CN208749989U - Two way seal switching device and gas filter - Google Patents

Abstract

The utility model discloses a kind of two way seal switching device and gas filters, two way seal switching device includes cylinder, lid and sealing ring, lid includes fixed lid and the lug boss set on fixed lid side, sealing ring is sheathed on outside lug boss, the inner hole of cylinder includes the first hole section set gradually, second hole section and third hole section, first hole section is matched with fixed lid, second hole section is matched with sealing ring, third hole section is matched with lug boss, transition joint face between first hole section and the second hole section is first end face, the inner wall of first hole section is circumferentially spaced to be equipped at least two first latching tooths, the outer edge of fixed lid has the second latch being correspondingly arranged with first latching tooth, gap between the inner wall of second hole section and the outer wall of sealing ring is not more than 0.6mm.By above structure, radial deformation can be generated when sealing ring is compressed axially, and support on the inner wall of the second hole section, then sealing ring axially, is radially being squeezed, it can be achieved that assembling to cylinder and lid sufficiently sealed at this time.

Description

Two way seal switching device and gas filter

Technical field

The utility model relates to construction of pressure vessel technical fields, more particularly to a kind of two way seal switching device and combustion Air filter.

Background technique

Pressure vessel is widely used in industrial processes.By taking gas filter as an example, belong to pressure One of container, in combustion gas high pressure (0.4Mpa < P < 4.0Mpa), middle pressure (0.01Mpa≤P≤0.4Mpa), low pressure (P < It 0.01Mpa) is widely used in air supply system, plays purifying gas, protective conduit and equipment, promote burning quality, improve the energy The effect of utilization efficiency.It is filter plant indispensable in gas transmission and distribution production.

Currently, conventional pressure vessel seal form mostly uses bolt fastening to connect with cylinder ontology, exist dismounting it is difficult, The defects of maintenance operating time is long, equipment is heavy, brings inconvenience to production maintenance.Meanwhile it need to be in sealing flange piece Upper processing water wave line causes processing technology complicated, and machining accuracy control is difficult, and abrasion is easy to appear during production run Consumption, there are certain leakage hidden danger.

On sealing principle, conventional flange piece bolt matable pressure vessel relies on and is bolted compression lip packing washer It is sealed, but when unlatching maloperation with pressure occurs in production run, is easy to happen safety accident, cause people, wealth loss.

Summary of the invention

Based on this, the utility model lies in that overcoming the deficiencies of the prior art and provide a kind of anti-leak, fool proof two-way Enclosed switch device and gas filter.

Its technical solution is as follows:

A kind of two way seal switching device, including cylinder, lid and sealing ring, the lid include fixed cover and set on institute The lug boss of fixed lid side is stated, the sealing ring is sheathed on outside the lug boss, and the inner hole of the cylinder includes setting gradually The first hole section, the second hole section and third hole section, first hole section matches with the fixed lid, second hole section with it is described Sealing ring matching, the third hole section are matched with the lug boss, the transition between first hole section and second hole section Joint face is first end face, and the inner wall of first hole section is circumferentially spaced to be equipped at least two first latching tooths, the fixed lid Outer edge there is the second latch for being correspondingly arranged with the first latching tooth, formed and used between two adjacent first latching tooths In the bayonet for passing through second latch, is formed between the first latching tooth and the first end face and matched with second latch Clamping space, when second latch is located in the clamping space, the two sides up and down of the sealing ring are supported respectively to be set The inner wall of the fixed lid and the cylinder, the lateral surface of the sealing ring support the inner wall for setting second hole section.

