Sealing structure and method of assembling a sealing structure

Abstract

The present application provides a sealing structure capable of exerting stable sealing performance for a long period of time and a method for assembling the sealing structure. A mounting member (300) is provided with an annular fitting groove (310) for fitting a sealing gasket (100) made of resin, and an annular protrusion (311) is provided at the bottom of the fitting groove (310), the annular protrusion (311) having a tapered surface (311a) that expands in diameter from a pressurizing side (H) toward a counter-pressurizing side (L) and a tapered surface (311b) that contracts in diameter from the pressurizing side (H) toward the counter-pressurizing side (L), and the leading end of the annular protrusion (311) is disposed in a manner deviated toward the pressurizing side (H) from the center of the groove width direction of the fitting groove (310).

Description

Technical Field

[0001] This invention relates to a sealing structure including a resin gasket and a method for assembling the sealing structure. Background Technology

[0002] At the location where the injector is mounted relative to the cylinder head of the engine, a resin gasket is provided to prevent leakage of high-pressure combustion gases from the annular gap formed between the mounting hole in the cylinder head and the injector. For example, a gasket made of PTFE, which has excellent heat resistance and pressure resistance, is suitable. However, with such a gasket, creep occurs due to long-term use, and thermal shrinkage intensifies over time, gradually reducing the sealing performance. Therefore, it is known that a technique is used where a tapering surface that expands from the high-pressure side to the low-pressure side is provided on the bottom surface of the gasket mounting groove provided in the injector, thereby narrowing the gap from the high-pressure side to the low-pressure side (see Patent Document 1). By adopting such a structure, even with the intensified thermal shrinkage of the gasket over time, a self-sealing function is performed under the pressure generated by the combustion gases, thereby maintaining the sealing performance.

[0003] However, even with the structure described above, gaps can still form between the outer circumferential surface of the gasket and the inner circumferential surface of the mounting hole in gaskets where creep is exacerbated, especially at low temperatures. These gaps gradually widen over time, inevitably leading to a gradual decrease in sealing performance. Therefore, gaskets that provide a more stable and long-term seal are desirable.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 3830896 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] The purpose of this invention is to provide a sealing structure and a method for assembling the sealing structure that can maintain stable sealing performance over a long period of time.

[0009] Solutions for solving technical problems

[0010] To solve the above-mentioned technical problems, the present invention employs the following means.

[0011] That is, the sealing structure of the present invention includes:

[0012] The component to be installed has mounting holes;

[0013] Mounting components are installed in the mounting holes; and

[0014] A cylindrical resin gasket, through an annular gap disposed between the mounting hole and the mounting component, seals the pressure side (high pressure due to the pressure of the fluid being sealed) and the counter-pressure side (opposite to the pressure side).

[0015] The sealing structure is characterized in that...

[0016] The mounting component is provided with an annular mounting groove for assembling the resin sealing gasket.

[0017] An annular protrusion is provided at the bottom of the assembly groove. The annular protrusion has a tapered surface that expands from the pressurized side toward the anti-pressurized side and a tapered surface that narrows from the pressurized side toward the anti-pressurized side. The front end of the annular protrusion is arranged such that it is offset toward the pressurized side from the center of the groove width direction in the assembly groove.

[0018] According to the present invention, when pressure from the pressurized side acts on the resin gasket, it is resisted by the tapering surface that expands from the pressurized side towards the anti-pressurized side, causing the resin gasket to press against the outer peripheral surface, thereby achieving a self-sealing function. Furthermore, the front end of the annular protrusion is positioned such that it is offset towards the pressurized side from the center in the groove width direction of the mounting groove, thus suppressing the formation of a gap between the outer peripheral surface of the gasket, particularly near the pressurized side, and the inner peripheral surface of the mounting hole. Therefore, even in gaskets where creep is exacerbated, and under low-temperature conditions, the gap formed between the outer peripheral surface of the gasket and the inner peripheral surface of the mounting hole can be narrowed near the pressurized side. Thus, by narrowing the gap formed on the outer peripheral surface of the gasket near the pressurized side and the inner peripheral surface of the mounting hole, leakage of the fluid being sealed can be suppressed compared to the case where the gap is wide.

[0019] The resin sealing gasket can be assembled in the assembly groove at a position biased towards the pressurized side, and when no pressure is applied from the pressurized side, a gap is provided between the side wall of the counter-pressurized side in the assembly groove and the resin sealing gasket.

