Unlocking release mechanism and load separation release method

Abstract

The present invention discloses an unlocking and releasing mechanism and a load separation and releasing method, which relate to the technical field of unlocking and releasing devices. The unlocking and releasing mechanism includes a shell body, a back cover, a heating component and a guide sleeve; the shell body includes a main body and a separation part that are interconnected and designed as an integrated whole, the main body is sealed with the back cover and a first chamber is formed inside, and an annular groove is provided on the outer periphery of the first chamber near the separation part; the heating component is arranged in the back cover and connected to the terminal on the back cover, and the heating component is used to provide heat for the phase change medium to undergo gasification phase change; the guide sleeve is sleeved at the connection between the main body and the separation part, and when the separation part is separated from the main body, a second chamber connected to the first chamber is formed between the main body and the separation part. The present invention uses phase change medium as a power source, which reduces the impact and damage to electronic components, precision equipment or their installation platforms in the load, while avoiding environmental pollution.

Description

Technical Field

[0001] The present invention belongs to the technical field of unlocking and releasing devices, and in particular relates to a non-explosive transient separation unlocking and releasing mechanism and a load separation and releasing method. Background Art

[0002] In the fields of aerospace, shipbuilding, etc., the unlocking and releasing mechanism is mainly responsible for locking and unlocking the release load. Explosive bolts, as the most commonly used unlocking and releasing mechanism, mainly rely on explosion or combustion to drive the structure to unlock and release the load.

[0003] Currently, explosive bolts are typically pre-filled with high explosives, which generate an explosive shock that unlocks and releases the load. The higher the mass of the load carried by the explosive bolt, the greater the unlocking force required to release it, and the greater the amount of high explosives required. While the explosive shock does not directly damage the attached load, it can impact and damage sensitive electronic components, precision equipment, or their mounting platforms, impacting stable operation. Furthermore, because explosive bolts are filled with high explosives, they present risks during production, storage, and transportation, and explosions can produce toxic gases that pollute the environment. Summary of the Invention

[0004] The purpose of the present invention is to provide an unlocking and releasing mechanism and a load separation and releasing method to solve the problem that traditional explosive bolts use high explosives to unlock and release the load, which may cause impact on electronic components, precision equipment or their installation platforms inside the load, and produce toxic gases to pollute the environment.

[0005] The present invention solves the above technical problems through the following technical solutions: an unlocking and releasing mechanism, comprising:

[0006] The shell body comprises a main body portion and a separation portion which are connected to each other and designed as an integral whole, a first chamber is provided in the main body portion, and an annular groove is provided on the outer periphery of the first chamber near the separation portion;

[0007] a rear cover connected to the main body to seal the first chamber; a terminal and a valve for injecting a phase change medium into the first chamber are provided on the rear cover;

[0008] a heating component disposed in the first chamber and connected to the terminal, the heating component being used to provide heat for the phase change medium to undergo a gasification phase change;

[0009] and a guide sleeve which is sleeved on the connection between the main body and the separation portion. When the separation portion is separated from the main body, a second chamber communicating with the first chamber is formed between the main body and the separation portion.

[0010] Furthermore, a first thread is provided on the outer periphery of the rear cover, a second thread is provided on the inner wall of the main body, the rear cover and the main body are connected through the first thread and the second thread, and a seal is provided between the rear cover and the main body.

[0011] Furthermore, the heating component includes a tube body filled with a heating agent and an ignition device provided in the tube body, and the ignition device is connected to the terminal.

[0012] Furthermore, the valve is a one-way valve.

[0013] Furthermore, the phase change medium is liquid or solid carbon dioxide, ethane, tetrafluoroethane, nitrogen, chloromethane or dichloromethane.

[0014] Furthermore, during design, the cross-sectional area of the main body at the annular groove satisfies the following conditions:

[0015] ;

[0016] in, Indicates the cross-sectional area of the main body at the annular groove, represents the load mass, represents the acceleration due to gravity, Indicates the safety factor when the separation part bears the load, Indicates the yield strength of the material at the annular groove.

[0017] Based on the same concept, the present invention also provides a load separation and release method using the unlocking and releasing mechanism described above, comprising:

[0018] Determine the critical pressure based on the load mass and unlocking force;

[0019] Determining parameters of a phase change medium and a heat generating component within an unlocking and releasing mechanism based on the critical pressure;

[0020] Arrange the heating component in the back cover according to the parameters of the heating component, and connect the back cover to the main body;

[0021] injecting a phase change medium into the main body according to the parameters of the phase change medium;

[0022] connecting a load to a disconnect portion of the unlocking release mechanism;

[0023] Heat is generated by the heating component, the phase change medium absorbs the heat and undergoes a gasification phase change, the pressure inside the main body increases, and the annular groove breaks under the action of pressure and load, realizing the separation and release of the load.

