Fire prevention check valve with a locking mechanism and a flue system having the same

Abstract

The present invention discloses a fireproof check valve with a locking mechanism and a flue system having the same, including a fireproof check valve body. The fireproof check valve body has a flue gas passage. One end of the flue gas passage has an air inlet, and the opposite end is an air outlet end. A rotatable valve plate that can only open in the air outlet direction is provided in the flue gas passage or on the end surface of the air outlet end. A high-temperature closing device with a locking mechanism is provided on the fireproof check valve body, which can force the valve plate to close towards the air inlet side at a set temperature. A secondary locking mechanism for the high-temperature closing device is provided at a set position of the fireproof check valve body or the high-temperature closing device. The present invention performs secondary locking on the movable components of the high-temperature closing device of the fireproof check valve, further improving its safety.

Description

Technical Field

[0001] The present invention relates to a fireproof check valve with a locking mechanism used in a kitchen using a common flue and a flue system having the same. Background Art

[0002] In a kitchen using a longitudinal common flue, in order to prevent the fume in the flue from flowing back into the kitchen, a device such as a fireproof check valve with a locking mechanism is generally provided between the air outlet of the range hood and the common flue. The existing fireproof check valve with a locking mechanism generally includes a flue passage formed by a housing. The flue passage has opposite air inlets and air outlets. The air inlet is connected to the air outlet of the range hood, and the air outlet extends into the common flue. A closable valve plate is provided at the air outlet of the flue passage. The valve plate is one or two pieces hinged to the flue passage through a valve plate rotating shaft, and a high-temperature closing device capable of forcibly closing the valve plate is provided on the air outlet side. When the range hood is not in use, the valve plate is in the closed position due to its own gravity, covering the air outlet part; when the range hood is in use, the valve plate is in the open position, and the valve plate is away from the air outlet. The existing fireproof check valve with a locking mechanism generally has an elastic clip or elastic piece provided on the housing on the side facing the air outlet, and the fireproof check valve with a locking mechanism is clamped on the air inlet of the flue through the elastic clip or elastic piece. This installation and fixing method causes the fireproof check valve with a locking mechanism not to fit tightly with the flue wall surface and is easy to loosen, resulting in air leakage at the joint between the fireproof check valve with a locking mechanism and the air inlet of the flue; there is also an installation method of drilling holes in the flue wall surface and installing the fireproof check valve with a locking mechanism on the air inlet of the flue through screws. This installation and fixing method is easy to damage the tiles on the flue wall surface, and the tiles are cracked or have cracks; the above methods all have the problem that the installation and replacement of the fireproof check valve with a locking mechanism are inconvenient.

[0003] Meanwhile, since multiple users share a vertical common flue, once a fire breaks out in one household, a large amount of high-temperature harmful gases will pour into the vertical common flue. At this time, if the valve plate in the fireproof check valve with a locking mechanism is not closed in time, these large amounts of high-temperature harmful gases will enter the homes of users who are using the range hood through the flue passage of the fireproof check valve with a locking mechanism, thus threatening the lives of the residents. In the existing fireproof check valve with a locking mechanism, a high-temperature closing device that can force the valve plate to close towards the air inlet side at a set temperature is provided on the outer end face of the air outlet end. When the flue gas temperature in the common flue is in a very high emergency state and reaches the set warning temperature, the high-temperature closing device forces the valve plate in the open state to close. However, the high-temperature closing devices on the existing fireproof check valves with locking mechanisms all use the force of a spring to close the valve plate. When the high temperature in the common flue lasts for a certain period of time, the spring fails due to the high temperature, and the valve plate loses the restraining force of the spring and will be opened again. The high-temperature harmful gases will pour into the user's home, thus threatening the lives of the residents. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a fireproof check valve with a locking mechanism that secondary locks the movable parts of the high-temperature closing device of the fireproof check valve, so that the valve plate of the fireproof valve is always in a closed state; another technical problem to be solved by the present invention is to provide a flue system having the above-mentioned fireproof check valve.

[0005] To solve the above technical problems, the present invention includes a fireproof check valve body. The fireproof check valve body has a flue passage. One end of the flue passage has an air inlet, and the opposite end is an air outlet end. A rotatable valve plate that can only open towards the air outlet direction is provided in the flue passage or on the end face of the air outlet end. A high-temperature closing device with a locking mechanism that can force the valve plate to close towards the air inlet side at a set temperature is provided on the fireproof check valve body. Its structural feature is that a secondary locking mechanism for the high-temperature closing device is provided at the set part of the fireproof check valve body or the high-temperature closing device.

[0006] The secondary locking mechanism for the high-temperature closing device includes a fixed cylinder that can be installed at the set part of the fireproof check valve body or the high-temperature closing device. One end of the fixed cylinder is open. A compression spring is provided at the inner end of the fixed cylinder. A locking pin is sleeved on the compression spring, and the outer end part of the locking pin extends out of the open end of the fixed cylinder.

