A tendon cross-sectional area measuring device

Abstract

The utility model belongs to the technical field of medical instrument evaluation, concretely relates to a tendon cross section area measuring device, the tendon cross section area measuring device of the utility model contains the measuring solution of known density in the measuring cylinder, because the cross section area of measuring cylinder is constant setting, the liquid level change is not influenced by the cross section area of measuring cylinder, in addition, the density of the tensile load is greater than the density of the measuring solution, therefore, the tendon is straightened and vertically enters the measuring solution by connecting the tensile load with the lower end of tendon. By connecting the lifting mechanism with the upper end of tendon, the vertical downward movement of tendon and tensile load is controlled by using the lifting mechanism, based on the density of measuring solution, the pressure difference caused by the change of liquid level can be measured by using the pressure sensor at the bottom of measuring cylinder, and then the variable of liquid level can be obtained, the average cross section area of tendon under the corresponding displacement of tensile load can be obtained based on the corresponding displacement of tensile load, and the rapid measurement of tendon cross section area is realized.

Description

Technical Field

[0001] This utility model belongs to the technical field of medical device evaluation, and specifically relates to a tendon cross-sectional area measuring device. Background Technology

[0002] Tendons are dense connective tissues that provide support, connection, and protection within the human body. The cross-sectional area of ​​a tendon is a crucial parameter for assessing its mechanical properties. To measure this cross-sectional area, numerous researchers both domestically and internationally have proposed a series of methods: the sectioning method, which involves slicing the tendon and then performing morphological measurements; this method provides relatively accurate data, but it is destructive and cannot be used for subsequent mechanical testing; the micrometer method, which determines the cross-sectional area by compressing the tendon into a rectangular groove and measuring its height; this method can easily cause irreversible damage to the sample, leading to a decrease in its mechanical properties; the volume method, which calculates the cross-sectional area by dividing the sample's volume by its length; the geometric approximation method, which approximates the sample's cross-section as a right triangle, circle, or ellipse and then measures its dimensions using tools; while convenient, these methods inevitably introduce errors, making such data unsuitable for evaluating the sample's mechanical properties; and the structured light scanning method, which calculates the sample's cross-sectional area by scanning and reconstructing a three-dimensional digital model of the soft tissue from all directions; however, the overlap during the scanning process and the cost of the equipment may present potential limitations.

[0003] In recent years, impression technology has become a relatively ideal measurement method. For example, Chinese patent document CN111184516A discloses an impression device and a method for measuring the cross-sectional area of ​​locatable soft tissue. This method involves first casting and then demolding the sample using an impression material, which can effectively "replicate" the sample. Furthermore, researchers have scribed and segmented the sample before casting, and then performed mechanical property tests on the sample after demolding. The fracture points of the sample are located on the corresponding positions in the model, and optical measurement methods or image analysis software are used to calculate the cross-sectional area at these points. While this method is economical, accurate, and does not damage the sample, the molding and demolding process is relatively complex and time-consuming. The cross-sectional area is measured by projecting the impression slice using optical measurement equipment or calculating it using image analysis software. As is well known, this method has strict requirements on the edge contour of the sample; failure to clearly and accurately depict the actual contour of the slice will further increase the measurement error. Utility Model Content

[0004] To solve the above-mentioned technical problems, based on the volumetric method and molding technology, this utility model provides a tendon cross-sectional area measuring device. The device is easy to operate, economical, and provides relatively accurate measurement results.

[0005] The technical problem to be solved by this utility model is achieved by the following technical solution: a tendon cross-sectional area measuring device, including a base, a measuring cylinder, a tensile load, a pressure sensor, a lifting mechanism and a cross-sectional area measuring module; The measuring cylinder is mounted on the base and is used to hold the measuring solution; The measuring cylinder has its opening facing upwards, and its cross-sectional area is kept constant. The tensile load is set inside the measuring cylinder, and the density of the tensile load is greater than the density of the measuring solution. The tensile load is connected to the lower end of the tendon and is used to straighten the tendon and vertically enter the measuring solution; The lifting mechanism is connected to the upper end of the tendon and is used to control the lifting and lowering of the tendon and the tension load. The pressure sensor is located at the bottom of the measuring cylinder and is electrically connected to the cross-sectional area measuring module; The cross-sectional area measurement module is used to convert the pressure variable measured by the pressure sensor into the volume variable of the measured solution, and to obtain the average cross-sectional area of ​​the tendon under the corresponding displacement based on the displacement of the tensile load.

