A nerve traction and online measurement device and working method

Abstract

The present application belongs to the field of nerve traction equipment, and provides a nerve traction and online measurement device and a working method thereof. The nerve traction and online measurement device comprises an open container, a piston and a measurement module. The piston is arranged in the open container and is in contact with the inner wall of the open container to form a sealed space. The piston is connected to one end of a movable rod, the movable rod extends out of the open container by a preset length and is connected to the distal end of a broken nerve. A fixed rod is installed at a position opposite to the open container where the movable rod extends out, and the fixed rod is connected to the proximal end of the broken nerve. There is a pressure difference between the inside and outside of the device, which drives the movable rod to linearly pull the nerve. The measurement module is used to obtain the pressure and temperature data of the known gas in the sealed space, and then based on the ideal gas state equation, the volume of the sealed gas is calculated, and then the displacement of the piston and the pulling force are obtained, that is, the nerve deformation and the pulling force are measured simultaneously.

Description

Technical Field

[0001] This invention belongs to the field of nerve traction equipment, and particularly relates to a nerve traction and online measurement device and working method. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] Clinically, peripheral nerve defects are repaired using methods such as autologous nerve transplantation or extending existing materials. The latter works on the principle that moderate tension loading can accelerate neuronal growth, allowing proximal and distal nerves to grow to a suitable length for repair. Nerve traction surgery is currently in the clinical trial research stage. Using effective traction devices and collecting accurate and reliable nerve traction signals, including nerve growth length and the optimal traction force for growth, is of great significance for improving nerve traction process data, establishing nerve growth models, and advancing current clinical research.

[0004] Traction devices need to meet requirements such as implantation within the body and slow elongation. Currently, there are two types: one is a balloon-structured dilator, such as the dilator in CN217907851U. Its principle is to use the surface tension of the balloon to stretch the nerve after water is injected. The disadvantage of this device is that the nerve traction path is not straight, resulting in poor traction effect. The other type is a widely used nerve dilator, such as the dilator in CN 216702585U. It has a good traction and elongation effect, but its disadvantage is that the nerve dilator device is simple and cannot obtain traction force and real-time deformation. Furthermore, traction methods that implant the entire traction device, including the drive structure, within the body cannot be implanted for long periods due to the inability of the battery to continuously provide a power source.

[0005] The effectiveness of traction devices is typically verified by detecting traction force and displacement. However, there are two existing types of force-displacement dual-parameter sensors. One type uses springs, cantilever beams, and inductive sensors based on electromagnetic induction to directly obtain both force and displacement parameters. The drawback is its complex structure and large size; reducing its size would significantly increase costs. The other type is a force-displacement dual-parameter sensor based on parallel data, which integrates two sensing chips (a force sensing chip and a displacement sensing chip) within the traction device to acquire data separately. The inventors discovered that the aforementioned displacement sensing chip cannot work in conjunction with existing nerve expanders. If directly placed, the sensing chip malfunctions and is prone to causing infection. Summary of the Invention

[0006] To address the technical problems existing in the background art, the present invention provides a nerve traction and online measurement device and its working method, which utilizes pressure difference to achieve linear nerve traction with good traction effect; while realizing the traction function, it calculates the traction force and nerve displacement based on the pressure and temperature obtained by the measurement module to realize the measurement function.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In one or more embodiments, a nerve traction and online measurement device is provided, comprising:

[0009] Open container, piston, and measuring module;

[0010] The piston is disposed inside the open container and contacts the inner wall of the open container to form a sealed space, which is pre-filled with a known gas.

[0011] The piston is connected to one end of the movable rod, and a fixed rod is installed at the open container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position.

[0012] The measuring module is housed within a sealed space, and the measuring module is used for:

[0013] The pressure and temperature data of the known gas in the sealed space are obtained, and the volume of the sealed gas is calculated based on the ideal gas law. Then, the displacement and tension of the piston are obtained, that is, the deformation and traction force of the piston are measured at the same time.

[0014] In one implementation, the process of calculating the tension on the piston in the measurement module includes:

[0015] Based on the proportional relationship between the initial working pressure and the initial working temperature, the pressure correction coefficient is determined by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure.

[0016] The pressure difference between the two sides of the piston is calculated using the corrected pressure, and then combined with the effective contact area between the piston and the sealing gas, the pressure difference between the two sides of the piston is obtained.

[0017] Calculate the difference between the pressure difference on both sides of the piston and the difference in friction to obtain the tension force on the piston.