Lid can be packed into cylinder by above-mentioned two way seal switching device, wherein fixed the second latch covered passes through by phase The bayonet formed between two adjacent first latching tooths, then by the fixed lid of rotation makes the second latch turn to first latching tooth and the Clamping space between one end face, after being packed into cylinder due to lid, sealing ring is matched with the second hole section, then sealing ring is by lid With the axial compression of cylinder, sealing ring can be sealed the cooperation between lid and cylinder, if be pressurized in cylinder at this time, lid Know from experience by the pressure far from cylinder direction, but since on the direction far from cylinder, the second latch can resist first latching tooth, protects The continuous extrusion to sealing ring is demonstrate,proved, can prevent above-mentioned two way seal switching device from leaking, and cylinder internal pressure is bigger, second Interaction force between latch and first latching tooth is bigger, causes the frictional force between lid and cylinder bigger, plays Self-fastening Effect, can prevent cylinder be pressurized when open lid maloperation, meanwhile, radial direction can be generated when sealing ring is compressed axially Deformation, the outer wall of sealing ring supports on the inner wall of the second hole section at this time, then at this time sealing ring it is axial, radially by It squeezes, when cylinder internal pressure is bigger, the pressure that sealing ring is subject to also is continuously increased, and the deformation of sealing ring further occurrence, makes at this time Sealing ring more pushes against fixed lid and cylinder in the axial direction, more push against the inner wall of the second hole section radially, then sealing ring Sealing effect is more preferable, it can be achieved that the effect that self-reinforcing seals.

Further, side of second latch far from the lug boss is mating surface, in the rotation of the fixed lid On direction, the front end of the mating surface is lozenges, and the rear end of the mating surface is bearing surface, the lozenges and horizontal plane Angular range is 0 °~60 °, and the bearing surface is horizontal plane.

Further, the angle of the lozenges and horizontal plane is 15 °.

Further, the transition joint face between second hole section and the third hole section is second end face, described the One latch is L1 close to the distance between the side of the first end face and the second end face, and the maximum of second latch is thick Degree is L2, and the axial width of the sealing ring is L3, wherein L1 < L2+L3.

Further, the distance between the first end face and the second end face are L4, wherein L4≤L3.

Further, the aperture of second hole section subtracts the difference of the outer diameter of the sealing ring no more than 0.6mm.

Further, the fixed side for covering the separate lug boss is additionally provided with handle.

Further, the first latching tooth is uniform intervals setting, and second latch is uniform intervals setting.

Further, the sealing ring is O-shaped washer.

A kind of gas filter switchs dress including air inlet pipe, escape pipe and the two way seal as described in above-mentioned any one It sets, the air inlet pipe, the escape pipe are connected to the cylinder, and the third hole section is equipped with and is connected to the air inlet pipe Air inlet, the third hole section are equipped with the gas outlet being connected to the escape pipe.

Above-mentioned gas filter, the cooperation between cylinder and lid can compress axially sealing ring, guarantee sealing ring Sealing effect be pressurized in cylinder, the second latch can at this time when gas is entered in cylinder and is discharged by discharge pipe by air inlet pipe First latching tooth is resisted, lid is prevented to be detached from cylinder, guarantees the continuous extrusion to sealing ring, can prevent above-mentioned gas filter from occurring Leakage, while as the intracorporal pressure of cylinder increases, the interaction force between the second latch and first latching tooth also increases with it, then Frictional force between cylinder and lid also constantly increases, and the maloperation of lid is opened when can prevent with pressure in cylinder.

Detailed description of the invention

Fig. 1 is the top view one of two way seal switching device described in the utility model embodiment；

Fig. 2 is the sectional view along A-A of Fig. 1；

Fig. 3 is the top view two of two way seal switching device described in the utility model embodiment；

Fig. 4 is the cross-sectional view of cylinder described in the utility model embodiment；

Fig. 5 is the top view of lid described in the utility model embodiment；

Fig. 6 is the partial enlarged view in Fig. 4 at B；

Fig. 7 is the cross-sectional view of lid described in the utility model embodiment；

Fig. 8 is the cross-sectional view of sealing ring described in the utility model embodiment.

Description of symbols:

100, cylinder, the 110, first hole section, 111, first latching tooth, 112, first end face, 113, bayonet, 114, clamping sky Between, the 120, second hole section, 121, second end face, 130, third hole section, 200, lid, 210, fixed lid, the 211, second latch, 211a, lozenges, 211b, bearing surface, 220, lug boss, 300, sealing ring, 400, handle.