[0006] In a preferred embodiment of this invention, the lifting mechanism includes a linear drive mechanism, a cantilever, and an upper clamp. The linear drive mechanism is vertically mounted on the base and is used to control the up-and-down sliding of the cantilever. The upper clamp is located below the cantilever. The upper clamp holds the upper end of the tendon, and a linear drive mechanism controls the up and down sliding of the cantilever, thereby achieving the purpose of controlling the tendon and raising and lowering it under load.

[0007] In a preferred embodiment of this invention, the upper clamp includes a sliding seat, a slide rail, a bidirectional lead screw, a gripper, and a knob; The slide rail is mounted on the sliding seat, and the sliding seat is installed below the cantilever. The bidirectional lead screw is rotatably mounted on the sliding seat; The two grippers are respectively disposed at both ends of the bidirectional lead screw and are slidably connected to the slide rail; The knob is coaxially connected to the bidirectional lead screw.

[0008] In a preferred embodiment of this invention, a lower clamp is provided above the tensile load. The lower clamp holds the lower end of the tendon, connecting the lower end of the tendon to the tensile load.

[0009] In a preferred embodiment of this invention, the tensile load is a weight, and the lower clamp is a dovetail clamp connected to the upper end of the weight. Using a dovetail clamp to connect to the weight results in a simple structure and allows for quick connection to the tendon.

[0010] Preferably, this utility model also includes leveling feet and an attitude indicator, wherein the leveling feet are located below the four corners of the base and are threadedly connected to the base; The attitude sensor is mounted on the base and is used to measure the angle between the base and the horizontal plane. By using the attitude sensor to measure the angle between the base and the horizontal plane, and adjusting the leveling feet to adjust the angle between the base and the horizontal plane, the liquid surface of the measured solution is kept parallel to the horizontal plane, thus avoiding the base tilting from affecting the measurement results.

[0011] In a preferred embodiment of this invention, a buffer support column is provided between the measuring cylinder and the base. Providing a buffer support column between the measuring cylinder and the base can further reduce the impact of external vibrations on the measurement results.

[0012] In a preferred embodiment of this invention, the leveling feet and buffer support columns are made of rubber, which have a buffering effect and reduce the impact of external vibrations on the measurement results.

[0013] Preferably, this utility model also includes a display screen, which is used to display the liquid level of the measured solution, the liquid level increment of the measured solution, the sampling length, and the cross-sectional area corresponding to the sampling length.

[0014] Preferably, the inner cavity of the measuring cylinder is cylindrical, and the measuring cylinder has a slender cylindrical structure, which facilitates preparation and enables more sensitive detection of minute volume changes caused by tendons, thereby improving measurement accuracy.

[0015] Compared with the prior art, the beneficial effects of this utility model are: This invention relates to a tendon cross-sectional area measuring device. A measuring solution of known density is placed inside the measuring cylinder. Since the cross-sectional area of ​​the measuring cylinder is constantly set, changes in the liquid level are unaffected by its cross-sectional area. Furthermore, the density of the tensile load is greater than the density of the measuring solution. Therefore, by connecting the tensile load to the lower end of the tendon, the tendon can be straightened and vertically inserted into the measuring solution. By connecting a lifting mechanism to the upper end of the tendon, the vertical downward movement of the tendon and the tensile load is controlled. Based on the density of the measuring solution, a pressure sensor at the bottom of the measuring cylinder measures the pressure difference caused by changes in liquid level, thus obtaining the liquid level variable. Based on the corresponding displacement of the tensile load, the average cross-sectional area of ​​the tendon at the corresponding displacement can be obtained. This enables rapid measurement of the tendon's cross-sectional area without damaging the tendon product, allowing for subsequent tensile testing. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the tendon cross-sectional area measuring device of this utility model; Figure 2 This is a perspective view of the tendon cross-sectional area measuring device of this utility model; Figure 3 This is a schematic diagram of the structure of the upper clamp described in this utility model; Figure 4 This is a schematic diagram of the display screen described in this utility model. In the diagram, there are 100 bases, 1 measuring cylinders, 2 tensile loads, 3 pressure sensors, and 4 lifting mechanisms. 41 Linear drive mechanism, 42 Cantilever, 43 Upper clamp; 431 Sliding seat, 432 Slide rail, 433 Bidirectional lead screw, 434 Clamp, 435 Knob; 5. Leveling feet, 6. Attitude gauge, 7. Buffer support column, 8. Display screen. Detailed Implementation

[0017] The technical solutions in the embodiments of this utility model will now be clearly and completely described in conjunction with the accompanying drawings.