[0024] Furthermore, the calculation formula of the critical pressure is:

[0025] ;

[0026] in, represents the critical pressure, Indicates the unlocking force, represents the load mass, represents the acceleration due to gravity, represents the inner cross-sectional area of the first chamber at the annular groove.

[0027] Furthermore, based on the critical pressure, the parameters of the phase change medium and the heating component in the unlocking and releasing mechanism are determined, specifically including:

[0028] Constructing a finite element model of the unlocking and releasing mechanism according to the geometric dimensions and material properties of the unlocking and releasing mechanism;

[0029] Based on the finite element model, parameters of the phase change medium and the heating component are set to obtain a simulation model of the unlocking and releasing mechanism;

[0030] Based on the simulation model, a simulation calculation of the expansion work of the phase change medium is performed to obtain the pressure inside the main body at the end of the release;

[0031] Determine whether the pressure in the main body at the end of release is greater than or equal to the critical pressure:

[0032] If so, the corresponding parameters of the phase change medium and heating component are output;

[0033] If not, the simulation model is updated by changing the parameters of the phase change medium and the heating component, and the phase change medium expansion work simulation calculation is performed based on the updated simulation model until the pressure in the main body at the end of the release stage is greater than or equal to the critical pressure.

[0034] Furthermore, the expansion work simulation calculation of the phase change medium includes expansion work simulation calculations in the waiting-for-excitation stage, the waiting-for-release stage, the release stage and the release end stage;

[0035] The expansion work simulation calculation formula in the waiting stage is:

[0036] ;

[0037] ;

[0038] in, Indicates the pressure of the phase change medium in the main body during the exciting stage, represents the specific internal energy of the phase change medium in the main body during the exciting stage, Indicates the density of the phase change medium in the main body during the exciting stage, Indicates the temperature of the phase change medium in the main body during the exciting stage, Indicates the mass of the phase change medium in the main body during the exciting stage, Indicates the volume of the main body. represents REFPROP function, PCM represents phase change medium;

[0039] The expansion work simulation calculation formula in the release stage is:

[0040] ;

[0041] , ;

[0042] , , , ;

[0043] , ;

[0044] in, Indicates the temperature of the phase change medium in the main body during the release phase. Indicates the pressure of the phase change medium in the main body during the release stage. Indicates the specific internal energy of the phase change medium in the main body during the release stage, Indicates the density of the phase change medium in the main body during the release phase. represents the internal energy of the phase change medium in the main body during the release phase, Indicates the mass of the phase change medium in the main body during the release phase. Indicates the ratio coefficient of the heating agent in the heating component to the gas. Indicates the instantaneous mass of the gas products during combustion, represents the internal energy of the phase change medium in the main body during the exciting stage, Indicates the ratio of heat release and absorption value of the heating agent in the heating component. Indicates the instantaneous release of heat in the main body during combustion. Indicates the axial burning velocity of the heating agent in the heating component. represents the empirical constant, n represents the burning rate pressure index, Indicates the mass of the heating agent in the heating component in the waiting stage. Indicates the number of burning surfaces. Indicates the density of the heating agent in the heating component during combustion. represents the cross-sectional area or combustion area of the heating agent in the heating component, t represents the time, Indicates the calorific value of the heating agent in the heating component during combustion;

[0045] The expansion work simulation calculation formula during the release phase is:

[0046] ;

[0047] ;

[0048] , ;

[0049] , ;

[0050] ;

[0051] ;

[0052] in, represents the energy discharged from the first chamber to the second chamber during the release phase, represents the specific enthalpy of the phase change medium in the main body during the release phase, Indicates the temperature of the phase change medium in the main body during the release phase, Indicates the pressure of the phase change medium in the main body during the release phase, represents the specific internal energy of the phase change medium in the main body during the release phase, represents the density of the phase change medium in the main body during the release phase, represents the internal energy of the phase change medium in the main body during the release phase, Indicates the mass of the phase change medium in the main body during the release phase, represents the injection mass flow rate of the main body during the release phase, Indicates the flow correction coefficient, Indicates the effective discharge area, is equal to the inner cross-sectional area of the first chamber at the annular groove, represents the gas constant, represents the specific heat ratio of the phase change medium, Indicates the pressure inside the main body during the release phase. Represents Related constants;

[0053] The expansion work simulation calculation formula at the end of release is:

[0054] ;

[0055] ;

[0056] , ;

[0057] , ;

[0058] , , ;

[0059] ;