[0018] In one embodiment, at least one sealing ring is fitted on the outer side of the piston, and the sealing ring contacts the inner wall of the sealing container.

[0019] In one implementation, a friction correction coefficient is introduced to correct the friction force during the process of the measurement module calculating the tension on the piston; the friction correction coefficient is obtained based on the dynamic and static friction conversion curve between the sealing ring and the inner wall of the sealing container.

[0020] In one embodiment, the movable rod is connected to the distal end of the severed nerve through a first fixing hole;

[0021] In one embodiment, the fixing rod is connected to the proximal end of the severed nerve through a second fixing hole;

[0022] In one embodiment, the sealed space is pre-filled with one or more uniformly mixed gases.

[0023] In one implementation, the sealed space is also connected to a suction pipe via a connector to extract gas from the sealed space, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0024] A method for operating a nerve traction and online measurement device as described above, comprising:

[0025] After the movable rod moves a set distance away from the fixed rod from the air pressure balance position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively, so as to use the force of the movable rod gradually returning to the air pressure balance position to stretch the severed nerve.

[0026] Obtain the pressure and temperature data of the known gas in the sealed space. Based on the ratio between the initial working pressure and the initial working temperature, determine the pressure correction coefficient by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure.

[0027] Using the corrected pressure and based on the ideal gas law, the volume of the sealed gas is calculated, and then the displacement and tension of the piston are obtained, that is, the deformation and traction force of the nerve are measured at the same time.

[0028] When the movable rod returns to the air pressure balance position, the gas in the sealed space is extracted, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0029] In some embodiments, another nerve traction and online measurement device is also provided, comprising:

[0030] Sealed container, piston, and measuring module;

[0031] The piston is disposed inside the sealed container, which initially divides the sealed container into two identical sealed spaces; each sealed space is equipped with a measuring module; the two sealed spaces are pre-filled with the same known gas;

[0032] The piston is connected to one end of the movable rod, and a fixed rod is installed at the sealed container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position.

[0033] The measurement module described herein is used to: acquire pressure and temperature data of known gases in two sealed spaces, and then calculate the volume change of the sealed gas based on the ideal gas law, thereby obtaining the displacement and tension of the piston, i.e., simultaneously measuring the deformation and traction force of the piston.

[0034] In one embodiment, at least one sealing ring is fitted on the outer side of the piston, and the sealing ring contacts the inner wall of the sealing container.

[0035] In one embodiment, the movable rod is connected to the distal end of the severed nerve through a first fixing hole;

[0036] In one embodiment, the fixing rod is connected to the proximal end of the severed nerve through a second fixing hole;

[0037] In one embodiment, the sealed container is pre-filled with one or more uniformly mixed gases.

[0038] In one implementation, the sealed space near the fixed rod is also connected to an air extraction pipe via a connector to extract gas from the sealed space, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0039] The method for using the nerve traction and online measurement device as described above includes:

[0040] After the movable rod moves a set distance away from the fixed rod from the air pressure balance position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively, so as to use the force of the movable rod gradually returning to the air pressure balance position to stretch the severed nerve.

[0041] By acquiring the pressure and temperature data of the known gases in two sealed spaces, and then calculating the volume change of the sealed gas based on the ideal gas law, the displacement and tension of the piston can be obtained, that is, the deformation and traction force of the piston can be measured simultaneously.

[0042] When the movable rod returns to the air pressure balance position, the gas in the sealed space is extracted, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0043] Compared with the prior art, the beneficial effects of the present invention are:

[0044] (1) This invention utilizes pressure difference to achieve linear traction function. After the movable rod moves a set distance away from the fixed rod from the air pressure equilibrium position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively. The force of the movable rod gradually returning to the air pressure equilibrium position is used to stretch the severed nerve. Based on the ideal gas state equation, the volume change of the sealed gas is calculated, and then the displacement of the piston and the tension are obtained. That is, the nerve deformation and traction force are measured at the same time, and the traction and measurement functions are realized simultaneously.

[0045] (2) The present invention provides that the nerve traction device is an implantable nerve traction device. The device is also connected to the air extraction tube through a connector to extract gas in the sealed space. This increases both the traction threshold and the measurement threshold of the in vivo traction device, thus ensuring linear traction and a simple device structure, which is beneficial to wound healing.

