Multi-point force measurement device and method for knee joint measurement spacers

Abstract

The application relates to the technical field of knee joint measuring spacer testing, and provides a multi-point force measuring device and method for a knee joint measuring spacer, the testing device comprising a fixed frame, an integral mechanical structure and a stacked plate structure, the upper shell of the knee joint measuring spacer is fixed between the narrow space between the upper end fixed plate and the stacked plate structure by using the testing device, the force value of the multiple measuring points of the soft upper shell is measured in the small space, the pressure loss value of the corresponding testing point is obtained, the measuring accuracy of the measuring spacer after being implanted into the knee joint is ensured through corresponding pressure loss compensation, the unqualified measuring spacer is returned to work or marked as a defective product in advance, the measuring error caused by the repeated installation of the measuring spacer with low measuring accuracy is avoided, and therefore the production, installation and measuring efficiency and accuracy of the measuring spacer are improved.

Description

Technical Field

[0001] This invention relates to the field of knee joint measuring pad shell testing technology, and in particular to a multi-point force measuring device and method for knee joint measuring pads. Background Technology

[0002] In knee surgeries, such as total knee replacement and knee repair surgery, accurate measurement of the internal pressure of the knee joint is crucial to the success of the surgery and the patient's postoperative rehabilitation. Therefore, knee pressure measuring pads have been developed and are widely used in the field of knee surgery.

[0003] During knee joint pressure measurement, the test pad needs to be in close contact with and fixed to the knee joint to accurately obtain pressure data. Therefore, the test pad needs to undergo relevant tests before leaving the factory, especially multi-point force transmission tests on soft materials in confined spaces, to avoid the product failing to obtain relevant data accurately, thus affecting the implantation effect. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-point force measurement device and method for knee joint measuring pads, so as to solve the problem of multi-point force transmission testing of soft materials in confined spaces, and to detect the differences in force transmission of sensor components concentrated in confined spaces, so as to better complete sensor calibration and improve sensor accuracy.

[0005] In a first aspect, the present invention provides a multi-point force measuring device for a knee joint measuring pad, comprising:

[0006] A fixed frame includes an upper fixed plate, a lower fixed plate, and multiple support columns disposed between the upper fixed plate and the lower fixed plate;

[0007] A multi-point force measuring mechanism includes an overall mechanical structure and a stacked plate structure. The overall mechanical structure includes a total spoke force sensor and an upper pressure assembly disposed on the upper fixed plate. The upper pressure assembly is used to contact the upper shell of the gasket to be tested. The total spoke force sensor is located between the upper pressure assembly and the upper fixed plate and is used to obtain the total pressure applied to the upper shell of the gasket to be tested.

[0008] The stacked plate structure includes multiple pressure detection plates, multiple force guide columns, and multiple miniature spoke force sensors. The multiple miniature spoke force sensors are staggered in different pressure detection plates according to preset positions, and the force is transmitted by the force guide columns abutting against the preset position of the upper shell of the gasket to be tested, so as to realize the detection of the pressure at the corresponding position of the upper shell of the gasket to be tested.

[0009] A lifting mechanism is provided between the lower fixed plate and the stacked plate structure, and is used to drive the stacked plate structure to lift and lower in order to install and fix the upper shell of the test pad.

[0010] In one possible implementation, the stacked plate structure further includes a guide post fixing plate and a bottom support plate, with each pressure detection plate located between the guide post fixing plate and the bottom support plate. The upper end of the guide post is movably sleeved on the guide post fixing plate for contacting a preset position on the upper shell of the gasket to be tested.

[0011] In one possible implementation, each of the pressure detection plates is provided with a sensor mounting hole, and the miniature spoke force sensor is disposed in the sensor mounting hole; except for the pressure detection plate closest to the bottom support plate, the other pressure detection plates are provided with a force guiding through hole for the force guiding column to pass through.