[0060] in, It represents the energy discharged from the first chamber to the second chamber at the end of the release. represents the specific enthalpy of the phase change medium in the first chamber at the end of the release phase, represents the temperature of the phase change medium in the first chamber at the end of the release period, represents the pressure of the phase change medium in the first chamber at the end of the release phase, represents the specific internal energy of the phase change medium in the first chamber at the end of the release period, represents the internal energy of the phase change medium in the first chamber at the end of the release phase, represents the mass of the phase change medium in the first chamber at the end of the release period, represents the density of the phase change medium in the first chamber at the end of the release stage, represents the injection mass flow rate between the first chamber and the second chamber at the end of the release phase, represents the specific enthalpy of the outflow mass between the first chamber and the second chamber, Indicates the pressure in the second chamber at the end of the release phase, represents the specific enthalpy in the second chamber at the end of the release phase, Indicates the pressure value at the high-pressure end between the first chamber and the second chamber, Indicates the pressure value at the low-pressure end between the first chamber and the second chamber, Indicates the temperature value of the high-pressure end between the first chamber and the second chamber, Indicates the temperature in the second chamber at the end of the release.

[0061] Compared with the prior art, the advantages of the present invention are:

[0062] The unlocking and releasing mechanism of the present invention uses a phase change medium as a power source, and the separation shock wave generated is much smaller than the shock wave generated by the explosion of high explosives, reducing the impact and damage to the electronic components, precision equipment or their installation platforms inside the load. At the same time, no harmful gases are generated during the separation and release process, avoiding environmental pollution.

[0063] The position of the annular groove of the present invention is controllable. By rationally designing the size of the annular groove, it is ensured that after the pressure of the phase change medium increases sharply due to expansion work, the annular groove is broken, thereby achieving load separation and release.

[0064] The unlocking and releasing mechanism of the present invention has a simple structure and low manufacturing cost, and does not require special processing equipment and processes for production, thereby ensuring the economy and safety of its application, and has good application prospects and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0066] Figure 1 is a three-dimensional view of an unlocking and releasing mechanism according to an embodiment of the present invention;

[0067] Figure 2 This is an exploded view of the structure of the unlocking and releasing mechanism in an embodiment of the present invention;

[0068] Figure 3 is a cross-sectional schematic diagram of an unlocking and releasing mechanism according to an embodiment of the present invention;

[0069] Figure 4 is a schematic cross-sectional view of the embodiment of the present invention when the main body and the separation portion are separated;

[0070] Figure 5 is a schematic cross-sectional view of a shell body according to an embodiment of the present invention;

[0071] Figure 6 is a schematic structural diagram of a back cover in an embodiment of the present invention;

[0072] Figure 7 It is a flow chart of the load separation and release method in an embodiment of the present invention.

[0073] Explanation of the accompanying drawings: 1-shell body, 11-main body, 111-first chamber, 112-second chamber, 12-separation part, 121-third thread, 13-annular groove, 14-second thread, 2-back cover, 21-valve, 22-terminal, 23-first mounting hole, 24-second mounting hole, 3-heating component, 4-seal, 10-guide sleeve. DETAILED DESCRIPTION

[0074] The following is a clear and complete description of the technical solutions of the present invention in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts are within the scope of protection of the present invention.

[0075] The following specific embodiments are used to describe the technical solution of the present application in detail. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0076] Example 1

[0077] Traditional explosive bolts use high explosives as a power source to unlock and release the load. The explosion or combustion of high explosives generates transient, high-frequency, high-vibration shock waves, which can impact and damage electronic components, precision equipment, or their mounting platforms within the load, while also producing toxic gases that pollute the environment. To address the above technical issues, an embodiment of the present invention provides an unlocking and release mechanism that uses a phase-change medium as a power source. The separation shock waves generated during the vaporization phase change of the phase-change medium are much smaller than those generated by the explosion of high explosives, reducing the impact and damage to electronic components, precision equipment, or their mounting platforms within the load, while also preventing the generation of toxic gases.

[0078] like Figures 1 to 6 As shown, the unlocking and releasing mechanism provided by the embodiment of the present invention includes a shell body 1, a back cover 2, a heating component 3 and a guide sleeve 10; the shell body 1 includes a main body 11 and a separation portion 12 that are interconnected and designed as an integrated whole. The main body 11 is sealed with the back cover 2 and has a first chamber 111 formed therein. An annular groove 13 is provided on the outer periphery of the first chamber 111 near the separation portion 12. The separation portion 12 is used to mount a load. A third thread 121 is provided on the outer periphery of the separation portion 12. The load is connected to the separation portion 12 via the third thread 121 and is mounted axially on the separation portion 12. A terminal 22 and a valve 21 for injecting a phase change medium into the first chamber 111 are provided on the back cover 2; the heating component 3 is disposed in the first chamber 111 and is connected to the terminal 22. The heating component 3 is used to provide heat for the phase change medium to undergo a gasification phase change. In this embodiment, the heating component 3 is fixed to the back cover 2 by a support rod. The guide sleeve 10 is sleeved on the connection between the main body 11 and the separation portion 12. When the separation portion 12 is separated from the main body 11, a second chamber 112 communicating with the first chamber 111 is formed between the main body 11 and the separation portion 12. Figure 4 As shown, the guide sleeve 10 is the side wall of the second chamber.