[0007] The outer end of the locking pin is in the shape of a tapered rod. The inner end of the locking pin has an annular platform adapted to the inner cavity shape of the fixed cylinder. A pin post is provided at the inner end of the annular platform. The outer end of the compression spring is sleeved on the pin post.

[0008] The high-temperature shut-off device with a locking mechanism includes a bracket installed on the outer end face of the end face. A support shaft is provided on the bracket, and a lock pressing disc is sleeved on the support shaft. A pressing disc spring is sleeved on the support shaft. The bracket is provided with a heat-melting sheet or a separated bimetallic sheet that can melt at a set temperature and extends towards the lock pressing disc. The pressing strip lock pressing disc and the heat-melting sheet or the bimetallic sheet are interlocked with each other.

[0009] One end of the support shaft close to the valve disc is hinged with a valve disc pressing strip. The lock pressing disc is arranged corresponding to the valve disc pressing strip. A sunken groove is provided at one end of the lock pressing disc facing the pressing disc spring. A hook that is buckled in the sunken groove is provided on the valve disc pressing strip. After the lock pressing disc disengages from the bimetallic sheet and presses towards the valve disc pressing strip, a mutually locking mechanism is formed between the lock pressing disc and the valve disc pressing strip.

[0010] The mutually locking mechanism is that the valve disc pressing strip is wedge-shaped at its hinged end after being opened. The corresponding end of the lock pressing disc and the valve disc pressing strip has a conical cavity. The valve disc pressing strip with a wedge-shaped hinged end and the valve disc pressing strip with a conical cavity form a wedge-shaped lock.

[0011] The high-temperature shut-off device with a locking mechanism includes a bracket installed on the outer end face of the end face. A support shaft is provided on the bracket. One end of the support shaft close to the valve disc is hinged with a valve disc pressing strip. A lock pressing disc corresponding to the valve disc pressing strip is sleeved on the support shaft. A pressing disc spring is sleeved on the support shaft. The bracket is provided with a heat-melting sheet or a separated bimetallic sheet that can melt at a set temperature and extends towards the lock pressing disc. The pressing strip lock pressing disc and the bimetallic sheet are interlocked with each other. An inwardly arranged valve disc pressing strip guiding groove is provided along the relative outer side of the lock pressing disc. A clamping groove is provided inside the valve disc pressing strip guiding groove. A hook that is buckled in the clamping groove is provided on the valve disc pressing strip.

[0012] The high-temperature shut-off device with a locking mechanism includes a bracket installed on the outer end face of the end face. The outer side face of the bracket inclines downward from top to bottom towards the lower part of the end face. A sliding groove arranged along its length direction is opened in the lower section of the outer side face of the bracket. A guiding shaft parallel to the outer side face is provided inside the bracket. A spring is sleeved on the guiding shaft. An opening and closing sliding block that extends into the inner side of the bracket and can slide along the sliding groove (27) is provided on the outer side face of the bracket. The inner end of the opening and closing sliding block is sleeved on the guiding shaft. The rear upper part inside the opening and closing sliding block contacts the spring. A fusing wire that enables the opening and closing sliding block to compress the spring upward is provided in the sliding groove below the opening and closing sliding block. After the fusing wire fuses, the opening and closing sliding block slides downward along the outer side face of the bracket under the action of the spring and gradually approaches the right end face of the end face. When the opening and closing sliding block stops sliding, the opening and closing sliding block just presses tightly on the two valve discs to completely block the double outlet of the end face.

[0013] The flue gas system of the present invention includes a common flue gas duct. A fire damper installation opening is provided at a set position of the common flue gas duct; the fire prevention and backflow prevention valve described above is installed in the fire damper installation opening.

[0014] After adopting the above structure, since a high-temperature closing device with a locking mechanism is provided on the fire and backflow prevention valve body, which can force the valve plate to close towards the air inlet side at a set temperature, and a secondary locking mechanism for the high-temperature closing device is provided at a set position of the fire and backflow prevention valve body or the high-temperature closing device to perform secondary locking on the movable components of the high-temperature closing device of the fire and backflow prevention valve to improve its safety. When the flue gas temperature in the common flue is in a very high emergency state and reaches the set warning temperature, the high-temperature closing device forcibly closes the valve plate in the open state, and the valve plate of the fire damper is always in the locked closed state, thus protecting the lives of the residents. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following is a more detailed description of the specific embodiments of the present invention in conjunction with the drawings:

[0016] Figure 1 is a schematic longitudinal sectional structure diagram of the present invention;

[0017] Figure 2 is Figure 1 a schematic right view structure diagram;

