Mounting structure for capacitor on-line monitoring sensor

Abstract

The utility model provides a mounting structure for a capacitor on-line monitoring sensor, which comprises a first orthohexagonal mounting hole positioned in the center of the capacitor on-line monitoring sensor, a hard insulating cushion block and an O-shaped ring, and is characterized in that the lower half part of the hard insulating cushion block is a hollow cylinder; the upper half part is a hollow regular hexagon boss, and a regular hexagon second mounting hole penetrates through the center of the hollow cylinder and the center of the hollow regular hexagon boss. According to the installation structure, the structure of the regular hexagon boss of the capacitor wiring terminal is ingeniously utilized, the hard insulation cushion block and the sensor installation hole which are of the regular hexagon structure are adopted to be matched, the O-shaped ring is adopted to enable the surface of the sensor to make close contact with the Haver wire clamp, and multiple functions are achieved; the current guiding structure, the fastening mode and the fastening degree of an existing capacitor are not affected, stable installation of the sensor is achieved, and the sensor has a very good practical application effect.

Description

Technical Field

[0001] The utility model relates to the field of sensors, and more specifically, to an installation structure for an on-line monitoring sensor of a capacitor. Background Art

[0002] Ultra-high voltage and extra-high voltage AC substations and DC converter stations are equipped with reactive power compensation capacitor banks and filter capacitor banks with relatively large capacities. The capacitor bank is composed of dozens or even hundreds of capacitor units connected in series and parallel. Generally, the operation state of the capacitor is monitored by means of H-bridge unbalance protection. However, limited by measurement accuracy and electromagnetic interference, it is difficult for H-bridge unbalance protection to accurately locate and identify the faults of a small number of components.

[0003] The capacitor unit generally adopts a capacitor structure with internal fuse protection. Inside each capacitor unit, there are dozens or even hundreds of capacitor elements connected in series and parallel, and each capacitor element is connected in series with a fuse. After a component fails and breaks down, under the action of the internal discharge current waveform, the fuse connected in series with the component melts, and the remaining intact components can still operate normally. When a component fault occurs in the capacitor, due to the reduction of the number of components working normally inside, the capacitance value of the capacitor unit changes, and the current flowing through it and the current of the capacitor unit directly connected in parallel with it will both change relatively. Therefore, by comparing the relative changes in the currents of all capacitor units in the capacitor bank at the same moment, the diagnosis of the fault state of the components inside the capacitor unit can be realized.

[0004] Since the capacitor units in different series segments in the capacitor bank have different potentials. The capacitor sensor needs to have functions such as self-power supply or battery power supply, wireless communication, high-precision current measurement, etc. The wiring terminal of the capacitor is the preferred installation position for the sensor, and the shape of the sensor needs to be adapted to the structure at the capacitor wiring terminal, which should be convenient for installation and should not cause safety hazards such as current diversion and insulation. For the specific sensor structure, please refer to the utility model patent with the application number 2020230559576.

[0005] During the actual use process, the following problems may occur when installing the above-mentioned sensor at the capacitor wiring terminal:

[0006] During the actual use process, the following problems may occur when installing the above-mentioned sensor at the capacitor wiring terminal:

[0007] (1) The terminal of a common capacitor has a solid regular hexagonal boss and a stud. The solid regular hexagonal boss is in close contact with the surface of a half-coupling clamp for conducting the capacitor current (usually dozens of amperes). The stud is used to install fasteners, so that there is a certain pre-tightening force between the paired half-coupling clamps and the wires they clamp, and between the half-coupling clamps and the solid regular hexagonal boss, keeping the contact resistance of these contact surfaces at a low level and preventing heat generation. The metal materials of the half-coupling clamps, the solid regular hexagonal boss of the capacitor terminal, and the stud are generally copper plated with tin or copper plated with chromium, and the sensor adopts an aluminum shell structure. If the copper plating fails and comes into contact with metallic aluminum, an electrochemical reaction may occur, corroding the contact surface and increasing the contact resistance. If the corroded part participates in current conduction, heat may be generated. Therefore, the structure of the sensor should avoid current conduction. In addition, the sensor should not be suspended to avoid induced discharge, so the sensor shell should be reliably connected to the capacitor terminal at an equal potential. Since the force for keeping the sensor shell in close contact with the capacitor terminal is in the opposite direction to the pre-tightening force between the half-coupling clamp and the solid regular hexagon and should not be too large.

