Multifunctional medical bone screw testing platform

Abstract

A multifunctional medical bone screw testing platform comprises a load applying unit and a screw testing tool. The load applying unit comprises a linear module and a reference mounting platform; the linear module is erected on one side of the top of the reference mounting platform; the screw test tool comprises a rotation module, a torque test module, a pull-out test module and a loading installation platform. A rotating adapter disc of the rotating module is mounted on the other side of the top of the reference mounting platform and is driven by a rotating motor to horizontally rotate; the loading mounting platform is positioned above the rotary switching disc and is connected with the module sliding block; the torque test module is installed at the bottom of the loading installation platform, and the pull-out test module is detachably installed at the bottom of the loading installation platform and covers the periphery of the torque test module. According to the scheme, the test structure is self-centered, the test units are modularized, the test functions are diversified, the test structure is compact, and self-tapping force test, screw-in and screw-out test and pull-out test load and judgment of standard requirements can be accurately realized.

Description

Technical Field

[0001] The utility model relates to the technical field of bone screw testing, in particular to a multifunctional medical bone screw testing platform. Background Art

[0002] When bones are injured, medical bone screws are the most common medical device used to restore the load-bearing state of bones. In order to evaluate the implantation performance of screws, the screw self-tapping force, screw-in and screw-out torque, pull-out force, fracture torque and fracture torsion angle performance are often evaluated. Among them, the fracture torque and fracture torsion angle can be directly tested with a common torsion testing machine. The screw self-tapping force, screw-in and screw-out torque, and pull-out force need to be tested on a machine that has both axial and rotational motion. According to the standard test requirements, the screw self-tapping force is the pressure when the screw displacement and torque increase significantly during the gradual increase of pressure (2±1 N / s) and the rotation of the screw (30r / min). According to the standard judgment requirements, when determining the screw self-tapping force, the test load should be maintained or unloaded and the tapping should continue until the number of turns required by the standard is reached. The screw-in and screw-out torque is the maximum torque within the specified number of turns when the screw is screwed into or out of the hole at the standard rotation speed. The pull-out force is the maximum load when the screw is pulled out at the standard axial pull-out speed after the screw is screwed into a certain depth.

[0003] Traditionally, fatigue testing machines or static testing machines are often used to achieve axial force / displacement control and rotation control. However, according to actual use and current relevant research results, directly using these machines usually cannot obtain results that meet standard requirements.

[0004] First, most machines cannot simultaneously control torsional and axial motion, which means that before using these machines for testing, it is necessary to pre-drill guide holes and then clamp them for testing. However, this cannot ensure the alignment of the installed guide holes and axial loads, which directly affects the validity of the results.

[0005] Second, if the current mainstream fatigue testing machine is to meet the Self-tapping test, screw-in and screw-out test, and pull-out test test , a large force machine must be used, but a large force machine is usually equipped with a large force sensor, and the range of this sensor does not meet the test needs of small forces. If another sensor is required, the cost will increase linearly.

[0006] In addition, the test stroke of the current mainstream electromagnetic fatigue testing machine cannot meet the stroke requirements of the medical bone screw testing standards.

[0007] Therefore, in response to the testing requirements of medical bone screws, the utility model provides a multifunctional medical bone screw testing platform to solve the above problems. Utility Model Content

[0008] The utility model aims to provide a multifunctional medical bone screw testing platform, which can effectively evaluate the self-tapping force, screw-in and screw-out torque and pull-out force of medical bone screws, and has the advantages of multifunctionality, low cost, compact structure and easy use.