[0018] Figure 3 is a schematic structure diagram of the secondary locking mechanism of the high-temperature closing device of the present invention;

[0019] Figure 4 is a schematic structure diagram of an implementation state of the high-temperature closing device of the present invention;

[0020] Figure 5 is Figure 4 the A-A sectional structure diagram of;

[0021] Figure 6 is Figure 5 the state diagram when the valve plate pressing strip in is opened;

[0022] Figure 7 is a schematic structure diagram of another implementation state of the high-temperature closing device of the present invention;

[0023] Figure 8 is Figure 7 the B-B sectional structure diagram of;

[0024] Figure 9 is Figure 7 the schematic structure diagram of the locking pressure plate in;

[0025] Figure 10 is a schematic structure diagram of another embodiment;

[0026] Figure 11 is Figure 10 a schematic right view structure diagram;

[0027] Figure 12Schematic structural diagram of a flue system with a fire and backflow prevention valve. Detailed implementation mode

[0028] Referring to the attached drawings, the fire and backflow prevention valve with a locking mechanism includes a flue gas passage formed by a housing 1. The flue gas passage is cylindrical. One end of the flue gas passage has an air inlet 2, and the opposite end is the air outlet end. An end face 3 adapted to the flue gas passage is provided at the air outlet end. An air outlet 5 is provided on the end face 3. A rotatable valve plate 4 that can only open in the air outlet direction and corresponds to the air outlet 5 is provided on the end face 3. In this embodiment, referring to Figure 1 , Figure 2 , an installation disk is provided on the outer wall of the housing 1. The installation disk is integrally processed with the flue gas passage forming the air inlet 2. After being formed by stamping, the end face 3 is fixedly connected to the installation disk. Two air outlets 5 are provided on the end face of the air outlet end. A boss or groove facing the outer end face (this outer end face faces the air outlet direction of the flue gas passage) is provided around the periphery of the air outlet 5. Two rotatable valve plates 4 that can only open in the air outlet direction and correspond to the air outlets 5 are provided on the outer end face of the air outlet end. The two air outlets 5 are symmetrically arranged left and right on the end face of the air outlet end. The end face of the air outlet end and the upper ends of the two valve plates 4 are inclined towards the air inlet 2 direction. Bending edges or ridges corresponding to the aforementioned boss or groove are provided around the valve plate 4. A high-temperature closing device with a locking mechanism that can force the valve plate 4 to close towards the air inlet 2 side at a set temperature is provided on the end face 3, so that the valve plate 4 is always in a closed state. A secondary locking mechanism for the high-temperature closing device is provided at a set position of the fire and backflow prevention valve body 1 or the high-temperature closing device. A flow guide cover 20 in the same direction as the flue is provided at the air outlet end of the flue gas passage. The cross-section of the flow guide cover 20 is generally U-shaped. The provision of the flow guide cover 20 makes the flue gas discharge direction consistent with the flue direction, thus not affecting the smoothness of the common flue.

[0029] Referring to Figure 3 , the secondary locking mechanism for the high-temperature closing device includes a fixed cylinder 21 that can be installed at a set position of the fire and backflow prevention valve body 1 or the high-temperature closing device. One end of the fixed cylinder 21 is open, and this end is the installation end of the secondary locking mechanism for the high-temperature closing device. A compression spring 25 is provided at the inner end of the fixed cylinder 21. A locking pin 22 is sleeved on the compression spring 25. The outer end part of the locking pin 22 extends out of the open end of the fixed cylinder 21. The outer end of the locking pin 22 is in the shape of a tapered rod. The inner end of the locking pin 22 has an annular platform 23 adapted to the inner cavity shape of the fixed cylinder 21. A pin post 24 is provided at the inner end of the annular platform 23. The outer end of the compression spring 25 is sleeved on the pin post 24. The outer diameter of the annular platform 23 is larger than the outer diameter of the locking pin 22, and the outer diameter of the pin post 24 is smaller than the outer diameter of the annular platform 23. During installation, the outer end part of the locking pin 22 abuts against the operable locking component of the high-temperature closing device. When the secondary locking mechanism for the high-temperature closing device works, the outer end part of the locking pin 22 can press on the operable locking component of the high-temperature closing device.

