Tensile and torsional fatigue testing device for tracheal stent

Abstract

The utility model relates to an air pipe support stretching torsion fatigue testing device which comprises a workbench arranged at the bottommost part, a linear module is vertically and fixedly installed on one side of the upper surface of the workbench, an air pipe support clamp and a rotating device are installed on the linear module, and the air pipe support clamp is composed of an upper clamp and a lower clamp which are the same in structure. An air pipe clamp perpendicularly placed between the upper clamp and the lower clamp is fixedly clamped through the upper clamp and the lower clamp, the upper clamp is connected with a micro air pump installed beside the linear module, and the lower clamp is installed on a rotating device and driven by the rotating device. The tensile torsional fatigue testing device can be used for carrying out tensile torsional fatigue testing on tracheal stents with different sizes, and clamping of the tracheal stents is completed through the horizontal pushing type clamp and the silica gel hose together, so that deformation of the stents is reduced, and the precision of a testing result is further improved. According to the utility model, the fatigue life of the tracheal stent is determined by simulating the real service condition in the tracheal stent, and the test reliability is ensured.

Description

Technical Field

[0001] The utility model relates to a testing device, in particular to a tracheal stent tensile torsion fatigue testing device, belonging to the technical field of instrument testing. Background Art

[0002] With the continuous development of medical technology, many diseases can be treated with good treatment methods. However, in modern clinical medical practice, tracheal-related diseases are still a type of lesion that often threatens life and requires active interventional treatment. Tracheal-related diseases range from congenital dysplasia, infection and inflammation, traumatic injury to invasion of the trachea itself and surrounding tumors. These lesions can eventually lead to tracheal stenosis and further cause respiratory distress, often endangering the patient's life. Doctors often use "end-to-end anastomosis after resection of the lesion segment" to treat airway stenosis lesions, but if the lesion segment ranges more than 50% (about 6cm) in adults or more than 30% in children, simple end-to-end anastomosis will increase the tension of the anastomosis and cause severe postoperative anastomotic tearing. Therefore, a tracheal stent must be placed during the operation to reconstruct the continuity of the trachea and maintain airway patency.

[0003] However, due to the different movement modes of various parts of the human body, the loads on the tracheal stent in the body are very complex. For example, the twisting, tilting and lowering of the head in daily life cause different stress conditions on the trachea. Therefore, it is particularly important to evaluate the service life of the tracheal stent, and the service life of the tracheal stent is mainly affected by the tensile fatigue performance and torsional fatigue performance of the tracheal stent. Therefore, a tracheal stent tensile torsional fatigue test device is urgently needed to evaluate the service life of the tracheal stent in the human body through in vitro simulation test results.

[0004] At present, there are few studies on the tensile torsional fatigue test of tracheal stents. After searching by the applicant, it was found that a similar patent with the number CN201910522331.4 announced a micro-scale polymer material mechanical property testing device, and also a device for realizing a dynamic stretching device for studying the mechanical properties of tiny-sized material specimens in the field of micro-nano device biomedicine. However, the testing process of this device does not involve the impact of the airflow passing through the tracheal stent on the tracheal wall when it is in service in the body. Utility Model Content

[0005] The technical problem to be solved by the utility model is to overcome the shortcomings of the prior art and provide a tracheal stent tensile-torsion fatigue testing device with a reasonable structure and easy use, which can solve the technical problem of evaluating the fatigue performance of the tracheal stent under the action of tensile-torsion composite load under simulated in vivo service conditions.

[0006] In order to achieve the above purpose, the specific technical scheme of the utility model is as follows: a tracheal stent tensile torsion fatigue testing device, comprising a workbench (5) placed at the bottom, a linear module (1) being vertically fixedly installed on one side of the upper surface of the workbench, a tracheal stent clamp (2) and a rotating device (3) being installed on the linear module, the tracheal stent clamp being composed of an upper clamp and a lower clamp of the same structure, the tracheal clamp vertically placed between the upper and lower clamps being fixed and clamped, the upper clamp being connected to a micro air pump installed beside the linear module, and providing a suitable airflow through the micro air pump; the lower clamp being installed on the rotating device and driven by the rotating device.

