Fireproof check valve

Abstract

The utility model relates to a fireproof check valve which comprises a valve body, a valve seat and a valve plate, the valve body is provided with a fixing support at the edge of the valve seat, and a forced closing piece and a second elastic piece acting on the forced closing piece are installed on the fixing support. The fusing assembly is provided with fusing points on the range hood side and the flue side, so that the fusing assembly can be in a fusing state when any side is on fire, the forced closing piece is separated from the fusing assembly, and the valve plate is forcibly closed under the action of the second elastic piece. The utility model has the advantages that: the fusing assembly is designed into a double-fusing mechanism, and both the air inlet surface and the air outlet surface can meet the fire-resistant and fusing requirements.

Description

TECHNICAL FIELD

[0001] The utility model relates to a fire valve, especially a fire check valve for a chimney of a range hood. BACKGROUND

[0002] The chimney check valve is a valve for preventing backflow in the chimney system, which is usually arranged in the smoke system, such as the exhaust structure of a kitchen. The chimney check valve is arranged on the air outlet of the range hood to prevent the oil fume sucked from the range hood from flowing back into the kitchen. The existing chimney check valve is usually hingedly connected to the chimney outlet. When the oil fume is discharged through the chimney, the pressure generated by the flow of the oil fume in the chimney lifts the chimney check valve, so that the chimney check valve rotates relative to the chimney outlet, thereby opening the outlet to allow the oil fume to be discharged from the chimney outlet. After the oil fume is completely discharged, the pressure disappears, and the chimney check valve returns to the position before rotation by gravity or the elastic force of the first elastic member, thereby closing the chimney outlet.

[0003] The ordinary chimney check valve closes the valve port by a rotatable valve plate. In the existing patent with the patent number ZL201711086467.2, the first clamping rod and the second clamping rod of the check valve are separated from the temperature control plate under the condition of chimney fire. The first clamping rod and the second clamping rod move downward along the corresponding guide groove under the action of the respective tension spring to close the first valve plate and the second valve plate. However, in actual use, the guide groove may be detached due to the pressure of the tension spring, causing the valve plate to open and jam. In addition, the fuse plate of the fire check valve is usually a single-sided fuse plate (i.e., located on the side of the chimney prone to fire), which is easy to cause the chimney side of the range hood to catch fire. Due to the limitation of the position of the fuse plate, the fuse cannot be triggered when the check valve is in the check state, which cannot meet the standard requirements. SUMMARY

[0004] The first technical problem to be solved by the utility model is to provide a fire check valve that can meet the requirements of fire resistance and fuse breaking regardless of whether the chimney side or the chimney side catches fire.

[0005] The second technical problem to be solved by the utility model is to provide a fire check valve that can tightly close the valve plate at the opening under the condition of fire.

[0006] The technical solution adopted by the utility model to solve the above-mentioned first technical problem is as follows: the fire check valve comprises a valve body, an inlet end for the flow of oil fume, and an outlet end for the flow of oil fume.

[0007] A valve seat is arranged in the valve body adjacent to the inlet end and has an opening in fluid communication with the inlet end and the outlet end.

[0008] a valve plate pivotally attached to the valve seat and configured to open and close the opening of the valve seat for realizing directional flow and sealing function with the valve body; and

[0009] a fixed support arranged at the edge of the valve seat of the valve body, a forced closing member and a second elastic member acting on the forced closing member being mounted on the fixed support;

[0010] characterized in that:

[0011] the valve seat is provided with a fuse assembly adjacent to the fixed support, the fuse assembly being provided with a fuse point on both the side of the smoke machine and the side of the flue, so that in the state of fire on either side, the fuse assembly can be in the state of fusion, and the forced closing member is separated from the fuse assembly and forced to close the valve plate under the action of the second elastic member.

[0012] In order to realize that the fuse assembly is provided with a fuse point on both the side of the smoke machine and the side of the flue, and considering the simple structure, preferably, the fuse assembly comprises a support and a fuse plate arranged on the side of the flue, the support at least partially passes through the valve seat in the direction of the side of the smoke machine, and is provided with a fuse point at the corresponding position of the valve seat. The support can play a dual role, that is, it can set the fuse plate, and its own part passing through the valve seat and towards the side of the smoke machine can also serve as a fuse point, so that the fireproof check valve can meet the requirements of fire resistance and fusion regardless of the side of the smoke machine or the side of the flue.