[0009] In order to achieve the above purpose, the solution of the utility model is:

[0010] A multifunctional medical bone screw testing platform, comprising a load applying unit and a screw testing tool;

[0011] The load application unit includes a linear module and a reference mounting platform;

[0012] The linear module is erected on one side of the top of the reference installation platform, and the module slider of the linear module is driven by the module motor to slide back and forth in the vertical direction;

[0013] The screw testing tool comprises a rotation module, a torque testing module, a pull-out testing module and a loading and mounting platform;

[0014] The rotating module includes a rotating motor and a rotating adapter plate, wherein the rotating adapter plate is installed on the other side of the top of the reference mounting platform, and the rotating adapter plate is driven by the rotating motor to rotate horizontally;

[0015] The loading and mounting platform is located above the rotating adapter plate and is connected and fixed to the module slider;

[0016] The torque test module includes a compression-torsion integrated sensor and a chuck, and the compression-torsion integrated sensor and the chuck are sequentially installed up and down at the bottom of the loading and mounting platform;

[0017] The pull-out test module includes a pull-out test tank, a pull-out test sensor and a pull-out test fixture. The pull-out test tank is detachably mounted on the bottom of the loading and mounting platform and is covered on the outer periphery of the torque test module. The pull-out test sensor and the pull-out test fixture are sequentially mounted below the pull-out test tank.

[0018] The centers of the chuck, the extraction test fixture and the rotating adapter plate are located on the same vertical axis.

[0019] Furthermore, the linear module is a linear screw module structure;

[0020] The module slider is slidably matched with the screw of the linear screw module, the module motor is installed below the reference installation platform, and the power shaft of the module motor is connected to the screw through a coupling;

[0021] The module motor is a servo motor.

[0022] Furthermore, the rotating motor is installed below the reference mounting platform, and the bottom of the rotating adapter plate is installed on the reference mounting platform through an axial load-bearing bearing, and the power shaft of the rotating motor extends upward from the reference mounting platform and is connected to the rotating adapter plate. The rotating motor is a stepping motor.

[0023] Furthermore, a base, a first vertical plate and a second vertical plate are provided below the reference installation platform of the load application unit; the reference installation platform is located above the base, and the first vertical plate and the second vertical plate are respectively provided on both sides between the reference installation platform and the base.

[0024] The positioning design of the reference installation platform is the key to ensuring the alignment of the servo motor shaft and the linear module shaft, the alignment of the stepper motor shaft and the torque test module, and controlling the plane and horizontal plane deviation of the reference installation platform.

[0025] Furthermore, it also includes an installation and positioning tool; the installation and positioning tool includes a centering rod, which is detachably installed on the chuck and maintained in a vertical direction; a center hole is provided in the center of the rotating adapter plate, the inner diameter of the center hole matches the outer diameter of the centering rod, and the power shaft of the rotating motor is used to connect with the center hole.

[0026] Furthermore, a positioning reference groove and a positioning through hole are provided at the rear end of the loading and installation platform. The positioning reference groove is set on the top of the module slider and is locked and fixed to the top surface of the module slider through the positioning through hole by screws; a first support block and a second support block are also provided on both sides below the loading and installation platform, and the rear ends of the first support block and the second support block are connected to the front side of the module slider.

[0027] Furthermore, the rotation module also includes a dovetail cross slide and a self-centering vise without an extension rod;

[0028] The dovetail cross slide is installed on the top of the rotating adapter plate, and the self-centering vise without extension rod is installed on the top of the dovetail cross slide.

[0029] Furthermore, the torque testing module also includes a first adapter plate and a second adapter plate, which are installed up and down in sequence and are located between the compression-torsion integrated sensor and the chuck; the chuck is a three-jaw chuck.

[0030] Furthermore, a boss having the same diameter as the compression-torsion integrated sensor is provided at the bottom of the loading and mounting platform, and a plurality of screw through holes extending vertically are provided on the boss for fixing the torque test module;

[0031] A circular ring-shaped positioning groove for installing the extraction test module is also provided at the bottom of the loading and mounting platform. The circular ring-shaped positioning groove surrounds the outer circumference of the boss. The outer diameter of the circular ring-shaped positioning groove is consistent with the outer diameter of the extraction test tank. A plurality of vertically penetrating installation through holes are provided in the circular ring-shaped positioning groove for fixing the extraction test module.