[0012] In one possible implementation, the pressure detection plates located on different layers have different sensor mounting holes, and the number of layers of the pressure detection plates and the arrangement of the sensor mounting holes are determined by the pressure acquisition point location on the upper shell of the gasket to be tested and the size of the selected micro spoke force sensor.

[0013] In one possible implementation, the stacked plate structure further includes guide posts, and the pressure detection plate, the bottom support plate, and the guide post fixing plate are all provided with guide holes; the upper pressure assembly is provided with guide sleeves, and the guide sleeves are arranged in a one-to-one correspondence with the guide posts; the guide posts pass through the guide holes on the pressure detection plate, the bottom support plate, and the guide post fixing plate in sequence, the upper end of the guide post is fitted with the guide sleeve, and the lower end of the guide post is connected to the bottom support plate through a flange.

[0014] In one possible implementation, a plurality of the guide holes are arranged around the sensor mounting holes and are symmetrically arranged about the pressure detection plate.

[0015] In one possible implementation, the pressure detection plate further includes connection holes and wiring channels; the wiring channels are used to arrange the wiring of the miniature spoke force sensor, and the connection holes are used to fix all the pressure detection plates together into a single structure via connectors.

[0016] In one possible implementation, the upper pressure assembly includes an adapter plate and a contoured pressure head. The adapter plate is used to connect to the total spoke force sensor, and the shape of the contoured pressure head is consistent with the shape of the test surface of the upper shell of the test pad, for direct contact with the test surface of the upper shell of the test pad.

[0017] In one possible implementation, the lifting mechanism is a scissor-type lifting slide, which is fixedly connected to the bottom support plate via a connector.

[0018] Secondly, the present invention also provides a multi-point force measurement method for a knee joint measuring pad, based on the multi-point force measurement device for a knee joint measuring pad as described in the first aspect, the force measurement method comprising:

[0019] The lifting mechanism is controlled to descend to adjust the height of the stacked plate structure, thereby separating the stacked plate structure from the pressure assembly;

[0020] The upper shell of the gasket to be tested is placed at a predetermined position between the stacked plate structure and the upper pressure assembly;

[0021] Gradually control the lifting mechanism to rise to adjust the height of the stacked plate structure, bring the upper pressure component close to the stacked plate structure and apply a preset pressure, thereby obtaining the pressure value of each guide column transmitted to the corresponding micro spoke force sensor under the preset pressure.

[0022] This invention has at least the following technical effects:

[0023] The present invention provides a multi-point force measuring device and method for knee joint measuring pads. This testing device fixes the upper shell of the knee joint measuring pad in a narrow space between an upper fixing plate and a stacked plate structure. By measuring the force transmission at multiple measuring points of the soft upper shell within this small space, the pressure loss value at each testing point is obtained. Appropriate pressure loss compensation ensures the measurement accuracy after the measuring pad is implanted into the knee joint. Furthermore, unqualified measuring pads are reworked or marked as defective products in advance, avoiding measurement errors introduced by repeated installation of pads with low measurement accuracy. This improves the production, installation, and measurement efficiency and accuracy of the measuring pads. Attached Figure Description

[0024] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the overall structure of a multi-point force measuring device for a knee joint measuring pad provided in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of a fixing frame for a multi-point force measuring device for a knee joint measuring pad provided in an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of a stacked plate structure for a multi-point force measuring device for knee joint measuring pads provided in an embodiment of the present invention;

[0028] Figure 4 This is a schematic diagram of the lifting mechanism of a multi-point force measuring device for a knee joint measuring pad provided in an embodiment of the present invention;

[0029] Figure 5 Provided for embodiments of the present invention Figure 1 Exploded view;

[0030] Figure 6 Provided for embodiments of the present invention Figure 3 Exploded view;

[0031] Figure 7 This is a schematic diagram of the structure of the guide rod fixing plate provided in an embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram of the structure of the first layer pressure detection plate provided in an embodiment of the present invention;