[0079] The specific process of realizing load separation and release by using the unlocking and releasing mechanism in the embodiment of the present invention is as follows: a phase change medium is injected into the first chamber 111 through the valve 21, a large amount of heat is generated through the heating component 3, the phase change medium absorbs the heat and undergoes a gasification phase change, so that high pressure is generated in the first chamber 111, the annular groove 13 breaks under the action of high pressure and load, and the separation part 12 continues to slide outward along the guide sleeve 10 under the action of high pressure, so that the main body 11 and the separation part 12 are separated, and a second chamber 112 is formed between the main body 11 and the separation part 12, thereby realizing load separation and release.

[0080] The annular groove 13 is the breaking point during separation and release. The annular groove 13 is coaxial with the main body 11, and the location of the annular groove 13 is controllable. The size of the annular groove 13 is set according to the load and the material properties of the shell body 1. In the specific implementation of this embodiment, the cross-sectional area of the main body 11 at the annular groove 13 meets the following conditions:

[0081] (1);

[0082] in, represents the cross-sectional area of the main body 11 at the annular groove 13, represents the load mass, represents the acceleration due to gravity, It represents the safety factor when the separation part 12 bears the load, It represents the yield strength of the material at the annular groove 13, that is, the yield strength of the material of the shell body.

[0083] In a specific embodiment of the present invention, Figure 5 As shown, a first thread is provided on the outer periphery of the back cover 2, and a second thread 14 is provided on the inner wall of the main body 11. The back cover 2 and the main body 11 are connected through the first thread and the second thread 14, and a seal 4 is provided between the back cover 2 and the main body 11 to improve the sealing performance of the first chamber 111.

[0084] In a specific embodiment of the present invention, the heating component 3 includes a tube body filled with a heating agent and an ignition device provided in the tube body, and the ignition device is connected to the terminal 22.

[0085] The ignition device is connected to an external excitation power supply through the terminal 22. The excitation power supply sends an excitation current to the ignition device. The ignition device ignites the heating agent, which generates a large amount of heat. The phase change medium that absorbs the heat undergoes a gasification phase change, causing the pressure in the first chamber 111 to increase, thereby increasing the pressure acting on the annular groove 13, causing a fracture at the annular groove 13.

[0086] like Figure 6 As shown, the rear cover 2 is provided with a first mounting hole 23 and a second mounting hole 24. The first mounting hole 23 is used to mount the valve 21, and the second mounting hole 24 is used to mount the terminal posts 22. The terminal posts 22 may be one or more groups, with each group of terminal posts 22 corresponding to an ignition device. In this embodiment, the terminal posts 22 are made of metal and are coated with a layer of polytetrafluoroethylene to provide insulation and sealing between the terminal posts 22 and the rear cover 2.

[0087] In this embodiment, the valve 21 is a one-way valve, through which a phase change medium is injected into the main body 11. The phase change medium in this embodiment is liquid or solid carbon dioxide, ethane, tetrafluoroethane, nitrogen, chloroform or dichloromethane.

[0088] Example 2

[0089] like Figure 7 As shown, an embodiment of the present invention provides a load separation and release method using the unlocking and releasing mechanism in the first embodiment of the present invention, comprising the following steps:

[0090] Step 1: Determine the critical pressure based on the load mass and the unlocking force.

[0091] The unlocking force required to achieve load separation and release by breaking the annular groove is determined by the size and material properties of the annular groove. The specific calculation formula is:

[0092] (2);

[0093] in, Indicates the unlocking force, It represents the dynamic load coefficient under load, Indicates the tensile strength of the material at the annular groove, Indicates the cross-sectional area of the main body at the annular groove.

[0094] The critical pressure refers to the pressure in the main body (or first chamber) when the annular groove breaks. The specific calculation formula for the critical pressure is:

[0095] (3);

[0096] in, represents the critical pressure, Indicates the unlocking force, represents the load mass, represents the acceleration due to gravity, represents the inner cross-sectional area of the first chamber at the annular groove.

[0097] Step 2: Based on the critical pressure, determine the parameters of the phase change medium and the heat generating components in the unlocking release mechanism.