[0032] Furthermore, a wire outlet matching the output signal line of the compression-twist integrated sensor is provided in the annular positioning groove, and the signal line of the compression-twist integrated sensor passes through the wire outlet; and the mounting through holes in the annular positioning groove are unevenly distributed.

[0033] After adopting the above technical scheme, the test platform provided by the utility model for evaluating the self-tapping force, screw-in and screw-out torque and pull-out force of medical bone screws at least has force and position control logic, modular testing, self-centering, and can achieve standard requirements.

[0034] (1) The utility model has the characteristics of self-centering test structure, modular test unit, diversified test functions, compact test structure, force control and displacement control modes, and can accurately realize the self-tapping force test, screw-in and screw-out test, and pull-out test load and judgment required by the standard.

[0035] (2) Through the self-centering design of the structure, the processes of drilling, tapping, screwing in, screwing out and pulling out can be connected in series during the screw test, without the need for external drilling and then installation and centering operations, which reduces the deviation of the test results caused by the installation operation after drilling, and can obtain test results with higher repeatability and better reflect the actual performance of the screw. At the same time, this series connection of test processes also meets the test requirements of the standard.

[0036] (3) The test unit adopts a modular design. On the one hand, it can realize the convenient switching of multiple functions. On the other hand, it can avoid the misalignment of the upper and lower test modules caused by repeated disassembly, thereby ensuring the validity of the test data.

[0037] (4) The test unit adopts a linear module structure, so the test stroke can cover the testing requirements of all current specifications (mainly different lengths) of medical bone screws.

[0038] (5) The test platform of the utility model has both force control and displacement control modes, which can realize force loading and displacement loading with any loading rate and waveform required by the standard. Moreover, the utility model can also realize the self-attack force determination and maintenance operation required by the standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a schematic diagram of a self-tapping test in a preferred embodiment of the utility model;

[0040] Figure 2 It is a schematic diagram of a pull-out test in a preferred embodiment of the utility model;

[0041] Figure 3 This is a schematic diagram of centering assembly in a preferred embodiment of the utility model;

[0042] Figure 4 This is a schematic diagram of the upper surface of the loading and mounting platform in the preferred embodiment of the utility model;

[0043] Figure 5 It is a schematic diagram of the lower side of the loading and installation platform in the preferred embodiment of the utility model;

[0044] Figure 6 It is a partial structural diagram of a preferred embodiment of the utility model.

[0045] Explanation of reference numerals: load application unit A, linear module 1, module slider 11, module motor 12, screw 13, coupling 14, rib 15, reference mounting platform 2, base 21, first vertical plate 22, second vertical plate 23, screw test fixture B, rotation module 3, rotation motor 31, rotation adapter plate 32, dovetail cross slide 33, self-centering vise without extension rod 34, torque test module 4, compression-torsion integrated sensor 41, chuck 42, first adapter plate 43, second adapter plate 44, pull-out test module 5, pull-out test tank 51, pull-out test sensor 52, pull-out test fixture 53, loading mounting platform 6, first support block 61, second support block 62, circular positioning groove 63, screw through hole 64, positioning reference groove 65, positioning through hole 66, installation positioning fixture C, centering rod 7. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0047] like Figures 1 to 5 As shown, a multifunctional medical bone screw testing platform of the utility model comprises a load applying unit A and a screw testing tool B;

[0048] The load applying unit A comprises a linear module 1 and a reference mounting platform 2;

[0049] The linear module 1 is erected on one side of the top of the reference installation platform 2, and the module slider 11 of the linear module 1 is driven by the module motor 12 to slide back and forth in the vertical direction;

[0050] The screw testing tool B comprises a rotation module 3, a torque testing module 4, a pull-out testing module 5 and a loading and mounting platform 6;

[0051] The rotating module 3 includes a rotating motor 31 and a rotating adapter plate 32. The rotating adapter plate 32 is installed on the other side of the top of the reference installation platform 2. The rotating adapter plate 32 is driven by the rotating motor 31 to rotate horizontally.