[0033] Figure 9 This is a schematic diagram of the structure of the second-layer pressure detection plate provided in an embodiment of the present invention;

[0034] Figure 10 This is a schematic diagram of the structure of the third-layer pressure detection plate provided in an embodiment of the present invention;

[0035] Figure 11 This is a schematic diagram of the structure of the fourth layer pressure detection plate provided in an embodiment of the present invention;

[0036] Figure 12 This is a schematic diagram of the structure of the bottom support plate provided in an embodiment of the present invention;

[0037] Figure 13 This is a schematic diagram of the structure of the inner side of the upper shell of the test pad provided in an embodiment of the present invention;

[0038] Figure 14 This is a flowchart of a multi-point force measurement method for a knee joint measuring pad provided in an embodiment of the present invention.

[0039] In the picture:

[0040] 100-Fixed frame; 101-Upper fixing plate; 102-Total wheel spoke force sensor; 103-Support column; 104-Lower fixing plate; 105-First screw; 106-Support foot pad; 107-Second screw; 108-Third screw; 109-Fourth screw; 110-Fifth screw;

[0041] 200-Multi-point force measuring mechanism; 201-Guide sleeve; 202-Contouring pressure head; 203-Sixth screw; 204-Force guide column; 205-Force guide column fixing plate; 206-First layer pressure detection plate; 207-Second pressure detection plate; 208-Third layer pressure detection plate; 209-Fourth layer pressure detection plate; 210-Seventh screw; 211-Bottom support plate; 212-Guide column; 213-Eighth screw; 214-Miniature spoke force sensor; 215-Upper shell of the gasket to be tested; 2151-Protruding point position; 216-Wire routing groove; 217-Sensor mounting hole; 218-Force guide through hole; 219-Connection hole; 220-Guide hole; 221-Mounting hole;

[0042] 300 - Lifting mechanism. Detailed Implementation

[0043] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein. It will be understood by those skilled in the art that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms.

[0045] Combination Figures 1 to 13 As shown, the present invention provides a multi-point force measuring device for knee joint measuring pads, including: a fixed frame 100, a multi-point force measuring mechanism 200, and a lifting mechanism 300.

[0046] Specifically, the fixed frame 100 includes an upper fixed plate 101, a lower fixed plate 104, and multiple support columns 103 disposed between the upper fixed plate 101 and the lower fixed plate 104. The lower fixed plate 104 is connected to the bottom end of each support column 103 by a first screw 105, and the upper fixed plate 101 is connected to the top end of each support column 103 by a second screw 107, thereby forming the support structure of the entire force measuring device. Optionally, support pads 106 are installed at the bottom of the lower fixed plate 104. The support pads 106 are made of rubber, which helps to improve the stability of the entire support structure.

[0047] The multi-point force measuring mechanism 200 includes an overall mechanical structure and a stacked plate structure. The overall mechanical structure includes a total wheel spoke force sensor 102 and an upper pressure assembly. The total wheel spoke force sensor 102 and the upper pressure assembly are mounted on the upper fixed plate 101. Specifically, the total wheel spoke force sensor 102 is fixed to the upper fixed plate 101 by a third screw 108, and the upper pressure assembly is connected to the upper pressure assembly via a connector. The upper pressure assembly is used to contact the upper shell 215 of the gasket to be tested. The total wheel spoke force sensor 102 is located between the upper pressure assembly and the upper fixed plate 101, and is used to obtain the total pressure applied to the upper shell 215 of the gasket to be tested.

[0048] Optionally, the pressure assembly includes an adapter plate and a contoured pressure head 202. The adapter plate is used to connect to the total wheel spoke force sensor 102, and the shape of the contoured pressure head 202 is consistent with the shape of the test surface of the upper shell 215 of the test pad, so as to directly contact the test surface of the upper shell 215 of the test pad to improve the pressure transmission accuracy and sensitivity of the pressure test point.