[0030] See Figure 4 — Figure 6, A specific structure of a high-temperature shut-off device with a locking mechanism is as follows: It includes a bracket 6 installed on the outer end surface of the end face 3. A support shaft 7 is provided on the bracket 6. One end of the support shaft 7 has a threaded section. A notch is opened at one end of the support shaft 7 close to the valve plate 4. A valve plate pressing strip 14 is hinged in the notch through a hinge shaft 13. The valve plate pressing strip 14 consists of two branches symmetrically arranged along the support shaft 7. The two valve plate pressing strips 14 are respectively arranged corresponding to the two valve plates 4. A lock pressing disk 11 corresponding to the valve plate pressing strip 14 is sleeved on the support shaft 7. A pressing disk spring 9 is sleeved on the support shaft 7. A bimetallic strip 8 that can be separated at a set temperature and extends towards the lock pressing disk 11 is provided on the bracket 6. The bimetallic strip 8 is formed by welding two metal sheets with a welding material that can melt at a set temperature, or is made of a plug or a clamping device made of a hot-melt material that can melt at a set temperature. The bimetallic strip 8 can also be replaced by a hot-melt sheet that can melt at a set temperature. The lock pressing disk 11 is provided with a claw 16 that extends towards the bimetallic strip 8 and is clamped on the bimetallic strip 8. The bimetallic strip 8 is provided with a corresponding hole for the claw, or the bimetallic strip 8 is provided with a claw that extends towards the pressing strip lock pressing disk 11 and is clamped on the pressing strip lock pressing disk 11. The pressing strip lock pressing disk 11 is provided with a corresponding hole for the claw, so that a mutual locking relationship is formed between the pressing strip lock pressing disk 11 and the bimetallic strip 8. In this embodiment, a support shaft mounting hole is provided on the bracket 6. The bimetallic strip 8 is in the shape of a crank arm. One of the crank arms is provided with a mounting hole corresponding to the support shaft mounting hole on the bracket 6. The bimetallic strip 8 is sleeved on the support shaft 7. The support shaft 7 is fixed on the bracket 6 through a nut. Of course, the bimetallic strip 8 can be directly installed on the bracket 6. One end of the lock pressing disk 11 facing the pressing disk spring 9 is provided with a sunk groove 17. The valve plate pressing strip 14 is provided with a hook 15 that is buckled in the sunk groove 17. After the lock pressing disk 11 is separated from the bimetallic strip 8 and presses towards the valve plate pressing strip 14, a mutual locking mechanism is formed between the lock pressing disk 11 and the valve plate pressing strip 14. This mutual locking mechanism is that the valve plate pressing strip 14 is wedge-shaped at its hinged end after being opened. The lock pressing disk 11 and the corresponding end of the valve plate pressing strip 14 have a conical cavity 12. The valve plate pressing strip 14 with a wedge-shaped hinged end and the valve plate pressing strip 14 with a conical cavity 12 form a wedge-shaped lock. The valve plate pressing strip 14 is in the shape of a crank arm. The lock pressing disk 11 is generally in the shape of a cylinder. Outside the lock pressing disk 11 where the two valve plate pressing strips 14 are symmetrically arranged, when the two valve plate pressing strips 14 are in the locked state, the hook 15 provided on the valve plate pressing strip 14 (which is located on the relatively inner side of the valve plate pressing strip 14 at this time) is buckled in the sunk groove 17 of the lock pressing disk 11. One section of the crank arm of each of the two valve plate pressing strips 14 is respectively arranged axially parallel to the support shaft 7; when the two valve plate pressing strips 14 are opened, an included angle is formed between the relatively outer sides of the two valve plate pressing strips 14 at the hinged end, and the inner cone angle of the conical cavity 12 of the lock pressing disk 11 is consistent with the included angle formed by the two valve plate pressing strips 14. A wedge-shaped lock is formed between the inner conical surface of the conical cavity 12 of the lock pressing disk 11 and the relatively outer sides of the two valve plate pressing strips 14.When the flue gas temperature in the common flue reaches the set warning temperature, the solder between the bimetal strips 8 melts, and one of the strips detaches from the other. The locking pressure plate 11 is released from the restraint of the bimetal strips 8 and slides along the support shaft 7 under the action of the pressure plate compression spring 9. At this time, the hook 15 on the valve plate pressing strip 14 disengages from the sunk groove 17 of the locking pressure plate 11, and the locking pressure plate 11 presses against the two valve plate pressing strips 14, causing the two valve plate pressing strips 14 to open outward and press on the two valve plates 4. Since a wedge-shaped lock is formed between the valve plate pressing strip 14 and the locking pressure plate 11 with a conical cavity 12, the valve plate 4 remains in the closed state. An installation hole for the secondary locking mechanism of the high-temperature closing device is provided on the leg of the bracket 6, and the installation end of the secondary locking mechanism of the high-temperature closing device is installed corresponding to the installation hole. The outer end of the locking pin 22 of the secondary locking mechanism of the high-temperature closing device passes through the installation hole and extends towards the valve plate pressing strip 14 and abuts against the vertical crank arm of the valve plate pressing strip 14 ( Figure 5 as shown in the state). When the high-temperature closing device operates, that is, when the two valve plate pressing strips 14 open outward and press on the two valve plates 4, the outer end of the locking pin 22 can press on the upper part of the valve plate pressing strip 14 to perform secondary locking on the movable components of the high-temperature closing device. Figure 1 , Figure 4 For the fire prevention and backflow prevention valve with a locking mechanism shown, only one leg of the bracket 6 is provided with the secondary locking mechanism of the high-temperature closing device. In actual use, each leg can be provided with the secondary locking mechanism of the high-temperature closing device. Of course, the secondary locking mechanism of the high-temperature closing device can be installed on the fire prevention and backflow prevention valve body 1.