[0013] In order to realize the "one thing two uses" function of the support, preferably, the cross section of the support is "L" shaped, comprising a first branch extending towards the side of the flue and a second branch arranged perpendicularly to the first branch, the second branch is provided with a mounting hole for connecting the fastener on the valve seat, and is provided with a fuse point adjacent to the mounting hole, and the fuse plate is arranged on the first branch.

[0014] In order to realize that the fuse plate can fix the forced closing member in the unfused state, preferably, the fuse plate comprises left and right fuse plates arranged side by side, and the left and right fuse plates are provided with clamping grooves that can jointly clamp the forced closing member.

[0015] As a second design scheme of the fuse plate, the fuse plate comprises left and right fuse plates arranged side by side, and the left and right fuse plates are provided with clamping grooves that can jointly clamp the forced closing member.

[0016] Further, the support is rod-shaped, the support passes through the valve seat, and is provided with a fuse point at the end of the support.

[0017] Further, the fuse piece is in an inverted "U" shape, comprising a first vertical part, a second vertical part and a horizontal part connecting the first vertical part and the second vertical part, and the three parts together form a clamping groove capable of clamping the forced closing member, the horizontal part is provided with an insertion part capable of inserting the end of the support, and the horizontal part is further provided with a third elastic member capable of restoring the fuse piece to the initial state in the fuse state.

[0018] As a third design of the fuse piece: the fuse piece is in an inverted "mountain" shape, comprising a first vertical part, a second vertical part and a horizontal part connecting the first vertical part and the second vertical part, and a third vertical part is provided on the horizontal part between the first vertical part and the second vertical part, and the first vertical part, the second vertical part and the third vertical part together form a clamping groove capable of clamping the forced closing member, the length of the third vertical part is longer than the first vertical part and the second vertical part to form an insertion part for inserting the end of the support, and the horizontal part is further provided with a fourth elastic member capable of restoring the fuse piece to the initial state in the fuse state.

[0019] To solve the second technical problem, preferably, the valve piece is provided with at least two protrusions capable of deforming the forced closing member to tightly close the valve piece at the opening of the valve seat. This design can make the valve piece more tightly closed at the opening of the valve seat.

[0020] Further, the forced closing member is in a rod shape, and the two sides of the fixed support are further respectively provided with a sliding support capable of sliding the forced closing member.

[0021] Further, the sliding support is provided with at least two clamping grooves, the end of the forced closing member can be engaged in the clamping grooves, and the groove opening of the clamping grooves is lower than the protrusions. The groove opening of the clamping grooves is provided to cooperate with the protrusions of the valve piece and to force the forced closing member to deform.

[0022] In order to avoid the sliding support from falling off due to the tension of the spring, preferably, the fixed support is provided with an auxiliary support capable of fixing the sliding support.

[0023] Further, the auxiliary support is provided with a socket, and correspondingly, the sliding support is provided with a sub-support capable of being inserted into the socket. By inserting the sub-support into the socket, the insertion and connection of the two can be conveniently achieved.

[0024] Further, the auxiliary support comprises a connecting section in the middle and a first branch section and a second branch section connected at both ends of the connecting section, the first branch section and the second branch section respectively extend outward and upward from the connecting section to form a laterally placed V shape, and the socket is respectively provided on the first branch section and the second branch section.

[0025] In order to avoid the valve plate from being stuck and opened due to oil pollution, preferably, the valve plate comprises a first valve plate and a second valve plate which are independently pivoted on the valve body through a common pivot shaft, and a first elastic member is arranged on the pivot shaft to enable each valve plate to always have a tendency to close the corresponding opening, wherein the first valve plate and / or the second valve plate are respectively provided with an acting part which can exert an opening force on each other under the action of oil fume, and the acting part is located below the forced closing member. The opening force of the first valve plate or the second valve plate can be increased by the arrangement of the acting part, so that the first valve plate and the second valve plate can be synchronously opened.

[0026] In order to facilitate the installation of the fuse assembly, preferably, a partition is arranged in the center of the valve seat to divide the opening into a first opening and a second opening, the first valve plate corresponds to the first opening, and the second valve plate corresponds to the second opening, and the bracket of the fuse assembly is arranged on the partition.

