An implant fatigue testing device

Abstract

The present invention discloses an implant fatigue testing device, which belongs to the field of medical device testing technology. It includes a substrate for carrying a device body, the device body includes a vibration driving component, the vibration driving component is connected to a main vibration shaft for connecting an implant test piece, the main vibration shaft vertically penetrates the substrate, and the center of gravity of the substrate and the device body is located on the axis of the main vibration shaft. The present invention places the center of gravity of the substrate and the device body on the axis of the main vibration shaft, so that the moving trajectory of the main vibration shaft and the overall center of gravity are located in the same straight line in the vertical direction, without eccentric torque, so that the main vibration shaft runs more smoothly, avoids non-required shaking of the main vibration shaft, thereby improving the test accuracy and extending the service life of the equipment.

Description

Technical Field

[0001] The present invention relates to the technical field of medical device testing, and particularly to an implant fatigue testing device. Background Art

[0002] An implant fatigue testing device is used to perform cyclic deformation durability tests on various types of surgical implants (such as heart valves, vascular valves, vascular stents, vascular linings, occluders, etc.), aiming to provide repeated loading conditions to the test samples during operation to simulate the typical or specific physiological load conditions of artificial blood vessels or heart artificial valves or other implants over time, so as to determine the efficacy, elasticity, and wear of the device.

[0003] Taking a vascular stent as an example, the cyclic deformation durability tests related to the vascular stent include: axial tension and compression, bending, torsion, radial expansion and contraction. Among them, the bending test includes axial compression bending, mandrel bending, and non-mandrel arc bending. As Figure 1 shown, in the axial compression bending test, after the stent 1 is released in the simulated blood vessel 2, the simulated blood vessel 2 is fixed to a set of bending fixing devices 3. These bending fixing devices 3 can rotate the ends of the simulated blood vessel 2. The bending fixing devices 3 are installed on a device that can continuously transmit periodic axial motion to the simulated blood vessel 2. When the distance between the two bending fixing devices 3 shortens, the ends of the simulated blood vessel 2 will rotate, and the simulated blood vessel 2 loaded with the stent 1 will bend to a certain radius of curvature, thereby testing the axial compression bending durability of the stent 1.

[0004] However, there are still problems in how to convert the periodic axial motion of the driving device into the periodic axial motion of the bending fixing device. In particular, most implant fatigue testing devices load the device main body, such as the working unit, fixing device, etc. on the substrate, which is heavy in weight, affects vibration, and further affects the test accuracy.

[0005] The foregoing description is for the purpose of providing general background information and does not necessarily constitute prior art. Summary of the Invention

[0006] The present invention aims to provide an implant fatigue testing device to overcome the deficiencies in the prior art.

[0007] To solve the above technical problems, the technical solution of the present invention is:

[0008] An implant fatigue testing device includes a substrate for carrying the device main body. The device main body includes a vibration driving member, and the vibration driving member is connected to a main vibration shaft for connecting an implant test piece. The main vibration shaft vertically penetrates the substrate, and the center of gravity of the substrate and the device main body is located on the axis of the main vibration shaft.

[0009] Preferably, the vibration driving member is arranged on a substrate, a driving end of the vibration driving member is connected to a vibration shaft seat, a main vibration shaft is arranged on the vibration shaft seat, the vibration driving member drives the main vibration shaft to vibrate up and down through the vibration shaft seat, a cache mechanism is arranged on the side of the vibration shaft seat, the cache mechanism includes two cache springs arranged coaxially with the main vibration shaft, one cache spring is arranged above the vibration shaft seat, and the other end abuts against a positioning member, and the other cache spring is arranged below the vibration shaft seat, and the other end abuts against another positioning member.

[0010] Preferably, when the vibration drive member reaches a limit movement stroke, the buffer spring is compressed and provides an elastic force ≤ 40% of the rated continuous thrust of the vibration drive member.

[0011] Preferably, the vibration driving member is a linear motor or an electromagnetic vibrator, and the vibration driving member is vertically arranged.

[0012] Preferably, a stand for mounting a vibration driving component is provided on the base plate, and a fixed seat is also provided on the stand. The fixed seat is located below the vibration driving component, the fixed seat is slidably connected to one end of the sliding seat, and the other end of the sliding seat is connected to the driving end of the vibration driving component. A vibration shaft seat is also provided at the end where the sliding seat is connected to the fixed seat.

[0013] Preferably, a magnetic spring fixing plate is provided on the fixing seat or the standing seat, a magnetic spring is provided on the magnetic spring fixing plate, a stator of the magnetic spring is connected to the magnetic spring fixing plate, and a mover of the magnetic spring is connected to the sliding seat.

[0014] Preferably, the main vibration shaft is arranged in parallel with the driving end of the vibration driving member.

[0015] Preferably, the main vibration shaft is coaxially arranged with the driving end of the vibration driving member.

[0016] Preferably, the device body includes an upper fixing mechanism and a lower fixing mechanism, the upper fixing mechanism is connected to the bottom of the substrate, the lower fixing mechanism is connected to the main vibration axis, and the two ends of the implant test piece are respectively connected between the upper fixing mechanism and the lower fixing mechanism.