[0020] Therefore, it is possible to suppress the dispersion of resistance to the resin gasket caused by pressure from the pressurized side, and to increase the resistance encountered by the tapered surface of the resin gasket as it expands from the pressurized side toward the counter-pressurized side, thereby fully realizing its self-sealing function.

[0021] The sidewall of the pressurized side in the assembly groove can be formed by a surface perpendicular to the central axis of the resin gasket.

[0022] This improves the ease of assembling resin gaskets into the assembly groove.

[0023] Furthermore, the assembly method of the sealing structure of the present invention is characterized by having:

[0024] The process of assembling the resin seal into the mounting groove after the resin seal is inserted into the mounting component from the pressure side, and then sliding the resin seal toward the mounting groove until the end face of the resin seal on the pressure side passes through the side wall of the pressure side in the mounting groove; and

[0025] The process of installing the mounting component, which is fitted with the resin sealing gasket, into the mounting hole of the component to be mounted.

[0026] Thus, after the resin gasket is embedded relative to the mounting component, it slides towards the mounting groove, thereby assembling the resin gasket into the mounting groove. Furthermore, during the sliding of the resin gasket, its front end abuts against the tapered surface of the annular protrusion provided in the mounting groove. This tapered surface is configured to expand in diameter from the pressurized side to the anti-pressurized side, allowing the resin gasket to slide smoothly from the pressurized side to the anti-pressurized side. Additionally, when the sidewall of the pressurized side in the mounting groove is composed of a surface perpendicular to the central axis of the resin gasket, the resin gasket is assembled into the mounting groove without resistance from the sidewall when the end face of the pressurized side of the resin gasket passes through the sidewall of the pressurized side in the mounting groove. Therefore, the resin gasket can be easily positioned at a predetermined position within the mounting groove.

[0027] It should be noted that the above structures can be used in combination as much as possible.

[0028] Invention Effects

[0029] As explained above, the present invention can maintain stable sealing performance over a long period of time. Attached Figure Description

[0030] Figure 1 This is a schematic structural diagram of a resin-made sealing gasket according to an embodiment of the present invention.

[0031] Figure 2 This is a schematic structural diagram of the installed component and the mounting parts according to an embodiment of the present invention.

[0032] Figure 3 This is a schematic cross-sectional view of the sealing structure according to an embodiment of the present invention.

[0033] Figure 4 This is an illustration of the assembly method of resin gaskets to mounting components.

[0034] Figure 5 It is a schematic diagram of the evaluation test apparatus.

[0035] Figure 6 This is a graph showing the evaluation test results of the sealing structure according to an embodiment of the present invention.

[0036] Figure 7 This is a graph showing the evaluation test results of the sealing structure according to an embodiment of the present invention.

[0037] Figure 8 This is a graph showing the evaluation test results of the sealing structure according to an embodiment of the present invention.

[0038] Figure 9 This is a graph showing the evaluation test results of the sealing structure according to an embodiment of the present invention. Detailed Implementation

[0039] Hereinafter, with reference to the accompanying drawings, exemplary embodiments are described to illustrate how to implement the invention. However, the dimensions, materials, shapes, and relative arrangements of the structural components described in these embodiments are not intended to limit the scope of the invention, unless otherwise specifically stated.

[0040] In the following description, the case where the mounted component is the cylinder head of an engine and the mounting component is an injector mounted in a mounting hole formed in the cylinder head is used as an example. In particular, the sealing structure of this embodiment can be suitably applied to the fuel injection device of a direct injection gasoline engine. However, the present invention is not limited to the cylinder head; in particular, it can be applied to a sealing structure that closes the annular gap between the mounting hole formed in the component (mounted component) exposed to high-pressure fluid and the various mounting components mounted in that mounting hole.