[0027] Compared with the prior art, the advantages of the utility model lie in that the fuse assembly is provided with a fuse point on the smoke machine side and the flue side, so that in the state of fire on any side, the fuse assembly can be in the state of fusion to drive the forced closing member to separate from the fuse assembly and to force the valve plate to close under the action of the second elastic member, therefore, the fuse assembly is designed as a double-fusion mechanism, and the air inlet and the air outlet surface can meet the requirements of fire resistance and fusion. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model;

[0029] Figure 2 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model when being installed towards the smoke machine side;

[0030] Figure 3 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model when being installed from another angle (showing the flue side);

[0031] Figure 4 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model in the state of valve plate closing;

[0032] Figure 5 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model in the state of valve plate opening;

[0033] Figure 6 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model showing the installation state of the fuse assembly;

[0034] Figure 7 It is a structural schematic view of the fireproof check valve in the embodiment 1 of the utility model showing the installation state of the fuse assembly; Figure 6Enlarged view of point D in the middle;

[0035] Figure 8 This is a schematic diagram of the fuse assembly in Embodiment 1 of this utility model;

[0036] Figure 9 This is a schematic diagram of the auxiliary support structure in Embodiment 1 of this utility model;

[0037] Figure 10 This is a partial schematic diagram of the fireproof check valve in Embodiment 1 of this utility model (showing that the forced closing element is confined in the fusible assembly);

[0038] Figure 11 This is a partial schematic diagram of the fireproof check valve in Embodiment 1 of this utility model (showing that the forced closing element is released from its position within the fusible assembly);

[0039] Figure 12 The first valve plate and the second valve plate interact in Embodiment 1 of this utility model;

[0040] Figure 13 This is a schematic diagram of the fuse assembly in its normal state in Embodiment 2 of this utility model;

[0041] Figure 14 This is a schematic diagram of the structure of the fusible assembly in Embodiment 2 of this utility model, in which the bracket passes through the valve seat and a fusible point is provided at the end of the bracket.

[0042] Figure 15 for Figure 13 A partial structural diagram (showing the fuse assembly in an unfused state);

[0043] Figure 16 for Figure 15 Enlarged view of point D in the middle;

[0044] Figure 17 This is a schematic diagram of the structure of the fusible assembly in the fusible state to close the valve plate, as shown in Embodiment 2 of this utility model;

[0045] Figure 18 This is a schematic diagram of the structure of the valve plate when the fusible component is in an unfusible state, as shown in Embodiment 3 of this utility model;

[0046] Figure 19 This is a schematic diagram of the structure of the fuse assembly in the fuse-broken state as shown in Embodiment 3 of this utility model;

[0047] Figure 20 This is a schematic diagram of the structure of the fuse in Embodiment 3 of this utility model. Detailed Implementation

[0048] The utility model will be further described in detail below in combination with the drawings.

[0049] Example 1

[0050] As Figures 1-12 shown, it is the best embodiment of the utility model. The fireproof check valve of the embodiment comprises a valve body 1, a valve seat 2 and a valve piece, wherein the valve body 1 has an inlet end 11 for oil fume inflow and an outlet end 12 for oil fume outflow, the valve seat 2 is arranged at the position adjacent to the inlet end 11 in the valve body 1 and has an opening in fluid communication with the inlet end 11 and the outlet end 12, and the valve piece pivotally attached on the valve seat 2 is configured to open and close the opening of the valve seat 2 for realizing the directional flow and sealing function with the valve body 1; wherein the valve body 1 is provided with a fixed support 4 at the edge of the valve seat 2, a forced closing piece 7 and a second elastic piece 5 acting on the forced closing piece 7 are installed on the fixed support 4, and a fuse assembly 6 is arranged at the position adjacent to the fixed support 4 of the valve seat 2, the fuse assembly 6 is provided with a fuse point 61 at the smoke machine side A and the flue side B, so that in the state of fire at any side, the fuse assembly 6 can be in the state of fusion, the forced closing piece 7 is separated from the fuse assembly 6 and forcibly closes the valve piece under the action of the second elastic piece 5, the fuse assembly 6 is designed as a double fuse mechanism design, and both the inlet and outlet surfaces can meet the requirements of fire resistance and fusion.