[0018] like Figures 1-4 As shown, a tendon cross-sectional area measuring device includes a base 100, a measuring cylinder 1, a tensile load 2, a pressure sensor 3, a lifting mechanism 4, and a cross-sectional area measuring module.

[0019] The measuring cylinder 1 is mounted on the base 100 and is used to hold the measuring solution.

[0020] The measuring cylinder 1 has its opening facing upwards, and its cross-sectional area is kept constant. Specifically, the inner cavity of the measuring cylinder 1 is cylindrical, and the measuring cylinder 1 has a slender cylindrical structure.

[0021] The tensile load 2 is placed inside the measuring cylinder 1, and the density of the tensile load 2 is greater than the density of the measuring solution.

[0022] The tensile load 2 is connected to the lower end of the tendon and is used to straighten the tendon and vertically enter the measuring solution.

[0023] The lifting mechanism 4 is connected to the upper end of the tendon and is used to control the lifting and lowering of the tendon and the tension load 2.

[0024] The pressure sensor 3 is located at the bottom of the measuring cylinder 1 and is electrically connected to the cross-sectional area measuring module.

[0025] The cross-sectional area measurement module is used to convert the pressure variable measured by the pressure sensor 3 into the volume variable of the measurement solution, and to obtain the average cross-sectional area of ​​the tendon under the corresponding displacement based on the displacement of the tensile load 2.

[0026] like Figure 2 As shown, the lifting mechanism 4 includes a linear drive mechanism 41, a cantilever 42, and an upper clamp 43.

[0027] The linear drive mechanism 41 is vertically mounted on the base 100 and is used to control the up-and-down sliding of the cantilever 42.

[0028] The upper clamp 43 is located below the cantilever 42.

[0029] like Figure 3 As shown, the upper clamp 43 includes a sliding seat 431, a slide rail 432, a bidirectional lead screw 433, a gripper 434, and a knob 435.

[0030] The slide rail 432 is mounted on the slide seat 431, and the slide seat 431 is mounted below the cantilever 42.

[0031] The bidirectional lead screw 433 is rotatably mounted on the sliding seat 431.

[0032] The two grippers 434 are respectively disposed at both ends of the bidirectional lead screw 433 and are slidably connected to the slide rail 432. The threads of the studs at both ends of the bidirectional lead screw 433 are in opposite directions. By rotating the bidirectional lead screw 433, the two grippers 434 can be driven to move relative to each other.

[0033] The knob 435 is coaxially connected to the bidirectional lead screw 433.

[0034] A lower clamp is provided above the tensile load 2.

[0035] The tensile load 2 is a weight, and the lower clamp is a dovetail clamp connected to the upper end of the weight.

[0036] The tendon cross-sectional area measuring device also includes leveling feet 5 and posture meter 6. The leveling feet 5 are located below the four corners of the base 100 and are threadedly connected to the base 100.

[0037] The attitude sensor 6 is mounted on the base 100 and is used to measure the angle between the base 100 and the horizontal plane.

[0038] A buffer support column 7 is provided between the measuring cylinder 1 and the base 100.

[0039] The leveling feet 5 and the buffer support column 7 are made of rubber.

[0040] like Figure 1 and Figure 4 As shown, the tendon cross-sectional area measuring device also includes a display screen 8, which is used to display the liquid level of the measuring solution, the liquid level increment of the measuring solution, the sampling length, and the cross-sectional area corresponding to the sampling length.

[0041] Specific testing methods: ① Distinguish the names of the two ends of the tendon product sample, for example, head end and tail end; tip and tip; end 1 and end 2; end A and end B.

[0042] ② At a certain distance from the tendon head (e.g., 50mm, leaving sufficient clamping length, this point is marked as the end point), use appropriate tools to mark at regular intervals (e.g., 1mm, 2mm, 5mm, 10mm... The smaller the interval, the more accurate the cross-sectional area information of the sample can be obtained. This scheme takes 10mm as an example) until 50mm from the tail end, this point is marked as the starting point (the area from the starting point to the end point is the test area).

[0043] ③ Fix the head end of the tendon specimen to a device that can accurately control the downward displacement of the specimen, and attach an object of a certain mass, such as a weight, to the tail end of the specimen to overcome the buoyancy of the water and ensure that the specimen is straightened.

[0044] ④ Inject an appropriate amount of physiological saline into the relatively slender measuring cylinder 1, which can accurately measure the volume of the liquid.