[0049] Furthermore, the stacked plate structure includes multiple pressure detection plates (shown as four layers in the figure, namely the first pressure detection plate 206, the second pressure detection plate 207, the third pressure detection plate 208, and the fourth pressure detection plate 209), multiple force guide columns 204, and multiple miniature spoke force sensors 214. The multiple miniature spoke force sensors 214 are staggered in different pressure detection plates according to preset positions, and the force is transmitted by the force guide columns 204 abutting against the preset position of the upper shell 215 of the test pad, so as to realize the detection of the pressure at the corresponding position of the upper shell 215 of the test pad.

[0050] The lifting mechanism 300 is disposed between the lower fixing plate 104 and the stacking plate structure. The stacking plate structure is connected to the lifting mechanism 300 by the fourth screw 109. The bottom of the lifting mechanism 300 is connected to the lower fixing plate 104 by the fifth screw 110. The lifting mechanism 300 is used to drive the stacking plate structure to lift and lower to realize the installation and fixation of the upper shell 215 of the test pad. At the same time, the lifting mechanism 300 can also apply a preset pressure to the upper shell 215 of the test pad by adjusting the lifting height. That is, after the lifting mechanism 300 moves to clamp the upper shell 215 of the test pad, it can continue to rise to apply pressure (preload). Different pressures can be applied by adjusting different lifting heights.

[0051] The multi-point force measuring device for knee joint measuring pads provided by this invention fixes the upper shell of the knee joint measuring pad in a narrow space between an upper fixing plate and a stacked plate structure. By measuring the force transmission at multiple measuring points of the soft upper shell within this small space, the pressure loss value at each measuring point is obtained. Appropriate pressure loss compensation ensures the measurement accuracy after the measuring pad is implanted into the knee joint. Furthermore, unqualified measuring pads are reworked in advance or marked as defective products, avoiding measurement errors introduced by repeated installation of pads with low measurement accuracy. This is beneficial to improving the production, installation, and measurement efficiency and accuracy of measuring pads.

[0052] In some embodiments, the stacked plate structure further includes a force guide post fixing plate 205 and a bottom support plate 211. Each pressure detection plate is located between the force guide post fixing plate 205 and the bottom support plate 211. The upper end of the force guide post 204 is movably sleeved on the force guide post fixing plate 205 for contacting a preset position of the upper shell 215 of the test pad.

[0053] Optionally, each pressure detection plate is provided with a sensor mounting hole 217, and the miniature spoke force sensor 214 is disposed in the sensor mounting hole 217; the number of pressure detection plates is at least two, and except for the pressure detection plate closest to the bottom support plate 211, the remaining pressure detection plates are provided with a force guiding through hole 218 for the force guiding column 204 to pass through.

[0054] It should be noted that the pressure detection plates located on different layers have different sensor mounting holes 217. The number of layers of the pressure detection plates and the arrangement of the sensor mounting holes 217 need to be determined according to the pressure acquisition point position of the upper shell 215 of the test pad and the size of the selected miniature spoke force sensor 214. In this embodiment, no specific limitation is required.

[0055] Optionally, the stacked plate structure further includes guide posts 212. Guide holes 220 are provided on the pressure detection plate, the bottom support plate 211, and the guide post fixing plate 205. The upper pressure assembly is provided with a guide sleeve 201, which is correspondingly arranged with the guide posts 212. The guide posts 212 pass through the guide holes 220 on the pressure detection plate, the bottom support plate 211, and the guide post fixing plate 205 in sequence. The upper end of the guide post 212 is fitted with the guide sleeve 201, and the lower end of the guide post 212 is axially limited to the bottom support plate 211 by a flange and fixedly connected by an eighth screw 213.

[0056] Optionally, a plurality of guide holes 220 are arranged around the sensor mounting hole 217 and symmetrically arranged about the pressure detection plate, which helps to improve the connection stability of the entire stacked plate structure.