[0046] (3) The nerve traction and online measurement device of the present invention is based on the ideal gas equation of state, which can realize the online measurement of nerve traction and traction force-displacement dual parameters. By obtaining the pressure and temperature state of the sealed gas, the traction force and displacement of the device can be calculated. During the nerve traction process, the two important parameters of nerve traction force and deformation are obtained at the same time, which overcomes the defect that the current implantable nerve traction device cannot simultaneously measure traction force and real-time deformation, which is conducive to the establishment of nerve growth model.

[0047] (4) In practical applications, the nerve traction and online measurement device of the present invention needs to be implanted in the body. Even in a homeothermic animal, it is difficult to guarantee an absolutely constant temperature. When the temperature changes, since the device has good thermal conductivity, the sealed gas is at the same temperature as the environment where the device is located, so the pressure difference does not change. However, due to the increase in temperature, according to the ideal gas equation, the pressure of the sealed gas increases. Based on the ratio of the initial working pressure to the initial working temperature, the pressure correction coefficient is determined by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure, thereby obtaining an accurate pressure difference and traction force.

[0048] (5) The nerve traction and online measurement device of the present invention uses a piston to initially divide the sealed container into two identical sealed spaces. Each sealed space is equipped with a measurement module. The two sealed spaces are pre-filled with the same known gas to form a differential structure, which effectively improves the pressure difference caused by temperature changes and improves the sensitivity of the nerve traction and online measurement device.

[0049] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0050] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0051] Figure 1 This is an exploded view of the nerve traction and online measurement device according to Embodiment 1 of the present invention;

[0052] Figure 2 This is a schematic diagram of the nerve traction and online measurement device according to Embodiment 1 of the present invention;

[0053] Figure 3 This is a schematic diagram of the sensitive chip in Embodiment 1 of the present invention;

[0054] Figure 4 This is a schematic diagram of the active nerve traction online measurement principle of Embodiment 1 of the present invention;

[0055] Figure 5(a) shows the original state of the first embodiment of the present invention when filled with a single gas (compression factor Z1);

[0056] Figure 5(b) shows the maximum stretching state of Embodiment 1 of the present invention filled with the same single gas as in Figure 5(a);

[0057] Figure 5(c) shows the initial state of the first embodiment of the present invention filled with another single gas (compressibility factor Z2); wherein, Z2>Z1;

[0058] Figure 5(d) shows the maximum stretching state of the same single gas as in Figure 5(c) in Embodiment 1 of the present invention;

[0059] Figure 5(e) shows the initial state of the two mixed gases (compression factor Z3) in Embodiment 1 of the present invention; wherein, Z3>Z2;

[0060] Figure 5(f) shows the maximum stretching state of the embodiment of the present invention filled with the same mixed gas as in Figure 5(e);

[0061] Figure 6 This is a schematic diagram of the nerve traction and online measurement device according to Embodiment 2 of the present invention;

[0062] Figure 7 This is a schematic diagram of the air extraction device structure according to Embodiment 2 of the present invention;

[0063] Figure 8 This is a schematic diagram of the nerve traction and online measurement device connected to the air extraction device in Embodiment 2 of the present invention;

[0064] Figure 9 This is a schematic diagram of the nerve traction and online measurement device according to Embodiment 3 of the present invention;

[0065] Figure 10(a) shows the initial state of the nerve traction and online measurement device according to Embodiment 3 of the present invention;

[0066] Figure 10(b) shows the working status of the nerve traction and online measurement device according to Embodiment 3 of the present invention;

[0067] Figure 11 This is a sensitivity comparison diagram of the nerve traction and online measurement device in Embodiment 3 and Embodiment 1 of the present invention.

[0068] The components are as follows: 1. Fixed rod; 2. Open container; 3. Piston; 4. First movable rod; 5. Fixed hole; 6. First-stage sealing ring; 7. Second-stage sealing ring; 8. Resistor and capacitor; 9. Sensitive chip; 10. Microprocessor; 11. Sealed container; 12. Retaining ring; 13. Retaining ring sealing ring; 14. Fixed sleeve; 15. Second movable rod; 16. Metal elastic membrane; 17. Alloy thin film resistor; 18. Thermistor; 19. Pressure measuring circuit; 20. Temperature measuring circuit; 21. Connector; 22. Vacuum pipe; 23. Gas check valve; 24. Vacuum pump; 25. Exhaust port; 26. Sealing cap. Detailed Implementation

[0069] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0070] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0071] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0072] Example 1

[0073] according to Figure 1 and Figure 2 This embodiment provides a nerve traction and online measurement device, which includes: an open container, a piston, and a measurement module;

[0074] The piston is disposed inside the open container and contacts the inner wall of the open container to form a sealed space, which is pre-filled with a known gas.