[0041] (Example)

[0042] Reference Figures 1-9 The sealing structure and assembly method of the sealing structure according to embodiments of the present invention will be described. Figure 1 This is a schematic structural diagram of a resin sealing gasket according to an embodiment of the present invention, showing a partial cross-sectional view of a portion of the resin sealing gasket (the upper half in the figure). Figure 2 This is a schematic structural diagram of the mounted component and mounting parts according to an embodiment of the present invention. In the sealing structure, a schematic cross-sectional view is used to show the schematic structure with the resin sealing gasket omitted. Figure 3 This is a schematic cross-sectional view of the sealing structure according to an embodiment of the present invention. Figure 4 An illustration of the assembly method of a resin gasket to a mounting component is provided, using a schematic cross-sectional view to show the configuration of the resin gasket when assembled relative to the mounting component. Figure 5 It is a schematic diagram of the evaluation test apparatus. Figures 6-9 This is a graph showing the evaluation test results of the sealing structure according to an embodiment of the present invention.

[0043] <Resin-made sealing gaskets>

[0044] In particular, refer to Figure 1 The resin-made sealing gasket (hereinafter referred to as sealing gasket 100) of this embodiment will be described. The sealing gasket 100 of this embodiment is composed of a cylindrical component. The cross-section of the sealing gasket 100 cut along a plane including its central axis is rectangular. Furthermore, polytetrafluoroethylene (PTFE), which has excellent heat resistance and pressure resistance, can be suitable as the material for the sealing gasket 100. When manufacturing the sealing gasket 100 using PTF, low-temperature shrinkage can be suppressed by making the filler material content 20 vol% or more. It should be noted that by making the particle size of the added filler material 20 μm or less, leakage of the fluid to be sealed from the gap in the sealing surface (in this embodiment, this corresponds to combustion gases produced during combustion in an engine cylinder) can be suppressed.

[0045] <Installed components and mounting parts>

[0046] In particular, refer to Figure 2 The mounted component 200 and mounting member 300 of this embodiment will be described below. The mounted component 200 (in this embodiment, a cylinder block cover) has a cylindrical mounting hole 210. Furthermore, the mounting member 300 (in this embodiment, an injector) mounted in the mounting hole 210 has an annular mounting groove 310 for assembling the sealing gasket 100. Figure 2 ( Figure 3 and Figure 4 Similarly, in the diagram, the right side is the side that becomes high-pressure due to the fluid (combustion gas) being sealed during the use of the device (in this embodiment, an engine) (hereinafter referred to as the pressurized side (H)), and the left side is its opposite side (hereinafter referred to as the anti-pressurized side (L)). It should be noted that the sealing gasket 100 is disposed in the annular gap between the mounting hole 210 and the mounting component 300, thereby serving to seal the pressurized side (H) and its opposite anti-pressurized side (L).

[0047] An annular protrusion 311 is provided at the bottom of the mounting groove 310 of the mounting component 300. This annular protrusion 311 is composed of a tapering surface (a conical surface that appears straight in cross-section) 311a that expands from the pressure side (H) towards the counter-pressure side (L) and a tapering surface 311b that narrows from the pressure side (H) towards the counter-pressure side (L). The tapering angle of the tapering surface 311a on the pressure side (H) is configured to be larger than the tapering angle of the tapering surface 311b on the counter-pressure side (L), and the length of the tapering surface 311a on the pressure side (H) in the axial direction (direction of the central axis of the mounting component 300) is configured to be shorter than the length of the tapering surface 311b on the counter-pressure side (L). It should be noted that the tapering angle refers to the angle between the two generatrices of a cone on a cross-section. Furthermore, the front end of the annular protrusion 311 (the boundary portion between the tapered surfaces 311a and 311b) is configured to be more biased toward the pressure side (H) than the center of the groove width direction in the assembly groove 310. It should be noted that, in the example shown, no chamfer is provided for the boundary portion between the tapered surfaces 311a and 311b, but chamfers such as R-surfaces can also be provided.

[0048] Furthermore, the side wall surface 312 of the pressurized side (H) in the assembly groove 310 is formed by a surface perpendicular to the central axis of the sealing gasket 100. Similarly, the side wall surface 313 of the counter-pressurized side (L) in the assembly groove 310 is also formed by a surface perpendicular to the central axis of the sealing gasket 100. However, the side wall surface 313 of the counter-pressurized side (L) may also be formed by an inclined surface such as a tapered surface. It should be noted that in this embodiment, the tapered surface 311a of the annular protrusion 311 is connected to the side wall surface 312 of the pressurized side (H) by a curved surface, and the tapered surface 311b of the annular protrusion 311 is also connected to the side wall surface 313 of the counter-pressurized side (L) by a curved surface.