[0052] The loading and mounting platform 6 is located above the rotating adapter plate 32 and is connected and fixed to the module slider 11;

[0053] The torque test module 4 includes a compression-torsion integrated sensor 41 and a chuck 42, and the compression-torsion integrated sensor 41 and the chuck 42 are sequentially mounted on the bottom of the loading and mounting platform 6;

[0054] The pull-out test module 5 includes a pull-out test tank 51, a pull-out test sensor 52 and a pull-out test fixture 53. The pull-out test tank 51 is detachably mounted on the bottom of the loading and mounting platform 6 and is covered on the outer periphery of the torque test module 4. The pull-out test sensor 52 and the pull-out test fixture 53 are sequentially mounted below the pull-out test tank 51.

[0055] The centers of the chuck 42 , the extraction test fixture 53 and the rotating adapter plate 32 are located on the same vertical axis.

[0056] Thus, by adopting the above structure, first, a standard test block (not shown) can be installed on the rotating adapter plate 32, and then a drill bit (not shown) can be installed on the chuck 42. Thus, the rotating adapter plate 32 drives the standard test block to rotate, and the linear module 1 drives the drill bit to slide downward, so as to realize the drilling of the standard test block, so as to ensure that in the subsequent testing process, the guide hole drilled out and the chuck 42 and the pull-out test fixture 53 are aligned.

[0057] Second, see Figure 1 The torque test module 4 adopts force control logic. After the chuck 42 of the torque test module 4 is used to clamp the screw bit (the screw bit is not shown in the figure, and the existing structure can be used), the rotating adapter plate 32 drives the standard test block after drilling to rotate, and the linear module 1 drives the screw to slide back and forth up and down at the same time, and cooperates with the compression and torsion integrated sensor 41 to realize the screw self-tapping test and screw-in and screw-out test.

[0058] Finally, the pull-out test module 5 adopts displacement control logic. The pull-out test module 5 can be quickly assembled into the loading installation platform 6 through the pull-out test tank 51, thereby ensuring the centering of the test tooling; then the linear module 1 is used to drive the screw to slide back and forth up and down to realize the pull-out test of the screw.

[0059] In combination with the above, the test platform of the utility model has the advantages of easy centering, modular test unit, diversified test functions, compact test platform, force control and displacement control modes, and can realize the self-tapping force test, screw-in and screw-out test and pull-out test required by the standard. Through the self-centering design of the structure and the modular design of the test unit, the processes of drilling, tapping, screwing in, screwing out and pull-out test can be connected in series in the test of the screw, without the need for external drilling in advance and installation centering operations, reducing the deviation of the test results caused by the installation operation after drilling, and obtaining a test result with higher repeatability and better reflection of the actual performance of the screw. At the same time, the series connection of this test process also meets the test requirements of the standard. The test unit adopts a modular design, which can also avoid the occurrence of the situation that the upper and lower test modules are not centered due to repeated disassembly, and can also ensure the validity of the test data. In addition, because the test unit adopts a linear module 1 structure, the test stroke can cover the test requirements of medical bone screws of all current specifications (mainly different lengths).

[0060] In this embodiment, the linear module 1 takes a linear screw module structure as an example, the module slider 11 is slidably matched with the screw 13 of the linear screw module, the module motor 12 is installed below the reference mounting platform 2, and the power shaft of the module motor 12 is connected to the screw 13 through a coupling 14, and the module motor 12 can adopt a servo motor; the rotary motor 31 can also be installed below the reference mounting platform 2, and the bottom of the rotary adapter plate 32 can be installed on the reference mounting platform 2 through an axial load-bearing bearing (not shown), and the power shaft of the rotary motor 31 extends upward from the reference mounting platform 2 and is connected to the rotary adapter plate 32, and the rotary motor 31 can adopt a stepping motor.