[0031] In the foregoing embodiment, the fire prevention and backflow prevention valve with a locking mechanism has an air outlet end face adapted to the flue gas passage. There are two air outlets on the end face, and rotatable valve plates corresponding to the air outlets and only opening in the air outlet direction are provided on the end face. The high-temperature closing device for forcibly closing the valve plates is Figure 4 the double-leg structure shown. In actual application, due to the diversity of the structure of the fire prevention and backflow prevention valve with a locking mechanism itself, for example: the valve plate is arranged in the flue gas passage of the fire prevention valve, the flue gas passage can also be a variable-diameter passage, the valve plate can be two pieces or one piece, and the opening direction of the valve plate can be opposed opening, side opening, upward opening, downward opening, etc. To adapt to the forced closing of the valve plates of the fire prevention and backflow prevention valves with a locking mechanism of different structures, the high-temperature closing device for forcibly closing the valve plates can also adopt a single-leg structure, that is, Figure 4Remove the left or right leg of the middle bracket 6 and only retain one leg, which is convenient for installing the high-temperature closing device at the corresponding position of the fire prevention check valve with a locking mechanism. For example, it can be installed on the end face of the air outlet through the foot folded outward at the end of the leg, or on the mounting plate of the fire prevention check valve with a locking mechanism, or on the side wall of the housing of the fire prevention check valve with a locking mechanism. The high-temperature closing device for forcibly closing the valve disc can be such that a support shaft 7 is provided on the bracket 6, a locking pressure disc 11 is sleeved on the support shaft 7, a pressure disc compression spring 9 is sleeved on the support shaft 7 between the locking pressure disc 11 and the bracket 6, a bimetallic strip 8 that extends towards the locking pressure disc 11 and can melt or separate at a set temperature is provided on the bracket 6, the locking pressure disc 11 is provided with a claw 16 that extends towards the bimetallic strip 8 and is clamped on the bimetallic strip 8, and a clamping hole corresponding to the claw 16 is provided on the bimetallic strip 8. When the flue gas temperature in the common flue reaches the set warning temperature, the solder between the bimetallic strips melts, and one of them falls off the other. The locking pressure disc 11 is released from the restraint of the bimetallic strip and slides along the support shaft 7 under the action of the pressure disc compression spring 9. The locking pressure disc 11 presses on the valve disc 4, and the valve disc 4 is in the closed state; at this time, as long as the outer diameter of the locking pressure disc 11 is adapted to the valve disc 4, it can be adapted to the fire prevention check valve with a locking mechanism of a single valve disc or a double valve disc; it can be a bracket with a single-leg structure or a bracket with a double-leg structure. Hinging a valve disc pressing strip 14 corresponding to the locking pressure disc 7 at one end of the support shaft 7 close to the valve disc 4 is a further optimization of the above structure. The valve disc pressing strip 14 can be two branches symmetrically arranged along the support shaft 7 for corresponding to the fire prevention valve that forcibly closes two valve discs, or it can be one branch for corresponding to the fire prevention valve that forcibly closes a single valve disc. A sink 17 is provided at one end of the locking pressure disc 11 facing the pressure disc compression spring 9, and a hook 15 that is buckled in the sink 17 is provided on the valve disc pressing strip 14. After the locking pressure disc 11 is released from the bimetallic strip 8 and presses towards the valve disc pressing strip 14, the valve disc pressing strip 14 opens outward and presses on the valve disc 4. Due to the wedge-shaped locking formed between the valve disc pressing strip 14 and the locking pressure disc 11 with a conical cavity 12, the valve disc 4 is always in the closed state.