Specific embodiment

The utility model is more fully retouched below with reference to relevant drawings for the ease of understanding the utility model, It states.The better embodiment of the utility model is given in attached drawing.But the utility model can come in many different forms It realizes, however it is not limited to embodiments described herein.On the contrary, the purpose of providing these embodiments is that making practical new to this The disclosure of type understands more thorough and comprehensive.

It should be noted that it can directly on the other element when element is referred to as " being fixed on " another element Or there may also be elements placed in the middle.When an element is considered as " connection " another element, it, which can be, is directly connected to To another element or it may be simultaneously present centering elements.Term as used herein " vertical ", " horizontal ", " left side ", " right side " and similar statement for illustrative purposes only, are not meant to be the only embodiment.

Unless otherwise defined, all technical and scientific terms used herein are led with the technology for belonging to the utility model The normally understood meaning of the technical staff in domain is identical.Terminology used in the description of the utility model herein only be The purpose of description specific embodiment, it is not intended that in limitation the utility model.Term as used herein "and/or" packet Include any and all combinations of one or more related listed items.

" first " described in the utility model, " second " do not represent specific quantity and sequence, are only used for title It distinguishes.

As shown in Figures 1 to 4, two way seal switching device includes cylinder 100, lid 200 and sealing ring 300, lid 200 include that fixed lid 210 and the lug boss 220 set on fixed 210 side of lid, sealing ring 300 are sheathed on outside lug boss 220, cylinder The inner hole of body 100 includes the first hole section 110, the second hole section 120 and third hole section 130 set gradually, the first hole section 110 with Fixed lid 210 matches, and the second hole section 120 is matched with sealing ring 300, and third hole section 130 is matched with lug boss 220, the first hole section 110 and the second transition joint face between hole section 120 be first end face 112, the inner wall of the first hole section 110 is circumferentially spaced to be equipped with The outer edge of at least two first latching tooths 111, fixed lid 210 has the second latch 211 being correspondingly arranged with first latching tooth 111, It is formed between two adjacent first latching tooths 111 for the bayonet 113 by the second latch 211, first latching tooth 111 and first Formation and the matched clamping space 114 of the second latch 211 between end face 112, when the second latch 211 is located in clamping space 114 When, the inner wall for setting fixed lid 210 and cylinder 100 is supported in the two sides up and down of sealing ring 300 respectively, and the lateral surface of sealing ring 300 supports If the hole wall of the second hole section 120.

Lid 200 can be packed into cylinder 100 by above-mentioned two way seal switching device, wherein the second latch on fixed lid 210 211 by the bayonet 113 by being formed between two adjacent first latching tooths 111, then by rotating fixed lid 210, makes the second card Tooth 211 turns to the clamping space 114 between first latching tooth 111 and first end face 112, since lid 200 is packed into cylinder 100 Afterwards, sealing ring 300 is matched with the second hole section 120, then axial compression of the sealing ring 300 by lid 200 and cylinder 100, sealing Circle 300 can be sealed the cooperation between lid 200 and cylinder 100, if be pressurized in cylinder 100 at this time, lid 200 can be by To the pressure far from 100 direction of cylinder, but since on the direction far from cylinder 100, the second latch 211 can resist first latching tooth 111, guarantee to prevent above-mentioned two way seal switching device from leaking, and in cylinder 100 continuous extrusion of sealing ring 300 Pressure is bigger, and the interaction force between the second latch 211 and first latching tooth 111 is bigger, cause lid 200 and cylinder 100 it Between frictional force it is bigger, play the role of Self-fastening, can prevent cylinder 100 be pressurized when open lid 200 maloperation, together When, radial deformation can be generated when sealing ring 300 is compressed axially, the outer wall of sealing ring 300, which supports, at this time is set to the second hole section On 120 inner wall, then at this time sealing ring 300 it is axial, be radially squeezed, it is close and when the pressure in cylinder 100 is bigger The pressure that seal 300 is subject to also is being continuously increased, at this time the deformation of sealing ring further occurrence, makes sealing ring 300 in the axial direction more Add the fixed lid 210 of abutting and cylinder 100, the inner wall for more pushing against the second hole section 120 radially, the then sealing of sealing ring 300 Effect is more preferable, it can be achieved that self-reinforcing sealing effect.

