Device and method for testing friction force of launch canister

Abstract

The invention relates to a device and a method for testing friction force of a launch canister, and belongs to the field of devices for testing specific target force. A method for testing the friction force of a launch canister comprises the following steps of: vertically placing the launch canister, hoisting a load into the launch canister at a constant speed or taking the load out of the launch canister at a constant speed by using a hoisting mechanism, and measuring the corresponding relationship between the tension of the load and time by using a tension sensor, friction force can be obtained according to the tension and the gravity, a displacement time detection mechanism located in the launch canister is used for detecting the corresponding relation between displacement and time when the load is loaded or unloaded, the corresponding relation between the friction force and the time is obtained according to the tension and the gravity, and finally the friction force corresponds to time in the relation between the friction force and the time and the relation between the displacement and the time. Therefore, a problem that only the relationship between the friction force and the time can be obtained and the influence of each position of the launching canister on the friction force cannot be known in the prior art can be solved.

Description

Technical Field

[0001] The invention relates to a device and method for testing the friction force of a launching tube, belonging to the field of testing devices for specific purpose forces. Background Art

[0002] Cylinder launch is a common form of launch, such as the launch of artillery shells or missiles. During the launch, the load to be launched is ejected outward at high speed from the launch tube along the axis of the launch tube. Generally, in order to facilitate transportation, a limit structure with an interference fit with the load is set in the launch tube. The friction and extrusion force between the load and the limit structure make it difficult for the load to shake in the launch tube. However, in the process of the load being ejected from the launch tube, a large friction force will be generated between the load and the limit structure in the launch tube, affecting the ejection speed and kinetic energy of the load. Therefore, it is crucial to study the friction force during the movement of the load relative to the launch tube.

[0003] Prior to this, the method used by the applicant to test the friction force of the load relative to the launch tube during movement was as follows: Figure 1 As shown, a pulling mechanism is fixedly arranged at the launch port of the launch tube 1, and the pulling mechanism includes a fixed structure fixed at the launch port, a steel wire rope 33 for pulling the head of the load is arranged in the middle of the fixed structure, and a tension sensor 34 is arranged on the steel wire rope 33, and the tension sensor 34 can detect the magnitude of the tension within a certain period of time and output the corresponding relationship between the tension and time. When testing is required, slowly pull the steel wire rope upward to make the load move upward until it is separated from the launch tube. Under the action of the steel wire rope, the load is lifted upward, and the tension sensor can always detect the tension provided on the steel wire rope during the rising process. Since there is friction between the load and the limiting structure of the launch tube, the friction is opposite to the movement direction of the load, so the difference between the tension and gravity of the steel wire rope during the uniform motion is equal to the friction. The gravity of the load is certain, so the friction force of the load during the rising process is equal to the difference between the tension and gravity recorded by the tension sensor, and then the friction force of the load moving upward out of the launch tube is obtained.

[0004] However, in the above technical solution, the data obtained through the measurement of the tension sensor is actually the data of the friction force changing with time. The speed will actually change slightly during the load rising process. Due to the irregular change of speed, the researchers can only obtain the change of friction force with time but cannot know the change of friction force and stroke. In the actual process, the testers hope to obtain the corresponding relationship between friction force and stroke, so as to understand the influence of different positions in the launch tube on friction force during the launching process. Therefore, the researchers hope to synchronously detect the relationship between the displacement of the load in the launch tube and time.

[0005] In the prior art, there are means of detection using photoelectric displacement sensors or electromagnetic wave displacement sensors. These sensors can obtain the change of load with displacement. Since the relationship between displacement and time is known, the speed of the load can actually be calculated, which is of great significance for studying the initial launch speed of the load. When studying the initial launch speed of the load, the load will fly out quickly to approach the target. If the sensor is set on the load, the sensor cannot be retracted. When the load is launched, a large amount of thick smoke and high-temperature gas will be ejected from the bottom of the load, which will make the environment inside the launch tube very harsh, and it is impossible to use optical or sound wave reflection sensors. Summary of the invention

[0006] The object of the present invention is to provide a launch tube friction test device to solve the problem that the launch tube friction test in the prior art can only obtain the relationship between friction and time but cannot understand the influence of various positions of the launch tube on the friction; the object of the present invention is also to provide a launch tube friction test method to solve the above-mentioned technical problems.

