CN216895808U - Fire-proof valve - Google Patents
Fire-proof valve Download PDFInfo
- Publication number
- CN216895808U CN216895808U CN202123393373.4U CN202123393373U CN216895808U CN 216895808 U CN216895808 U CN 216895808U CN 202123393373 U CN202123393373 U CN 202123393373U CN 216895808 U CN216895808 U CN 216895808U
- Authority
- CN
- China
- Prior art keywords
- valve body
- connecting rod
- fire
- rotating shaft
- driving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000007789 sealing Methods 0.000 claims abstract description 3
- 239000000428 dust Substances 0.000 claims description 2
- 230000007306 turnover Effects 0.000 claims 1
- 230000002265 prevention Effects 0.000 abstract description 11
- 239000000779 smoke Substances 0.000 description 6
- 238000005457 optimization Methods 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 238000004378 air conditioning Methods 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 238000009423 ventilation Methods 0.000 description 1
Images
Landscapes
- Safety Valves (AREA)
- Fluid-Driven Valves (AREA)
Abstract
A fire prevention valve comprises a cylindrical fire prevention valve body with two open ends, a valve plate unit, a driving device and an emergency valve closing heavy hammer. The valve plate unit comprises a plurality of turning plates and a plurality of fixing plates, the turning plates are distributed in the fireproof valve body in parallel at intervals, and a plurality of rotating shafts which are used for being rotatably connected with the side wall of the fireproof valve body are arranged on the turning plates; the fixed plate is fixed in the inner cavity of the fireproof valve body and is used for sealing and attaching a plurality of turning plates when the fixed plate is closed so as to close the fireproof valve body. The driving device comprises an air cylinder arranged on one side of the fireproof valve body, and a crank connecting rod mechanism for driving a plurality of turning plates to synchronously rotate is arranged between the air cylinder and the rotating shaft. The emergency valve closing heavy hammer is arranged on the other side of the fireproof valve body, and a counterweight connecting rod for driving the heavy hammer to drive the plurality of turning plates to rotate is arranged between the emergency valve closing heavy hammer and one of the rotating shafts. The utility model can carry out normal opening and closing work when the fire damper loses electric signal control, does not need manual participation, and saves manual labor time and cost.
Description
Technical Field
The utility model relates to the technical field of fire fighting equipment, in particular to a fire damper.
Background
Fire safety equipment such as a fire damper is required to be installed in a factory for safety production of enterprises. Fire dampers are commonly installed in factories on the ductwork of ventilation or air conditioning systems. In the fire damper in the prior art, a cylinder is connected with a temperature sensing or smoke sensing electric signal, the temperature sensing or smoke sensing electric signal controls the cylinder, and the opening and closing of the valve are realized through the movement of a piston rod on the cylinder. However, the prior art has some problems:
fire prevention valve among the prior art is connected with temperature sensing or smoke sensing signal of telecommunication, and under the condition of conflagration breaing out, the signal of telecommunication probably causes the damage, and the cylinder stop motion of being connected with temperature sensing or smoke sensing signal of telecommunication, the valve by cylinder control can not open and close after the cylinder stop motion, makes fire prevention valve can not carry out normal work.
The fire damper in the prior art can not normally open and close and needs a worker to manually open and close after working, and the installation position of the fire damper is special, so that the fire damper can not be opened and closed quickly in emergency, and smoke can not be blocked quickly. The fire-proof valve needs to be opened and closed manually, so that the labor cost and the labor intensity are increased.
The fire damper in the prior art is mostly rectangular, and the rectangular fire damper can be installed on a pipeline only by a round connecting piece when being installed, so that the complexity of equipment and the production cost are increased.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a fire damper which can be opened and closed normally when the fire damper loses electric signal control, does not need manual participation and saves manual labor time and cost.
In order to solve the technical problems, the utility model adopts a specific scheme that the fire damper comprises: the emergency valve closing device comprises a cylindrical fire valve body with two open ends, a valve plate unit arranged in the fire valve body, a driving device arranged on the fire valve body and an emergency valve closing heavy hammer;
the valve plate unit comprises a plurality of turning plates and a plurality of fixing plates, the turning plates are distributed in the fireproof valve body in parallel at intervals, and a plurality of rotating shafts which are used for being rotatably connected with the side wall of the fireproof valve body are arranged on the turning plates; the fixed plate is fixed in the inner cavity of the fireproof valve body and is in sealing fit with the plurality of turning plates when the fixed plate is closed so as to close the fireproof valve body;
the driving device comprises an air cylinder arranged on one side of the fireproof valve body, and a crank connecting rod mechanism for driving a piston rod of the air cylinder to drive the turning plates to synchronously rotate is arranged between the air cylinder and the rotating shaft;
the emergency valve closing heavy hammer is arranged on the other side of the fireproof valve body, and a counterweight connecting rod for driving the heavy hammer to drive the plurality of turning plates to rotate is arranged between the emergency valve closing heavy hammer and one of the rotating shafts.