[0075] The piston is connected to one end of the movable rod, and a fixed rod is installed at the open container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position.

[0076] The measuring module is housed within a sealed space, and the measuring module is used for:

[0077] The pressure and temperature data of the known gas in the sealed space are obtained, and the volume of the sealed gas is calculated based on the ideal gas law. Then, the displacement and tension of the piston are obtained, that is, the deformation and traction force of the piston are measured at the same time.

[0078] The shape of the open container can be cylindrical, or it can be specifically set by those skilled in the art according to the actual situation, which will not be elaborated here.

[0079] The following describes in detail the specific structure of the nerve traction and online measurement device in this embodiment, using an open cylindrical container as an example.

[0080] In practice, the movable rod is connected to the distal end of the severed nerve through the first fixing hole; the fixed rod is connected to the proximal end of the severed nerve through the second fixing hole.

[0081] In practical implementation, the measurement module includes a sensitive element and a microcontroller. The sensitive element detects the pressure and temperature data of the known gas within the sealed space and transmits it to the microcontroller. The microcontroller calculates the displacement and tension of the piston based on the ideal gas law, and simultaneously measures the neural deformation and traction force. The microcontroller is also connected to a wireless communication module, which is connected to an external monitoring terminal.

[0082] The metal elastic membrane 16 has a strained region and a non-strained region. An alloy thin-film resistor 17 covers the strained region, and a thermal resistor 18 covers the non-strained region. Both resistors are encapsulated in the sensitive chip 9. The sensitive chip 9 is used to sense changes in gas pressure and temperature signals inside the sealed cavity, convert and amplify them, and the microprocessor is used for data calculation and transmission to the external monitoring terminal via a wireless communication module.

[0083] It should be noted that the wireless communication module includes, but is not limited to, wireless communication methods such as Bluetooth, Wi-Fi, and NFC. The advantage of this technical solution is that when the force and displacement dual-parameter sensor is implanted inside the body, real-time data can be obtained non-invasively from outside the body.

[0084] Specifically, such as Figure 3As shown, the alloy thin-film resistor 17 in the sensitive element 9 senses the pressure change, the pressure measurement circuit 19 converts and amplifies the pressure signal, and the microprocessor 10 calculates the pressure based on the pressure signal; when the body temperature changes, the thermal resistor 18 in the sensitive element 9 senses the temperature change, the temperature measurement circuit 20 converts and amplifies the temperature signal to obtain temperature data, and calculates the pressure when the temperature changes; after the nerve grows and deforms, the piston 3 moves towards the fixed rod 1, and the volume of the sealed gas can be calculated based on the pressure and temperature signals, and the piston displacement, i.e., the nerve deformation, can be further calculated; the pressure and displacement data are both wirelessly output through the communication module.

[0085] according to Figure 4 In the measurement module, the process of calculating the tension on the piston includes:

[0086] Based on the proportional relationship between the initial working pressure and the initial working temperature, the pressure correction coefficient is determined by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure.

[0087] The pressure difference between the two sides of the piston is calculated using the corrected pressure, and then combined with the effective contact area between the piston and the sealing gas, the pressure difference between the two sides of the piston is obtained.

[0088] Calculate the difference between the pressure difference on both sides of the piston and the difference in friction to obtain the tension force on the piston.

[0089] The piston is fitted with at least one sealing ring on its outer side, and the sealing ring is in contact with the inner wall of the sealing container.

[0090] When the piston is fitted with two-stage sealing rings (such as O-rings), the sealing rings are in contact with the inner wall of the sealed container.

[0091] The first-stage sealing ring provides a seal under normal conditions, while the second-stage sealing ring serves as a safety seal and radial positioning mechanism. Orientation positioning ensures the piston slides along the inner wall of the container without eccentricity or tilting, allowing the nerve to grow axially. Safety sealing prevents gas leakage when the first-stage sealing ring fails; the traction force generates an unusual falling edge signal, unlike the normally slowly changing falling edge signal, alerting the surgical operator to the failure of the first-stage sealing ring. Considering the operating environment of the device, safety safeguards are essential.

[0092] In this embodiment, the materials of the sealed container and the traction rods at both ends of the implantable traction device that are in direct contact with the living body should have good biocompatibility, including but not limited to medical-grade PVC, or coated with medical implant coatings such as hydroxyapatite and Parylene.