[0098] In a specific embodiment of the present invention, the parameters of the phase change medium and the heating component in the unlocking and releasing mechanism are determined by simulation, specifically including:

[0099] Step 2.1: Construct a finite element model of the unlocking and releasing mechanism based on its geometric dimensions and material properties;

[0100] Step 2.2: Based on the finite element model, set the parameters of the phase change medium and the heating component to obtain a simulation model of the unlocking and releasing mechanism;

[0101] Step 2.3: Based on the simulation model, perform a simulation calculation of the expansion work of the phase change medium to obtain the pressure in the main body (i.e., the first chamber) at the end of the release phase;

[0102] Step 2.4: Determine whether the pressure in the main body at the end of the release phase is greater than or equal to the critical pressure:

[0103] If so, the corresponding parameters of the phase change medium and heating component are output;

[0104] If not, update the simulation model by changing the parameters of the phase change medium and the heating component, and then go to step 2.3.

[0105] In step 2.3, the expansion work process of the phase change medium is divided into the waiting stage (i.e., the stage before the heat generating component generates heat), the waiting stage (the stage when the heat generating component generates heat and the phase change medium is waiting to be vaporized and undergoes phase change), the release stage (the stage when the phase change medium is vaporized and undergoes phase change), and the release end stage. Therefore, the simulation calculation of the expansion work of the phase change medium includes the expansion work simulation calculations in the waiting stage, the waiting stage, the release stage, and the release end stage.

[0106] Based on the actual physical properties of the phase change medium at each stage and the phase change theory of the phase change medium, a simulation calculation formula for the expansion work at each stage is constructed. This embodiment uses liquid carbon dioxide as the phase change medium as an example. The actual physical properties of carbon dioxide can be obtained by referencing the actual physical property database of the National Institute of Standards and Technology (NIST). The REFPROP software (or function) developed by NIST is used as an interface to obtain the actual physical property data. Specifically, REFPROP is used to query the corresponding other intensity quantities using two intensity quantities (i.e., quantities whose properties are independent of the amount of the substance, such as pressure, temperature, specific internal energy, specific enthalpy, density, etc.) and a specified substance symbol, namely:

[0107] (4);

[0108] in, 、 Represent the known thermodynamic physical property strength quantities, represents the intensity of other thermodynamic properties to be determined, Represents the REFPROP function, Indicates the symbol of matter.

[0109] During the waiting stage, carbon dioxide is stored in the first chamber at room temperature and high density. Based on the relevant parameters of the first chamber at this stage, the pressure and specific internal energy of carbon dioxide in the first chamber can be obtained by querying based on formula (4). Therefore, the expansion work simulation calculation formula during the waiting stage is:

[0110] (5);

[0111] (6);

[0112] in, Indicates the pressure of the phase change medium in the first chamber (i.e. the main body) during the exciting stage. represents the specific internal energy of the phase change medium in the first chamber during the exciting stage, represents the density of the phase change medium in the first chamber during the exciting stage, represents the temperature of the phase change medium in the first chamber during the exciting stage, represents the mass of the phase change medium in the first chamber during the exciting stage, represents the volume of the first chamber.

[0113] The exothermic agent in the heating component is ignited by the external excitation current and begins to burn, releasing heat and combustion gas products into the first chamber, entering the waiting release stage. The calculation formula for the instantaneous mass of the gas products and the instantaneous heat released during combustion is:

[0114] (7);

[0115] (8);

[0116] in, Indicates the instantaneous mass of the gas products during combustion, Indicates the instantaneous release of heat in the first chamber during combustion. Indicates the axial burning velocity of the heating agent in the heating component. Indicates the number of burning surfaces. Indicates the density of the heating agent in the heating component during combustion (unit: kg / m 3 ), Indicates the cross-sectional area or combustion area of the heating agent in the heating component (unit: m 2 ), t represents time, Indicates the calorific value of the heating agent in the heating component during combustion (unit: kJ / m 3 ). After the heating agent is ignited, it burns along the axis. The surface where the burning moves after being ignited is the burning surface. For example, if the heating agent starts to burn from the middle, it will move from the middle point to both sides, and there will be two burning surfaces.

[0117] The calculation formula for the mass and internal energy in the first chamber during the release phase is:

[0118] (9);

[0119] , (10);

[0120] in, Indicates the mass of carbon dioxide in the first chamber during the release phase. Indicates the ratio coefficient of the heat-generating agent in the heating component to gas (usually 0.6~0.7). represents the internal energy of the carbon dioxide in the first chamber during the release phase, represents the internal energy of carbon dioxide in the first chamber during the waiting period for excitation, Indicates the ratio of the exothermic absorption value of the heating agent in the heating component (usually 0.6~0.95, which can be accurately calibrated through combustion tests) ).