[0017] Preferably, an upper guide sleeve and a lower guide sleeve are respectively provided at both ends of the main vibration shaft, the upper guide sleeve is connected to the base plate, and the lower guide sleeve is connected to the upper fixing mechanism.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention places the center of gravity of the substrate and the equipment body on the axis of the main vibration shaft so that the moving trajectory of the main vibration shaft and the overall center of gravity are in the same straight line in the vertical direction without eccentric torque, thereby making the main vibration shaft run more smoothly and avoiding unnecessary shaking of the main vibration shaft, thereby improving test accuracy and extending the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 Schematic diagram of the axial compression and bending test of the vascular stent in the prior art;

[0022] Figure 2 Stereo enlarged schematic diagram of the implant fatigue test device of the present invention in Embodiment 1;

[0023] Figure 3 Explosion schematic diagram of the casing of the present invention in Embodiment 1;

[0024] Figure 4 Schematic diagram of the structure of the working unit of the present invention in Embodiment 1;

[0025] Figure 5 Schematic diagram of the structure of the vibration driving member of the present invention in Embodiment 1;

[0026] Figure 6 Another schematic diagram of the structure of the vibration driving member of the present invention;

[0027] Figure 7 Schematic diagram of the structure of the lifting driving member and the elevator of the present invention in Embodiment 1;

[0028] Figure 8 Schematic diagram of the structure of the clamping mechanism of the elevator of the present invention in Embodiment 1;

[0029] Figure 9 Schematic diagram of the structure of the clamping seat of the present invention in Embodiment 1;

[0030] Figure 10 Explosion schematic diagram of the base of the present invention in Embodiment 1;

[0031] Figure 11 Stereo enlarged schematic diagram of the test fixing device of the present invention in Embodiment 1;

[0032] Figure 12 Schematic diagram of the structure of the force value sensor and its fixture of the present invention in Embodiment 1;

[0033] Figure 13 Explosion schematic diagram of the force value sensor and its fixture of the present invention in Embodiment 1;

[0034] Figure 14 Stereo magnified schematic view of the implant fatigue testing device of the present invention in Embodiment 2;

[0035] Figure 15 Another angle stereo magnified schematic view of the implant fatigue testing device of the present invention in Embodiment 2;

[0036] Figure 16 Cross-sectional schematic view of the implant fatigue testing device of the present invention in Embodiment 2.

[0037] Specifically, 1. Bracket; 2. Simulated blood vessel; 3. Bending fixing device;

[0038] 100. Machine housing; 110. Front cover frame; 111. Front cover plate; 120. Rear cover frame; 121. Rear cover plate; 130. Upper left side beam; 131. Left cover plate; 1311. Left ventilation area; 140. Upper right side beam; 141. Right cover plate; 1411. Right ventilation area; 151. Upper cover plate; 152. Drag chain seat plate;

[0039] 200. Substrate; 210. Adapter flange;

[0040] 300. Main guiding column; 301. Hoisting ring hole; 310. Support plate; 320. Main guiding sliding sleeve; 330. Locking nut; 331. Flat washer; 332. Wave washer;

[0041] 400. Base; 410. Bottom plate; 420. Wire passing seat; 421. Electrical interface box; 422. Male head seat; 430. Rubber pad; 440. Auxiliary beam; 441. Groove;

[0042] 500. Vibration driving member; 501. Standing seat; 502. Fixed seat; 503. Sliding seat; 504. Magnetic spring fixing plate; 505. Vibration shaft seat;

[0043] 510. Main vibration shaft; 511. Upper guiding sliding sleeve; 512. Lower guiding sliding sleeve;

[0044] 520. Buffer spring; 521. Guide post; 522. Positioning member;

[0045] 600. Lifting driving member; 610. Lift; 611. Lead screw; 620. Clamping mechanism; 621. Clamping seat; 6211. Machine installation groove; 6212. Clamping block I; 6213. Clamping block II; 6214. Clamping hole; 6215. Buffer groove I; 6216. Buffer groove II; 6217. Fastening hole; 622. Top cover;

[0046] 700. Controller;

[0047] 800, Upper fixing mechanism; 801, Hanging rack plate I; 802, Hanging rack plate II; 803, Hanging rack plate III; 810, Force value sensor; 811, Slide column; 8111, Threaded section; 812, Adjusting nut; 813, Mounting seat; 8131, Connecting hole; 820, Lower fixing mechanism; 821, Auxiliary vibration shaft; 822, Lower fixture

[0048] 900, Environmental simulation chamber; 910, Top plate Specific implementation mode

[0049] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention

[0050] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation on the protection scope of the present invention. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more

[0051] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" 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 or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific situations

[0052] Embodiment 1:

[0053] As Figure 2As shown in the figure, an implant fatigue testing device includes a device main body, and the device main body includes a working unit. The working unit is installed in a housing 100 on a substrate 200. A upper fixing mechanism 800 is connected below the substrate 200. A lower fixing mechanism 820 is arranged below the upper fixing mechanism 800, and the lower fixing mechanism 820 is connected to the working unit. An implant test piece is clamped between the upper fixing mechanism 800 and the lower fixing mechanism 820. The working unit drives the lower fixing mechanism 820 to vibrate up and down relative to the upper fixing mechanism 800 to realize the test of the implant test piece. The substrate 200 is suspended above a base 400 through two main guiding columns 300 and a lead screw 611 respectively arranged on both sides thereof, providing space for the installation of the upper fixing mechanism 800 and the lower fixing mechanism 820.