[0049] <Dimensional relationships of each component>

[0050] The dimensional relationships of the components constituting the sealing structure are explained. The width along the central axis of the sealing gasket 100 is defined as W10, the inner diameter of the sealing gasket 100 as D11, and the outer diameter of the sealing gasket 100 as D12 (refer to...). Figure 1 Additionally, the inner diameter of the mounting hole 210 of the component to be mounted is set to D20 (refer to...). Figure 2Furthermore, the width of the mounting groove 310 (width in the direction of the central axis) is set to W31, and the distance from the side wall 312 of the pressurized side (H) to the front end of the annular protrusion 311 (the boundary portion between the tapered surfaces 311a and 311b) is set to W32. Also, the outer diameter near the outer side of the mounting groove 310 in the mounting component 300 is set to D31, the outer diameter of the smallest diameter portion at the bottom of the mounting groove 310 is set to D32, and the outer diameter of the front end of the annular protrusion 311 is set to D33 (see reference). Figure 2 ).

[0051] Therefore, satisfaction

[0052] D11<D32<D33<D12<D31<D20

[0053] W32 < W10 < W31. It should be noted that in this embodiment, a structure satisfying the relationship D12 < D31 < D20 is adopted. However, since the relationship D11 < D32 < D33 is satisfied, the sealing gasket 100 is enlarged in diameter when it is assembled in the mounting groove 310, so that the outer peripheral surface of the sealing gasket 100 is in close contact with the inner peripheral surface of the mounting hole 210.

[0054] <Sealing Structure>

[0055] In particular, refer to Figure 3 The sealing structure of this embodiment will be described below. When the sealing gasket 100 is assembled in the mounting groove 310, it closes the annular gap between the mounting hole 210 and the mounting member 300. By satisfying the dimensional relationship described above, the sealing gasket 100 is pressed radially outward by the annular protrusion 311 provided in the mounting groove 310, and radially inward by the inner circumferential surface of the mounting hole 210, thereby becoming radially compressed. Furthermore, a gap S is provided between the side wall surface 313 on the counter-pressurization side (L) of the mounting groove 310 and the sealing gasket 100. In this embodiment, the sealing gasket 100 is assembled at a position biased towards the pressurization side (H). That is, the sealing gasket 100 is assembled in the mounting groove 310 such that the center position of the width of the sealing gasket 100 in the central axis direction is located further towards the pressurization side (H) than the center position of the groove width of the mounting groove 310. It should be noted that, under the conditions of use, the dimensions of each part are set in a way that maintains the above-mentioned gap S even when pressure is applied from the pressurized side (H).

[0056] <Assembly method of sealing structure>

[0057] In particular, refer to Figure 4The assembly method of the sealing structure in this embodiment will be described below. The assembly method of this embodiment includes: a step of assembling the sealing gasket 100 into the assembly groove 310 of the mounting component 300; and a step of installing the mounting component 300 with the sealing gasket 100 assembled into the mounting hole 210 of the mounted component 200. Hereinafter, the former step will be described in more detail.

[0058] First, from the state where the mounting component 300 and the sealing gasket 100 are positioned coaxially (see reference). Figure 4 Starting from (a)), the sealing gasket 100 is embedded into the mounting component 300 from the pressurized side (H) (see reference). Figure 4 (b)). Then, the sealing gasket 100 slides toward the mounting groove 310. During this process, the front end of the sealing gasket 100 slides relative to the tapered surface 311a in the annular protrusion 311 (see reference). Figure 4 (c)). Furthermore, when the end face of the pressure side (H) in the sealing gasket 100 passes through the side wall 312 of the pressure side (H) in the assembly groove 310, the sealing gasket 100 shrinks in diameter due to its own elastic restoring force, thus becoming assembled in the assembly groove 310 (see reference). Figure 4 (d) It should be noted that when assembling the sealing gasket 100, the side of the pressure side (H) in the sealing gasket 100 and the side wall surface 312 in the assembly groove 310 can be either in close contact or have a gap.

[0059] <Advantages of the sealing structure and its assembly method in this embodiment>

[0060] According to this embodiment, when pressure from the pressurized side (H) acts on the sealing gasket 100, it is resisted by the tapered surface 311a, causing the sealing gasket 100 to press against the outer peripheral surface, thereby performing a self-sealing function. In other words, the sealing gasket 100 is compressed between the tapered surface 311a and the inner peripheral surface of the mounting hole 210, near the area opposite to the tapered surface 311a, thus performing a self-sealing function. Furthermore, movement of the sealing gasket 100 towards the reverse pressurized side (L) is also suppressed.