[0121] Axial burning velocity of the exothermic agent The Vieille burning rate law with a wide pressure application range is used, and the specific calculation formula is:

[0122] (11);

[0123] in, represents the empirical constant, n represents the burning rate pressure index, Indicates the pressure of carbon dioxide in the first chamber during the release phase, Indicates the mass of the exothermic agent in the stage to be excited. The burning rate pressure index n can be accurately calibrated through combustion tests. In the waiting release stage, the density in the first chamber is , specific internal energy Increase, temperature and pressure Continuously improve, the calculation formula of density and specific internal energy is:

[0124] , (12);

[0125] The density , specific internal energy As the intensity value, substitute it into formula (13) and query the temperature inside the main body at this time through REFPROP and pressure :

[0126] (13);

[0127] The high-pressure carbon dioxide mixture is released from the first chamber and enters the release stage. The effective discharge area is set to , That is, the inner cross-sectional area of the first chamber at the annular groove , the calculation formula of the injection mass flow rate of the first chamber is:

[0128] (14);

[0129] (15);

[0130] in, represents the injection mass flow rate of the first chamber during the release phase, Indicates the flow correction coefficient, represents the pressure of carbon dioxide in the first chamber during the release phase, represents the temperature of carbon dioxide in the first chamber during the release phase, represents the gas constant, represents the specific heat ratio of carbon dioxide, represents the pressure in the first chamber during the release phase, Represents Related constants. Flow correction factor The ratio of actual flow rate to theoretical flow rate can be selected within the range of 0.85 to 0.95 based on test results or experience. The mass in the first chamber during the release phase is:

[0131] (16);

[0132] in, represents the mass of carbon dioxide in the first chamber during the release phase. Assuming that the carbon dioxide ejection is an isentropic flow, the internal energy of the first chamber during the release phase is equal to the initial internal energy plus the heat released by the combustion of the exothermic agent, minus the outflow energy:

[0133] (17);

[0134] in, represents the internal energy of carbon dioxide in the first chamber during the release phase, Indicates the specific enthalpy of carbon dioxide in the first chamber during the release phase (unit: kJ / kg, which can be queried using the REFPROP function). ,temperature You can query it by combining the REFPROP function with the intensity quantity:

[0135] (18);

[0136] , (19);

[0137] in, represents the specific internal energy of carbon dioxide in the first chamber during the release phase, It represents the density of carbon dioxide in the first chamber during the release phase. and injection mass flow rate Calculate the energy discharged from the first chamber during the release phase :

[0138] (20);

[0139] At the end of the release phase, the carbon dioxide pressure in the first chamber and the pressure in the second chamber reach a basic balance, and the flow rate approaches 0. Therefore, the mathematical model of the end of the release phase is:

[0140] (twenty one);

[0141] (twenty two);

[0142] , (twenty three);

[0143] , (twenty four);

[0144] (25);

[0145] (26);

[0146] in, It represents the energy discharged from the first chamber to the second chamber at the end of the release. represents the specific enthalpy of the phase change medium in the first chamber at the end of the release phase, represents the temperature of the phase change medium in the first chamber at the end of the release period, represents the pressure of the phase change medium in the first chamber at the end of the release phase, represents the specific internal energy of the phase change medium in the first chamber at the end of the release period, represents the internal energy of the phase change medium in the first chamber at the end of the release phase, represents the mass of the phase change medium in the first chamber at the end of the release period, represents the density of the phase change medium in the first chamber at the end of the release stage, represents the injection mass flow rate between the first chamber and the second chamber at the end of the release phase, represents the specific enthalpy of the outflow mass between the first chamber and the second chamber, Indicates the pressure in the second chamber at the end of the release phase, represents the specific enthalpy in the second chamber at the end of the release phase, Indicates the pressure value at the high-pressure end between the first chamber and the second chamber, Indicates the pressure value at the low-pressure end between the first chamber and the second chamber, Indicates the temperature value of the high-pressure end between the first chamber and the second chamber, Indicates the temperature in the second chamber at the end of the release.

[0147] The quality of the phase change medium can be determined by steps 2.1 to 2.4. And the quality of the heating agent in the heating component , Number of burning surfaces and cross-sectional area , according to the quality of the phase change medium Inject phase change medium into the first chamber, according to the mass of the heating agent , Number of burning surfaces and cross-sectional area Set up the heating component.

[0148] In another specific embodiment of the present invention, the parameters of the phase change medium and the heat generating component in the unlocking and releasing mechanism are determined by testing. Specifically, a heat generating component is set in the back cover, the phase change medium is injected into the main body, and a load separation and release test is performed using the unlocking and releasing mechanism. During the test, the pressure in the first chamber is monitored. If the maximum monitored pressure is less than the critical pressure and load separation and release is not achieved, the mass of the phase change medium and the parameters of the heat generating agent are changed, and the test is repeated until the maximum monitored pressure is greater than or equal to the critical pressure and load separation and release is achieved, thereby determining the mass of the phase change medium and the parameters of the heat generating agent.

[0149] Step 3: Set the heating component in the back cover according to the parameters of the heating component, and connect the back cover to the main body.