[0007] Furthermore, the linear module is composed of a ball screw (1-1), a slider (1-2), a connecting block (1-3), a displacement sensor (1-4), a tension sensor (1-5), and a motor (1-6); the ball screw is arranged along the vertical direction of the linear module, the slider is connected to the ball screw via a threaded pair, the connecting block is horizontally installed in front of the slider via bolts, the displacement sensor is horizontally installed on the left side of the slider, the tension sensor is installed below the connecting block via threads, and the motor is installed at the rear of the linear module via bolts, and the slider is driven by the motor to drive the connecting plate to reciprocate along the ball screw.

[0008] Furthermore, the upper clamp is installed below the tension sensor.

[0009] Furthermore, the upper clamp comprises a clamping frame (2-1), a silicone hose (2-2), an air inlet (2-3) and a clamping block. The clamping frame is installed below the tension sensor and is threadedly connected to the bottom of the tension sensor through an opening at the center of the top of the clamping frame; the silicone hose is installed below the clamping frame and is in the shape of a curved pipe. One end of the curved pipe is connected to the clamping frame to play a certain supporting role; it is connected to a micro air pump through an air inlet opened on the right side of the clamping frame, and the other end is connected to an air pipe bracket; the clamping block is installed at the bottom of the clamping frame and consists of a fixed clamping block (2-4) and a push-type clamping block (2-5).

[0010] Furthermore, the push-type clamping block and the fixed clamping block are respectively arranged on both sides of the silicone hose. The push-type clamping block includes a clamping block body, a threaded rod and a clamping block end. The clamping block body is fixed to the bottom of the clamping frame. The threaded rod passes through its center line in parallel and is threadedly connected to the clamping block end. The clamping block end is rectangular, and a notch is provided at the end in contact with the silicone hose. At the same time, a knob is installed on the left side of the threaded rod. The clamping of the tracheal stent can be completed by manually rotating the knob. The fixed clamping block is composed of a fixed clamping block body, and a notch is also provided at the end in contact with the silicone hose. The push-type clamping block and the fixed clamping block are used to clamp the outside of the tracheal stent.

[0011] Furthermore, the rotating device is installed below the lower clamp, and comprises a servo motor (3-1), a connecting rod (3-2) and a rotating platform (3-3); the rotating platform is horizontally installed on the workbench by bolts, the servo motor is installed on the right side of the rotating platform by bolts, and the connecting rod is installed on the rotating platform to connect the lower clamp and the rotating device.

[0012] Furthermore, the micro air pump is composed of a pump body (4-1), an air pump outlet (4-2), an air pump inlet (4-3) and a hose (4-4); the air pump outlet is connected to the air inlet on the clamping frame through the hose, and is connected to the silicone hose to achieve an in vivo simulated environment of the tracheal stent.

[0013] Furthermore, the tracheal stent is a tubular sample with a diameter of 15-20 mm.

[0014] Compared with the prior art, the beneficial effects of the utility model are as follows: the application can realize the tensile torsion fatigue test of tracheal stents of different sizes by adjusting the diameter of the silicone hose; the tracheal stent upper clamp of the utility model is connected to the tension sensor for transmitting the force condition to the force sensor; the utility model realizes the cyclic stretching-relaxation process of the sample by controlling the forward and reverse rotation of the motor; and the tracheal stent is clamped by the flat push clamp and the silicone hose to reduce the deformation of the stent, thereby improving the accuracy of the test results; at the same time, the utility model simulates the actual service condition of the tracheal stent in the body through the airflow generated by the micro air pump, further determines the fatigue life of the tracheal stent, and ensures the reliability of the test. The utility model device is small in size and flexible, and all parts and accessories can be replaced as needed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall schematic diagram of a tracheal stent tensile torsion fatigue testing device in an embodiment of the utility model.

[0016] Figure 2 for Figure 1 Schematic diagram of the structure of the linear module.

[0017] Figure 3 for Figure 1 Schematic diagram of the structure of the tracheal support fixture.

[0018] Figure 4 for Figure 1 Schematic diagram of the structure of the rotating device.