[0007] To achieve the above purpose, the friction force testing method of the launch tube in the present invention adopts the following technical scheme: A method for testing the friction of a launch tube comprises the following steps: placing the launch tube vertically, using a lifting mechanism to lift a load and uniformly loading it into the launch tube or removing it from the launch tube, using a tension sensor to measure the corresponding relationship between the tension of the lifting mechanism on the load and time during the movement of the load in the launch tube, using a displacement time detection mechanism located in the launch tube to detect the corresponding relationship between the displacement and time when the load is loaded or removed, obtaining the corresponding relationship between friction and time based on the tension and gravity, and finally making the time in the relationship between friction and time and displacement and time correspond to obtain the corresponding relationship between friction and displacement.

[0008] Furthermore, testing the correspondence between displacement and time includes connecting a flexible rope to the tail of the load, winding the flexible rope around a winding wheel, keeping the winding wheel and the rotor of the encoder moving synchronously, and synchronously driving the winding wheel and the rotor of the encoder to move when the load is emitted, and outputting the displacement and time relationship of the load through the encoder.

[0009] The beneficial effects of the launch tube friction test method of the present invention are as follows: the present invention belongs to a pioneering invention; firstly, the launch tube is placed vertically so that the launch channel of the launch tube is arranged vertically, and a lifting mechanism is used to lift the load and uniformly load it into the launch tube or uniformly remove it from the launch tube so that the load is in a force balance state at this time. When the load is uniformly loaded into the launch tube, the friction force is directed upward, and at this time the friction force is equal to gravity minus the pulling force; when the load is uniformly removed from the launch tube, the friction force is directed downward, and at this time the friction force is equal to the pulling force minus gravity; by using a tension sensor, the corresponding relationship between the pulling force and time can be obtained, and correspondingly, the corresponding relationship between the friction force and time is also obtained, and the corresponding relationship between the displacement and time of the load is obtained by a displacement time detection mechanism. Since the time in the corresponding relationship between the friction force and time and the corresponding relationship between the displacement and time is the same period of time, the corresponding relationship between the friction force and the displacement can be obtained after the time is matched, thereby solving the problem that the launch tube friction test in the prior art can only obtain the relationship between the friction force and time and cannot understand the influence of each position of the launch tube on the friction force.

[0010] In order to achieve the above-mentioned purpose, the launch tube friction force testing device in the present invention adopts the following technical scheme: A launch tube friction force testing device comprises a hoisting mechanism arranged outside the launch tube for hoisting a load into or out of the launch tube, a tension sensor is arranged on the hoisting mechanism for real-time detecting the tension provided by the hoisting mechanism and outputting the corresponding relationship between the tension and time, and also comprises a displacement time detection mechanism for detecting the corresponding relationship between the displacement time when the load escapes from the launch tube.

[0011] Furthermore, the displacement time detection structure includes an assembly body for fixing at the bottom of the launching tube, a winding wheel is rotatably mounted on the assembly body, a flexible rope having one end wound around the winding wheel for connecting to a load, and the displacement time detection mechanism also includes an encoder, and the rotating shaft of the winding wheel and the rotor of the encoder are synchronously connected.

[0012] Furthermore, the assembly body is a closed shell, and a flexible rope through-hole for the flexible rope to pass through is provided on the shell.

[0013] Furthermore, a protection tube for the flexible rope to pass through is also provided on the shell, and the tube opening of the protection tube is connected to the flexible rope through-hole.

[0014] Furthermore, the displacement time detection mechanism also includes a brake for braking the winding wheel so that the flexible rope between the winding wheel and the load is in a straight state when the flexible rope is pulled by the load, and the braking force of the brake is set to be less than 1% of the friction between the load and the launching tube when the load escapes from the launching tube.

[0015] Furthermore, the displacement time detection mechanism also includes a rope arrangement device which is arranged on the outside of the winding wheel and maintains a preset gap with the winding wheel to squeeze the flexible rope so that the flexible rope can be kept in a single layer winding on the winding wheel.

[0016] Furthermore, the rotor of the encoder is fixedly connected to the winding wheel, and the rotation axis of the rotor of the encoder is colinear with the rotation axis of the winding wheel.