[0051] Specifically, in order to realize that the fuse assembly 6 is provided with a fuse point 61 on both the hood side A and the flue side B, and from the perspective of simple structure, the fuse assembly 6 of the present embodiment includes a bracket 62 and a fuse link arranged on the flue side B, the bracket 62 at least partially penetrates the valve seat 2 in the direction towards the hood side A and is provided with a fuse point 61 at the corresponding position of the valve seat 2. The bracket 62 can serve two purposes, one is to arrange the fuse link, and the other is that the part of the bracket 62 itself which penetrates the valve seat 2 and faces the hood side A can serve as a fuse point 61, so as to realize a fireproof check valve which can meet the fireproof and fuse requirements no matter whether the fire occurs on the hood side A or the flue side B. In addition, in order to realize the "one thing with two uses" of the bracket 62, the bracket 62 is designed in an "L" shape in cross section, including a first branch arm 64 extending towards the flue side B and a second branch arm 65 arranged perpendicularly to the first branch arm 64, the second branch arm 65 is provided with a mounting hole 66 for connecting the fastener to the valve seat 2, and the fuse point 61 is arranged adjacent to the mounting hole 66, and the fuse link is arranged on the first branch arm 64. The valve disc of the fireproof check valve can be arranged as a single valve disc or a double valve disc. Taking the double valve disc as an example, the valve disc includes a first valve disc 3c and a second valve disc 3d which are pivotally connected to the valve body 1 by a common pivot shaft and are relatively independent, and a first elastic member 3e is arranged on the pivot shaft to enable each valve disc to always have a tendency to close the corresponding opening. An acting portion is further arranged on the first valve disc 3c and / or the second valve disc 3d to exert an opening force on each other under the action of the oil fume, and the acting portion is located below the forced closing member 7. The arrangement of the acting portion can increase the opening force of the first valve disc 3c or the second valve disc 3d, so as to achieve the purpose of synchronous opening of the first valve disc 3c and the second valve disc 3d. Referring to the drawings, the acting portion of the first valve disc 3c is a plate-shaped pressing plate, the lower surface of the pressing plate abuts against the horizontal section of the acting portion of the second valve disc 3d, and in the state that the free end of the pressing plate slides to the end of the horizontal section of the second valve disc 3d, the first valve disc 3c can exert a force on the second valve disc 3d with the end as a fulcrum, pry the second valve disc 3d and cause the synchronous rotation and opening of the two. Under the action of the oil fume, the force is transmitted to the first valve disc 3c, and after sliding along the horizontal section of the second valve disc 3d to the end thereof, the opening force of the second valve disc 3d is increased, so as to pry the second valve disc 3d and cause the synchronous rotation and opening of the two. Conversely, the same purpose can be achieved. In order to facilitate the installation of the fuse assembly 6, the central part of the valve seat 2 is provided with a partition 23 which divides the opening into a first opening 21 and a second opening 22, the first valve disc 3c corresponds to the first opening 21 and the second valve disc 3d corresponds to the second opening 22, and the bracket 62 of the fuse assembly 6 is arranged on the partition 23.

[0052] And the corresponding first valve piece 3c and second valve piece 3d, also respectively and side by side with the left and right fuses a and b, and the left and right fuses a and b are provided with a clamping groove 63 that can clamp the forced closing piece 7 together, so that the fuse can fix the forced closing piece 7 in the un-fused state, in addition, each valve piece is provided with at least two protrusions 30, the protrusions 30 can make the forced closing piece 7 deform and tightly close the valve piece at the opening of the valve seat 2, and the forced closing piece 7 is in the form of a rod, and the two sides of the fixed support 4 are also respectively provided with a sliding support 9 that can slide the forced closing piece 7, and each sliding support 9 is provided with at least two clamping grooves 620, the end of the forced closing piece 7 can be engaged in the clamping groove 620, and the slot of the clamping groove 620 is lower than the protrusion 30. The slot of the clamping groove 620 is set to cooperate with the protrusion 30 of the valve piece and force the forced closing piece 7 to deform.

[0053] The applicant also needs to emphasize that in order to avoid the sliding support 9 from falling off due to the tension of the spring, the fixed support 4 is provided with an auxiliary support 8 that can fix the sliding support 9, and the auxiliary support 8 is provided with a socket 83, and correspondingly, the sliding support 9 is provided with a sub-support 10 that can be inserted into the socket 83, and by inserting the sub-support 10 into the socket 83, the two can be conveniently connected. The auxiliary support 8 includes a connecting section in the middle and a first branch 81 and a second branch 82 connected at both ends of the connecting section, and the first branch 81 and the second branch 82 respectively extend outward and upward from the connecting section to form a side V-shaped letter, and the socket 83 is respectively arranged on the first branch 81 and the second branch 82.

