A Measuring Mechanism and Method for Radial Displacement of a Composite Material Cylindrical Pressure Resistant Shell

Abstract

A radial displacement measuring mechanism and method for a composite cylindrical pressure-resistant shell of the present invention belong to the field of displacement measurement; it includes a measurement module and a fixing module. A plurality of measurement modules are evenly distributed circumferentially and fixed to the shell to be measured through the fixing module; the probe of the measurement module contacts the inner wall of the shell, and the radial displacement of each position when the shell is pressurized is obtained through the compression amount and restoration amount of the probes of the plurality of measurement modules. The present invention can solve the problem of measuring the radial displacement of a cylindrical shell when it is under external pressure through the assembly of simple mechanical components. The entire mechanism is directly fixed on the metal skirt of the shell. Since the strength and stiffness at the metal skirt of the shell are relatively large, using this place as the installation reference for the entire mechanism can ensure the accuracy of the measurement data.

Description

Technical Field

[0001] The present invention belongs to the field of displacement measurement, and particularly relates to a radial displacement measurement mechanism and method for a composite cylindrical pressure-resistant shell. Background Art

[0002] The pressure-resistant shell of an underwater vehicle is an important part to ensure the normal operation of the entire vehicle. Therefore, before the vehicle operates, a pressure test needs to be carried out on its pressure-resistant shell, the displacement data of the pressure-resistant shell under the action of hydrostatic pressure is collected, and it is analyzed to determine whether the shell can meet the required strength and stability requirements.

[0003] At present, the deformation data of the shell is mainly obtained by pasting strain gauges on the shell wall. This type of measurement method can only obtain the strain values in the in-plane direction of the cylindrical shell, but cannot obtain the radial displacement values of the cylindrical shell, making the understanding of the structural mechanical response of the cylindrical shell not comprehensive. In addition, there are many instruments and equipment that need to be installed inside the pressure-resistant shell. Usually, these devices are close to the inner wall of the shell. During actual use, it is necessary to measure the radial displacement of the shell to ensure that the pressure-resistant shell of the vehicle does not interfere with the internal instruments after deformation and does not affect the normal operation of the instruments and equipment. However, there is currently no mechanism that can be used to measure the radial displacement of a cylindrical shell. Summary of the Invention

[0004] Technical problems to be solved:

[0005] In order to avoid the deficiencies of the prior art, the present invention provides a radial displacement measurement mechanism and method for a composite cylindrical pressure-resistant shell, which can effectively solve the problem that it is difficult to measure the radial displacement of a cylindrical pressure-resistant shell after being subjected to external pressure.

[0006] The technical solution of the present invention is: a radial displacement measurement mechanism for a composite cylindrical pressure-resistant shell, including a measurement module and a fixing module. A plurality of measurement modules are circumferentially distributed evenly and fixed inside the shell to be measured through the fixing module;

[0007] The probe of the measurement module contacts the inner wall of the shell, and the radial displacements of each position of the shell when it is pressurized are obtained through the compression and restoration amounts of the probes of the plurality of measurement modules.

[0008] A further technical solution of the present invention is: the measurement module is a displacement sensor, the axial direction of the displacement sensor is set along the radius direction of the shell, and its contact head contacts the inner wall of the shell; through the change of the force exerted by the shell on the probe, the radial displacement of the probe changes, and then the change of the radial displacement of the shell is measured.

[0009] A further technical solution of the present invention is that: the fixing module includes a displacement sensor bracket and a fixing frame, the displacement sensor bracket is of an annular structure and is coaxially fixed inside the housing through the fixing frame;

[0010] A plurality of the displacement sensors are circumferentially fixed on the displacement sensor bracket, and the radial displacement information of the circumferential surface of the housing can be obtained.