[0017] Furthermore, the shell includes a base plate for installation on the launch tube and a protective cover buckled on the base plate, and the flexible rope through hole is arranged on the protective cover.

[0018] Furthermore, the cover opening of the protective cover is provided with a flange folded outward and fitted with the base plate, and the flange and the base plate are provided with fastener mounting holes for fasteners to pass through so as to install the assembly body into the launching tube.

[0019] The beneficial effects of the launch tube friction test device in the present invention are as follows: the present invention belongs to a pioneering invention, and by setting a hoisting mechanism, it is convenient to hoist the load into or out of the launch tube. During the hoisting process, the load will be affected by tension, friction and gravity. When the load force balance is controlled, the other two can be known to obtain another force. By setting a tension sensor on the hoisting mechanism, it is convenient to obtain the corresponding relationship between tension and time. By setting a displacement time detection mechanism, it is convenient to obtain the corresponding relationship between displacement and time. When detecting, the uniform motion is controlled. When the load is uniformly loaded into the launch tube, the friction force is in the upward direction, and the friction force is equal to gravity minus the tension force; when the load is uniformly released from the launch tube, the friction force is in the downward direction, and the friction force is equal to tension minus gravity; because the time in the corresponding relationship between friction and time and the corresponding relationship between displacement and time is the same period of time, the corresponding relationship between friction and displacement can be obtained after the time is matched, thereby solving the problem that the launch tube friction test in the prior art can only obtain the relationship between friction and time and cannot understand the influence of each position of the launch tube on the friction force. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the launch tube friction force testing device previously used by the applicant; Figure 2 It is a structural schematic diagram of a launch tube in the prior art; Figure 3 It is a structural schematic diagram of an embodiment of a launch tube friction force testing device of the present invention; Figure 4 for Figure 3 A partial enlarged view of point A in the middle.

[0021] In the figure: 1. Launch tube; 11. Inspection hole cover; 12. Limiting structure; 13. Support ring; 14. Mounting ring; 2. Load; 31. Gantry hanger; 32. Hoist; 33. Wire rope; 34. Tension sensor; 41. Shell; 42. Winding wheel; 43. Encoder; 44. Pull wire; 45. Protective tube; 46. Brake; 47. Rope guide. DETAILED DESCRIPTION

[0022] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0023] In the present invention, a tension sensor and a displacement time detection mechanism are set to detect the load, and the movement of the load is converted into the movement of the winding wheel and the encoder. Since there is a clear relationship between the tension, friction and gravity when the load moves at a constant speed, the corresponding relationship between friction and time can also be obtained. Since the time is the same period of time, the relationship between displacement and friction can be obtained after the time is matched.

[0024] In the embodiment of the launch tube friction force testing device of the present invention: The matching relationship between the launch tube and the load is as follows: Figure 2 and Figure 3 As shown, the launch tube 1 has a cylindrical shell 41, and a support ring 13 for supporting the load 2 is arranged on the inner wall surface of the launch tube 1. A limiting structure 12 is also arranged on the inner wall of the launch tube 1 and above the support ring 13 to prevent the load 2 from shaking in the launch tube 1 after being loaded into the launch tube 1. The setting of the limiting structure 12 also causes a large friction force to be generated when the load 2 is loaded into or ejected from the launch tube 1. There are often other structures in the launch tube 1, so an inspection hole is also arranged on the outer peripheral wall surface of the launch tube 1. The inspection hole is a draft hole, and a corresponding inspection hole cover 11 is also provided to cover the inspection hole.

[0025] like Figure 3As shown, the launch tube friction force testing device in the present invention includes a hoisting mechanism for being arranged outside the launch tube 1 to hoist the load 2 into or out of the launch tube 1. Specifically, the hoisting mechanism is a gantry crane, which includes a gantry hanger 31 and a hoist 32 arranged on the gantry hanger 31. A wire rope 33 is arranged on the output end of the hoist 32, and the wire rope 33 is used to connect to the load 2 to facilitate the hoisting of the load 2. The output end of the hoist 32 can rotate at a constant speed, thereby controlling the load 2 to move at a constant speed as much as possible. A tension sensor 34 is also arranged on the wire rope 33, and the tension on the load 2 on the wire rope 33 can be detected in real time through the tension sensor 34, and the corresponding relationship between the tension and time is obtained and these corresponding relationships are sent out. The tension sensor 34 is a prior art, and its working principle and specific structure are not repeated here. Of course, in other embodiments, the hoisting mechanism can also be set as an electric hoist or other lifting equipment, as long as it can meet the lifting weight and uniform motion.