[0054] As Figure 3 shown, the housing 100 adopts a modular splicing structure, so that it can be selectively disassembled according to maintenance requirements without overall disassembly. Specifically, the housing 100 includes a front cover frame 110 and a rear cover frame 120 which are oppositely arranged. The front cover frame 110, the rear cover frame 120 and the substrate 200 are all detachably connected by screws. A left upper side beam 130 and a right upper side beam 140 are detachably arranged between the front cover frame 110 and the rear cover frame 120 by screws. The housing 100 forms a frame main body structure through the front cover frame 110, the rear cover frame 120, the left upper side beam 130 and the right upper side beam 140. And a front cover plate 111, a rear cover plate 121, a left cover plate 131, a right cover plate 141 and an upper cover plate 151 are detachably connected to the frame main body structure by screws, so that each cover plate and the front cover frame 110, the rear cover frame 120, the left upper side beam 130 and the right upper side beam 140 can be disassembled separately, and thus can be selectively disassembled according to maintenance requirements, enabling maintenance personnel to maintain the corresponding working machine inside it without overall disassembly. And through the frame structure with greater strength, the housing 100 of this device is stable. At the same time, relatively speaking, the cover plates can adopt thin plates, so that the housing 100 is lighter in weight.

[0055] Generally speaking, the cover plate adopts a connection method of being embedded in the frame main structure, so as to make the surface of the casing 100 as flat as possible, and the working machine that needs to be frequently maintained is installed close to the front cover plate 111. Therefore, only the front cover plate 111 needs to be disassembled during routine maintenance. To further facilitate disassembly, through threaded holes are provided at the bottom and top of the front cover frame 110 for screws to pass through and be connected to the bottom and top of the front cover plate 111 respectively. The two threaded holes are coaxially and oppositely arranged. During installation, first, the bottom of the front cover frame 110 is fixed to the substrate 200 by screws, then the front cover plate 111 is embedded into the front cover frame 110, and then the screws pass through the top of the front cover frame 110 and are connected to the top of the front cover plate 111, and the screws pass through the bottom of the front cover frame 110 and are connected to the bottom of the front cover plate 111. Thus, the front cover plate 111 is fixed inside the front cover frame 110 through its upper and lower sides, which is convenient for disassembly and assembly. And when the screws become loose due to vibration, the upper screws can stay in the holes like pins due to gravity and will not fall off, thereby improving the safety of the equipment. For the remaining cover plates, such as the rear cover plate 121, the left cover plate 131, the right cover plate 141, and the upper cover plate 151, their edges are connected to the frame main structure by screws. Left ventilation areas 1311 and right ventilation areas 1411 are respectively provided on the left cover plate 131 and the right cover plate 141. The left ventilation areas 1311 and the right ventilation areas 1411 are diagonally distributed, so as to facilitate air flow through the entire interior of the casing 100 and achieve uniform heat dissipation.

[0056] The working unit is arranged on the substrate 200 and is covered inside the casing 100. In this embodiment, as Figure 4 shown, the working unit includes a vibration driving member 500 and its transmission assembly. The vibration driving member 500 provides power for the relative movement of the upper fixing mechanism 800 and the lower fixing mechanism 820. The working unit further includes a lifting driving member 600 and its transmission assembly. The lifting driving member 600 provides power for the lifting of the substrate 200, so as to adjust the height positions of the upper fixing mechanism 800 and the lower fixing mechanism 820. The working unit may further include a controller 700, and the controller 700 is connected to the vibration driving member 500 and the lifting driving member 600 to control the operations of both.

[0057] The vibration driving member 500 of the present device is connected with a main vibration shaft 510. The main vibration shaft 510 is arranged vertically through the substrate 200, and the upper fixing mechanism 800 is fixed to the substrate 200, and the lower fixing mechanism 820 is connected to the main vibration shaft 510. The vibration driving member 500 drives the main vibration shaft 510 to vibrate up and down, thereby driving the lower fixing mechanism 820 to vibrate up and down relative to the upper fixing mechanism 800. The vibration driving member 500 can be a linear motor or an electromagnetic vibrator, a magnetostrictive vibrator, an electric or non-electric mechanical vibration device, etc., preferably a voice coil motor. The proximal end of the main vibration shaft 510 is sleeved with an upper guide sleeve 511, and the distal end is sleeved with a lower guide sleeve 512. Through double-point support, the stability and axial retention of the main vibration shaft 510 moving up and down are improved. Specifically, the upper guide sleeve 511 is fixed to the substrate 200, and the lower guide sleeve 512 is fixed to the upper fixing mechanism 800.

[0058] In order to ensure the smooth operation of the main vibration shaft 510, the center of gravity of the substrate 200 and the device body is located on the axis of the main vibration shaft 510, that is, the substrate 200 and the device body as a whole have their center of gravity located on the axis of the main vibration shaft 510, and the moving trajectory of the main vibration shaft 510 is in the same straight line as the overall center of gravity in the vertical direction, without eccentric torque, thereby making the main vibration shaft 510 run more smoothly and avoiding unnecessary shaking of the main vibration shaft 510, thereby improving the test accuracy and extending the service life of the equipment.