[0061] A base 21, a first vertical plate 22 and a second vertical plate 23 are further provided below the reference mounting platform 2 of the load applying unit A in this embodiment; the reference mounting platform 2 is located above the base 21, and the first vertical plate 22 and the second vertical plate 23 are respectively erected on both sides between the reference mounting platform 2 and the base 21; with this structure, on the one hand, the deviation of the reference mounting platform 2 relative to the horizontal plane is ensured, and on the other hand, the space between the base 21, the first vertical plate 22, the second vertical plate 23 and the reference mounting platform 2 will be used to install stepper motors, servo motors and other control electrical components.

[0062] The positioning design of the reference installation platform 2 is the key to ensuring the alignment of the servo motor power shaft and the linear module 1 shaft, the stepper motor power shaft and the torque test module 4, and controlling the plane and horizontal plane deviation of the reference installation platform 2.

[0063] In this embodiment, an installation and positioning tool C is also included; the installation and positioning tool C includes a centering rod 7, which is detachably installed on the chuck 42 and maintained in a vertical direction; and a center hole (not shown) is provided in the center of the rotating adapter plate 32, and the inner diameter of the center hole matches the outer diameter of the centering rod 7, and the power shaft of the rotating motor 31 can be connected to the center hole.

[0064] On the one hand, the center hole is used to constrain the power shaft of the rotating motor 31, and on the other hand, it assists in centering the torque test module 4 on the loading installation platform 6; during centering, the chuck 42 clamps the centering rod 7, and controls the module slider 11 to move the centering rod 7 through the center hole of the rotating adapter plate 32 to ensure the centering accuracy of the test platform within the entire working stroke.

[0065] In order to center the torque test module 4 and the power shaft of the rotating motor 31, the axial load-bearing bearing and the rotating adapter plate 32 are installed on the reference mounting platform 2, and then the centering rod 7 is clamped by the chuck 42, and the module slider 11 is moved up and down to make the centering rod 7 pass through the rotating adapter plate 32 to achieve centering, and then the position of the compression-torsion integrated sensor 41 can be completely locked.

[0066] In this embodiment, refer to Figure 5 and Figure 6 The rear end of the loading and mounting platform 6 is provided with a positioning reference groove 65 and a positioning through hole 66, which facilitates the accurate positioning and installation of the loading and mounting platform 6 on the top surface of the module slider 11; specifically, the positioning reference groove 65 can be set on the top of the module slider 11, and is locked and fixed to the top surface of the module slider 11 by screws through the positioning through hole 66.

[0067] A first support block 61 and a second support block 62 may also be provided on both sides below the loading and installation platform 6, and the rear ends of the first support block 61 and the second support block 62 are both connected to the front of the module slider 11. After the loading and installation platform 6 is positioned and installed, the first support block 61 and the second support block 62 are connected to the loading and installation platform 6 and the module slider 11 by screws to support the loading and installation platform 6.

[0068] In this embodiment, the rotating module 3 may further include a dovetail cross slide 33 and a self-centering vise 34 without an extension rod;

[0069] The rotating motor 31, the dovetail cross slide 33, and the self-centering vise 34 without extension rod are installed on the reference installation platform 2 in sequence after the torque test module 4 is aligned; the dovetail cross slide 33 is installed on the top of the rotating adapter plate 32, and is used to adjust the position of the standard test block in the X and Y directions on the horizontal plane; the self-centering vise 34 without extension rod is installed on the top of the dovetail cross slide 33, and the self-centering vise 34 without extension rod is used to clamp the standard test block conveniently and reliably;

[0070] The self-centering vise 34 without an extension rod can tighten and loosen the vise by rotating the screw 13 (with positive and negative threads) of the vise through an external hexagonal socket or an internal hexagonal wrench; because it has no extension rod, the rotation center of the screw test fixture B can be closer to the horizontal distance of the linear module 1, so the length of the loading installation platform 6 can be smaller, so as to reduce the inertia ratio of the linear module 1 and the load application unit A as a whole relative to the rotating shaft of the servo motor, thereby improving the control frequency response of the system.