[0093] In one implementation, a friction correction coefficient is introduced to correct the friction force during the process of the measurement module calculating the tension on the piston; the friction correction coefficient is obtained based on the dynamic and static friction conversion curve between the sealing ring and the inner wall of the sealing container.

[0094] The working principle of the nerve traction and online measurement device in this embodiment is as follows:

[0095] The process of measuring traction force is as follows:

[0096]

[0097] In the formula, F is the traction force on the movable rod. Δ The pressure difference across the piston. The frictional force is in the same direction as the pressure exerted by the gas inside the sealed cavity on the piston.

[0098] F Δ =(p0-p)A

[0099] In the formula, F Δ p0-p is the pressure difference between the two sides of the piston, which is the pressure difference between the sealed gas and the external atmospheric pressure, i.e., the pressure difference between the two sides of the piston. The pressure data is obtained by the sensitive chip, and A is the effective area of ​​the piston in contact with the sealed gas.

[0100]

[0101] Assuming the frictional force is a fixed constant determined by the material and type of gas, and considering the slow sliding of the piston during nerve traction, a frictional correction coefficient ε is introduced. f The value is determined based on the dynamic and static friction conversion curve between the sealing ring (such as an O-ring) and the container wall.

[0102] F f =μF N

[0103] In the formula, the frictional force F f The friction coefficient μ is caused by the rough surfaces of the O-ring and the inner wall of the cylindrical cavity. It depends on the materials of the O-ring and the cylindrical cavity, as well as the type of sealing gas. N This refers to the preload force applied to the piston, O-ring, and the inner wall surface of the cylindrical cavity.

[0104] The ideal gas law is PV = nRT.

[0105] In the formula, p is the pressure, V is the gas volume, T is the temperature, n is the amount of substance of the gas, and R is the molar gas constant.

[0106] Correction pressure

[0107] Pressure correction factor: Δt=T2-T1

[0108] In the formula, p is the measured pressure. To correct for the pressure, p1 and T1 are the initial working pressure and temperature, T2 is the final temperature, and Δt is the temperature difference. The temperature data is also obtained by the sensitive chip.

[0109] In practical applications, the device needs to be implanted in the body to work. Even in the body of a homeothermic animal, it is difficult to guarantee an absolutely constant temperature. When the temperature changes, because the device has good thermal conductivity, the temperature of the sealed gas is the same as that of the environment in which the device is located (rising or falling), so the pressure difference does not change. However, due to the increase in temperature, according to the ideal gas equation, the pressure of the sealed gas increases. By obtaining temperature data, a pressure correction coefficient is introduced to correct the pressure, thereby obtaining an accurate pressure difference and traction force.

[0110] The process of measuring displacement (traction deformation) is as follows:

[0111] Given the pressure and temperature of the sealed gas, the volume of the sealed gas can be calculated, and then the piston displacement and nerve deformation can be obtained.

[0112] ΔV = V2 - V1,

[0113] In the formula, L is the nerve traction deformation, Δl is the piston displacement, V1 is the initial volume, V2 is the final volume, ΔV is the change in sealed gas volume, S is the bottom area of ​​the container; p is the pressure, V is the gas volume, T is the temperature, n is the amount of substance of the gas, and R is the molar gas constant.

[0114] The sealed space is pre-filled with one or more uniformly mixed gases.

[0115] The sealing ring mates with the piston and the surface of the sealing container to form a sealed cavity. The sealed cavity is used to encapsulate one or more homogeneous mixed gases as a transmission medium and a lubricating medium for the piston. The sealing gas is readily available air, or a non-toxic, non-liquefiable, and compressible pure gas such as nitrogen, or a homogeneous mixed gas such as a mixture of nitrogen and oxygen, or a nano-gas storage material such as a novel palladium hydride nanomaterial (this material can store hydrogen and effectively control the release of hydrogen).

[0116] Furthermore, in this embodiment, the sealing container and piston materials have good thermal conductivity.