[0061] Furthermore, in this embodiment, a gap S is provided between the side wall surface 313 of the counter-pressurization side (L) in the assembly groove 310 and the sealing gasket 100. Therefore, the dispersion of resistance acting on the sealing gasket 100 due to pressure from the pressurization side (H) can be suppressed, the resistance experienced by the sealing gasket 100 from the tapered surface 311a can be increased, and the self-sealing function can be fully utilized. This will be explained in more detail. When the sealing gasket 100 is configured in contact with the side wall surface 313 of the counter-pressurization side (L) in the assembly groove 310, most of the resistance acting on the sealing gasket 100 due to pressure from the pressurization side (H) is generated by the side wall surface 313. Therefore, the resistance generated by the tapered surface 311a is reduced. Therefore, the self-sealing function obtained by compression between the tapered surface 311a and the inner circumferential surface of the mounting hole 210, in the vicinity opposite to the tapered surface 311a, is reduced compared to the case of this embodiment.

[0062] In summary, according to the sealing structure of this embodiment, even if the creep phenomenon of the sealing gasket 100 is promoted due to long-term use and thermal shrinkage is aggravated over time, the self-sealing function is fully utilized, thereby enabling stable sealing performance over a long period of time.

[0063] Furthermore, in this embodiment, the side wall 312 of the pressure side (H) in the assembly groove 310 is formed by a surface perpendicular to the central axis of the sealing gasket 100, and a structure is adopted in which a gap S is provided between the side wall 313 of the counter-pressure side (L) in the assembly groove 310 and the sealing gasket 100. This improves the ease of assembly of the sealing gasket 100 into the assembly groove 310. This aspect is addressed as described in the assembly method of the sealing structure above.

[0064] Furthermore, in this embodiment, the front end of the annular protrusion 311 is positioned such that it is offset towards the pressure side (H) from the center in the groove width direction of the mounting groove 310. Therefore, in the outer peripheral surface of the gasket 100, particularly near the pressure side (H), gaps between it and the inner peripheral surface of the mounting hole 210 can be suppressed. Thus, even in the gasket 100 where creep is exacerbated, under low-temperature conditions, the gap formed between the outer peripheral surface of the gasket 100 and the inner peripheral surface of the mounting hole 210 can be narrowed near the pressure side (H). Therefore, by narrowing the gap formed in the outer peripheral surface of the gasket near the pressure side (H) and the inner peripheral surface of the mounting hole 210, leakage of the fluid in the sealed object can be suppressed compared to a wider gap. This aspect will be explained in more detail based on the evaluation tests described below.

[0065] The following describes the evaluation tests (leakage tests) and results related to the sealing gasket of this embodiment. Figures 5-9 Please provide an explanation. For example... Figure 5As shown, the evaluation test apparatus includes: a constant temperature bath 510; a fixture 200X for the mounted component, mimicking the structure near the mounting holes of the cylinder head; a fixture 300X for the mounting component, mimicking the injector; a pump 520 for supplying nitrogen gas; and a flow meter 530 for measuring leakage. By using this evaluation test apparatus, the leakage of the sealing fluid (combustion gas) when the injector is mounted on the cylinder head can be evaluated.

[0066] The mounting component fixture 200X has a mounting hole 210X. Additionally, the mounting component fixture 300X has a mounting groove 310X for assembling the sealing gasket 100. In the evaluation test, the mounting component fixture 300X, with the sealing gasket 100 assembled in the mounting groove 310X, is mounted in the mounting hole 210X. In this state, high-pressure nitrogen gas is supplied from the pump 520 to the mounting hole 210X, and the flow rate of nitrogen gas leaking from the transverse hole 220X formed in the mounting component fixture 200X is measured using a flow meter 530, thereby determining the leakage amount.

[0067] In the evaluation test, to fully exacerbate the creep phenomenon of the PTFE gasket 100, high-pressure (14 MPa) nitrogen gas was supplied to the mounting hole 210X for a specified time while the temperature in the constant temperature bath 510 was set to 230°C. Subsequently, the leakage rate was measured while the temperature in the constant temperature bath 510 was set to -40°C and nitrogen gas at 8 MPa was supplied to the mounting hole 210X. It should be noted that "-40°C" is set based on the lowest temperature within the actual operating environment temperature range.