[0026] The relationship between friction and time can be obtained by setting the gantry crane and the tension sensor 34. In order to obtain the relationship between friction and displacement, it is also necessary to know the relationship between displacement and time. The launch tube friction test device also needs to include a displacement time detection mechanism. The displacement time detection mechanism can obtain the relationship between displacement and time, which can also reflect the speed of the load 2. The displacement time detection mechanism can include a photoelectric displacement sensor or a non-contact displacement sensor. Through these sensors, the corresponding relationship between displacement and time can be obtained and the ejection speed of the load 2 can also be obtained. However, when the load 2 is ejected, the load 2 will fly out quickly and approach the target. If the sensor is set on the load 2, the sensor cannot be retracted. And when the load 2 is launched, a large amount of thick smoke and high-temperature gas will be sprayed from the bottom of the load 2, which will make the environment in the launch tube 1 very harsh, and optical or acoustic reflection sensors cannot be used. In order to adapt to the special working conditions during the launch, the launch tube friction test device in this embodiment also includes a displacement time detection mechanism arranged at the bottom of the launch tube 1.

[0027] like Figure 3 and Figure 4As shown, the displacement time detection mechanism needs to be set at the bottom of the launch tube 1 during detection. The displacement time detection mechanism includes a shell 41 for being fixedly set at the bottom of the launch tube 1, and a winding wheel 42 is rotatably installed in the shell 41. The winding wheel 42 can automatically rotate relative to the shell 41 for winding. The shell 41 includes a bottom plate for installation on the launch tube and a protective cover buckled on the bottom plate, and a wire through hole for the wire 44 to pass through is provided on the protective cover; in order to realize the installation of the shell 41 on the launch tube 1, the cover opening of the protective cover is provided with a flange folded outward and in contact with the bottom plate, and the flange and the bottom plate are provided with fastener installation holes for fasteners to pass through to install the assembly body into the launch tube. A flexible rope is wound on the winding wheel 42, specifically, the flexible rope is the wire 44, which is light in weight, and the influence of the gravity of the wire 44 on the test is avoided as much as possible. One end of the pull wire 44 is wound around the winding wheel 42, and the other end is a free end, which can be connected to the mounting ring 14 at the bottom of the load 2 when in use. In order to allow the pull wire 44 to pass through and connect to the load 2, a pull wire perforation is also provided on the top of the housing 41. The pull wire perforation is a small hole structure, which can ensure that the pull wire 44 can pass through. The setting of the housing 41 can also reduce the influence of thick smoke and high temperature on the displacement time detection mechanism when the load 2 is launched. Of course, in other embodiments, the flexible rope can also be set as a steel wire rope or other ropes with low expansion and contraction rates. Alternatively, in other embodiments, a pull wire perforation can also be opened on the side of the housing. Alternatively, in other embodiments, only a protective cover can be provided, and the protective cover can be directly installed at the bottom of the launch tube. Alternatively, in other embodiments, the assembly body can also be set as an open assembly body, which is mainly used for friction test between the load and the launch tube.

[0028] Since one end of the cable 44 needs to be connected to the load 2, the load 2 will drive the cable 44 to move during the movement, and the displacement of the cable 44 is equivalent to the displacement of the load 2. In order to detect the displacement of the cable 44, the displacement time detection mechanism also includes an encoder 43, which is a prior art and can convert the length change in the rotational motion into the change of stroke and time. The encoder 43 is arranged on the winding wheel 42, and the rotation axis of the encoder 43 is colinear with the rotation axis of the winding wheel 42, so that the rotation speed of the winding wheel 42 and the encoder 43 are the same, then the ratio of the displacement measured on the encoder 43 to the displacement of the winding wheel 42 is the ratio of the radius of the two, so the winding speed of the winding wheel 42 can be known through the encoder 43, that is, the displacement and time change relationship of the load 2 is obtained. Of course, in other embodiments, the encoder can also be connected to the winding wheel transmission to maintain a fixed transmission ratio between the two. When calculating the corresponding relationship between displacement and time, the transmission ratio of the two can be considered.