[0008] (2) The solid regular hexagonal boss of the capacitor terminal also has the function of applying a moment of force: when installing the connecting wire and fastening nut of the capacitor, a thin wrench is used to act on the solid regular hexagonal boss, which can apply a moment of force opposite to the fastening moment to the solid regular hexagonal boss to prevent excessive force on the root of the capacitor bushing and damage. After the sensor is installed, the thin wrench will no longer be able to act on the solid regular hexagonal boss. The sensor installation structure should have a corresponding regular hexagonal structure, which can apply a moment of force opposite to the fastening moment on the sensor and conduct this moment of force to the solid regular hexagonal boss of the capacitor terminal to reduce the force on the root of the capacitor bushing. Summary of the Invention

[0009] In order to solve the technical problems in the prior art that after installing a sensor at the capacitor terminal, the sensor can neither conduct current nor must have a reliable equal-potential connection with the terminal, cannot generate a large force opposite to the pre-tightening force, and the anti-tightening moment cannot be conducted during fastening, the present invention provides an installation structure for an on-line monitoring sensor of a capacitor. The terminal of the capacitor includes a solid cylinder, a solid regular hexagonal boss and a stud on the solid cylinder. The installation structure includes a regular hexagonal first installation hole at the center of the on-line monitoring sensor of the capacitor, a hard insulating spacer and an O-ring. The lower half of the hard insulating spacer is a hollow cylinder, and the upper half is a hollow regular hexagonal boss. A regular hexagonal second installation hole penetrates through the center of the hollow cylinder and the hollow regular hexagonal boss, where:

[0010] The O-ring is sleeved on the solid regular hexagonal boss and contacts the solid cylinder;

[0011] The hollow regular hexagonal boss of the hard insulating spacer passes through the solid regular hexagonal boss, and the bottom of the hollow cylinder presses on the O-ring;

[0012] After the first regular hexagonal mounting hole is aligned with the hollow regular hexagonal boss, they are fitted together.

[0013] Further, the height C3 of the first regular hexagonal mounting hole, the height C2 of the hollow cylinder, and the height C1 of the hollow regular hexagonal boss respectively satisfy the following expressions:

[0014] B1 / 8 ≤ C3 ≤ B1 / 2

[0015] C2 ≤ B1 / 3

[0016] C3 / 2 ≤ C1 < C3

[0017] In the formula, B1 is the height of the solid regular hexagonal boss.

[0018] Further, the side length A2 of the second regular hexagonal mounting hole, the side length A3 of the outside of the hollow regular hexagonal boss, and the side length A4 of the first regular hexagonal mounting hole respectively satisfy the following expressions:

[0019] A2 - A1 ∈ (0mm, 0.5mm]

[0020] A3 - A2 ∈ [2mm, 6mm]

[0021] A4 - A3 ∈ (0mm, 0.5mm]

[0022] In the formula, A1 is the side length of the solid regular hexagonal boss.

[0023] Further, the diameter D4 of the hollow cylinder, the inner diameter D3 of the O-ring, and the cross-sectional diameter D2 respectively satisfy the following expressions:

[0024] D4 < D1

[0025]

[0026] D2 = (k + 1)·(B1 - C3 - C2)

[0027] 0.2 ≤ k ≤ 0.5

[0028] In the formula, D1 is the diameter of the solid cylinder, A1 is the side length of the solid regular hexagonal boss, and k is the compression ratio of the O-ring.

[0029] Further, the material of the hard insulating spacer is engineering plastic.

[0030] Furthermore, the material of the O-ring is one of silicone rubber or fluororubber.