[0057] Optionally, the pressure detection plate also includes connection holes 219 and wiring channels 216; the wiring channels 216 are used to arrange the wiring of the miniature spoke force sensor 214, and the connection holes 219 are used to fix all the pressure detection plates into a whole structure through connectors (sixth screws 203). It should be noted that the force guide column fixing plate 205 and the bottom support plate 211 are also provided with connection holes 219, and the plates are connected into a whole by long sixth screws 203.

[0058] Optionally, the lifting mechanism 300 is a scissor-type lifting slide. The lifting slide is fixedly connected to the bottom support plate 211 through a connector. The scissor-type lifting slide facilitates the gradual application of pressure, making it convenient to pre-tighten and pressurize the upper shell 215 of the test pad, and will not damage the test workpiece due to sudden pressure changes.

[0059] The following describes the specific structure of the stacked plate structure. According to the order from top to bottom in the figure, the four layers are: guide column fixing plate 205, first layer pressure detection plate 206, second layer pressure detection plate 207, third layer pressure detection plate 208, fourth layer pressure detection plate 209, and bottom support plate 211. The purpose of setting these four layers of pressure detection plates is to distribute the pressure values ​​of the pressure test points on the upper shell of the measuring pad to different pressure detection plates. This is because multiple micro-spoke force sensors 214 cannot be densely arranged in a single layer of pressure detection plate. The micro-spoke force sensors 214 in different layers realize the pressure transmission value detection of the corresponding test points through the corresponding guide column 204.

[0060] Specifically, such as Figure 7 As shown, the guide post fixing plate 205 is also provided with multiple guide post 204 positioning holes. The arrangement and number of guide post 204 positioning holes correspond one-to-one with the protrusion positions 2151 of the upper shell 215 of the test pad (the specific protrusion positions 2151 of the upper shell 215 of the test pad are as follows). Figure 13 As shown), the guide post 204 passes through the positioning hole of the guide post 204. Since the size of the guide post 204 near the protrusion point 2151 is larger, the upper end of the guide post 204 can be stuck outside the positioning hole of the guide post 204. The upper ends of all the guide posts 204 are basically on the same horizontal plane, which makes it easy to contact the protrusion point 2151 on the inner side of the upper shell 215 of the pad to be tested.

[0061] like Figure 8As shown, the first-layer pressure detection plate 206 has guide holes 220 through the guide post 212, 10 sensor mounting holes 217 for mounting the first-layer miniature spoke force sensor 214, a wiring groove 216 on its back, 10 high-precision force guiding through holes 218 positioned directly above the force-bearing surface of the second-layer spoke force sensor and coaxially for mounting the force guiding post 204, and 10 through holes of the force guiding post 204 that contact the third and fourth-layer spoke force sensors. The rest are flat surfaces or have added installation position markings to facilitate the placement of the first-layer miniature spoke force sensor 214.

[0062] like Figure 9 As shown, in addition to the guide hole 220 through the guide post 212, the second layer plate also has 10 sensor mounting holes 217 for mounting the second layer wheel spoke force sensor and a wiring groove 216 on its back, as well as 6 high-precision force guiding through holes 218 positioned directly above the force-bearing surface of the third layer wheel spoke force sensor and coaxially for mounting the force guiding post 204. There are also 4 through holes of the force guiding post 204 that contact the fourth layer wheel spoke force sensor. The rest are flat surfaces or have added installation position marks to facilitate the placement of the second layer miniature wheel spoke force sensor 214.

[0063] like Figure 10 As shown, in addition to the guide hole 220 through the guide post 212, the third layer plate also has six sensor mounting holes 217 for mounting the miniature spoke force sensor 214 of the third layer, as well as a wiring groove 216 on its back, and four high-precision force guiding through holes 218 positioned directly above the force-bearing surface of the fourth layer spoke force sensor and coaxially for mounting the force guiding post 204; the rest are flat surfaces or have added installation position marks to facilitate the placement of the miniature spoke force sensor 214 of the third layer.

