support assembly and calculates the vertical lifting speed of the support assembly based on the vertical height difference within a predetermined time interval.

16. The lifting control device as described in claim 14, characterized in that, During the pre-test, the control unit controls the encoder of the drive motor to measure the horizontal movement distance of the drive unit and calculates the horizontal movement speed of the drive unit based on the horizontal movement distance within a predetermined time interval.

17. The lifting control device as described in any one of claims 14-16, characterized in that, The vertical heights of the support components obtained during the pre-test, and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit, are stored in the form of a lookup table.

18. The lifting control device as described in any one of claims 14-16, characterized in that, Based on the vertical heights of the support components obtained during the test and the corresponding ratio of the vertical lifting speed of the support components to the horizontal moving speed of the drive unit, a ratio curve is fitted.

19. The lifting control device as described in claim 18, characterized in that, The ratio curve is represented by the following function: y = 9 * 10 -6 x 2 +5*10 -4 x+0.9327, R 2 =0.9939, where R 2 The goodness of fit is represented by x, which represents the vertical height of the support component, and y represents the ratio of the vertical lifting speed of the support component to the horizontal moving speed of the drive unit.

20. The lifting control device as described in any one of claims 11-14, characterized in that, The control unit adjusts the current target vertical lifting speed of the support assembly at predetermined time intervals or predetermined vertical height intervals.

21. A medical scanning device, comprising a lifting control device as described in any one of claims 11-20.

22. A computer-readable storage medium having encoded instructions recorded thereon, which, when executed, implement the control method as described in any one of claims 1-10.

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