[0150] A heating component is arranged in the rear cover according to the parameters of the heating agent determined in step 2, and the rear cover is connected to the main body to seal the first chamber.

[0151] Step 4: Inject the phase change medium into the main body according to the parameters of the phase change medium.

[0152] According to the mass of the phase change medium, the phase change medium is injected into the main body (ie, the first chamber) through the valve.

[0153] Step 5: Connect the load to the disconnect portion of the unlocking release mechanism.

[0154] The unlocking and releasing mechanism is installed in the protective frame, and the load is mounted along the axial direction of the separation part to realize the connection between the load and the separation part.

[0155] Step 6: Heat is generated by the heating component, the phase change medium absorbs the heat and undergoes a gasification phase change, the pressure inside the main body increases, the annular groove breaks under the action of pressure and load, and the separation part continues to slide outward along the guide sleeve under the action of high pressure, separating the main body from the separation part, forming a second chamber between the main body and the separation part, thereby realizing the separation and release of the load.

[0156] An external excitation power source is connected via a terminal, and the excitation power source sends an excitation current to the ignition device, which ignites the heat-generating agent. The heat-generating agent generates a large amount of heat, and the phase change medium that absorbs the heat undergoes a gasification phase change, which increases the pressure in the first chamber, thereby increasing the pressure acting on the annular groove, causing the annular groove to fracture, thereby achieving load separation and release. In actual tests, the edge of the fracture showed instantaneous fracture marks, and no obvious large debris was missing at the fracture. The main body and the separation part after separation were both intact in appearance, with no parts missing or damaged. This shows that the test results of the present invention are consistent with the design scheme and can be promoted for practical use.

[0157] The above disclosure is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or modifications within the technical scope disclosed in the present invention, and they should all be covered by the scope of protection of the present invention.

Claims

1. A load separation and release method using an unlocking and releasing mechanism, characterized in that: The unlocking and releasing mechanism includes a shell body, a back cover, a heating component, and a guide sleeve. The shell body includes a main body and a separation part that are interconnected and integrally designed. A first chamber is provided in the main body, and an annular groove is provided on the outer periphery of the first chamber near the separation part; the back cover is connected to the main body to seal the first chamber; a terminal and a valve for injecting a phase change medium into the first chamber are provided on the back cover; the heating component is provided in the first chamber and connected to the terminal, and the heating component is used to provide heat for the phase change medium to undergo a gasification phase change; the guide sleeve is sleeved at the connection between the main body and the separation part. When the separation part is separated from the main body, a second chamber communicating with the first chamber is formed between the main body and the separation part; the method includes: Determine the critical pressure based on the load mass and unlocking force; Determining parameters of a phase change medium and a heat generating component within an unlocking and releasing mechanism based on the critical pressure; Arrange the heating component in the back cover according to the parameters of the heating component, and connect the back cover to the main body; injecting a phase change medium into the main body according to the parameters of the phase change medium; connecting a load to a disconnect portion of the unlocking release mechanism; Heat is generated by the heating component, and the phase change medium absorbs the heat and undergoes a gasification phase change. The pressure inside the main body increases, and the annular groove breaks under the action of pressure and load, achieving load separation and release; Wherein, based on the critical pressure, the parameters of the phase change medium and the heating component in the unlocking and releasing mechanism are determined, specifically including: Constructing a finite element model of the unlocking and releasing mechanism according to the geometric dimensions and material properties of the unlocking and releasing mechanism; Based on the finite element model, parameters of the phase change medium and the heating component are set to obtain a simulation model of the unlocking and releasing mechanism; Based on the simulation model, a simulation calculation of the expansion work of the phase change medium is performed to obtain the pressure inside the main body at the end of the release; Determine whether the pressure in the main body at the end of release is greater than or equal to the critical pressure: If so, the corresponding parameters of the phase change medium and heating component are output; If not, the simulation model is updated by changing the parameters of the phase change medium and the heating component, and the phase change medium expansion work simulation calculation is performed based on the updated simulation model until the pressure in the main body at the end of the release stage is greater than or equal to the critical pressure.

2. The load separation and release method according to claim 1, characterized in that: A first thread is provided on the outer periphery of the rear cover, a second thread is provided on the inner wall of the main body, the rear cover and the main body are connected through the first thread and the second thread, and a seal is provided between the rear cover and the main body.

3. The load separation and release method according to claim 1, characterized in that: The heating component includes a tube body filled with a heating agent and an ignition device arranged in the tube body, and the ignition device is connected to the terminal.

4. The load separation and release method according to claim 1, characterized in that: The valve is a one-way valve.

5. The load separation and release method according to claim 1, characterized in that: The phase change medium is liquid or solid carbon dioxide, ethane, tetrafluoroethane, nitrogen, methyl chloride or dichloromethane.