[0117] In this embodiment, the pressure range of the sensitive chip is 26 kPa to 126 kPa, and the operating temperature is -30 to 105 °C. The compressibility factor of the sealed gas is Z = 1, the effective bottom radius of the piston is R = 2.5 mm, the volume of the sealed gas is 0.02 mL, 0.03 mL, and 0.04 mL, the initial pressure of the sealed gas is 118565 Pa, the initial temperature is 24 °C, the friction between the O-ring and the container is 20 mN, the traction force is equal to 1 N (the maximum traction force that does not damage the nerve), the pressure of the sealed gas is 68654 Pa, the pressure difference is 49911 Pa, the volume change is 0.014 mL, 0.021 mL, and 0.029 mL, and the piston displacement is 0.74 mm, 1.11 mm, and 1.48 mm. The Z compressibility factor equation of state is used to modify the deviation of the real gas from the ideal gas. Figure 5(a) shows the initial state of this embodiment when filled with a single gas (compressibility factor Z1); Figure 5(b) shows the maximum tensile state of this embodiment when filled with the same single gas as in Figure 5(a). In the initial state, the axial force F1 of the movable rod is 0, and its position is denoted as L1; Figure 5(b) shows the maximum tensile state where the axial force F1 of the movable rod is F... MAX1 The dual-parameter sensor simultaneously reaches the maximum force and displacement range F when the compressibility factor is Z1. MAX1 With L MAX1 Figure 5(c) shows the initial state of this embodiment filled with another single gas (compressibility factor Z2); where Z2>Z1; Figure 5(d) shows the maximum stretching state of this embodiment filled with the same single gas as in Figure 5(c); Figure 5(e) shows the initial state of this embodiment filled with two mixed gases (compressibility factor Z3); where Z3>Z2; Figure 5(f) shows the maximum stretching state of this embodiment filled with the same mixed gas as in Figure 5(e);

[0118] The state equation for compressibility factor Z is pV = ZnRT, where the compressibility factor Z reflects the degree of deviation of a real gas from an ideal gas. The dimension of Z is 1, and for an ideal gas, Z = 1. Different real gases have different compressibility factors. If Z < 1, it means that it is easier to compress than an ideal gas; if Z > 1, it means that it is more difficult to compress than an ideal gas.

[0119] The working method of the nerve traction and online measurement device described above includes:

[0120] After the movable rod moves a set distance away from the fixed rod from the air pressure balance position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively, so as to use the force of the movable rod gradually returning to the air pressure balance position to stretch the severed nerve.

[0121] Obtain the pressure and temperature data of the known gas in the sealed space. Based on the ratio between the initial working pressure and the initial working temperature, determine the pressure correction coefficient by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure.

[0122] Using the corrected pressure and based on the ideal gas law, the volume of the sealed gas is calculated, and then the displacement and tension of the piston are obtained, that is, the deformation and traction force of the nerve are measured at the same time.

[0123] Example 2

[0124] like Figures 6-8 As shown, in this embodiment, based on Embodiment 1, the sealed space is further connected to a suction pipe via a connector to extract gas from the sealed space. During the device's traction process, the traction operation status can be obtained based on pressure and displacement data.

[0125] Specifically, such as Figure 8 The middle state ① is a schematic diagram of the initial state of the device. The exhaust pipe 22 and the uncovered cylindrical sealed container 2 are a gas-connected closed space. Figure 8 State ② is a schematic diagram of the device's operating state; for example... Figure 8 In state ③, the current working condition is equal to the traction length threshold of the traction device or exceeds the preset working traction force range; for example... Figure 8 ④ Open the vacuum pump 24 and the exhaust port 26. The vacuum pipe 22 is connected to the uncovered cylindrical sealed container 2 via connector 21 and to the vacuum pump 24 via gas check valve 23, forming a gas path. The gas check valve 23 ensures that the gas path is a one-way gas path from the uncovered cylindrical sealed container 2 to the vacuum pump 24. After the vacuuming is completed, close the vacuum pump 24 and the exhaust port 26. Figure 8 In state ⑤, the internal traction device is once again within the traction and measurement range and continues to operate.

[0126] Within a certain period of time, not exceeding the traction deformation threshold (or within the working traction force range), the mass of the sealing gas in the internal traction device remains constant. Figure 8 In the middle state, gas check valves 23 are all closed, and the extraction pipe 22 and the uncovered cylindrical sealed container 2 form a gas-sealed space. Figure 8 State ④ is a momentary state, meaning the pump shuts off after the gas extraction is complete.

[0127] The working method of the nerve traction and online measurement device described above includes:

[0128] After the movable rod moves a set distance away from the fixed rod from the air pressure balance position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively, so as to use the force of the movable rod gradually returning to the air pressure balance position to stretch the severed nerve.