[0059] like Figure 5 As shown, in this embodiment, the vibration driving member 500 is arranged vertically, that is, perpendicular to the base plate 200, which reduces the occupied area, reduces the transmission components, and improves the space utilization rate of the equipment. In order to install the vibration driving member 500, a stand 501 is arranged on the base plate 200, and the stand 501 includes a back plate arranged perpendicular to the base plate 200, and an upper plate is arranged horizontally on the top of the back plate. The vibration driving member 500 is fixed to the upper plate, and the driving end faces downward. Ribs are also arranged on both sides of the stand 501 to improve the overall strength, thereby improving the stability of the operation of the vibration driving member 500.

[0060] The driving end of the vibration driving member 500 is connected to a vibration shaft seat 505, and the vibration shaft seat 505 is connected to the main vibration shaft 510. The main vibration shaft 510 penetrates the substrate 200 and is connected to the lower fixing mechanism 820. A fixing seat 502 is also provided on the stand 501, and a slide seat 503 slidably connected to the fixing seat 502 is connected to the driving end of the vibration driving member 500, and the vibration shaft seat 505 is provided on the slide seat 503, so that the vibration driving member 500 drives the main vibration shaft 510 to move up and down stably, thereby improving the stability of the periodic axial motion of the main vibration shaft 510, and thus improving the test accuracy.

[0061] In this embodiment, the fixed seat 502 is located directly below the vibration driving member 500. The sliding seat 503 is adopted. One end of the sliding seat 503 is connected to the driving end, and the other end is connected to the vibration shaft seat 505, so that the sliding seat 503 can be as thin as possible, thereby reducing the load on the driving end and improving the running stability of the vibration driving member 500. At the same time, this setting makes the driving end of the main vibration shaft 510 and the vibration driving member 500 arranged in parallel, that is, the vibration shaft driving member, the main vibration shaft 510 and the buffer mechanism are arranged side by side in sequence, which is convenient for maintaining different components, and multiple components are horizontally arranged in sequence, which is beneficial to reducing the height of the device.

[0062] A cross track 507 can be provided between the sliding seat 503 and the fixed seat 502. The cross track 507 is also called a cross roller track or a cross roller column track. One track of the cross track 507 is arranged on the sliding seat 503, and the other track is arranged on the fixed seat 502, thereby improving the reciprocating linear motion accuracy of the sliding seat 503, and further improving the test accuracy. And in this embodiment, convex ribs are provided on the side surface of the fixed seat 502, and one track of the cross track 507 is provided on both sides of the convex ribs. The corresponding surface of the sliding seat 503 is provided with grooves, and the other track of the cross track 507 is provided on both sides of the grooves, so as to realize bilateral sliding, improve the reciprocating linear motion accuracy of the sliding seat 503, improve the strength of the connection between the two, improve the motion stability, and further improve the test accuracy.

[0063] A magnetic spring fixing plate 504 is also provided on the fixed seat 502 or the vertical seat 501. In this embodiment, the magnetic spring fixing plate 504 is arranged on the fixed seat 502. A magnetic spring is arranged on the magnetic spring fixing plate 504. The stator of the magnetic spring is connected to the magnetic spring fixing plate 504, and the mover of the magnetic spring is connected to the sliding seat 503. The magnetic spring pulls the sliding seat 503, so that the load on the driving end of the vibration driving member 500 is close to zero. When the vibration driving member 500 vibrates, the load force deviation caused by gravity can be reduced as much as possible within the upper and lower two vibration cycles, thereby improving the running accuracy of the vibration driving member 500 and extending the service life of the vibration driving member 500.

[0064] The magnetic spring in this device can adopt the magnetic spring in the prior art, such as the M-Spring constant force magnetic spring, which provides a constant thrust or pull force within the entire stroke range of the vibration driving member 500, and realizes the compensation or cancellation of gravity through the magnetic field.

[0065] The buffer mechanism is arranged on the side of the vibration shaft seat 505, and 1, 2 or more can be provided. In this embodiment, one buffer mechanism is provided, and it is arranged at the other end of the vibration shaft seat 505 relative to the vibration driving member 500, and is basically symmetrically arranged about the main vibration shaft 510 and the vibration driving member 500.

[0066] The buffer mechanism includes two buffer springs 520 coaxially arranged with the main vibration shaft 510. One buffer spring 520 is arranged above the vibration shaft seat 505, with its bottom end abutting against the vibration shaft seat 505 and its top end abutting against the positioning member 522 located above the vibration shaft seat 505. The other buffer spring 520 is arranged below the vibration shaft seat 505, with its top end abutting against the vibration shaft seat 505 and its bottom end abutting against the positioning member 522 located below the vibration shaft seat 505.