Optionally, the material of sealing ring 300 is rubber or metal etc..

Specifically, the first hole section 110 is set to one end of cylinder 100, and the other end of cylinder 100 is sealing structure, in cylinder 100, after lid 200 and sealing ring 300 assemble, closed cavity can be formed between lid 200 and sealing structure.When there is medium Into in cavity, the inner wall of cavity can be made to be pressurized.

Optionally, the internal diameter of the first hole section 110, the second hole section 120 and third hole section 130 is sequentially reduced.

Optionally, the quantity of first latching tooth 111 is equal with the quantity of the second latch 211.

Specifically, the quantity of first latching tooth 111 is three, after lid 200 and cylinder 100 are coupled at this time, by the The abutting of one latch 111 and the second latch 211 is realized to the circumferentially fixed of lid 200, and lid 200 can be prevented due to vibration etc. Reason rotates, and causes lid 200 to be detached from cylinder 100, it is ensured that the sealing effect of above-mentioned two way seal switching device.

Optionally, cylinder 100 and lid 200 can be the materials such as stainless steel, cast iron, cast steel or forged steel.

Specifically, cylinder 100 is rounded cylindrical structure, and fixed lid 210 is circular plate, and lug boss 220 is cylindric knot Structure, while the inner hole of cylinder 100 is round hole.Circumferential seal can be carried out to cylinder 100 and lid 200 at this time.

Specifically, when the second latch 211 is located in clamping space 114, the inner sidewall of sealing ring 300, which supports, is set to lug boss On 220 outer wall.Anti-leak can be further promoted at this time, and self-reinforcing sealing effect is more preferable.

Further, as shown in figure 5, side of second latch 211 far from lug boss 220 is mating surface, in the fixation On the direction of rotation of lid 210, the front end of above-mentioned mating surface is lozenges 211a, and the rear end of above-mentioned mating surface is bearing surface 211b, The angular range of lozenges 211a and horizontal plane is 0 °~60 °, and bearing surface 211b is horizontal plane.At this time when lid 200 and cylinder 100 when being coupled, and lozenges 211a can facilitate rotation lid 200 to screw in the second latch 211 in clamping space 114, realizes The clamping of first latching tooth 111 and the second latch 211, as the second latch 211 screws in the process in clamping space 114, sealing ring 300 are also gradually pressurized, while bearing surface 211b can guarantee when being pressurized in cylinder 100, and what the second latch 211 can be stable is against On one latch 111, guarantees that sealing ring 300 is pressurized everywhere, sealing effect is improved, when between lozenges 211a and horizontal plane When angle is excessive, will lead to first latching tooth 111 and the second latch 211, friction is small, therefore by lozenges 211a and horizontal Angular range between face is limited to 0 °~60 °, guarantees first latching tooth 111 and the second latch 211 when being pressurized in cylinder 100 Between frictional force it is larger, realize the Self-fastening effect of above-mentioned two way seal switching device.

Optionally, first latching tooth 111 includes cooperating lozenges and cooperation bearing surface close to the side of first end face 112, In, cooperation lozenges is arranged in parallel with lozenges 211a, and cooperation bearing surface is arranged in parallel with bearing surface 211b.It can further facilitate It is clamped by way of helical rotation between first latching tooth 111 and the second latch 211.

Further, the angle of lozenges 211a and horizontal plane is 15 °.Lid 200 and cylinder 100 can both have been facilitated at this time It is coupled, while the Self-fastening effect of above-mentioned two way seal switching device is preferable.