[0011] A further technical solution of the present invention is that: the fixing frame includes a connecting rod and a connecting arc;

[0012] The connecting arc is an arc-shaped strip plate, the two ends of which are fixed on the inner circumferential surface of the metal skirt at the outer edge of the housing, and the middle part is fixed to one end of the connecting rod; a plurality of connecting arcs are evenly distributed circumferentially;

[0013] A plurality of the connecting rods are evenly distributed circumferentially and are arranged in one-to-one correspondence with the connecting arcs, and the other ends of them are all fixedly connected to the displacement sensor bracket, realizing a firm connection between the displacement sensor bracket and the housing.

[0014] A further technical solution of the present invention is that: the number of both the connecting arc and the connecting rod is 3.

[0015] A further technical solution of the present invention is that: the displacement sensor bracket is of a hexagonal structure, and 6 displacement sensors are respectively installed on the center lines of the six sides; the other ends of the connecting rods are fixedly connected to the top angles of the displacement sensor bracket.

[0016] A further technical solution of the present invention is that: the maximum outer diameter of the displacement sensor bracket is smaller than the inner diameter of the housing.

[0017] A further technical solution of the present invention is that: the connecting rod is parallel to the central axis of the housing, and a plurality of mounting ports are evenly distributed along the length direction for axially mounting a plurality of displacement sensor brackets inside the housing, and the displacement sensor mounting planes of each displacement sensor bracket are perpendicular to the central axis of the housing; realizing the measurement of the circumferential radial displacement of multiple cross-sections inside the housing.

[0018] A further technical solution of the present invention is that: each component in the measuring mechanism is fixedly connected by screws and nuts.

[0019] An installation method for a radial displacement measuring mechanism of a composite cylindrical pressure-resistant housing is as follows:

[0020] Step 1: Fix the connection between the displacement sensor bracket and the mounting port of the connecting rod;

[0021] Step 2: Install the displacement sensor on the displacement sensor bracket, and then place it inside the housing;

[0022] Step 3: Fix the connection between the middle hole of the connecting arc and the fixed port of the connecting rod;

[0023] Step 4: Fix the mounting holes at both ends of the connecting arc to the mounting holes on the metal skirt of the housing.

[0024] Step 5: Fine-tune the displacement sensor so that its probe is in full contact with the housing and zero it; complete the installation of the entire measuring mechanism.

[0025] Beneficial effects

[0026] The beneficial effects of the present invention are as follows:

[0027] (1) The present invention can solve the problem of radial displacement of a cylindrical shell under external pressure through simple mechanical component assembly.

[0028] (2) Fixing the entire mechanism directly on the metal skirt of the housing reduces the complexity of the mechanism. At the same time, since the strength and stiffness of the metal skirt of the housing are relatively large, using this as the installation reference for the entire mechanism can ensure the accuracy of the measurement data.

[0029] (3) According to actual needs, by changing the number of mounting ports on the connecting rod and the number of sensors installed on the displacement sensor bracket, radial displacement data at any number of measurement points can be obtained.

[0030] (4) Changes in the shape of the housing will cause compression or restoration of the probe of the displacement sensor. The continuous change of the radial displacement of the housing under external pressure can be directly obtained through the compression and restoration amounts of the probe. Figure 7 Schematic diagram of the distribution of displacement sensors and the deformation of the housing; Figure 8 is the radial displacement obtained by using this measuring mechanism and method when the housing is under external pressure. Description of the drawings

[0031] Figure 1 is a three-dimensional cross-sectional view of this measuring mechanism;

[0032] Figure 2 is a schematic diagram of the installation of the displacement sensor;

[0033] Figure 3 is a schematic diagram of the displacement sensor;

[0034] Figure 4 is a schematic diagram of the displacement sensor bracket;

[0035] Figure 5 is a schematic diagram of the connecting rod;

[0036] Figure 6 is a schematic diagram of the connecting arc;

[0037] Figure 7It is the distribution diagram of displacement sensor measuring points and the shell deformation diagram (the solid line is before deformation, and the dashed line is after deformation);

[0038] Figure 8 It is the radial displacement measured by the displacement sensor.