[0031] The installation structure of the capacitor on-line monitoring sensor provided by the technical solution of the present utility model includes a regular hexagon first installation hole located at the center of the capacitor on-line monitoring sensor, a hard insulating cushion block and an O-ring. The lower half of the hard insulating cushion block is a hollow cylinder, and the upper half is a hollow regular hexagon boss. A regular hexagon second installation hole penetrates through the center of the hollow cylinder and the hollow regular hexagon boss, wherein: the O-ring is sleeved on the solid regular hexagon boss and contacts the solid cylinder; the hollow regular hexagon boss of the hard insulating cushion block passes through the solid regular hexagon boss, and the bottom of the hollow cylinder presses on the O-ring; the regular hexagon first installation hole and the hollow regular hexagon boss are aligned and fitted together. The installation structure fully ensures that during the process of installing the fastener of the capacitor terminal, by applying a moment opposite to the nut outside the sensor, other parts of the capacitor bushing can be prevented from being damaged by a large moment. At the same time, the sensor housing is in contact with the Hafer clamp through the elastic force of the O-ring, so that the sensor and the capacitor terminal are in an equipotential state, preventing the sensor from being in a floating potential and causing a discharge phenomenon. The installation structure cleverly utilizes the structure of the hexagonal platform of the capacitor terminal, and cooperates with the hard insulating cushion block and the sensor installation hole with the same hexagonal platform structure, and uses the O-ring to make the surface of the sensor in close contact with the Hafer clamp, realizing multiple functions, neither affecting the current capacitor's current-carrying structure, fastening method and fastening degree, nor realizing the stable installation of the sensor, and having a very good practical application effect. Description of the Drawings

[0032] By referring to the following drawings, the exemplary embodiments of the present utility model can be more fully understood:

[0033] Figure 1 Schematic diagram of the installation structure of the capacitor on-line monitoring sensor according to the preferred embodiment of the present utility model installed on the capacitor terminal;

[0034] Figure 2 Schematic diagram of the structure of the capacitor terminal according to the preferred embodiment of the present utility model;

[0035] Figure 3 Schematic diagram of the structure of the capacitor on-line monitoring sensor according to the preferred embodiment of the present utility model;

[0036] Figure 4 Schematic diagram of the structure of the hard insulating cushion block according to the preferred embodiment of the present utility model;

[0037] Figure 5Schematic diagram of the structure of an O-ring according to a preferred embodiment of the present utility model;

[0038] Figure 6 Cross-sectional view after the installation structure of the capacitor on-line monitoring sensor according to a preferred embodiment of the present utility model is installed on the capacitor terminal. Specific embodiments

[0039] Now, exemplary embodiments of the present utility model will be described with reference to the accompanying drawings. However, the present utility model can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present utility model in detail and completely, and to fully convey the scope of the present utility model to those skilled in the art. The terms in the exemplary embodiments shown in the drawings are not limitations on the present utility model. In the drawings, the same units / cores are denoted by the same reference numerals.

[0040] Unless otherwise specified, the terms used herein (including scientific and technical terms) have the ordinary meaning understood by those skilled in the art. In addition, it can be understood that the terms defined in the commonly used dictionary should be understood to have a meaning consistent with the context of their related fields, and should not be understood as idealized or overly formal meanings.

[0041] Figure 1 Schematic diagram of the installation structure of the capacitor on-line monitoring sensor according to a preferred embodiment of the present invention installed on the capacitor terminal. As Figure 1 shown, the installation structure of the capacitor on-line monitoring sensor described in this preferred embodiment is installed in the order away from the capacitor terminal, which are an O-ring (for the specific structure, see Figure 5 ), a hard insulating spacer, and a sensor. Among them, the terminal of the capacitor includes a solid cylinder, and a solid regular hexagon boss and a stud on the solid cylinder (for the specific structure, see Figure 2 ), there is a regular hexagon first mounting hole on the sensor (for the specific structure, see Figure 3 ), the lower half of the hard insulating spacer is a hollow cylinder, and the upper half is a hollow regular hexagon boss. The regular hexagon second mounting hole penetrates the centers of the hollow cylinder and the hollow regular hexagon boss (for the specific structure, see Figure 4 ). The Hafer clamp, spring washer, nut, fastening nut, and anti-bird cap are conventional means for connecting the connecting wire to the capacitor terminal in the prior art and will not be described herein. The connection relationship between the installation structure of the capacitor on-line monitoring sensor described in the preferred embodiment of the present utility model and the capacitor terminal is:

[0042] The O-ring is sleeved on the solid regular hexagon boss and contacts the solid cylinder;

[0043] The hollow regular hexagon boss of the hard insulating spacer passes through the solid regular hexagon boss, and the bottom of the hollow cylinder presses on the O-ring;

[0044] After the regular hexagon first mounting hole is aligned with the hollow regular hexagon boss, they are fitted together.

[0045] Figure 2 It is a schematic structural diagram of a capacitor terminal according to a preferred embodiment of the present invention. As Figure 2 shown, the schematic structural diagram of the capacitor terminal includes a front view and a top view. From the front view and the top view, it can be seen that the capacitor terminal of the present invention has a structure including a solid cylinder, and a solid regular hexagon boss and a stud located on the solid cylinder from bottom to top. Among them, the diameter of the solid cylinder is D1, the height of the solid regular hexagon boss is B1, and the length of the opposite sides of the solid regular hexagon boss is A1.

[0046] Figure 3 It is a schematic structural diagram of a capacitor on-line monitoring sensor according to a preferred embodiment of the present invention. As Figure 3 shown, the schematic structural diagram of the capacitor on-line monitoring sensor includes a front view and a cross-sectional view. Among them, the cross-sectional view is the result of a front view after being cut open at the place marked as II in the front view. From the front view and the cross-sectional view, it can be seen that the capacitor on-line monitoring sensor of the present invention has a regular hexagon first mounting hole at the center. The length of the opposite sides of the regular hexagon first mounting hole is A4, and the height is C4.

[0047] Figure 4 It is a schematic structural diagram of a hard insulating spacer according to a preferred embodiment of the present invention. As Figure 4 shown, the schematic structural diagram of the hard insulating spacer includes a front view, a top view and a partial enlarged view. Among them, the partial enlarged view is obtained by enlarging the part marked as I in the circle in the front view at a ratio of 1:5. From the top view, the front view and the partial enlarged view, it can be seen that the hard insulating spacer of the present invention includes a hollow regular hexagon boss and a hollow cylinder. Among them, the length of the opposite sides of the outer side of the hollow regular hexagon boss is A3, the length of the opposite sides of the regular hexagon second mounting hole is A2, the height of the hollow regular hexagon boss is C1, and the diameter of the hollow cylinder is D4.

[0048] Figure 5 It is a schematic structural diagram of an O-ring according to a preferred embodiment of the present invention. As Figure 5 shown, the schematic structural diagram of the O-ring is a cross-sectional view after being cut open horizontally. From this figure, it can be seen that the inner diameter of the O-ring is D3, and the cross-sectional diameter is D2.

[0049] Preferably, the height C3 of the first regular hexagon mounting hole, the height C2 of the hollow cylinder, and the height C1 of the hollow regular hexagon boss respectively satisfy the following expressions:

[0050] B1 / 8 ≤ C3 ≤ B1 / 2

[0051] C2 ≤ B1 / 3

[0052] C3 / 2 ≤ C1 < C3

[0053] In the formula, B1 is the height of the solid regular hexagon boss.

[0054] Preferably, the opposite side length A2 of the second regular hexagon mounting hole, the opposite side length A3 outside the hollow regular hexagon boss, and the opposite side length A4 of the first regular hexagon mounting hole respectively satisfy the following expressions:

[0055] A2 - A1 ∈ (0mm, 0.5mm]

[0056] A3 - A2 ∈ [2mm, 6mm]

[0057] A4 - A3 ∈ (0mm, 0.5mm]

[0058] In the formula, A1 is the opposite side length of the solid regular hexagon boss.