Further, as shown in Figure 6 to 8, the transition joint face between the second hole section 120 and third hole section 130 is the Biend 121, first latching tooth 111 are L1, the second card close to the distance between the side of first end face 112 and second end face 121 The maximum gauge of tooth 211 is L2, and the axial width of sealing ring 300 is L3, wherein L1 < L2+L3.At this time no matter in cylinder 100 Whether it is pressurized, sealing ring 300 can be further prevented above-mentioned two-way by the continuous extrusion of second end face 121 and lid 200 The leakage of enclosed switch device.

In the present embodiment, " axial direction " in the axial width of sealing ring 300 is the length direction of 300 central axis of sealing ring.

Optionally, the internal diameter of sealing ring 300 is less than the aperture of third hole section 130.Since the internal diameter of sealing ring 300 is less than The aperture of three hole sections 130, it is ensured that when cylinder 100 and lid 200 cause to squeeze to sealing ring 300, one of sealing ring 300 Divide and exceed second end face 121, when being pressurized in cylinder 100, pressure can force part of the sealing ring 300 beyond second end face 121 The inner wall for the third hole section 130 that is sticked simultaneously and fixed lid 210 play better seal effect close to the side of lug boss 220.

Further, as shown in Fig. 6 and Fig. 8, the distance between first end face 112 and second end face 121 are L4, wherein L4≧L3.The length of the second hole section 120 is less than the axial width of sealing ring 300 at this time, when lid 200 and the cooperation of cylinder 100, Sealing ring 300 stretches out the second hole section 120, and the fixation lid 210 of lid 200 can extrude sealing ring 300 at this time, guarantees sealing effect.

Optionally, 0.45mm≤L1-L2-L3≤0.33mm.Due in cooperation, therefore, to assure that sealing ring 300 is in quilt Squeezed state, but sealing ring 300 cannot cause failure since deformation is excessive simultaneously, and when 300 deformation of sealing ring is larger, It will lead to supporting for first latching tooth 111 and the second latch 211 and set tension, lid 200 is caused to be not easily disconnected from cylinder 100, therefore by L1- The numerical value of L2-L3 is set in above range, both can guarantee the sealing effect of sealing ring 300, while can prevent lid 200 and cylinder Dismounting between 100.

Specifically, L1-L2-L3=0.39mm.The achievable effect of sealing ring 300 is more preferable at this time.

Further, the aperture of the second hole section 120 subtracts the difference of the outer diameter of sealing ring 300 no more than 0.6mm.Test For personnel when the assembling structure to cylinder 100, lid 200 and sealing ring 300 is sealed test, discovery is when in cylinder 100 When pressure rises to certain numerical value, above-mentioned assembling structure can have the case where gas leakage, due in above-mentioned assembling structure, mainly by Sealing ring 300 plays the role of sealing anti-leak, therefore testing crew emphatically visits the parameter and state of sealing ring 300 Study carefully, it is thus found that can be generated between sealing ring 300 and first end face 112 when the pressure in cylinder 100 reaches certain numerical value Certain gap makes to form clearance channel between the inner wall and first end face 112 and sealing ring 300 of the second hole section 120, causes to let out The generation of leakage, for this purpose, testing crew proposition abuts the outer wall of sealing ring 300 and the inner wall of the second hole section 120, further to prevent Stopping leak leakage occurs, simultaneously because sealing ring 300 will receive extruding and deform, therefore second after the completion of above-mentioned assembling structure It can be interference fit, transition fit or clearance fit between hole section 120 and sealing ring 300, if but the second hole section 120 and sealing ring Gap between 300 cannot be excessive；Or the size of sealing ring 300 cannot be more too many greatly than the aperture of the second hole section 120, will affect dress Match, while after the completion of needing to guarantee above-mentioned assembling structure, the outer wall of sealing ring 300 can support the inner wall set on the second hole section 120, warp The research of overtesting personnel obtains being not more than when the gap between the inner wall of the second hole section 120 and the outer wall of sealing ring 300 When 0.6mm, for the sealing ring 300 in above-mentioned assembling structure by being squeezed and deformed, the outer wall of sealing ring 300, which can support, is set to the second hole On the inner wall of section 120, it can realize further seal at this time.