[0054] In summary, the working process of the fireproof check valve is as follows: first, the fireproof check valve is installed on the wall surface, and the installation position is adjusted; when the fireproof check valve is opened, the first valve piece 3c and the second valve piece 3d are forced to open to discharge oil fumes under the action of oil fumes; when the fireproof check valve is closed, the first valve piece 3c and the second valve piece 3d are tilted and fall on the valve seat 2 under the action of their own gravity and the first elastic member 3e; when the temperature of the flue side B or the smoke machine side A is too high, the fuse assembly 6 is fused, and the forced closing piece 7 forces the first valve piece 3c and the second valve piece 3d to close under the action of the second elastic member 5, so as to avoid the spread of fire; if one of the first valve piece 3c and the second valve piece 3d is stuck by oil when they are opened, such as the second valve piece 3d, the free end of the pressure plate 3f of the first valve piece 3c can be slid to the end of the horizontal section 3g of the second valve piece 3d, and the first valve piece 3c can apply force to the second valve piece 3d with the end as a fulcrum, so as to pry the second valve piece 3d and rotate synchronously to open (such as Figure 12 ).

[0055] Example 2

[0056] The structure of the fuse link in this embodiment is basically the same as that in Embodiment 1, except that the structure of the fuse link is different. In this embodiment, the structure of the fuse link is an inverted "U" shape, including a first vertical portion c, a second vertical portion d, and a horizontal portion e connecting the first vertical portion c and the second vertical portion d, and the three portions together form a clamping groove 63 capable of clamping the forced closing member. The horizontal portion e is provided with an insertion portion g capable of inserting the end portion of a bracket, and the horizontal portion e is further provided with a third elastic member f capable of restoring the fuse link to the initial state in the fuse state. The bracket 62 is in the shape of a rod, and the bracket passes through the valve seat 2 and is provided with a fuse point 61 at the end of the bracket. When a fire occurs, the temperature reaches the fuse temperature of the fuse point 61, the horizontal portion of the fuse link and the end portion of the bracket are fused, the fuse link is pulled back to the initial state by the third elastic member f, the forced closing member is separated from the clamping groove 63, and the forced closing member 7 closes the valve piece 30, as shown in Figures 13-17 .

[0057] Embodiment 3

[0058] The structure of the fuse link in this embodiment is basically the same as that in Embodiment 2, except that the structure of the fuse link is different. In this embodiment, the structure of the fuse link is an inverted "mountain" shape, including a first vertical portion c', a second vertical portion d', and a horizontal portion e' connecting the first vertical portion c' and the second vertical portion d', and a third vertical portion h' located between the first vertical portion c' and the second vertical portion d' is provided on the horizontal portion e'. The first vertical portion c', the second vertical portion d', and the third vertical portion f' together form a clamping groove capable of clamping the forced closing member. The length of the third vertical portion h' is longer than that of the first vertical portion c' and the second vertical portion d' to form an insertion portion g capable of inserting the end portion of a bracket, and the horizontal portion e' is further provided with a fourth elastic member f' capable of restoring the fuse link to the initial state in the fuse state. The bracket 62 is in the shape of a rod, and the bracket passes through the valve seat 2 and is provided with a fuse point 61 at the end of the bracket. When a fire occurs, the temperature reaches the fuse temperature of the fuse point 61, the horizontal portion e' of the fuse link and the end portion of the bracket are fused, the fuse link is pulled back to the initial state by the fourth elastic member f', the forced closing member is separated from the clamping groove, and the forced closing member 7 closes the valve piece 30, as shown in Figures 18-20 .

Claims

1. A fireproof check valve, comprising a valve body (1) having an inlet end (11) for the inflow of fume and an outlet end (12) for the outflow of fume; a valve seat (2) provided in the valve body (1) adjacent to the inlet end (11) and having an opening in fluid communication with the inlet end (11) and the outlet end (12); a valve flap pivotally attached to the valve seat (2) and configured to open and close the opening of the valve seat (2) for realizing the directional flow and sealing functions of the valve body (1); and a fixed support (4) provided at the edge of the valve body (1) at the valve seat (2), on which a forced closing member (7) and a second elastic member (5) acting on the forced closing member (7) are mounted; characterized in that: the valve seat (2) is provided with a fuse assembly (6) adjacent to the fixed support (4), the fuse assembly (6) is provided with a fuse point (61) on both the hood side (A) and the flue side (B), so that in the event of fire on either side, the fuse assembly (6) can be in a fused state, and the forced closing member (7) is separated from the fuse assembly (6) and forced to close the valve flap under the action of the second elastic member (5).

2. The fire-rated check valve of claim 1, wherein: the fuse assembly (6) comprises a support (62) and a fuse piece provided on the flue side (B), the support (62) at least partially passes through the valve seat (2) in the direction of the hood side (A), and a fuse point (61) is provided at the corresponding position of the valve seat (2).