[0067] The buffer springs 520 can provide supporting force or pulling force for the vibration shaft seat 505, the main vibration shaft 510 and its load, such as a fixing device, so as to reduce the load on the driving end of the vibration driving member 500 and extend the service life of the vibration driving member 500. Preferably, the two buffer springs 520 are provided with a pre-compression amount, so as to provide a certain elastic force to offset the load on the driving end of the vibration driving member 500 and improve the running stability of the two buffer springs 520 at the same time. Moreover, the two buffer springs 520 respectively have a downward thrust and an upward thrust on the vibration shaft seat 505, and there will be an automatic force balance position when the vibration driving member 500 is not powered on or the vibration driving member 500 does not output driving force. Therefore, on the one hand, after the vibration driving member 500 is powered off, the main vibration shaft 510 can automatically return to the force balance point; on the other hand, during the vibration process, every time the main vibration shaft 510 is at the maximum displacement from the balance point (that is, the real starting point), for example, when vibrating upward to the maximum displacement, at this time the upper buffer spring 520 has the largest compression amount, and the compression amount of the upper buffer spring 520 is greater than that of the lower one. Therefore, the resultant force of the upper and lower buffer springs 520 is downward, and at this time the vibration driving member 500 needs to provide a downward driving force to drive the main vibration shaft 510 to move downward. At this time, the internal stress of the buffer spring 520 will save a part of the downward driving force for the vibration driving member 500, which is beneficial to the long-term stable operation of the vibration driving member 500 and the improvement of the service life of the driving circuit of the vibration driving member 500.

[0068] Preferably, when the vibration driving member 500 reaches the limit movement stroke, the buffer spring 520 is compressed and the provided elastic force ≤ 40% of the rated continuous thrust of the vibration driving member 500. If the compression and rebound force of the buffer spring 520 is too large, it will also increase the load when the vibration driving member 500 is pushed to the limit position, so it is recommended not to be greater than 40%.

[0069] In this embodiment, the buffer mechanism further includes a guide post 521 arranged on the substrate 200. The buffer spring 520 is sleeved on the guide post 521. Both positioning members 522 are annular blocks, sleeved on the guide post 521 and fixed to it. The internal gap between the guide post 521 and the buffer spring 520 is not less than 1 mm to avoid contact and friction between the buffer spring 520 and the guide post 521 after compression, and at the same time not greater than 5 mm to improve the space utilization rate.

[0070] The device is connected to the vibration shaft seat 505 through the driving end of the vibration driving member 500. The vibration shaft seat 505 is connected to the main vibration shaft 510 and the buffer mechanism. The buffer mechanism includes a buffer spring 520 arranged coaxially with the main vibration shaft 510. By means of the buffer spring 520, the load on the driving end of the vibration driving member 500 is further reduced, the service life of the vibration driving member 500 is prolonged, and the vibration driving member 500 is kept balanced, so that the main vibration shaft 510 drives the implant test piece to vibrate up and down at the balance point, improving the stability of the periodic axial movement of the main vibration shaft 510, and further improving the test accuracy.

[0071] As Figure 6 shown, it is another connection structure of the vibration driving member 500 and the main vibration shaft 510 of the device. In this structure, the main vibration shaft 510 is arranged coaxially with the driving end of the vibration driving member 500, so as to avoid the generation of bending moment, improve the load capacity of the main vibration shaft 510, and improve the stability of the periodic axial movement of the main vibration shaft 510, and further improve the test accuracy.

[0072] A cantilever beam is arranged in the radial direction of the main vibration shaft 510, and a buffer mechanism is arranged on the cantilever beam. Preferably, two buffer mechanisms are symmetrically arranged.

[0073] As Figure 7 shown, the lifting driving member 600 is vertically arranged on the substrate 200. The lifting driving member 600 provides power for the lifting of the substrate 200, so as to adjust the height positions of the upper fixing mechanism 800 and the lower fixing mechanism 820. The transmission assembly at least includes a T-shaped coupling, so that the power of the lifting driving member 600 is evenly transmitted to both sides, so that the substrate 200 remains flat in any state, and further provides a basis for the assembly of other components in place, improving the stiffness of the whole machine, realizing good locking, and further improving the vibration stability. The lifting driving member 600 can be a servo motor, a stepping motor, etc., and it is connected to the elevator 610 through the transmission assembly. The device adopts a screw elevator. The screw 611 is arranged parallel to the main guiding column 300 and fixed on the base 400. The elevator 610 is arranged on the substrate 200, that is, the screw 611 is fixed and the nut inside the elevator 610 rotates to drive the substrate 200 to move up and down. The top ends of the screw 611 and the main guiding column 300 are connected with a support plate 310, so that the screw 611 and the main guiding column 300 become an integral body with better rigidity, improving the stability of the support for the substrate 200.