In the present embodiment, the outer diameter of sealing ring 300 is the outer diameter between sealing ring 300 is unassembled.

Further, as shown in Figures 1 and 3, fixed lid 210 is additionally provided with handle 400 far from the side of lug boss 220.It can Facilitate being coupled between lid 200 and cylinder 100.

Optionally, handle 400 and fixed lid 210 are hinged.

Further, first latching tooth 111 is uniform intervals setting, and the second latch 211 is uniform intervals setting.It at this time can be square Just being rotatably assorted between cylinder 100 and lid 200.

Optionally, the cross section of sealing ring 300 can be rectangle, circle or other shapes.

Further, as shown in figure 8, sealing ring 300 is O-shaped washer.The sealing effect of O-shaped washer is preferable, while being mark Quasi- part, cost is relatively low, and sealing ring 300, when being compressed axially, the deformation in the radial direction of sealing ring 300 is larger, can be more preferable Be against on the inner wall of the second hole section 120,

Specifically, the cross-sectional diameter of above-mentioned sealing ring 300 is 3.5mm.

In a specific embodiment, first latching tooth 111 is between the side and second end face 121 of first end face 112 Distance L1 be 11.9mm, the thickness L2 of fixed lid 210 is 8.79mm, and the cross-sectional diameter L3 of sealing ring 300 is 3.5mm, the The distance between one end face 112 and second end face 121 L4 are 3mm, and the outer diameter of sealing ring 300 is 129.41mm, lug boss 220 Outer diameter is 122.81mm, and the aperture of the second hole section 120 is 130.1mm, and the aperture of third hole section 130 is 123mm.

Because the outer diameter 129.41mm of sealing ring 300 works as sealing ring less than the aperture 130.1mm of the second hole section 120 300 with the second hole section 120 when matching, and its of sealing ring 300 radially and is not affected by compression.And in the axial direction of sealing ring 300, it is close The deflection of seal 300 is L1-L2-L3=0.39mm, therefore the deflection of sealing ring 300 in its axial direction is 0.39mm.By It is squeezed deformation in its axial direction in sealing ring 300, the cross section for inevitably resulting in sealing ring 300 becomes ellipse by circular deformation Circle, equal with oval perimeter according to circular perimeter, the deflection of left and right directions can be calculated in we.Calculating process is such as Under:

Oval perimeters formula: L=2 π b+4 (a-b), wherein a is oval major semiaxis, and b is semi-minor axis.

Circumference calculation formula: L=π d, wherein d is circular diameter.

It according to above-mentioned data, can learn: d=3.5mm, b=(3.5-0.39)/2=1.55mm；

Substitute into above-mentioned formula: π d=2 π b+4 (a-b)；

The π of 3.5 π=2.8+4a-6.22；

A=2.1mm.

Then the gap between the outer wall of sealing ring 300 and the inner wall of the second hole section 120 is a-d/2=0.4mm at this time.

Since when sealing ring 300 is not affected by extruding and generates deformation, the outer wall of sealing ring 300 is interior with the second hole section 120 Gap between wall is (130.1-129.41)/2mm=0.345mm, then after in sealing ring 300, deformation occurs, sealing ring 300 Lateral wall can be against on the inner wall of the second hole section 120, and secondary deformation occurs, and can further improve sealing effect.

Above-mentioned two way seal switching device can be applied in gas filter, and gas filter includes air inlet pipe, escape pipe And such as above-mentioned two way seal switching device, air inlet pipe, escape pipe be connected tos with cylinder 100, third hole section 130 equipped with into The air inlet of tracheae connection, third hole section 130 are equipped with the gas outlet being connected to escape pipe.

Above-mentioned gas filter, the cooperation between cylinder 100 and lid 200 can compress axially sealing ring 300, protect The sealing effect for demonstrate,proving sealing ring 300, when gas is entered in cylinder 100 by air inlet pipe and is discharged by discharge pipe, in cylinder 100 by Pressure, the second latch 211 can resist first latching tooth 111 at this time, and lid 200 is prevented to be detached from cylinder 100, guarantee to sealing ring 300 Continuous extrusion can prevent above-mentioned gas filter from leaking, while as the pressure in cylinder 100 increases, the second latch 211 Interaction force between first latching tooth 111 also increases with it, then the frictional force between cylinder 100 and lid 200 is also continuous Increase, the maloperation of lid 200 is opened when can prevent with pressure in cylinder 100.