[0029] In order to ensure that the displacement of the pull wire 44 is equal to the displacement of the load 2, the pull wire 44 needs to be arranged vertically so that the extension direction of the pull wire 44 is consistent with the movement direction of the load 2. In this embodiment, a vertically arranged protective tube 45 is also provided on the shell 41. The protective tube 45 is a hollow tube. The tube mouth of the protective tube 45 corresponds to the pull wire perforation on the shell 41, so that after the pull wire 44 passes through the shell 41, it remains vertical under the action of the protective tube 45. At the same time, the protective tube 45 can also be used as a visual reference. Compare the extension direction of the pull wire 44 outside the protective tube 45 to observe whether the pull wire 44 is arranged vertically. Of course, in other embodiments, the protective tube may no longer be provided, and the verticality of the pull wire can be manually visually observed.

[0030] In addition, in order to flatten the cable 44 onto the reel 42 so that the cable 44 fits onto the reel 42, a cable guide 47 is also provided. The cable guide 47 maintains a set gap with the outer periphery of the reel 42 so that the cable 44 is only laid into a single layer and wound on the reel 42 when being wound up, and the length of the cable 44 has a certain relationship with the circumference of the cross section of the reel 42. It is worth noting that the reel 42 is an automatic reel, which is a mature product on the market. Specifically, the winding mechanism of the measuring tape can be referred to so that the cable 44 is always in a straight state. Of course, in order to make the cable 44 straight, the displacement time detection mechanism also includes a brake 46 for braking the reel 42 so that the cable 44 between the reel 42 and the load is in a straight state when the cable 44 is pulled by the load. Specifically, the brake can use a brake that frictionally cooperates with the reel, or it can be set as a disc brake located at the rotating shaft of the reel. Of course, in other embodiments, the rope guide may not be provided, and the wire may be kept thin and not piled up on the reel. Alternatively, in other embodiments, the reel may not be provided with power, and the load needs to be pulled out during the test, so that the load pulls the reel to move, and there is a certain damping between the reel and the housing, so that the wire is in a taut state.

[0031] In the embodiment of the launch tube friction test method of the present invention: The launch tube friction force testing method of the present invention takes the launch tube friction force testing device as an example. Specifically, Figure 3 and Figure 4 As shown, when conducting the test, first, a gantry crane is installed on the periphery of the launch tube 1, and the load 2 is hoisted into the launch tube 1, so that the load 2 is supported on the support ring 13 in the launch tube 1, and the loading of the load 2 is completed. The inspection hole cover is opened, the displacement time detection mechanism is installed in the launch tube 1, and the pull wire 44 in the displacement time detection mechanism is fixed to the installation ring 14 at the bottom of the load 2, completing the preparation work before the test.

[0032] When the displacement-speed detection is required, a gantry crane is used to pull the load 2 upward. During the pulling process, the load 2 needs to be kept rising at a uniform speed as much as possible. A tension sensor 34 is installed on the gantry crane, and a set of tension and time relationship data will be generated accordingly during the pulling process of the load 2. During the uniform rising process of the load 2, the load 2 is in a state of force balance, and the load 2 moves vertically, so the resultant force in the vertical direction is zero. Correspondingly, the friction force and gravity acting in the downward direction and the tension acting in the upward direction are balanced, so the friction force is equal to the tension minus the gravity, so in fact, the relationship between the friction force and time can be obtained. During the rising process of the load 2, the load 2 will drive the bottom pull wire 44 to extend. Since the pull wire 44 is wound on the winding wheel 42, the use of the pull wire 44 will drive the winding wheel 42 to rotate. The winding wheel 42 and the encoder 43 are fixedly connected, and the axes of the two coincide, so one rotation of the winding wheel 42 will drive the encoder 43 to rotate one circle, and the rotation angle of the winding wheel 42 is equal to the rotation angle of the encoder 43. The encoder 43 will obtain the corresponding relationship between displacement (peripheral change of the encoder 43) and time during the rotation process. The winding wheel 42 and the encoder 43 have a fixed radius ratio. The change of the periphery of the winding wheel 42 and time can be obtained by converting the circumference of the two. The wire 44 is wound on the winding wheel 42, which is the corresponding relationship between the displacement and time of the load 2. Finally, the corresponding relationship between the friction force and time of the load 2 and the time in the displacement and time relationship can be obtained to obtain the corresponding relationship between the friction force and displacement, which is convenient for observing the change of the friction force between the load 2 and the launch tube 1 during the process of the load 2 being released. The above method is also the method of using the above-mentioned launch tube friction test device. Of course, in other embodiments, the above-mentioned displacement time detection mechanism may no longer be provided, but a photoelectric displacement sensor or other displacement sensor may be used to output the corresponding relationship between the displacement and time when the load is inserted into or removed from the launch tube.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the contents of the description and drawings of the present invention should also be included in the protection scope of the present invention.