[0074] At this time, the substrate 200 and the working unit thereon are relatively fixed by the thread engagement of the screw 611 and the nut. To further improve the stability of the substrate 200 and prevent the substrate 200 from falling, the elevator 610 realizes a clamping effect with the main guiding column 300 through the clamping mechanism 620. Specifically, as Figure 8As shown, the clamping mechanism 620 includes a clamping base 621 and a top cover 622. Except that the elevator 610 is fixed to the substrate 200, the clamping base 621 is also fixed to the substrate 200. The elevator 610 is arranged inside the clamping base 621, and a top cover 622 is arranged above the clamping base 621 to achieve dust prevention. As Figure 9 shown, the clamping base 621 includes a machine mounting part and a column mounting part arranged side by side. The machine mounting part is provided with a machine mounting groove 6211, and the elevator 610 is clamped in the machine mounting groove 6211. An avoidance opening is arranged on one side of the machine mounting groove 6211 facing the coupling. The column mounting part includes a clamping block I 6212 and a clamping block II 6213. From left to right, the clamping base 621 is successively a machine mounting part, a clamping block I 6212, and a clamping block II 6213, and the three have a compact structure. Arc grooves are arranged on the opposite sides of the clamping block I 6212 and the clamping block II 6213 to form a clamping hole 6214 for holding the main guiding column 300. The clamping block I 6212 and the clamping block II 6213 are connected at one end, and there is a distance between the other ends of the two, so that the size of the clamping hole 6214 can be adjusted. The clamping block II 6213 is provided with a fastening hole 6217 facing the clamping block I 6212 for a screw to pass through and lock the clamping block I 6212 and the clamping block II 6213, so that the clamping block I 6212 and the clamping block II 6213 clamp the main guiding column 300. Furthermore, on the basis that the lead screw 611 fixes the substrate 200, the clamping base 621 clamps the main guiding column 300 to achieve the purpose of fixing the substrate 200, improve the stability of the substrate 200, and reduce vibration. To avoid excessive deformation and fracture of the connection ends of the clamping block I 6212 and the clamping block II 6213 caused by screw fastening, a buffer groove I 6215 is opened on the outer side of the connection ends of the two, and the buffer groove I 6215 runs through the height direction of the connection ends. A buffer groove II 6216 is also opened on the inner side of the connection ends of the two, and the buffer groove II 6216 runs through the height direction of the connection ends. When the clamping block II 6213 deforms towards the clamping block I 6212 under the action of the screw, the arc groove of the clamping block II 6213 deforms more uniformly towards the arc groove of the clamping block I 6212, so as to ensure the contact area with the main guiding column 300, and further improve the clamping stability of the main guiding column 300. The connection ends of the clamping block I 6212 and the clamping block II 6213, that is, the area clamped by the buffer groove I 6215 and the buffer groove II 6216, have a strength that can support the total gravity of the entire substrate 200 and the equipment main body connected thereto, so as to prevent the substrate 200 and the equipment main body from falling due to gravity and causing accidents after two elevators or the lifting driving parts 600 fail and cannot provide support force. In this embodiment, there are two groups of clamping bases 621 arranged left and right. Therefore, the strength of the connection ends of a group of clamping block I 6212 and clamping block II 6213 ≥ 1 / 2 of the gravity of the substrate 200 and the equipment main body. Further, there is an interference amount of about 20% to ensure a sufficient safety factor.

[0075] During use, the substrate 200 is moved to a specified position by the elevator 610, and then the main guiding column 300 is clamped by the clamping seat 621, so that the test environment is more stable. When the elevator 610 works, the main guiding column 300 provides lifting guidance for the elevator 610 at the same time. A main guiding sliding sleeve 320 is also arranged on the substrate 200. The main guiding sliding sleeve 320 is sleeved on the outside of the main guiding column 300. The material of the main guiding sliding sleeve 320 is engineering plastic. By using the high strength, fatigue resistance, wear resistance, self-lubrication and shock absorption characteristics of the engineering plastic, the stability of the movement of the substrate 200 is improved. And the length of the main guiding sliding sleeve 320 in this equipment is 1 / 7 - 1 / 5 of the length of the main guiding column 300, so as to fully ensure the contact area between the main guiding sliding sleeve 320 and the main guiding column 300. And under the same contact surface gap in the vertical direction, the deviation of the vector direction of the main guiding column 300 along the axial direction of the main guiding sliding sleeve 320 is small, thus improving its movement stability and heavy load retention.

[0076] To make the substrate 200 more stable when the clamping seat 621 clamps the main guiding column 300, two main guiding columns 300 are provided, and the two main guiding columns 300 are symmetrically arranged about the main vibration axis 510. A lifting ring hole 301 can also be arranged at the top of the main guiding column 300 for installing a lifting ring, so that the equipment can be transferred by hoisting.

[0077] Such as Figure 10As shown in the figure, the main guiding column 300 and the lead screw 611 are connected to the base 400. The base 400 includes a bottom plate 410. The lead screw 611 is fixed to the bottom plate 410 through a flange. The main guiding column 300 passes through the bottom plate 410 and is connected with a locking nut 330. A flat washer 331 and a corrugated washer 332 are arranged between the locking nut 330 and the bottom plate 410. The flat washer 331 is used to increase the contact surface area between the locking nut 330 and the main guiding column 300, reduce the pressure per unit area, and protect the surfaces of both from being damaged. The corrugated washer 332 is used to prevent the locking nut 330 from loosening and slow down the impact. Further, the bottom end of the main guiding column 300 is stepped, so as to be pressed against the bottom plate 410 through the stepped shaft section and locked by the locking nut 330. In this embodiment, the radial constraint of the main guiding column 300 is realized through a light hole, that is, a through hole with a smooth inner wall, to improve the verticality during installation. Moreover, the machining accuracy of the light hole is much higher than that of the threaded hole, and the hole position accuracy is high, so as to ensure the verticality of the main guiding column 300 before installation. In addition, the bottom plate 410 is generally made of aluminum alloy, and the main guiding column 300 and the locking nut 330 are made of steel. Aluminum alloy is relatively softer than steel. If coarse-threaded screws are used to ensure mechanical strength during machining of threads, they are likely to loosen during vibration. While using a steel nut with high hardness and high strength, fine-threaded screws can be used, which can achieve a good self-locking and anti-loosening effect under the condition of meeting the strength requirements.