[0032] See Figure 7 — Figure 9 Another specific structure of the high-temperature closing device with a locking mechanism is: including a bracket 6 installed on the outer end face of the end face 3, see Figure 7, the bracket 6 has a two-leg structure, or the left leg or the right leg of the bracket 6 can be removed, leaving only one leg. A support shaft 7 is provided on the bracket 6. One end of the support shaft 7 close to the valve plate 4 is hinged with a valve plate pressing strip 14. The valve plate pressing strip 14 is provided with two branches symmetrically arranged along the support shaft 7. The two valve plate pressing strips 14 are respectively arranged corresponding to the two valve plates 4. A locking pressure disc 11 corresponding to the valve plate pressing strip 14 is sleeved on the support shaft 7. A pressure disc compression spring 9 is sleeved on the support shaft 7. The bracket 6 is provided with a bimetallic strip 8 extending towards the locking pressure disc 11 and capable of separating at a set temperature. The bimetallic strip 8 can also be replaced by a hot melt sheet capable of melting at a set temperature. The locking pressure disc 11 is provided with a claw 16 extending towards the bimetallic strip 8 and clamped on the bimetallic strip 8. The bimetallic strip 8 is provided with a clamping hole corresponding to the claw 16, or the bimetallic strip 8 is provided with a claw extending towards the strip locking pressure disc 11 and clamped on the strip locking pressure disc 11. The strip locking pressure disc 11 is provided with a clamping hole corresponding to the claw, so that a mutual locking relationship is formed between the strip locking pressure disc 11 and the bimetallic strip 8. An inwardly arranged valve plate pressing strip guiding groove 19 is provided along the relatively outer side of the locking pressure disc 11. A clamping groove 18 is provided inside the valve plate pressing strip guiding groove 19. The valve plate pressing strip 14 is provided with a hook 15 clamped in the clamping groove 18. In this embodiment, the support shaft 7, the hinged structure of the valve plate pressing strip 14 on the support shaft 7, the structure of the bimetallic strip 8 and the installation structure of the bimetallic strip 8 are the same as those in the previous embodiment. The locking pressure disc 11 is generally in the shape of a strip plate. A hole sleeved with the support shaft 7 is provided in the middle part of the strip-shaped locking pressure disc 11. Inwardly arranged valve plate pressing strip guiding grooves 19 are provided at both ends along the length direction of the strip-shaped locking pressure disc 11. The relatively inner ends of the two valve plate pressing strip guiding grooves 19 are provided with clamping grooves 18. A claw 16 is provided on one side in the width direction of the strip-shaped locking pressure disc 11. Both ends in the length direction of the locking pressure disc 11 are bent towards the same side along the intersection of the valve plate pressing strip guiding groove 19 and the clamping groove 18. When the two valve plate pressing strips 14 are in the locked state, the hook 15 provided on the valve plate pressing strip 14 (which is located on the relatively inner side of the valve plate pressing strip 14 at this time) is clamped in the clamping groove 18 of the locking pressure disc 11. The two valve plate pressing strips 14 are respectively located in the guiding groove 19. The clamping groove 18 and the guiding groove 19 are separated by a partition strip. When the two valve plate pressing strips 14 are opened, the two valve plate pressing strips 14 are generally in a symmetrically parallel state. The outer edge of the partition strip between the clamping groove 18 and the guiding groove 19 is clamped in the hook 15, so that the two valve plate pressing strips 14 are in the locked state. When the flue gas temperature in the common flue reaches the set warning temperature, the solder between the bimetallic strips 8 melts, and one of them falls off the other. The locking pressure disc 11 is released from the restraint of the bimetallic strip 8 and slides along the support shaft 7 under the action of the pressure disc compression spring 9. At this time, the hook 15 on the valve plate pressing strip 14 forms a chute with the relatively inner side surface of the valve plate pressing strip 14 during the unfolding process of the valve plate pressing strip 14. The outer edge of the partition strip slides along this chute. The locking pressure disc 11 presses against the two valve plate pressing strips 14 and makes the two valve plate pressing strips 14 open outwards and press on the two valve plates 4. Since the valve plate pressing strip 14 is in the locked state, the valve plate 4 is always in the closed state.On the legs of the bracket 6, there are mounting holes for the secondary locking mechanism of the high-temperature shutdown device. The mounting end of the secondary locking mechanism of the high-temperature shutdown device is installed corresponding to the mounting holes. The outer end of the locking pin 22 of the secondary locking mechanism of the high-temperature shutdown device extends through the mounting holes towards the valve strip 14 and abuts against the valve strip 14 ( Figure 8 above the state locking pressure plate 11 shown). When the high-temperature shutdown device operates, that is, when the two valve strips 14 open outwards and press on the two valve plates 4, the outer end of the locking pin 22 can press on the upper part of the valve strip 14 to perform secondary locking on the movable components of the high-temperature shutdown device.