6. The load separation and release method according to any one of claims 1 to 5, characterized in that: During design, the cross-sectional area of the main body at the annular groove meets the following conditions: ； in, Indicates the cross-sectional area of the main body at the annular groove, represents the load mass, represents the acceleration due to gravity, Indicates the safety factor when the separation part bears the load, Indicates the yield strength of the material at the annular groove.

7. The load separation and release method according to claim 1, characterized in that: The calculation formula of the critical pressure is: ； in, represents the critical pressure, Indicates the unlocking force, represents the load mass, represents the acceleration due to gravity, represents the inner cross-sectional area of the first chamber at the annular groove.

8. The load separation and release method according to claim 1, characterized in that: The expansion work simulation calculation of the phase change medium includes expansion work simulation calculations in the waiting-for-excitation stage, the waiting-for-release stage, the release stage and the release end stage; The expansion work simulation calculation formula in the waiting stage is: ； ； in, Indicates the pressure of the phase change medium in the main body during the exciting stage, represents the specific internal energy of the phase change medium in the main body during the exciting stage, Indicates the density of the phase change medium in the main body during the exciting stage, Indicates the temperature of the phase change medium in the main body during the exciting stage, Indicates the mass of the phase change medium in the main body during the exciting stage, Indicates the volume of the main body. represents REFPROP function, PCM represents phase change medium; The expansion work simulation calculation formula in the release stage is: ； ， ； ， ， ， ； ， ； in, Indicates the temperature of the phase change medium in the main body during the release phase. Indicates the pressure of the phase change medium in the main body during the release stage. Indicates the specific internal energy of the phase change medium in the main body during the release stage, Indicates the density of the phase change medium in the main body during the release phase. represents the internal energy of the phase change medium in the main body during the release phase, Indicates the mass of the phase change medium in the main body during the release phase. Indicates the ratio coefficient of the heating agent in the heating component to the gas. Indicates the instantaneous mass of the gas products during combustion, represents the internal energy of the phase change medium in the main body during the exciting stage, Indicates the ratio of heat release and absorption value of the heating agent in the heating component. Indicates the instantaneous release of heat in the main body during combustion. Indicates the axial burning velocity of the heating agent in the heating component. represents the empirical constant, n represents the burning rate pressure index, Indicates the mass of the heating agent in the heating component in the waiting stage. Indicates the number of burning surfaces. Indicates the density of the heating agent in the heating component during combustion. represents the cross-sectional area or combustion area of the heating agent in the heating component, t represents the time, Indicates the calorific value of the heating agent in the heating component during combustion; The expansion work simulation calculation formula during the release phase is: ； ； ， ； ， ； ； ； in, represents the energy discharged from the first chamber to the second chamber during the release phase, represents the specific enthalpy of the phase change medium in the main body during the release phase, Indicates the temperature of the phase change medium in the main body during the release phase, Indicates the pressure of the phase change medium in the main body during the release phase, represents the specific internal energy of the phase change medium in the main body during the release phase, represents the density of the phase change medium in the main body during the release phase, represents the internal energy of the phase change medium in the main body during the release phase, Indicates the mass of the phase change medium in the main body during the release phase, represents the injection mass flow rate of the main body during the release phase, Indicates the flow correction coefficient, Indicates the effective discharge area, is equal to the inner cross-sectional area of the first chamber at the annular groove, represents the gas constant, represents the specific heat ratio of the phase change medium, Indicates the pressure inside the main body during the release phase. Represents Related constants; The expansion work simulation calculation formula at the end of release is: ； ； ， ； ， ； ， ， ； ； in, It represents the energy discharged from the first chamber to the second chamber at the end of the release. represents the specific enthalpy of the phase change medium in the first chamber at the end of the release phase, represents the temperature of the phase change medium in the first chamber at the end of the release period, represents the pressure of the phase change medium in the first chamber at the end of the release phase, represents the specific internal energy of the phase change medium in the first chamber at the end of the release period, represents the internal energy of the phase change medium in the first chamber at the end of the release phase, represents the mass of the phase change medium in the first chamber at the end of the release period, represents the density of the phase change medium in the first chamber at the end of the release stage, represents the injection mass flow rate between the first chamber and the second chamber at the end of the release phase, represents the specific enthalpy of the outflow mass between the first chamber and the second chamber, Indicates the pressure in the second chamber at the end of the release phase, represents the specific enthalpy in the second chamber at the end of the release phase, Indicates the pressure value at the high-pressure end between the first chamber and the second chamber, Indicates the pressure value at the low-pressure end between the first chamber and the second chamber, Indicates the temperature value of the high-pressure end between the first chamber and the second chamber, Indicates the temperature in the second chamber at the end of the release.

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