[0078] The main guiding column 300 and the base 400, that is, the end connected to the bottom plate 410, is provided with an annular groove. The side surface of the bottom plate 410 is provided with a column locking hole facing the annular groove. The column locking hole is communicated with the light hole. By installing a bolt to abut against the bottom of the annular groove located in the light hole, the radial fixation of the main guiding column 300 is realized, further improving the stability of the main guiding column 300 and the stability of the lifting bracket.

[0079] Below the bottom plate 410, two auxiliary beams 440 are symmetrically arranged. The two auxiliary beams 440 are respectively arranged directly below the two side lead screws 611 and the main guiding columns 300, so as to improve the stability of the equipment support and reduce the contact area between the equipment and the ground, thereby reducing vibration conduction and avoiding affecting other equipment in the laboratory. Further, to prevent the locking nut 330 from loosening and falling off, a groove 441 is arranged above the auxiliary beam 440. After the locking nut 330 locks the main guiding column 300, it is embedded in the groove 441. The depth of the groove 441 is adapted to the thickness of the locking nut 330 to prevent the locking nut 330 from detaching from the main guiding column 300, that is, the gap between the bottom surface of the groove 441 and the locking nut 330 is not enough to allow the locking nut 330 to detach from the main guiding column 300, restricting the falling off of the locking nut 330, thereby improving the stability and safety of the equipment. Shock-absorbing feet or shock-absorbing rubber pads 430 can also be arranged below the two ends of the auxiliary beam 440. For further shock absorption, a rubber pad 430 is also laid on the upper surface of the bottom plate 410. The rubber pad 430 covers the entire bottom plate 410 and fits the edges of the lead screw 611 and the main guiding column 300, so as to absorb the vibration conducted by the two.

[0080] The working unit cables of this equipment extend out from the top end of the machine shell 100 and are connected to the electrical interface box arranged on the base 400. As Figure 2 and Figure 3 shown, through holes are opened at the edge of the upper cover plate 151 of the machine shell 100 for the cables of the working unit to extend out, and a drag chain seat plate 152 is installed at the through hole, so that the cables between the machine shell 100 and the electrical interface box are arranged through the drag chain. As Figure 10 shown, at the position of the bottom plate 410 corresponding to the drag chain seat plate 152, a wire passing seat 420 is arranged. An electrical interface box 421 and a corresponding male head seat 422 are installed on the wire passing seat 420, so that the cables move synchronously with the lifting of the elevator 610, avoiding cable chaos.

[0081] As Figure 11 shown, an upper fixing mechanism 800 and a lower fixing mechanism 820 are arranged below the substrate 200. The upper fixing mechanism 800 is connected to the substrate 200 through a transfer flange 210, so as to facilitate the replacement of the upper fixing mechanism 800 according to different test types and the types of implant test pieces. The lower fixing mechanism 820 is connected to the main vibration shaft 510 passing through the substrate 200 and the upper fixing mechanism 800 through a flange. The main vibration shaft 510 drives the lower fixing mechanism 820 to vibrate up and down relative to the upper fixing mechanism 800, so as to test the implant test piece. A force sensor 810 is also arranged on the upper fixing mechanism 800. The two ends of the implant test piece are respectively connected to the force sensor 810 and the lower fixing mechanism 820, so as to detect its force condition.

[0082] The upper fixing mechanism 800 includes a hanging plate I 801 and a hanging plate II 802 connected in sequence from top to bottom. The hanging plate I 801 is connected to the adapter flange 210. The main vibration shaft 510 passes through the hanging plate I 801 and the hanging plate II 802. The force value sensor 810 is arranged below the hanging plate II 802 through the mounting seat 813. As Figure 12 and Figure 13 shown, the sliding column 811 passes through the disk body of the hanging plate I 801 and the disk body of the hanging plate II 802. The bottom end of the sliding column 811 is connected to the mounting seat 813. A threaded section 8111 is arranged on the sliding column 811 between the disk body of the hanging plate I 801 and the disk body of the hanging plate II 802, and an adjusting nut 812 is sleeved on the outside thereof. By rotating the adjusting nut 812, the sliding column 811 drives the force value sensor 810 to move up and down, so as to adjust the distance between the upper fixing mechanism 800 and the lower fixing mechanism 820, and further make the initial force on the implant test piece located between the two be 0, which is convenient for unified testing. Further, a sliding column locking hole is arranged on the side of the disk body of the hanging plate II 802 facing the side of the sliding column 811 for a bolt to abut and lock the sliding column 811. A connection hole 8131 is opened on the side of the mounting seat 813 for a screw to pass through so that the mounting seat 813 is connected to the sliding column 811. Still further, the corresponding position of the sliding column 811 is a planar structure, so as to facilitate the end face of the bolt to abut and lock.

[0083] The lower fixing mechanism 820 includes a sub-vibration shaft 821 detachably connected to the main vibration shaft 510. A lower clamp 822 is connected to the tail end of the sub-vibration shaft 821. The lower clamp 822 is selected according to the type of the implant test piece.