[0068] Regarding the mounting component fixture 300X, a comparative example is given for the assembly slot 310X, where the bottom surface of the slot only has a tapering surface that expands from the high-pressure side towards the low-pressure side (refer to the background art description), and another example is given for the annular protrusion 311 located in the center of the slot width (in...). Figure 2 In the case of W32 / W31 = 0.5, and in this embodiment where the annular protrusion 311 is biased towards the high-pressure side (H) Figure 2 An evaluation experiment was conducted when W32 / W31 = 0.2.

[0069] As a result, in the existing example, the leakage rate at low temperature is approximately 3000 cc / min. In contrast, in the comparative example, the leakage rate at low temperature is approximately 60 cc / min, while in this embodiment, almost no leakage at low temperature was detected. The difference in leakage rate between the comparative example and this embodiment is based on the following considerations. That is, when the creep phenomenon of the sealing gasket 100 is sufficiently intensified, the gap between the outer peripheral surface of the sealing gasket 100 and the inner peripheral surface of the mounting hole 210X is narrowest (or there is no gap) near the front end of the annular protrusion 311, and gradually widens as it moves away from the front end of the annular protrusion 311 in the axial direction. The wider this gap is on the pressurized side (H), the easier it is for leakage to occur. Therefore, in the case of this embodiment, this gap in the pressurized side (H) can be narrowed, and therefore, compared with the comparative example, it is believed that the leakage rate can be reduced.

[0070] Furthermore, the aforementioned evaluation tests were conducted using samples with various changes to the dimensions of the parts related to the sealing gasket 100 and the annular protrusion 311, thereby verifying the appropriate dimensions of each part. The verification results are described below. It should be noted that the reference dimensions of the samples used in the evaluation tests are as follows. Regarding the sealing gasket 100, Figure 1 In the figures, W10 = 3.09mm, D11 = 4.68mm, and D12 = 5.97mm. Additionally, the inner diameter D20 of mounting hole 210X is 6.2575mm. Regarding the annular groove 310X, Figure 2 The dimensions are W31 = 3.7mm, W32 = 0.74mm, D31 = 5.975mm, D32 = 4.89mm, and D33 = 5.175mm.

[0071] To verify the relationship between the position of the front end of the annular protrusion 311 and the leakage amount, evaluation tests were conducted on multiple samples (mounting component fixture 300X) with altered positions of the front end of the annular protrusion 311 (changing W32 / W31). It should be noted that the evaluation tests were conducted using samples where only W32 / W31 differed, while other dimensions remained the same (the dimensions of the aforementioned reference), by varying the taper angles of the taper surfaces 311a and 311b. Figure 6 This is a graph showing the evaluation results, with the horizontal axis representing the leakage rate at low temperatures [cc / min] and the vertical axis representing W32 / W31. The evaluation results indicate that, to meet the requirement of a leakage rate below 10 cc / min without quality issues, W32 / W31 should be approximately 0.1 or higher and below 0.45.

[0072] In addition, to verify the relationship between the compression allowance and leakage of the gasket 100, evaluation tests were conducted on multiple samples with only the outer diameter D12 of the gasket 100 changed. It should be noted that "compression allowance" is equivalent to the thickness of the gasket 100 minus the minimum clearance at the assembly point of the gasket 100. Therefore, "compression allowance" = (D12 - D11) / 2 - (D20 - D33) / 2 (refer to...) Figure 1 and Figure 2 ). Figure 7 This is a graph showing the evaluation results, with the horizontal axis representing the leakage rate at low temperatures [cc / min] and the vertical axis representing the compression margin. The evaluation results indicate that, to meet the requirement of a leakage rate below 10cc / min without quality issues, a compression margin of approximately 0.05 mm or more and below 0.23 mm is sufficient.