[0129] Obtain the pressure and temperature data of the known gas in the sealed space. Based on the ratio between the initial working pressure and the initial working temperature, determine the pressure correction coefficient by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure.

[0130] Using the corrected pressure and based on the ideal gas law, the volume of the sealed gas is calculated, and then the displacement of the piston and the tension are obtained, that is, the nerve deformation and traction force are measured at the same time.

[0131] When the movable rod returns to the air pressure balance position, the gas in the sealed space is extracted, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0132] Example 3

[0133] like Figure 9 As shown, a nerve traction and online measurement device is provided, which includes: a sealed container, a piston, and a measurement module;

[0134] The piston is disposed inside the sealed container, which initially divides the sealed container into two identical sealed spaces; each sealed space is equipped with a measuring module; the two sealed spaces are pre-filled with the same known gas;

[0135] The piston is connected to one end of the movable rod, and a fixed rod is installed at the sealed container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position.

[0136] The measurement module described herein is used to: acquire pressure and temperature data of known gases in two sealed spaces, and then calculate the volume change of the sealed gas based on the ideal gas law, thereby obtaining the displacement and tension of the piston, i.e., simultaneously measuring the deformation and traction force of the piston.

[0137] The piston is fitted with at least one sealing ring on its outer side, and the sealing ring contacts the inner wall of the sealing container. The movable rod is connected to the distal end of the severed nerve through a first fixing hole; the fixed rod is connected to the proximal end of the severed nerve through a second fixing hole; the sealing container is pre-filled with one or more homogeneous mixed gases.

[0138] The online measurement device in this embodiment is a differential structure. This preferred structure does not introduce a temperature correction coefficient. The differential structure effectively mitigates the pressure difference caused by temperature changes, while simultaneously increasing the device's sensitivity by approximately twice that of the original structure. The differential structure uses two sensor chips to obtain the pressure difference, eliminating the need for a temperature correction coefficient and thus eliminating pressure variations caused by temperature changes. Figure 11 As shown.

[0139] As shown in Figure 10(a), the sealed container is divided into two closed spaces with the same volume V0 by the piston, filled with the same gas, pressure p0, and temperature T0; as shown in Figure 10(b), when the sensor is working, the volume of the right cavity V1=V0-ΔV, the pressure is p1=p0+Δp, the volume of the left cavity V2=V0+ΔV, and the pressure is p2=p0-Δp.

[0140] The pressure difference between the left and right chambers, p1-p2 = (p0+Δp)-(p0-Δp) = 2Δp, increases the sensitivity coefficient k1 to twice that of a single chamber; when the temperature changes by Δt, the pressure in the right chamber, p1' = p0+Δp+Δp t1 Left cavity pressure:

[0141]

[0142] The sensitivity coefficient k1 is increased to approximately twice that of a single cavity.

[0143] In the above description, p0, V0, and T0 represent the pressure and volume of the left and right cavities in the initial state; p1 and V1 represent the pressure and volume of the right cavity when the temperature remains constant; p2 and V2 represent the pressure and volume of the left cavity when the temperature remains constant; ΔV represents the change in volume between the left and right cavities, with the right cavity decreasing by ΔV and the left cavity increasing by ΔV; when the temperature changes, the pressure and volume of the right cavity are p1' and V1', and the pressure and volume of the left cavity are p2' and V2', Δp t1 Δp t2 These represent the pressure changes in the right and left cavities caused by temperature variations.

[0144]

[0145] In the formula, ε is the rate of change of the sealed gas volume, p is the initial pressure of the sealed gas, V is the initial volume of the sealed gas, and the pressure change ΔP and volume change ΔV are calculated from the above formula.

[0146]

[0147] In the formula, n is the amount of substance of the gas, R is the molar gas constant, p1', p2', V1', and V2' are the pressure and volume of the right and left cavities after the temperature change, respectively. The data of p1', p2' and T0, Δt are obtained by the sensitive chip.

[0148] In one or more embodiments, the sealed space near the fixed rod is also connected to an air extraction pipe via a connector to extract gas from the sealed space, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0149] The method for using the nerve traction and online measurement device as described above includes:

[0150] After the movable rod moves a set distance away from the fixed rod from the air pressure balance position, the movable rod and the fixed rod are connected to the distal and proximal ends of the severed nerve, respectively, so as to use the force of the movable rod gradually returning to the air pressure balance position to stretch the severed nerve.