[0084] Embodiment 2:

[0085] On the basis of Embodiment 1, as Figures 14 - 15 shown, in Embodiment 2, the device is further provided with an environment simulation box 900 to simulate the actual environment where the implant test piece is located and improve the test accuracy. As Figure 16 shown, the sectional view of the device, the basic structure of the device is the same as that of Embodiment 1.

[0086] The environment simulation box 900 can be a water tank or an air box, so as to provide a set test environment with a certain temperature, pressure, etc. for the implant test piece. During test preparation, the implant test piece located between the upper fixing mechanism 800 and the lower fixing mechanism 820 is moved into the environment simulation box 900 through the elevator 610.

[0087] The environmental simulation chamber 900 is arranged on the base 400. Specifically, the rubber pad 430 is cut with an avoidance area adapted to the bottom surface of the environmental simulation chamber 900. A backing plate is embedded in the avoidance area. The backing plate is generally made of a metal part. The backing plate is connected to the bottom plate 410 to carry and fix the environmental simulation chamber 900. Multiple threaded mounting holes can be preset on the backing plate to facilitate the subsequent replacement of environmental simulation chambers 900 or other structural parts of different sizes. Flanking plates are arranged on the sides of the environmental simulation chamber 900 and are used to connect to the backing plate. The environmental simulation chamber 900 includes a top plate 910, which is used to close the chamber during testing to prevent sundries from falling in and interfering with the test accuracy. And, taking the water tank as an example, the top plate 910 can reduce the risk of water splashing out and also reduce the impact of water evaporation on the test. The top plate 910 is arranged on the upper fixing mechanism 800. Specifically, a hanging plate III 803 (refer to Figure 11 ) is arranged below the hanging plate II 802. The top plate 910 is connected to the hanging plate III 803, so that the environmental simulation chamber 900 can be opened and closed through the upper fixing mechanism 800. The front and rear panels of the environmental simulation chamber 900 are set to be detachable, so that the implant test piece can be replaced or the implant test piece can be inspected by disassembling the front and rear panels of the environmental simulation chamber 900 without adjusting the height of the substrate 200.

[0088] In this embodiment, the electrical interface box 421 is arranged at a certain distance from the bottom plate 410. Correspondingly, the lowermost male socket 422 is also arranged at a certain distance from the bottom plate 410, such as 20 - 30 mm, so as to prevent the liquid from flooding the electrical interface and causing equipment damage when the environmental simulation chamber 900, especially the water tank, is broken.

[0089] In addition, it should be understood that although this specification is described according to the embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An implant fatigue testing device, characterized in that, it includes a substrate for carrying the device main body. The device main body includes a vibration driving member, and the vibration driving member is connected with a main vibration shaft for connecting an implant test piece. The main vibration shaft vertically penetrates the substrate, and the center of gravity of the substrate and the device main body is located on the axis of the main vibration shaft; The vibration driving member is arranged on the substrate. The driving end of the vibration driving member is connected with a vibration shaft seat, and the main vibration shaft is arranged on the vibration shaft seat. The vibration driving member drives the main vibration shaft to vibrate up and down through the vibration shaft seat. A buffer mechanism is arranged on the side of the vibration shaft seat. The buffer mechanism includes two buffer springs arranged coaxially with the main vibration shaft. One buffer spring is arranged above the vibration shaft seat and the other end abuts against a positioning member. The other buffer spring is arranged below the vibration shaft seat and the other end abuts against another positioning member; The two buffer springs are provided with a pre-compression amount and are used to offset the load at the driving end of the vibration driving member; The vibration driving member is a linear motor or an electromagnetic vibrator, and the vibration driving member is arranged vertically; The main vibration shaft is arranged parallel to the driving end of the vibration driving member; The device main body includes an upper fixing mechanism and a lower fixing mechanism. The upper fixing mechanism is connected below the substrate, the lower fixing mechanism is connected with the main vibration shaft, and the two ends of the implant test piece are respectively connected between the upper fixing mechanism and the lower fixing mechanism; Upper guiding sliding sleeves and lower guiding sliding sleeves are respectively arranged at both ends of the main vibration shaft. The upper guiding sliding sleeve is connected with the substrate, and the lower guiding sliding sleeve is connected with the upper fixing mechanism; A vertical seat for installing the vibration driving member is arranged on the substrate. A fixing seat is also arranged on the vertical seat. The fixing seat is located below the vibration driving member. One end of the sliding seat is slidably connected with the fixing seat, and the other end of the sliding seat is connected with the driving end of the vibration driving member. A vibration shaft seat is also arranged at the end of the sliding seat connected with the fixing seat; A magnetic spring fixing plate is arranged on the fixing seat or the vertical seat. A magnetic spring is arranged on the magnetic spring fixing plate. The stator of the magnetic spring is connected with the magnetic spring fixing plate, and the mover of the magnetic spring is connected with the sliding seat.

2. The implant fatigue testing device according to claim 1, characterized in that, when the vibration driving member reaches the limit movement stroke, the buffer spring is compressed and the provided elastic force ≤ 40% of the rated continuous thrust of the vibration driving member.

Images