[0073] Furthermore, to verify the relationship between the taper angle of the tapering surface 311a on the pressurized side (H) of the annular protrusion 311 and the leakage rate, evaluation tests were conducted on multiple samples with varying taper angles. It should be noted that by setting W31, W32 / W31 (=0.2), and D33 constant, and varying D32, evaluation tests were conducted using multiple samples with different taper angles of the tapering surface 311a (see reference). Figure 2 ). Figure 8 This is a graph showing the evaluation results, with the horizontal axis representing the leakage rate at low temperatures [cc / min] and the vertical axis representing the taper angle. The evaluation results indicate that, to meet the requirement of a leakage rate below 10cc / min without quality issues, a taper angle of approximately 25° to 48° is sufficient.

[0074] Furthermore, to verify the relationship between the gap S (the gap when no fluid pressure is applied) between the side wall 313 of the counter-pressurized side (L) formed in the assembly groove 310 and the sealing gasket 100 and the leakage amount when fluid pressure is applied, evaluation tests were conducted on multiple samples with altered axial dimensions (W10) of the sealing gasket 100. It should be noted that for the annular protrusion 311, W32 / W31 was set to 0.2. Figure 9 This is a graph showing the evaluation results, with the horizontal axis representing the leakage rate at low temperatures [cc / min] and the vertical axis representing the gap S. The evaluation results indicate that, to meet the requirement of a leakage rate below 10cc / min without quality issues, a gap S of approximately 0.17mm or more is sufficient.

[0075] Explanation of reference numerals in the attached figures

[0076] 100 sealing gasket

[0077] 200 Installed components

[0078] 200X Installed component clamp

[0079] 210, 210X mounting holes

[0080] 220X horizontal hole

[0081] 300 mounting components

[0082] 300X Mounting Component Fixture

[0083] 310, 310X Assembly Slots

[0084] 311 ring-shaped protrusions

[0085] 311a (Pressure side) tapering surface

[0086] 311b (counter-pressure side) tapering surface

[0087] 312 (Pressurized side) sidewall

[0088] 313 (Reverse Pressure Side) Side Wall

[0089] 510 constant temperature bath

[0090] 520 pump

[0091] 530 Flow Meter

[0092] S-gap

Claims

1. A sealing structure, comprising: The component to be installed has mounting holes; The mounting component is installed in the mounting hole; and A cylindrical resin gasket, through an annular gap disposed between the mounting hole and the mounting component, seals the pressure side (high pressure due to the pressure of the fluid being sealed) and the counter-pressure side (opposite to the pressure side). The sealing structure is characterized in that... The mounting component is provided with an annular mounting groove for assembling the resin sealing gasket. An annular protrusion is provided at the bottom of the assembly groove, and the annular protrusion has a first tapering surface that expands from the pressurizing side toward the counter-pressurizing side; And a second tapering surface that tapers from the pressurizing side toward the counter-pressurizing side, the front end of the annular protrusion being positioned offset toward the pressurizing side from a position greater than the center of the groove in the width direction of the assembly groove. The taper angle of the first tapering surface is larger than that of the second tapering surface. The axial length of the mounting component of the first tapered surface is shorter than the axial length of the second tapered surface.

2. The sealing structure according to claim 1, characterized in that, The resin sealing gasket is assembled in the assembly groove at a position biased towards the pressurized side, and when no pressure is applied from the pressurized side, a gap is provided between the side wall of the counter-pressurized side in the assembly groove and the resin sealing gasket.

3. The sealing structure according to claim 1 or 2, characterized in that, The sidewall of the pressurized side in the assembly groove is formed by a surface perpendicular to the central axis of the resin gasket.

4. The sealing structure according to claim 3, characterized in that, The sidewall of the pressurized side in the assembly groove is formed by a surface perpendicular to the central axis of the resin gasket, and the sidewall of the counter-pressurized side in the assembly groove is formed by a surface perpendicular to the central axis of the resin gasket. The tapered surface of the annular protrusion is connected to the sidewall of the pressurized side by a curved surface, and the tapered surface of the annular protrusion is connected to the sidewall of the counter-pressurized side by a curved surface.

5. A method for assembling a sealing structure, as described in claim 1, 2, 3, or 4, characterized in that the method comprises: The process of assembling the resin seal into the mounting groove after the resin seal is inserted into the mounting component from the pressure side, and then sliding the resin seal toward the mounting groove until the end face of the resin seal on the pressure side passes through the side wall of the pressure side in the mounting groove; and The process of installing the mounting component, which is fitted with the resin sealing gasket, into the mounting hole of the component to be mounted.

Images