[0059] Preferably, the diameter D4 of the hollow cylinder, the inner diameter D3 of the O-ring, and the cross-sectional diameter D2 respectively satisfy the following expressions:

[0060] D4 < D1

[0061]

[0062] D2 = (k + 1)·(B1 - C3 - C2)

[0063] 0.2 ≤ k ≤ 0.5

[0064] In the formula, D1 is the diameter of the solid cylinder, A1 is the opposite side length of the solid regular hexagon boss, and k is the compression ratio of the O-ring.

[0065] Preferably, the material of the hard insulating spacer is engineering plastic.

[0066] Preferably, the material of the O-ring is one of silicone rubber or fluororubber.

[0067] Specifically, in this preferred embodiment, a capacitor terminal is taken as an example. The solid regular hexagon boss of the terminal is copper-tin plated, with dimensions: the opposite side length A1 = 27 mm, the height B1 = 3.5 mm, the diameter D1 of the solid cylinder of the terminal is 48 mm, and the terminal stud is of M16 type.

[0068] According to the set first, second, third, and fourth dimension rules, the material of the sensor housing is made of hard aluminum, with the installation part height C3 = 1 mm and the opposite side length A4 = 32 mm. The hard insulating spacer is made of engineering plastic, with dimensions: the opposite side length A2 of the second regular hexagon mounting hole is 27.5 mm, the opposite side length A3 of the outer side of the hollow regular hexagon boss is 31.5 mm, the height C1 of the hollow regular hexagon boss is 0.8 mm, the height C2 of the hollow cylinder is 1 mm, and the diameter D4 is 45 mm. The O-ring is made of fluororubber, with a cross-sectional diameter D2 = 1.8 mm and an inner diameter D3 = 31.5 mm.

[0069] Figure 6 It is a cross-sectional view after the installation structure of the capacitor on-line monitoring sensor according to the preferred embodiment of the present invention is installed on the capacitor terminal. The cross-sectional view of the regular hexagon first mounting hole of the sensor, the hard insulating spacer, and the O-ring assembled on the terminal according to the above dimensions is as Figure 6 shown. For the cylindrical sealing structure part of the terminal, that is, from the solid cylinder upwards in turn are the O-ring, the hard insulating spacer (simplified as the insulating spacer in the figure), the regular hexagon first mounting hole of the sensor, the paired Hafer wire clips, and the connecting wire between the wire clips. The beneficial effects of the above installation include:

[0070] (1) When calculating the cross-sectional diameter D2 of the O-ring, the selected k value is 0.2. When assembled as Figure 6 shown, the height of the O-ring can be compressed from 1.8 mm to 1.5 mm, which is equivalent to a compression of 20%, thus having a slight elastic force. It is estimated that the elastic force of the O-ring at this compression amount is about 80 N. The height C1 of the hollow regular hexagon boss part of the hard insulating spacer is 0.2 mm smaller than the height C3 of the regular hexagon first mounting hole of the sensor housing installation part, so that the sensor housing contacts the Hafer wire clip instead of the hard insulating spacer contacting the Hafer wire clip. The above two points make the sensor housing and the Hafer wire clip in good contact and maintain an equipotential connection.

[0071] (2) The pre-tightening force between the solid regular hexagon boss of the capacitor terminal and the Hafer wire clip is about 8600 N (under the action of a fastening torque of 25 Nm), and the elastic force of the O-ring is only 1% of the latter, which will not have an adverse effect on the contact resistance of the contact surface of the capacitor terminal.

[0072] (3) Due to the blockage of the hard insulating spacer, the sensor housing does not conduct current.

[0073] (4) The length of the opposite sides of the solid regular hexagonal boss of the terminal block A1 < the length of the opposite sides of the second mounting hole of the regular hexagon of the hard insulating spacer block A2 < the length of the opposite sides of the outer side of the hollow regular hexagonal boss of the hard insulating spacer block A3 < the length of the opposite sides of the first mounting hole of the regular hexagon of the sensor housing A4. Specifically, A1 = 27, A2 = 27.5 mm, A3 = 31.5, A4 = 32, A2 - A1 = 0.5 mm, A4 - A3 = 0.5 mm. The above dimensional relationships ensure that each component can be installed in place without conflict. At the same time, the dimensions of A2 - A1 and A4 - A3 are 0.5 mm. When a torque opposite to the nut is applied outside the sensor, this torque can be well conducted to the hexagonal platform of the capacitor terminal block, which can prevent other parts of the capacitor sleeve from being damaged by a large torque when the nut is tightened.