3. The fire-rated check valve of claim 2, wherein: the cross section of the support (62) is "L" shaped, comprising a first branch (64) extending towards the flue side (B) and a second branch (65) perpendicular to the first branch (64), the second branch (65) is provided with a mounting hole (66) for connecting the valve seat (2) with a fastener, and a fuse point (61) is provided adjacent to the mounting hole (66), and the fuse piece is provided on the first branch (64).

4. The fire-rated check valve of claim 3, wherein: the fuse piece comprises left and right fuse pieces (a) and (b) arranged side by side, and the left and right fuse pieces (a) and (b) are provided with clamping grooves (63) capable of clamping the forced closing member (7) together.

5. The fire-rated check valve of claim 2, wherein: the support (62) is rod-shaped, the support passes through the valve seat (2), and a fuse point (61) is provided at the end of the support.

6. The fire-rated check valve of claim 5, wherein: the fuse piece is inverted "U" shaped, comprising a first vertical part (c), a second vertical part (d) and a horizontal part (e) connecting the first vertical part (c) and the second vertical part (d), and the three parts together form a clamping groove capable of clamping the forced closing member, the horizontal part (e) is provided with an insertion part (g) capable of inserting the end of the support, and the horizontal part (e) is further provided with a third elastic member (f) capable of restoring the fuse piece to the initial state in the fused state.

7. The fire-rated check valve of claim 5, wherein: The fuse link is in an inverted "mountain" shape, comprising a first vertical part (c'), a second vertical part (d') and a horizontal part (e') connecting the first vertical part (c') and the second vertical part (d'), and a third vertical part (h') is arranged on the horizontal part (e') between the first vertical part (c') and the second vertical part (d'), and the first vertical part (c'), the second vertical part (d') and the third vertical part (h') together form a clamping groove capable of clamping the forced closing member, the length of the third vertical part (h') is longer than the first vertical part (c') and the second vertical part (d') to constitute an insertion part (g) for inserting the end of the support, and a fourth elastic member (f') capable of restoring the fuse link to the initial state under the fuse state is further arranged on the horizontal part (e').

8. The fire-rated check valve according to any one of claims 1 to 7, wherein: At least two protrusions (30) are arranged on the valve plate, which can deform the forced closing member (7) to tightly close the valve plate at the opening of the valve seat (2).

9. The fire-rated check valve of claim 8, wherein: The forced closing member (7) is in a rod shape, and the two sides of the fixed support (4) are respectively provided with a sliding support (9) capable of sliding the forced closing member (7).

10. The fire-rated check valve of claim 9, wherein: At least two clamping grooves (620) are arranged on the sliding support (9), and the end of the forced closing member (7) can be engaged in the clamping groove (620), and the groove opening of the clamping groove (620) is lower than the protrusion (30).

11. The fire-rated check valve of claim 10, wherein: The fixed support (4) is provided with an auxiliary support (8) capable of fixing the sliding support (9).

12. The fire-rated check valve of claim 11, wherein: The auxiliary support (8) is provided with a socket (83), and correspondingly, the sliding support (9) is provided with a sub-support (10) capable of being inserted into the socket (83).

13. The fire-rated check valve of claim 12, wherein: The auxiliary support (8) comprises a connecting section in the middle and a first branch (81) and a second branch (82) connected at both ends of the connecting section, the first branch (81) and the second branch (82) respectively extend outward and upward from the connecting section to form a side V-shaped type, and the socket (83) is arranged on the first branch (81) and the second branch (82) respectively.

14. The fire-rated check valve according to any one of claims 3-7, wherein: The valve plate comprises a first valve plate (3c) and a second valve plate (3d) which are relatively independently pivoted on the valve body (1) through a common pivot shaft, and a first elastic member (3e) capable of making each valve plate always have a tendency to close its corresponding opening is arranged on the pivot shaft, wherein the first valve plate (3c) and / or the second valve plate (3d) are respectively provided with an action part capable of exerting an opening action force on each other under the action of oil fume, and the action part is below the forced closing member (7).

15. The fire-rated check valve of claim 14, wherein: A divider (23) is arranged in the center of the valve seat (2) to divide the opening into a first opening (21) and a second opening (22), the first valve plate (3c) corresponds to the first opening (21) and the second valve plate (3d) corresponds to the second opening (22), and the support (62) of the fuse assembly (6) is arranged on the divider (23).

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