[0019] Figure 5 for Figure 1 Schematic diagram of the structure of a medium and micro air pump.

[0020] In the figure: 1 linear module; 2 trachea support fixture; 3 rotating device; 4 micro air pump; 5 workbench;

[0021] 1-1 ball screw; 1-2 slider; 1-3 connecting block; 1-4 tension sensor; 1-5 displacement sensor; 1-6 motor;

[0022] 2-1 clamping frame; 2-2 silicone hose; 2-3 air inlet; 2-4 fixed clamping block; 2-5 push-type clamping block; 3-1 servo motor; 3-2 connecting rod; 3-3 rotating platform; 4-1 pump body; 4-2 air pump outlet; 4-3 air pump inlet; 4-4 hose. DETAILED DESCRIPTION Example

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] like Figure 1 , Figure 2 As shown, a tracheal stent tensile torsion fatigue test device is composed of a linear module 1, a tracheal stent fixture 2, a rotating device 3, a micro air pump 4 and a workbench 5. The linear module 1 is installed on the workbench 5 by bolts and is perpendicular to the horizontal plane. The slider 1-2 is connected to the ball screw 1-1 by a threaded pair. The motor 1-5 drives the linear module 1 to move to achieve the reciprocating motion of the slider 1-2 in the vertical direction. The connecting block 1-3 is horizontally installed in front of the slider 1-2 by bolts, and the connecting plate 1-3 moves with the slider 1-2. The displacement sensor 1-5 is horizontally installed on the left side of the slider 1-2. The tension sensor 1-4 is installed below the connecting block 1-3 by threads. The motor 1-5 is installed behind the linear module by bolts.

[0025] like Figure 1 , Figure 3 As shown, the tracheal stent clamp 2 is composed of a clamping frame 2-1, a silicone hose 2-2, an air inlet 2-3, a fixed clamping block 2-4, and a flat-push clamping block 2-5. The clamping clamp 2-1 is installed below the tension sensor 1-5, one end of the silicone hose 2-2 is connected to the inside of the tracheal stent to play a certain supporting role, and the other end is connected to the clamping clamp 2-1 and connected to a micro air pump to ventilate the inside of the tracheal stent to simulate the in vivo service environment, and the fixed clamping block 2-4 and the flat-push clamping block 2-5 jointly clamp the outside of the tracheal stent to ensure clamping.

[0026] like Figure 4 As shown, the rotating device is composed of a servo motor 3-1, a connecting rod 3-2, and a rotating platform 3-3. The rotating platform 3-3 is horizontally mounted on the workbench 5 by bolts, the servo motor 3-1 is mounted on the right side of the rotating platform 3-3 by bolts, and the lower clamp of the tracheal support clamp 2 is connected to the rotating platform 3-3 by the connecting rod 3-2.

[0027] like Figure 5 As shown, the micro air pump is composed of a pump body 4-1, an air pump outlet 4-2, and an air pump inlet 4-3. The air pump outlet 4-2 is connected to the clamping frame 2-1 and the silicone hose 2-2 through a hose 4-4 to achieve the in vivo simulated environment of the tracheal stent.

[0028] The workflow of this embodiment is:

[0029] 1. Fix the tracheal stent sample between the upper fixture and the lower fixture of the tracheal stent.

[0030] 2. Move the slider to make the tracheal stent sample reach a taut state.

[0031] 3. Test the tensile fatigue life of the tracheal stent specimen: The specimen stretching speed is 10 mm / min. The cyclic stretching-relaxation process of the specimen is realized by controlling the forward and reverse rotation of the motor. The tension sensor records the change of the specimen force over time and the number of cycles.

[0032] 4. Test the torsional fatigue life of the tracheal stent specimen: The servo motor drives the rotating platform to rotate, providing continuous axial force until the tracheal stent specimen fails, and the maximum torque value that can be applied before the specimen fails is recorded.

[0033] The test device of the utility model can perform tensile torsion fatigue tests on tracheal stents of different sizes. The utility model clamps the tracheal stent through a flat-push clamp and a silicone hose, reduces the deformation of the stent, and thus improves the accuracy of the test results. The utility model determines the fatigue life of the tracheal stent by simulating the actual service conditions of the tracheal stent in vivo, thereby ensuring the reliability of the test.