[0071] In this embodiment, the torque testing module 4 also includes a first adapter plate 43 and a second adapter plate 44, which are installed up and down in sequence and are located between the integrated compression and torque sensor 41 and the chuck 42. The first adapter plate 43 and the second adapter plate 44 can be a common flange structure for facilitating the connection and fixation of the two. The chuck 42 can adopt a three-jaw chuck 42 to facilitate the clamping and fixation of the medical bone screws.

[0072] See also Figure 5 In this embodiment, a boss 67 having the same diameter as the compression-torsion integrated sensor 41 is also designed at the bottom of the loading and mounting platform 6 to assist the torque testing module 4 in being installed to the loading center of the loading and mounting platform 6; this torque testing module 4 can be used to realize self-tapping and screw-in and screw-out testing of screws.

[0073] See also Figure 5 In this embodiment, a circular ring-shaped positioning groove 63 for installing the extraction test module 5 is also designed at the bottom of the loading and mounting platform 6. The circular ring-shaped positioning groove 63 surrounds the outer circumference of the boss 67. The outer diameter of the circular ring-shaped positioning groove 63 is consistent with the outer diameter of the extraction test tank 51. That is, the top surface of the extraction test tank 51 has a test tank groove (not shown) for accommodating the boss 67 and the torque test module installed on the boss 67. The inner diameter of the test tank groove can be larger than the outer diameter of the boss 67.

[0074] The annular positioning groove 63 is used to assist the pull-out test module 5 to be installed to the loading center designed by the loading installation platform 6; the pull-out test module 5 can be used to implement a pull-out test of a screw.

[0075] In this embodiment, the annular positioning groove 63 is also provided with an outlet 631 that matches the output signal line of the compression-twist integrated sensor 41 and can be installed with a metal waterproof connector. The outlet 631 can be used for the signal line of the compression-twist integrated sensor 41 to pass through, so that when the pull-out test module 5 is installed, the pull-out test tank 51 will not press the signal line of the compression-twist integrated sensor 41.

[0076] Furthermore, the above-mentioned loading and mounting platform 6, torque test module 4 and pull-out test module 5 can all be fixed by screw locking. The boss 67 of the loading and mounting platform 6 can be provided with a plurality of screw through holes 64 extending vertically for fixing the torque test module 4, and the circular positioning groove 63 can be provided with a plurality of mounting through holes 68 extending vertically for fixing the pull-out test module 5.

[0077] Moreover, in this embodiment, the mounting through holes 68 of the loading and mounting platform 6 and the extraction test tank 51 are unevenly distributed, for example, Figure 5 As shown, four mounting through holes 68 are provided in the circular positioning groove 63, and the connecting lines between the mounting through holes 68 form a rectangle rather than a square, so as to ensure that the pull-out test tank 51 can only be installed on the loading mounting platform 6 in a specific direction, and ensure that the signal output line of the pull-out test sensor 52 will not be hit by other moving parts.

[0078] Because the linear module 1 needs to be used for both the self-tapping test and the screw pull-out test, one of which is a small force test and the other is a large force test, the back plate of the linear module 1 away from the loading and mounting platform 6 is designed with ribs 15.