[0039] Explanation of reference numerals: 1 - metal skirt, 2 - composite material shell, 3 - connecting arc, 4 - connecting rod, 5 - displacement sensor bracket, 6 - displacement sensor, 7 - nut, 8 - screw, 9 - mounting hole, 10 - probe of displacement sensor, 11 - mounting port, 12 - fixed port. Specific implementation mode

[0040] The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0041] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

[0042] The present invention provides a radial displacement measuring mechanism for a composite material cylindrical pressure-resistant shell, and this mechanism is applied to the composite material shell 2 with a metal skirt 1; the cross-sectional view of the mechanism is as Figure 1 shown, including a connecting arc 3, a connecting rod 4, a displacement sensor bracket 5, a displacement sensor 6, a nut 7, and a screw 8, and the main components are as Figures 3 - 6 shown.

[0043] Both ends of the composite material shell 2 are bonded to the metal skirt 1 through an adhesive to ensure the sealing of the bonding surface. The displacement sensor 6 is connected to the displacement sensor bracket 5 through screws 8 and nuts 7 to ensure that the displacement sensor will not move during use. The displacement sensor bracket 5 is connected to one end of the connecting rod 4 through screws 8 and nuts 7 to ensure that the displacement sensor 6 can measure the displacement at multiple spatial positions on the inner wall surface of the shell. The other end of the connecting rod 4 is connected to the connecting arc 3 through screws 8 and nuts 7, and then the connecting arc 3 is fixed on the metal skirt 1. The metal skirt has relatively high strength and stiffness to ensure that the entire measuring mechanism can be in a fixed state during use.

[0044] The connecting arc 3, the connecting rod 4, the displacement sensor bracket 5, the nut 8, and the screw 7 are all processed from high-strength metal materials.

[0045] The maximum radial dimension of the displacement sensor bracket 5 should be smaller than the minimum radius of the cylindrical shell to ensure that the displacement sensor bracket can be placed inside the pressure-resistant shell.

[0046] A number of through holes are opened on the displacement sensor bracket. These through holes have the same positions and sizes as the displacement sensor mounting holes and are used to install the displacement sensor. Specifically, as shown in Figure 2 , 3 , the mounting hole 9 shown in 4.

[0047] The lengths of the connecting rods 4 must be equal. After being connected to the displacement sensor bracket, the mounting plane of the displacement sensor bracket must be perpendicular to the axis of the shell to ensure that the displacement sensor measures the radial displacement value on the same cross-section.

[0048] The connecting arc 3 and the connecting rod 4 are evenly distributed inside the shell. While ensuring that the entire measuring mechanism has good stiffness, it can also ensure that the probe of each displacement sensor is in full contact with the inner wall surface of the shell, thereby improving the accuracy of the measurement result.

[0049] The perpendicular distance from the middle through hole to the connecting line of the two end through holes on the connecting arc 3 must be greater than the size of the fixed port 12 on the connecting rod 4 to ensure that there is no interference with the inner wall surface of the shell when installing the connecting rod 4.

[0050] After the displacement sensor is installed, its probe must be in full contact with the inner wall surface of the shell and have a certain amount of compression to ensure that during the measurement process, regardless of how the shape of the shell changes, the probe of the displacement sensor always contacts the inner wall surface of the shell.

[0051] In this embodiment, the installation method of a radial displacement measuring mechanism for a composite material cylindrical pressure-resistant shell is as follows:

[0052] Step 1: Fix and connect the displacement sensor bracket 5 and the mounting port 11 of the connecting rod 4 through the screw 8 and the nut 7.

[0053] Step 2: Install the displacement sensor 6 on the displacement sensor bracket 5 through the screw 8 and the nut 7, and then place it inside the composite material shell 2.