[0033] Figure 10 and Figure 11The fireproof check valve with a locking mechanism shown in the figure is a large-displacement diversion type fireproof check valve, which includes a flue gas passage composed of a housing 1. The flue gas passage is cylindrical. One end of the flue gas passage has an air inlet 2, and the opposite end is the air outlet end. An end face 3 adapted to the flue gas passage is provided at the air outlet end. An air outlet 5 is provided on the end face 3. A rotatable valve plate 4 corresponding to the air outlet 5 and only opening in the air outlet direction is provided on the end face 3. In this embodiment, a mounting plate is provided on the outer wall of the housing 1. The mounting plate is integrally formed with the flue gas passage forming the air inlet 2. The end face 3 is fixedly connected to the mounting plate after being stamped. Two air outlets 5 are provided on the end face of the air outlet end. Two rotatable valve plates 4 corresponding to the air outlets 5 and only opening in the air outlet direction are provided on the outer end face of the air outlet end. The two air outlets 5 are symmetrically arranged left and right on the end face of the air outlet end. The end face of the air outlet end and the upper ends of the two valve plates 4 are inclined towards the air inlet 2. The center line of the air inlet 2 forms an acute angle with the center line of the double air outlets 5. The air outlet area of the double air outlets 5 is larger than the area of the air inlet 2. A high-temperature closing device with a locking mechanism that can force the valve plate 4 to close towards the air inlet 2 side at a set temperature is provided on the end face 3 to keep the valve plate 4 in a closed state all the time. A secondary locking mechanism of the high-temperature closing device is provided at the set part of the high-temperature closing device. The high-temperature closing device with a locking mechanism includes a bracket 6 installed on the outer end face of the end face 3. The bracket 6 is located between the two valve plates 4. The bracket 6 is strip-shaped. The bracket 6 is installed on the outer end face of the end face 3 through two upper and lower legs. The outer side face of the bracket 6 is inclined downward from top to bottom towards the lower part of the end face 3, that is, the outer side face of the bracket 6 gradually approaches the right side face of the end face 3 from top to bottom. A chute 27 is opened in the lower section of the outer side face of the bracket 6. The chute 27 is arranged along the length direction of the outer side face of the bracket 6. A guide shaft 26 parallel to its outer side face is provided inside the bracket 6. Both ends of the guide shaft 26 are fixedly corresponding to the two upper and lower legs of the bracket 6. A spring 30 is sleeved on the guide shaft 26. An opening and closing slider 29 that extends into the inside of the bracket 6 and can slide along the chute 27 is provided on the outer side face of the bracket 6. The inner end of the opening and closing slider 29 is sleeved on the guide shaft 26. The upper rear part inside the opening and closing slider 29 contacts the spring 30. A fuse 28 that makes the opening and closing slider 29 compress the spring 30 upward is provided in the chute 27 below the opening and closing slider 29. When the temperature of the oil fume gas passage exceeds the fusing temperature of the fuse 28, the fuse 28 fuses. The opening and closing slider 29 slides down along the outer side face of the bracket 6 under the action of the spring 30 and gradually approaches the right end face of the end face 3. When the opening and closing slider 29 stops sliding, the opening and closing slider 29 just presses the two valve plates 4 to completely block the double air outlets 5 of the end face 3.

[0034] See Figure 12, A flue system with a fire and backflow prevention valve, comprising a common flue 31. A fire valve installation opening 32 is provided at a set position of the common flue. The fire valve installation opening 32 is generally provided on the wall surface of the common flue close to the side of the range hood. A fire and backflow prevention valve is installed in the fire valve installation opening 32. The installation disc of the fire and backflow prevention valve abuts against the wall surface of the common flue, and the air outlet of the fire and backflow prevention valve is located inside the common flue, and the air inlet of the fire and backflow prevention valve is located outside the common flue. The fire and backflow prevention valve can be installed and fixed in the fire valve installation opening 32 by any well-known method.

[0035] The specific structure of the above embodiment is for explaining the present invention rather than limiting the present invention. The inventive point of the present invention is directed to a fire and backflow prevention valve provided with a high-temperature closing device, and a secondary locking is performed on the movable components of the high-temperature closing device of the fire and backflow prevention valve to improve its safety. The secondary locking mechanism of the high-temperature closing device is provided at a set position of the fire and backflow prevention valve body or the high-temperature closing device. All improvements based on the present invention should fall within the protection scope of the present invention.

Claims

1. A fireproof check valve with a locking mechanism, comprising a fireproof check valve body (1). The fireproof check valve body (1) has a flue gas passage. One end of the flue gas passage has an air inlet (2), and the opposite end is the air outlet end. A rotatable valve plate (4) that can only open in the air outlet direction is provided in the flue gas passage or on the end face of the air outlet end. A high-temperature closing device with a locking mechanism is provided on the fireproof check valve body (1) that can force the valve plate (4) to close towards the air inlet side at a set temperature. The characteristics are A secondary locking mechanism for high-temperature closing is provided at the setting part of the fire prevention and backflow prevention valve body (1) or the high-temperature closing device; The secondary locking mechanism for high-temperature closing includes a fixed cylinder (21) that can be installed at the setting part of the fire prevention and backflow prevention valve body (1) or the high-temperature closing device. One end of the fixed cylinder (21) is open. A compression spring (25) is provided at the inner end of the fixed cylinder (21). A locking pin (22) is sleeved on the compression spring (25), and the outer end part of the locking pin (22) extends out of the open end of the fixed cylinder (21).