Claims

1. A method for testing the friction force of a launch tube, characterized in that: Place the launch tube vertically, use a lifting mechanism to lift the load and load it into the launch tube or remove it from the launch tube at a uniform speed, use a tension sensor to measure the corresponding relationship between the tension of the lifting mechanism on the load and time during the movement of the load in the launch tube, use a displacement time detection mechanism located in the launch tube to detect the corresponding relationship between the displacement and time when the load is loaded or removed, obtain the corresponding relationship between friction force and time based on the tension and gravity, finally correspond the time in the relationship between friction force and time and displacement and time to obtain the corresponding relationship between friction force and displacement.

2. The method for testing the friction force of a launch tube according to claim 1, characterized in that: The corresponding relationship between the test displacement and time includes connecting a flexible rope to the tail of the load, winding the flexible rope around a winding wheel, keeping the winding wheel and the rotor of the encoder moving synchronously, and synchronously driving the winding wheel and the rotor of the encoder to move when the load is emitted, and outputting the displacement and time relationship of the load through the encoder.

3. A launch tube friction test device, characterized in that: The invention comprises a hoisting mechanism which is arranged outside the launch tube and is used to hoist the load into or out of the launch tube. The hoisting mechanism is provided with a tension sensor which is used to detect the tension provided by the hoisting mechanism in real time and output the corresponding relationship between the tension and time. The invention also comprises a displacement time detection mechanism which is used to detect the corresponding relationship between the displacement time when the load escapes from the launch tube.

4. The launch tube friction force testing device according to claim 3, characterized in that: The displacement time detection structure includes an assembly body for fixing at the bottom of the launching tube, a winding wheel is rotatably mounted on the assembly body, a flexible rope having one end for connecting to a load is wound around the winding wheel, and the displacement time detection mechanism also includes an encoder, and the rotating shaft of the winding wheel and the rotor of the encoder are synchronously connected.

5. The launch tube friction force testing device according to claim 4, characterized in that: The assembly body is a closed shell, and a flexible rope through hole is arranged on the shell for the flexible rope to pass through.

6. The launch tube friction force testing device according to claim 5, characterized in that: The shell body is also provided with a protection tube for the flexible rope to pass through, and the tube opening of the protection tube is communicated with the flexible rope through hole.

7. The launch tube friction force testing device according to any one of claims 4 to 6, characterized in that: The displacement time detection mechanism also includes a brake for braking the winding wheel so that the flexible rope between the winding wheel and the load is in a straight state when the flexible rope is pulled by the load, and the braking force of the brake is set to be less than 1% of the friction between the load and the launching tube when the load escapes from the launching tube.

8. The launch tube friction force testing device according to any one of claims 4 to 6, characterized in that: The displacement time detection mechanism also includes a rope arrangement device which is arranged on the outside of the winding wheel and maintains a preset gap with the winding wheel to squeeze the flexible rope so that the flexible rope can be kept in a single layer winding on the winding wheel.

9. The launch tube friction force testing device according to any one of claims 4 to 6, characterized in that: The rotor of the encoder is fixedly connected to the winding wheel, and the rotation axis of the rotor of the encoder is colinear with the rotation axis of the winding wheel.

10. The launch tube friction force testing device according to claim 5 or 6, characterized in that: The shell comprises a base plate for being mounted on a launching tube and a protective cover buckled on the base plate, and the flexible rope penetration hole is arranged on the protective cover.

11. The launch tube friction force testing device according to claim 10, characterized in that: The cover opening of the protective cover is provided with a flange folded outward and fitted with the base plate, and the flange and the base plate are provided with fastener installation holes for fasteners to pass through so as to install the assembly body into the launching tube.

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