[0064] like Figure 11 As shown, in addition to the guide hole 220 through the guide post 212, the fourth layer plate also has four sensor mounting holes 217 for mounting the miniature wheel spoke force sensor 214 of the fourth layer and a wiring groove 216 on its back. The rest are flat surfaces, or have added mounting position markings to facilitate the placement of the miniature wheel spoke force sensor 214 of the fourth layer.

[0065] like Figure 12As shown, the bottom support plate 211 is provided with guide holes 220 through which guide posts 212 pass. The guide posts 212 pass through the guide holes 220 of each layer from the bottom support plate 211 and are connected to the guide sleeve 201 on the contour pressure head 202. In addition, the bottom support plate 211 is also provided with connection holes 219 for connecting with the lifting mechanism 300 below. The mounting holes 221 on the bottom support plate 211 are fixedly connected to the lifting mechanism 300 by the seventh screw 210. The lifting mechanism 300 drives the bottom support plate 211 and the entire stacked plate structure to rise and fall, thereby realizing the installation and pressure pre-tightening of the upper shell 215 of the test pad.

[0066] The second aspect, such as Figure 14 As shown, this embodiment of the invention also provides a multi-point force measurement method for a knee joint measuring pad, based on the multi-point force measurement device for a knee joint measuring pad as described in the first aspect, the force measurement method comprising:

[0067] S100 controls the lifting mechanism to descend in order to adjust the height of the stacked plate structure, thereby separating the stacked plate structure from the pressure assembly.

[0068] S200, the upper shell of the gasket to be tested is placed at a preset position between the stacked plate structure and the stacked plate structure;

[0069] S300, gradually control the lifting mechanism to rise to adjust the height of the stacked plate structure, bring the upper pressure component close to the stacked plate structure and apply a preset pressure, thereby obtaining the pressure value of each guide column transmitted to the corresponding micro spoke force sensor under the preset pressure.

[0070] The multi-point force measurement method provided in this invention uses a testing device to fix the upper shell of the knee joint measuring pad in a narrow space between the upper fixing plate and the stacked plate structure. By measuring the force transmission at multiple measuring points of the soft upper shell in the small space, the pressure loss value of the corresponding test point is obtained. The measurement accuracy after the measuring pad is implanted into the knee joint is ensured through corresponding pressure loss compensation. Furthermore, unqualified measuring pads are reworked in advance or marked as defective products to avoid measurement errors caused by repeated installation of pads with low measurement accuracy. This is beneficial to improving the production, installation, and measurement efficiency and accuracy of the measuring pad.

[0071] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, and processes discussed in this invention can be alternated, modified, combined, or deleted. Furthermore, other steps, measures, and schemes in the various operations, methods, and processes discussed in this invention can also be alternated, modified, rearranged, decomposed, combined, or deleted. Furthermore, steps, measures, and schemes in the prior art that are similar to those disclosed in this invention can also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0072] In the description of this invention, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0073] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0074] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0075] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-point force measuring device for knee joint measuring pads, characterized in that, include: A fixed frame includes an upper fixed plate, a lower fixed plate, and multiple support columns disposed between the upper fixed plate and the lower fixed plate; A multi-point force measuring mechanism includes an overall mechanical structure and a stacked plate structure. The overall mechanical structure includes a total spoke force sensor and an upper pressure assembly disposed on the upper fixed plate. The upper pressure assembly is used to contact the upper shell of the gasket to be tested. The total spoke force sensor is located between the upper pressure assembly and the upper fixed plate and is used to obtain the total pressure applied to the upper shell of the gasket to be tested. The stacked plate structure includes multiple pressure detection plates, multiple force guide columns, and multiple miniature spoke force sensors. The multiple miniature spoke force sensors are staggered in different pressure detection plates according to preset positions, and the force is transmitted by the force guide columns abutting against the preset position of the upper shell of the gasket to be tested, so as to realize the detection of the pressure at the corresponding position of the upper shell of the gasket to be tested. A lifting mechanism is provided between the lower fixed plate and the stacked plate structure, and is used to drive the stacked plate structure to lift and lower in order to install and fix the upper shell of the test pad.