[0054] Step 3: Fix the middle hole on the connecting arc 3 and the fixed port 12 of the connecting rod 4 through the screw 8 and the nut 7.

[0055] Step 4: Fix the mounting holes 9 at both ends of the connecting arc 3 and the mounting holes on the metal skirt 1 through the screw 8 and the nut 7.

[0056] Step Five: Fine-tune the displacement sensor 6 so that its probe is in full contact with the housing 2 and zero it. Complete the installation of the entire measuring mechanism.

[0057] A radial displacement measuring mechanism and method for a cylindrical pressure-resistant housing provided by the present invention are particularly applicable to the measurement of the radial displacement of a cylindrical pressure-resistant housing of an underwater vehicle after being subjected to external pressure.

[0058] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention without departing from the principles and purposes of the present invention.

Claims

1. A radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell, characterized in that: It includes a measurement module and a fixing module. Multiple measurement modules are evenly distributed circumferentially and fixed to the shell to be measured through the fixing module; The probe of the measurement module contacts the inner wall of the shell, and the radial displacement of each position of the shell when it is pressurized is obtained through the compression amount and recovery amount of the probes of multiple measurement modules; The measurement module is a displacement sensor. The axial direction of the displacement sensor is set along the radius direction of the shell, and its contact head contacts the inner wall of the shell; through the change of the force exerted by the shell on the probe, the radial displacement of the probe changes, and then the radial displacement change of the shell is measured; The fixing module includes a displacement sensor bracket and a fixing frame. The displacement sensor bracket is of an annular structure and is coaxially fixed to the shell through the fixing frame; multiple displacement sensors are fixed to the displacement sensor bracket circumferentially, and the radial displacement information of the circumferential surface of the shell can be obtained; The fixing frame includes a connecting rod and a connecting arc; the connecting arc is an arc-shaped strip plate, the two ends of which are fixed to the inner circumferential surface of the metal skirt on the outer edge of the shell, and the middle part is fixed to one end of the connecting rod; multiple connecting arcs are evenly distributed circumferentially; multiple connecting rods are evenly distributed circumferentially and are arranged in one-to-one correspondence with the connecting arcs, and the other ends of them are all fixedly connected to the displacement sensor bracket, realizing a stable connection between the displacement sensor bracket and the shell; The connecting rod is parallel to the central axis of the shell, and multiple installation ports are evenly distributed along the length direction for axially installing multiple displacement sensor brackets in the shell. The displacement sensor installation planes of each displacement sensor bracket are all perpendicular to the central axis of the shell; realizing the measurement of the circumferential radial displacement of multiple cross-sections in the shell.

2. The radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell according to claim 1, characterized in that: The displacement sensor bracket is of a hexagonal structure, and 6 displacement sensors are respectively installed on the center lines of the six sides; the other end of the connecting rod is fixedly connected to the vertex angle of the displacement sensor bracket.

3. The radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell according to claim 1, characterized in that: The number of both the connecting arc and the connecting rod is 3.

4. The radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell according to claim 1, characterized in that: The maximum outer diameter of the displacement sensor bracket is smaller than the inner diameter of the shell.

5. The radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell according to claim 1, characterized in that: All components in the measuring mechanism are fixedly connected by screws and nuts.

6. An installation method for the radial displacement measuring mechanism for a composite cylindrical pressure-resistant shell according to any one of claims 1-5, characterized in that The specific steps are as follows: Step 1: Fix the connection between the displacement sensor bracket and the installation port of the connecting rod; Step 2: Install the displacement sensor on the displacement sensor bracket, and then put it into the interior of the shell; Step 3: Fix the connection between the middle hole of the connecting arc and the fixed port of the connecting rod; Step 4: Fix the connection between the installation holes at both ends of the connecting arc and the installation holes on the metal skirt of the shell; Step Five: Fine-tune the displacement sensor so that its probe is in full contact with the housing and zero it; complete the installation of the entire measuring mechanism.

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