[0079] In summary, the specific working principle of the utility model is as follows:

[0080] (1) During the self-tapping test of screws, if Figure 1 As shown, the torque test module 4 is installed on the loading installation platform 6. First, a drill bit slightly larger than the inner diameter of the screw to be tested is selected to drill a hole on the standard test block. The drill bit is clamped with a chuck 42, and the standard test block is mounted on a self-centering vise 34 without an extension rod. Then, the current loop of the module motor 12 (servo motor) is controlled in the force control mode to rotate the power shaft of the module motor 12, driving the module slider 11 and the torque test module 4 in the screw rod 13 module to allow the drill bit to apply load to the standard test block, and at the same time, the rotary motor 31 (stepping motor) is rotated to achieve the drill bit drilling on the standard test block. Subsequently, during the self-tapping test of the screw, the module motor 12 is also in the force control mode to drive the screw to tap the drilled guide hole at the standard force loading rate (2±1 N / s) through the screw bit clamped in the chuck 42, while the lower rotary motor 31 rotates at the standard speed (30 r / min). The integrated compression and torque sensor 41 records real-time displacement, force, torque and other data. When the displacement and torque increase significantly, the corresponding real-time force is the self-tapping force of the screw.

[0081] (2) During the screw-in and screw-out test, if Figure 1As shown, in the force control mode of the module motor 12, the screwdriver bit held by the chuck 42 is driven to apply a standard force less than or equal to 11.5 N to the screw, and the rotary motor 31 rotates forward / reverse at a standard speed (1-5 r / min) to achieve the screwing in / out of the standard test block. In this process, the maximum torque within the specified number of turns is the corresponding screwing in / out torque.

[0082] (3) During the screw pull-out test, if Figure 2 As shown, the pull-out test module 5 is sleeved on the outside of the torque test module 4 and installed on the loading installation platform 6. During the screw pull-out test, the head of the screw that has been screwed into the standard test block is first placed in the pull-out test fixture 53. Then, the position ring of the module motor 12 (servo motor) is controlled in the position control mode to rotate the power shaft of the module motor 12, and drive the module slider 11 and the pull-out test module 5 to pull the screw out of the standard test block at a standard speed (5 mm / min). In this process, the maximum force value detected by the pull-out test sensor 52 is the pull-out force of the screw.

[0083] Again, the specific control process of the utility model is as follows:

[0084] The utility model is to realize the force control mode required for the screw self-tapping test and the screw-in and screw-out test, as well as the position control mode required for the screw pull-out test. The current loop, speed loop and position loop of the module motor 12 (servo motor) are used to control the loading of the test platform in different functional modes, and the current loop, speed loop and position loop are used in combination. Different standard force loading rates (2±1 N / s) under the screw self-tapping test function, force loading less than / equal to the standard required force value (11.5 N) under the screw screw-in and screw-out test function, and a fixed loading speed (5 mm / min) in the screw pull-out test are realized respectively.

[0085] The test platform of the utility model has both force control and displacement control modes, and can realize force loading and displacement loading of any loading rate and waveform required by the standard. Moreover, the utility model can also realize the self-attack force determination and maintenance operation required by the standard.

[0086] The above is only a preferred embodiment of the utility model, and the protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. It should be pointed out that for ordinary technicians in this technical field, equivalent changes and modifications without departing from the principle of the utility model should still fall within the protection scope of the utility model.

[0087] In the description of the embodiments of the present application, it should be understood that the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when in use, or is the orientation or position relationship commonly understood by technical personnel in this field. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0088] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" and "several" is two or more, unless otherwise clearly and specifically defined.

[0089] In the description of the embodiments of the present application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0090] In addition, the present application provides examples of various specific processes and materials, but a person skilled in the art may be aware of the application of other processes and / or the use of other materials.