2. The fire prevention check valve with a locking mechanism according to claim 1, characterized in that The outer end of the locking pin (22) is in the shape of a tapered rod. The inner end of the locking pin (22) has a ring platform (23) adapted to the inner cavity shape of the fixed cylinder (21). A pin column (24) is provided at the inner end of the ring platform (23), and the outer end of the compression spring (25) is sleeved on the pin column (24).

3. The fire prevention check valve with a locking mechanism according to claim 1 or 2, characterized in that The high-temperature closing device with a locking mechanism includes a bracket (6) installed on the outer end face of the end face (3). A support shaft (7) is provided on the bracket (6). A lock pressure plate (11) is sleeved on the support shaft (7). A pressure plate compression spring (9) is sleeved on the support shaft (7). A heat-melting sheet or a separated bimetallic sheet (8) that can melt at a set temperature and extends towards the lock pressure plate (11) is provided on the bracket (6). The lock pressure plate (11) and the heat-melting sheet or the bimetallic sheet (8) are interlocked with each other.

4. The fire prevention check valve with a locking mechanism according to claim 3, characterized in that One end of the support shaft (7) close to the valve plate (4) is hinged with a valve plate pressing strip (14). The lock pressure plate (11) is arranged corresponding to the valve plate pressing strip (14). A sunk groove (17) is provided at one end of the lock pressure plate (11) facing the pressure plate compression spring (9). A hook (15) that is buckled in the sunk groove (17) is provided on the valve plate pressing strip (14). After the lock pressure plate (11) breaks away from the bimetallic sheet (8) and presses towards the valve plate pressing strip (14), a mutually locking mechanism is formed between the lock pressure plate (11) and the valve plate pressing strip (14).

5. The fire prevention check valve with a locking mechanism according to claim 4, characterized in that The mutually locking mechanism is that the valve plate pressing strip (14) is wedge-shaped at its hinged end after being opened. The corresponding end of the lock pressure plate (11) and the valve plate pressing strip (14) has a tapered cavity (12). The valve plate pressing strip (14) with a wedge-shaped hinged end and the valve plate pressing strip (14) with a tapered cavity (12) form a wedge-shaped lock.

6. The fire prevention check valve with a locking mechanism according to claim 1 or 2, characterized in that The high-temperature shut-off device with a locking mechanism includes a bracket (6) installed on the outer end face of the end face (3). A support shaft (7) is provided on the bracket (6). One end of the support shaft (7) close to the valve disc (4) is hinged with a valve disc pressing strip (14). A lock pressing disc (11) corresponding to the valve disc pressing strip (14) is sleeved on the support shaft (7). A pressing disc compression spring (9) is sleeved on the support shaft (7). A heat-melting sheet or a separated bimetallic sheet (8) that can melt at a set temperature and extends towards the lock pressing disc (11) is provided on the bracket (6). The lock pressing disc (11) and the bimetallic sheet (8) are interlocked. An inwardly arranged valve disc pressing strip guiding groove (19) is provided along the relative outer side of the lock pressing disc (11). A clamping groove (18) is provided inside the valve disc pressing strip guiding groove (19). A hook (15) that is buckled in the clamping groove (18) is provided on the valve disc pressing strip (14).

7. The fire prevention check valve with a locking mechanism according to claim 1 or 2, characterized in that The high-temperature shut-off device with a locking mechanism includes a bracket (6) installed on the outer end face of the end face (3). The outer side face of the bracket 6 inclines downward from top to bottom towards the lower part of the end face (3). A sliding groove (27) arranged along its length direction is opened in the lower section of the outer side face of the bracket (6). A guiding shaft (26) parallel to the outer side face is provided inside the bracket (6). A spring (30) is sleeved on the guiding shaft (26). An opening and closing sliding block (29) that extends into the inside of the bracket (6) and can slide along the sliding groove (27) is provided on the outer side face of the bracket (6). The inner end of the opening and closing sliding block (29) is sleeved on the guiding shaft (26). The rear part inside the opening and closing sliding block (29) contacts the spring (30) upwards. A fuse wire (28) that enables the opening and closing sliding block (29) to compress the spring (30) upwards is provided in the sliding groove (27) below the opening and closing sliding block (29). After the fuse wire (28) melts, the opening and closing sliding block (29) slides down along the outer side face of the bracket (6) under the action of the spring (30) and gradually approaches the right end face of the end face (3). When the opening and closing sliding block (29) stops sliding, the opening and closing sliding block (29) just presses tightly on the two valve discs (4) to completely block the double outlet (5) of the end face (3).

8. A flue system, characterized in that Comprising: A common flue, and a fire damper installation opening is provided at a set position of the common flue; The fire damper installation opening is internally installed with a fire prevention and backflow prevention valve as described in any one of claims 1 - 7.

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