[0151] By acquiring the pressure and temperature data of the known gases in two sealed spaces, and then calculating the volume change of the sealed gas based on the ideal gas law, the displacement and tension of the piston can be obtained, that is, the deformation and traction force of the piston can be measured simultaneously.

[0152] When the movable rod returns to the air pressure balance position, the gas in the sealed space is extracted, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

[0153] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A nerve traction and online measurement device, characterized in that, include: Open container, piston, and measuring module; The piston is disposed inside the open container and contacts the inner wall of the open container to form a sealed space, which is pre-filled with a known gas. The piston is connected to one end of the movable rod, and a fixed rod is installed at the open container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position. The measuring module is housed within a sealed space, and the measuring module is used for: The pressure and temperature data of the known gas in the sealed space are obtained, and the volume of the sealed gas is calculated based on the ideal gas law. Then, the displacement and tension of the piston are obtained, that is, the deformation and traction force of the piston are measured at the same time.

2. The nerve traction and online measurement device as described in claim 1, characterized in that, In the measurement module, the process of calculating the tension on the piston includes: Based on the proportional relationship between the initial working pressure and the initial working temperature, the pressure correction coefficient is determined by calculating the temperature difference between the working end temperature and the initial working temperature to correct the pressure. The pressure difference between the two sides of the piston is calculated using the corrected pressure, and then combined with the effective contact area between the piston and the sealing gas, the pressure difference between the two sides of the piston is obtained. Calculate the difference between the pressure difference on both sides of the piston and the difference in friction to obtain the tension force on the piston.

3. The nerve traction and online measurement device as described in claim 1 or 2, characterized in that, The piston is fitted with at least one sealing ring on its outer side, and the sealing ring is in contact with the inner wall of the sealing container.

4. The nerve traction and online measurement device as described in claim 3, characterized in that, In the process of calculating the tension on the piston by the measurement module, a friction correction coefficient is also introduced to correct the friction force; the friction correction coefficient is obtained based on the dynamic and static friction conversion curve between the sealing ring and the inner wall of the sealing container.

5. The nerve traction and online measurement device as described in claim 1, characterized in that, The movable rod is connected to the distal end of the severed nerve through a first fixed aperture.

6. The nerve traction and online measurement device as described in claim 1, characterized in that, The fixing rod is connected to the proximal end of the severed nerve through a second fixing hole.

7. The nerve traction and online measurement device as described in claim 1, characterized in that, The sealed space is pre-filled with one or more uniformly mixed gases.

8. The nerve traction and online measurement device as described in claim 1, characterized in that, The sealed space is also connected to a suction pipe via a connector to extract gas from the sealed space, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

9. A nerve traction and online measurement device, characterized in that, include: Sealed container, piston, and measuring module; The piston is disposed inside the sealed container, which initially divides the sealed container into two identical sealed spaces; each sealed space is equipped with a measuring module; the two sealed spaces are pre-filled with the same known gas; The piston is connected to one end of the movable rod, and a fixed rod is installed at the sealed container position opposite to the movable rod. When the movable rod moves a set distance away from the air pressure balance position away from the fixed rod, the movable rod is connected to the distal end of the severed nerve, and the fixed rod is connected to the proximal end of the severed nerve, so as to stretch the severed nerve by using the force of the movable rod gradually returning to the air pressure balance position. The measurement module described herein is used to: acquire pressure and temperature data of known gases in two sealed spaces, and then calculate the volume change of the sealed gas based on the ideal gas law, thereby obtaining the displacement and tension of the piston, i.e., simultaneously measuring the deformation and traction force of the piston.

10. The nerve traction and online measurement device as described in claim 9, characterized in that, The piston is fitted with at least one sealing ring on its outer side, and the sealing ring is in contact with the inner wall of the sealing container.

11. The nerve traction and online measurement device as described in claim 9, characterized in that, The movable rod is connected to the distal end of the severed nerve through a first fixed aperture.

12. The nerve traction and online measurement device as described in claim 9, characterized in that, The fixing rod is connected to the proximal end of the severed nerve through a second fixing hole.

13. The nerve traction and online measurement device as described in claim 9, characterized in that, The sealed container is pre-filled with one or more uniformly mixed gases.

14. The nerve traction and online measurement device as described in claim 9, characterized in that, The sealed space near the fixed rod is also connected to the air extraction pipe via a connector to extract gas from the sealed space, thereby changing the air pressure balance position of the movable rod and achieving the purpose of continuing to stretch the nerve.

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