[0045] ⑤ Slowly place the sample into the container and make the starting point tangent to the liquid surface. Record the liquid volume V1 in the container at this time, in units of 10 mm. Immerse the sample in physiological saline and record the liquid volume V2, V3, V4, V5, etc. for each 1 cm of sample immersed.

[0046] ⑥V2-V1,V3-V2,V4-V3,V5-V4...... are the volumes of the sample per 10mm from the starting point. Dividing this value by 10mm gives the cross-sectional area of ​​the sample.

[0047] In addition, by slowly pulling the sample at a certain speed, and by using the values ​​of liquid level change and the speed at which the sample is immersed in the water, a time (t) - liquid level change (h) graph is plotted. This allows us to obtain the point of minimum slope (which is the point where the sample is thinnest), calculate the cross-sectional area of ​​this point, and the average cross-sectional area within a 5mm range above and below it. We then focus on the changes at this point during the tensile test.

Claims

1. A device for measuring the cross-sectional area of ​​a tendon, characterized in that: It includes a base (100), a measuring cylinder (1), a tensile load (2), a pressure sensor (3), a lifting mechanism (4), and a cross-sectional area measuring module; The measuring cylinder (1) is mounted on the base (100) and is used to hold the measuring solution; The measuring cylinder (1) has its opening facing upwards, and the cross-sectional area of ​​the measuring cylinder (1) is set to be constant. The tensile load (2) is set inside the measuring cylinder (1), and the density of the tensile load (2) is greater than the density of the measuring solution; The stretching load (2) is connected to the lower end of the tendon and is used to straighten the tendon and vertically enter the measuring solution; The lifting mechanism (4) is connected to the upper end of the tendon and is used to control the lifting and lowering of the tendon and the stretching load (2); The pressure sensor (3) is located at the bottom of the measuring cylinder (1) and is electrically connected to the cross-sectional area measuring module; The cross-sectional area measurement module is used to convert the pressure variable measured by the pressure sensor (3) into the volume variable of the measurement solution, and to obtain the average cross-sectional area of ​​the tendon under the corresponding displacement based on the corresponding displacement of the tensile load (2).

2. The tendon cross-sectional area measuring device according to claim 1, characterized in that: The lifting mechanism (4) includes a linear drive mechanism (41), a cantilever (42), and an upper clamp (43). The linear drive mechanism (41) is vertically mounted on the base (100) and is used to control the up and down sliding of the cantilever (42); The upper clamp (43) is located below the cantilever (42).

3. The tendon cross-sectional area measuring device according to claim 2, characterized in that: The upper clamp (43) includes a sliding seat (431), a slide rail (432), a two-way lead screw (433), a jaw (434), and a knob (435). The slide rail (432) is mounted on the sliding seat (431), which is installed below the cantilever (42); The bidirectional lead screw (433) is rotatably mounted on the sliding seat (431); The two grippers (434) are respectively disposed at both ends of the bidirectional lead screw (433) and are slidably connected to the slide rail (432); The knob (435) is coaxially connected to the bidirectional lead screw (433).

4. The tendon cross-sectional area measuring device according to claim 1 or 2, characterized in that: A lower clamp is provided above the tensile load (2).

5. The tendon cross-sectional area measuring device according to claim 4, characterized in that: The tensile load (2) is a weight, and the lower clamp is a dovetail clamp connected to the upper end of the weight.

6. The tendon cross-sectional area measuring device according to claim 1, characterized in that: It also includes leveling feet (5) and attitude indicator (6), wherein the leveling feet (5) are located below the four corners of the base (100), and the leveling feet (5) are threadedly connected to the base (100); The attitude sensor (6) is mounted on the base (100) and is used to measure the angle between the base (100) and the horizontal plane.

7. The tendon cross-sectional area measuring device according to claim 6, characterized in that: A buffer support column (7) is provided between the measuring cylinder (1) and the base (100).

8. The tendon cross-sectional area measuring device according to claim 7, characterized in that: The leveling feet (5) and buffer support columns (7) are made of rubber.

9. The tendon cross-sectional area measuring device according to claim 1, characterized in that: It also includes a display screen (8) for displaying the liquid level of the measured solution, the liquid level increment of the measured solution, the sampling length, and the cross-sectional area corresponding to the sampling length.

10. The tendon cross-sectional area measuring device according to claim 1, characterized in that: The inner cavity of the measuring cylinder (1) is cylindrical, and the measuring cylinder (1) has a slender cylindrical structure.

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