Optionally, gas filter further includes the filter core for filtering combustion gas, and filter core is set in third hole section 130, and is filtered Core is connected to air inlet pipe.

Each technical characteristic of embodiment described above can be combined arbitrarily, for simplicity of description, not to above-mentioned reality It applies all possible combination of each technical characteristic in example to be all described, as long as however, the combination of these technical characteristics is not deposited In contradiction, all should be considered as described in this specification.

Above-described embodiments merely represent several embodiments of the utility model, the description thereof is more specific and detailed, But it cannot be understood as the limitations to utility model patent range.It should be pointed out that for the common skill of this field For art personnel, without departing from the concept of the premise utility, various modifications and improvements can be made, these are belonged to The protection scope of the utility model.Therefore, the scope of protection shall be subject to the appended claims for the utility model patent.

Claims (10)

1. a kind of two way seal switching device, which is characterized in that including cylinder, lid and sealing ring, the lid includes fixing Lid and the lug boss set on the fixed lid side, the sealing ring are sheathed on outside the lug boss, the inner hole packet of the cylinder The first hole section, the second hole section and third hole section set gradually is included, first hole section is matched with the fixed lid, and described second Hole section is matched with the sealing ring, and the third hole section is matched with the lug boss, first hole section and second hole section Between transition joint face be first end face, the inner wall of first hole section is circumferentially spaced to be equipped at least two first latching tooths, The outer edge of the fixed lid has the second latch being correspondingly arranged with the first latching tooth, two adjacent first latching tooths Between formed for being formed by the bayonet of second latch, between the first latching tooth and the first end face and described the The matched clamping space of two latches, when second latch is located in the clamping space, the two sides up and down of the sealing ring The inner wall for setting the fixed lid and the cylinder is supported in face respectively, and the lateral surface of the sealing ring, which supports, sets the interior of second hole section Wall.

2. two way seal switching device according to claim 1, which is characterized in that second latch is far from the protrusion The side in portion is mating surface, and on the direction of rotation of the fixed lid, the front end of the mating surface is lozenges, the mating surface Rear end be bearing surface, the angular range of the lozenges and horizontal plane is 0 °~60 °, and the bearing surface is horizontal plane.

3. two way seal switching device according to claim 2, which is characterized in that the angle of the lozenges and horizontal plane It is 15 °.

4. two way seal switching device according to claim 1, which is characterized in that second hole section and the third hole Transition joint face between section is second end face, side and the second end of the first latching tooth close to the first end face The distance between face is L1, and the maximum gauge of second latch is L2, and the axial width of the sealing ring is L3, wherein L1 < L2+L3。

5. two way seal switching device according to claim 4, which is characterized in that the first end face and the second end The distance between face is L4, wherein L4≤L3.

6. two way seal switching device according to claim 1-5, which is characterized in that the hole of second hole section Diameter subtracts the difference of the outer diameter of the sealing ring no more than 0.6mm.

7. two way seal switching device according to claim 1-5, which is characterized in that the fixed lid is far from institute The side for stating lug boss is additionally provided with handle.

8. two way seal switching device according to claim 1-5, which is characterized in that the first latching tooth is equal Even interval setting, second latch are uniform intervals setting.

9. two way seal switching device according to claim 1-5, which is characterized in that the sealing ring is O-shaped Washer.

10. a kind of gas filter, which is characterized in that including air inlet pipe, escape pipe and such as the claims 1-9 any one The two way seal switching device, the air inlet pipe, the escape pipe are connected to the cylinder, are set in the third hole section There is the air inlet being connected to the air inlet pipe, the third hole section is equipped with the gas outlet being connected to the escape pipe.