Claims

1. A multifunctional medical bone screw testing platform, characterized in that: Includes load application unit and screw test fixture; The load application unit includes a linear module and a reference mounting platform; The linear module is erected on one side of the top of the reference installation platform, and the module slider of the linear module is driven by the module motor to slide back and forth in the vertical direction; The screw testing tool comprises a rotation module, a torque testing module, a pull-out testing module and a loading and mounting platform; The rotating module includes a rotating motor and a rotating adapter plate, wherein the rotating adapter plate is installed on the other side of the top of the reference mounting platform, and the rotating adapter plate is driven by the rotating motor to rotate horizontally; The loading and mounting platform is located above the rotating adapter plate and is connected and fixed to the module slider; The torque test module includes a compression-torsion integrated sensor and a chuck, and the compression-torsion integrated sensor and the chuck are sequentially installed up and down at the bottom of the loading and mounting platform; The pull-out test module includes a pull-out test tank, a pull-out test sensor and a pull-out test fixture. The pull-out test tank is detachably mounted on the bottom of the loading and mounting platform and is covered on the outer periphery of the torque test module. The pull-out test sensor and the pull-out test fixture are sequentially mounted below the pull-out test tank. The centers of the chuck, the extraction test fixture and the rotating adapter plate are located on the same vertical axis.

2. A multifunctional medical bone screw testing platform according to claim 1, characterized in that: The linear module is a linear screw module structure; The module slider is slidably matched with the screw of the linear screw module, the module motor is installed below the reference installation platform, and the power shaft of the module motor is connected to the screw through a coupling; The module motor is a servo motor.

3. A multifunctional medical bone screw testing platform according to claim 1, characterized in that: The rotating motor is installed below the reference mounting platform, and the bottom of the rotating adapter plate is installed on the reference mounting platform through an axial load-bearing bearing, and the power shaft of the rotating motor extends upward from the reference mounting platform and is connected to the rotating adapter plate. The rotating motor is a stepping motor.

4. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: A base, a first vertical plate and a second vertical plate are also provided below the reference installation platform of the load application unit; the reference installation platform is located above the base, and the first vertical plate and the second vertical plate are respectively provided on both sides between the reference installation platform and the base; The positioning design of the reference installation platform is the key to ensuring the alignment of the servo motor shaft and the linear module shaft, the alignment of the stepper motor shaft and the torque test module, and controlling the plane and horizontal plane deviation of the reference installation platform.

5. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: It also includes an installation and positioning tool; the installation and positioning tool includes a centering rod, which is detachably installed on the chuck and maintained in a vertical direction; a center hole is provided in the center of the rotating adapter plate, the inner diameter of the center hole matches the outer diameter of the centering rod, and the power shaft of the rotating motor is used to connect with the center hole.

6. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: A positioning reference groove and a positioning through hole are provided at the rear end of the loading and installation platform. The positioning reference groove is set on the top of the module slider and is locked and fixed to the top surface of the module slider through the positioning through hole by screws; a first support block and a second support block are also provided on both sides below the loading and installation platform, and the rear ends of the first support block and the second support block are connected to the front side of the module slider.

7. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: The rotary module also includes a dovetail cross slide and a self-centering vise without an extension rod; The dovetail cross slide is installed on the top of the rotating adapter plate, and the self-centering vise without extension rod is installed on the top of the dovetail cross slide.

8. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: The torque testing module also includes a first adapter plate and a second adapter plate, which are installed up and down in sequence and are located between the compression-torsion integrated sensor and the chuck; the chuck is a three-jaw chuck.

9. The multifunctional medical bone screw testing platform according to claim 1, characterized in that: The bottom of the loading and mounting platform is provided with a boss having the same diameter as the compression-torsion integrated sensor, and the boss is provided with a plurality of screw through holes extending vertically for fixing the torque test module; A circular ring-shaped positioning groove for installing the extraction test module is also provided at the bottom of the loading and mounting platform. The circular ring-shaped positioning groove surrounds the outer circumference of the boss. The outer diameter of the circular ring-shaped positioning groove is consistent with the outer diameter of the extraction test tank. A plurality of vertically penetrating installation through holes are provided in the circular ring-shaped positioning groove for fixing the extraction test module.

10. The multifunctional medical bone screw testing platform according to claim 9, characterized in that: The annular positioning groove is also provided with a wire outlet that matches the output signal wire of the compression-twist integrated sensor, and the wire outlet is used for the signal wire of the compression-twist integrated sensor to pass through; The mounting through holes in the annular positioning groove are unevenly distributed.

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