2. The multi-point force measuring device for knee joint measuring pads according to claim 1, characterized in that, The stacked plate structure also includes a guide column fixing plate and a bottom support plate. Each pressure detection plate is located between the guide column fixing plate and the bottom support plate. The upper end of the guide column is movably sleeved on the guide column fixing plate for contacting a preset position on the upper shell of the test pad.

3. The multi-point force measuring device for knee joint measuring pads according to claim 2, characterized in that, Each pressure detection plate is provided with a sensor mounting hole, and the miniature spoke force sensor is installed in the sensor mounting hole; except for the pressure detection plate closest to the bottom support plate, the other pressure detection plates are provided with a force guiding through hole for the force guiding column to pass through.

4. The multi-point force measuring device for knee joint measuring pads according to claim 3, characterized in that, The pressure detection plates located on different layers have different sensor mounting holes. The number of layers of the pressure detection plates and the arrangement of the sensor mounting holes are determined by the pressure acquisition point location on the upper shell of the gasket to be tested and the size of the selected miniature spoke force sensor.

5. The multi-point force measuring device for knee joint measuring pads according to claim 3, characterized in that, The stacked plate structure also includes guide columns, and guide holes are provided on the pressure detection plate, the bottom support plate, and the guide column fixing plate. The upper pressure assembly is provided with a guide sleeve, and the guide sleeve is configured to correspond one-to-one with the guide post; the guide post passes through the guide holes in the pressure detection plate, the bottom support plate and the guide post fixing plate in sequence, the upper end of the guide post is installed in conjunction with the guide sleeve, and the lower end of the guide post is connected to the bottom support plate through a flange.

6. The multi-point force measuring device for knee joint measuring pads according to claim 5, characterized in that, The plurality of guide holes are arranged around the sensor mounting holes and are symmetrically arranged about the pressure detection plate.

7. The multi-point force measuring device for knee joint measuring pads according to claim 3, characterized in that, The pressure detection plate also includes connection holes and wiring channels; the wiring channels are used to arrange the wiring of the miniature spoke force sensor, and the connection holes are used to fix all the pressure detection plates into a whole structure through connectors.

8. The multi-point force measuring device for knee joint measuring pads according to claim 1, characterized in that, The upper pressure assembly includes an adapter plate and a contoured pressure head. The adapter plate is used to connect to the total wheel spoke force sensor, and the shape of the contoured pressure head is consistent with the shape of the test surface of the upper shell of the test pad, so as to directly contact the test surface of the upper shell of the test pad.

9. The multi-point force measuring device for knee joint measuring pads according to claim 2, characterized in that, The lifting mechanism is a scissor-type lifting slide, which is fixedly connected to the bottom support plate via a connector.

10. A multi-point force measurement method for a knee joint measuring pad, characterized in that, Based on the multi-point force measuring device for knee joint measuring pads as described in any one of claims 1 to 9, the force measuring method includes: The lifting mechanism is controlled to descend to adjust the height of the stacked plate structure, thereby separating the stacked plate structure from the pressure assembly; The upper shell of the gasket to be tested is placed at a predetermined position between the stacked plate structure and the upper pressure assembly; Gradually control the lifting mechanism to rise to adjust the height of the stacked plate structure, bring the upper pressure component close to the stacked plate structure and apply a preset pressure, thereby obtaining the pressure value of each guide column transmitted to the corresponding micro spoke force sensor under the preset pressure.

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