[0034] In addition to the above embodiments, the present invention may also have other implementations. Any technical solution formed by equivalent replacement or equivalent transformation falls within the protection scope required by the present invention.

Claims

1. A tracheal stent tensile torsion fatigue test device, characterized in that: The invention comprises a workbench (5) placed at the bottom, a linear module (1) being vertically fixedly mounted on one side of the upper surface of the workbench, a trachea support fixture (2) and a rotating device (3) being mounted on the linear module, the trachea support fixture comprising an upper fixture and a lower fixture of the same structure, the trachea fixture vertically placed between the upper and lower fixtures being fixed and clamped, the upper fixture being connected to a micro air pump mounted on the side of the linear module, the lower fixture being mounted on the rotating device and driven by the rotating device.

2. The tracheal stent tensile torsion fatigue testing device according to claim 1, characterized in that: The linear module comprises a ball screw (1-1), a slider (1-2), a connecting block (1-3), a displacement sensor (1-4), a tension sensor (1-5), and a motor (1-6); the ball screw is arranged along the vertical direction of the linear module, the slider is connected to the ball screw via a threaded pair, the connecting block is horizontally installed in front of the slider via bolts, the displacement sensor is horizontally installed on the left side of the slider, the tension sensor is installed below the connecting block via threads, the motor is installed at the rear of the linear module via bolts, and the slider is driven by the motor to drive the connecting plate to reciprocate along the ball screw.

3. The tracheal stent tensile torsion fatigue testing device according to claim 2, characterized in that: The upper clamp is installed below the tension sensor.

4. The tracheal stent tensile torsion fatigue testing device according to claim 2, characterized in that: The upper clamp comprises a clamping frame (2-1), a silicone hose (2-2), an air inlet (2-3) and a clamping block. The clamping frame is installed below the tension sensor and is threadedly connected to the bottom of the tension sensor through an opening at the center of the top of the clamping frame. The silicone hose is installed below the clamping frame and is in the shape of a curved pipe. One end of the curved pipe is connected to the clamping frame and is connected to a micro air pump through an air inlet opened on the right side of the clamping frame, and the other end is connected to an air pipe bracket. The clamping block is installed at the bottom of the clamping frame and consists of a fixed clamping block (2-4) and a horizontal push clamping block (2-5).

5. The tracheal stent tensile torsion fatigue testing device according to claim 4, characterized in that: The push-type clamping block and the fixed clamping block are respectively arranged on both sides of the silicone hose, and the push-type clamping block includes a clamping block body, a threaded rod and a clamping block end. The clamping block body is fixed to the bottom of the clamping frame, and the threaded rod passes through its center line in parallel and is threadedly connected to the clamping block end, and a knob is installed on the left side of the threaded rod. The clamping block end is rectangular, and a notch is provided at one end thereof that contacts the silicone hose; the fixed clamping block is composed of a fixed clamping block body, and a notch is also provided at one end thereof that contacts the silicone hose, and the outside of the tracheal stent is clamped together by the push-type clamping block and the fixed clamping block.

6. The tracheal stent tensile torsion fatigue testing device according to claim 1, characterized in that: The rotating device is installed below the lower clamp, and comprises a servo motor (3-1), a connecting rod (3-2) and a rotating platform (3-3). The rotating platform is horizontally installed on the workbench by bolts, the servo motor is installed on the right side of the rotating platform by bolts, and the connecting rod is installed on the rotating platform to connect the lower clamp and the rotating device.

7. The tracheal stent tensile torsion fatigue testing device according to claim 1, characterized in that: The micro air pump is composed of a pump body (4-1), an air pump air outlet (4-2), an air pump air inlet (4-3) and a hose (4-4); the air pump air outlet is connected to the air inlet on the clamping frame through the hose and is connected to the silicone hose to achieve an in vivo simulated environment of the tracheal stent.

8. The tracheal stent tensile torsion fatigue testing device according to claim 1, characterized in that: The tracheal stent is a tubular sample with a diameter of 15-20 mm.

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