[0074] The present invention has been described by referring to a few embodiments. However, as is well known to those skilled in the art, as defined by the appended patent claims, other embodiments equivalent to those disclosed above of the present invention equally fall within the scope of the present invention.

[0075] Generally, all terms used in the claims are construed according to their ordinary meanings in the technical field, unless otherwise clearly defined therein. All references to "a / the [device, component, etc.]" are to be construed openly as at least one instance of the device, component, etc., unless otherwise explicitly stated. The steps of any method disclosed herein need not be performed in the exact order disclosed, unless explicitly stated.

[0076] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0077] The present application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate for implementing in the process Figure 1 one process or multiple processes and / or blocksFigure 1 a device for the functions specified in one or more boxes

[0078] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory produce a manufactured article including an instruction device that implements the functions specified in one Figure 1 process or multiple processes and / or boxes Figure 1 a box or multiple boxes

[0079] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are performed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one Figure 1 process or multiple processes and / or boxes Figure 1 a box or multiple boxes

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific embodiments of the present invention. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention shall be covered by the protection scope of the claims of the present invention.

Claims

1. A mounting structure for an online monitoring sensor of a capacitor, wherein the capacitor terminal comprises a solid cylinder, and a solid regular hexagonal boss and a stud on the solid cylinder, characterized in that: The mounting structure comprises a regular hexagonal first mounting hole located at the center of the capacitor online monitoring sensor, a hard insulating pad and an O-ring, the lower half of the hard insulating pad is a hollow cylinder, the upper half is a hollow regular hexagonal boss, and the regular hexagonal second mounting hole passes through the center of the hollow cylinder and the hollow regular hexagonal boss, wherein: The O-ring is sleeved on the solid regular hexagonal boss and contacts the solid cylinder; The hollow regular hexagonal boss of the hard insulating spacer passes through the solid regular hexagonal boss, and the bottom of the hollow cylinder is pressed on the O-ring; The regular hexagonal first mounting hole is aligned with the hollow regular hexagonal boss and embedded together.

2. The mounting structure according to claim 1, characterized in that: The height C3 of the regular hexagonal first mounting hole, the height C2 of the hollow cylinder and the height C1 of the hollow regular hexagonal boss respectively satisfy the following expressions: B1 / 8≤C3≤B1 / 2 C2≤B1 / 3 C3 / 2≤C1<C3 Wherein, B1 is the height of the solid regular hexagonal boss.

3. The mounting structure according to claim 1, characterized in that: The length of opposite sides A2 of the regular hexagonal second mounting hole, the length of opposite sides A3 of the outer side of the hollow regular hexagonal boss, and the length of opposite sides A4 of the regular hexagonal first mounting hole respectively satisfy the following expressions: A2-A1∈(0mm,0.5mm] A3-A2∈[2mm,6mm] A4-A3∈(0mm,0.5mm] Wherein, A1 is the length of the opposite side of the solid regular hexagonal boss.

4. The mounting structure according to claim 1, characterized in that: The diameter D4 of the hollow cylinder, the inner diameter D3 and the cross-sectional diameter D2 of the O-ring respectively satisfy the following expressions: D4<D1 D2=(k+1)·(B1-C3-C2) 0.2≤k≤0.5 In the formula, D1 is the diameter of the solid cylinder, A1 is the length of the opposite side of the solid regular hexagonal boss, and k is the compression ratio of the O-ring.

5. The mounting structure according to claim 1, characterized in that: The material of the hard insulating spacer is engineering plastic.

6. The mounting structure according to claim 1, characterized in that: The material of the O-ring is silicone rubber or fluororubber.

Images