As a further optimization of a fire damper of the present invention: and a dust cover is arranged on one side of the fire-proof valve body, which is provided with the cylinder.
As a further optimization of a fire damper of the present invention: the number of the turning plates is three, and the turning plates comprise an upper turning plate, a middle turning plate and a lower turning plate.
As a further optimization of a fire damper of the present invention: the crank connecting rod mechanism comprises a driving connecting rod fixedly arranged on a rotating shaft of the lower turning plate, the driving connecting rod is V-shaped, one end of the driving connecting rod is hinged with a piston rod of the air cylinder, and the other end of the driving connecting rod is hinged with an integrated connecting rod; and a rotating shaft connecting rod is arranged on the rotating shaft on the upper turning plate and the middle turning plate and is hinged with the integrated connecting rod.
As a further optimization of a fire damper of the present invention: the emergency valve closing heavy hammer is fixedly connected with the rotating shaft on the middle turning plate.
Advantageous effects
The utility model relates to a fire prevention valve which comprises a fire prevention valve body, a valve plate unit arranged on the fire prevention valve body and an emergency valve closing heavy hammer. Be equipped with the valve plate in the fire prevention valve body, be equipped with drive arrangement and emergent valve closing weight on the both sides of fire prevention valve body respectively. The cylinder is connected with the electromagnetic valve, and the electromagnetic valve controls the cylinder so as to control the opening and closing of the valve plate. Under special conditions, when the fire damper cannot be opened or closed when the cylinder stops operating, the fire damper is closed by using the emergency valve closing weight as a spare valve closing part.
The fire-proof valve body has the advantages that the two ends of the fire-proof valve body are in the shape of the open cylinder, the structure of the cylindrical fire-proof valve body is simple, and the fire-proof valve body can be directly connected with a pipeline without an additional connecting piece when being installed. The device is convenient, trouble-saving, production cost-saving and space-saving during installation.
According to the emergency valve closing heavy hammer arranged on one side of the fireproof valve body, when an electric signal which can be connected with an air cylinder by the emergency valve closing heavy hammer breaks down, the valve plate is driven to rotate to close by falling of the emergency valve closing heavy hammer, manual opening and closing are not needed, and labor cost, time and energy are saved.
The fixed plate in the fire-proof valve body can ensure that the turning plate is completely sealed when being closed, thereby preventing smoke from leaking and keeping the environment clean.
Drawings
FIG. 1 is a schematic front view of the present invention;
FIG. 2 is a schematic perspective view of the driving device in an open state according to the present invention;
FIG. 3 is a schematic perspective view of an emergency valve closing weight according to the present invention in an open state;
FIG. 4 is a schematic perspective view of the driving device in a closed state according to the present invention;
FIG. 5 is a schematic perspective view of an emergency valve closing weight according to the present invention in a closed state;
FIG. 6 is a schematic structural diagram of a driving device according to the present invention;
FIG. 7 is a schematic diagram of an emergency valve closing weight according to the present invention;
the attached drawings are marked as follows: 1. the valve comprises a support, 2, a mounting seat, 3, a rotating seat, 4, a cylinder, 5, a crank-link mechanism, 501, a rotating shaft connecting rod, 502, a rotating shaft pin shaft, 503, a driving connecting rod, 504, a bushing, 505, an integrated connecting rod, 506, a locker, 507, a driving pin shaft, 6, a valve plate unit, 601, a lower rotating shaft, 602, a lower turning plate, 603, an upper rotating shaft, 604, an upper turning plate, 605, a middle turning plate, 606, a middle rotating shaft, 607, a fixing plate, 7, a counterweight connecting rod, 8, an emergency valve closing weight, 9, a fastening bolt, 10, a flange, 11, a fireproof valve body, 12, a connecting frame, 13 and a copper sleeve.
Detailed Description
As shown in fig. 2, the fire damper of the present invention includes a fire damper body 11, a valve plate unit 6 disposed in the fire damper body 11, and a driving device and an emergency valve closing weight 8 disposed on the fire damper body 11.
As shown in fig. 1, the fire-proof valve body 11 is in the shape of a cylinder with two open ends, the open ends of the front and rear ends of the fire-proof valve body 11 are provided with flanges 10 for being fixedly connected with a pipeline, and the flanges 10 are uniformly provided with round holes for bolts to pass through. The fire prevention valve body 11 bilateral symmetry between the flange 10 is equipped with the support 1 that is used for installing drive arrangement and emergent valve closing weight 8 respectively, is equipped with the bolt hole that is used for fixing support 1 on fire prevention valve body 11 on support 1, and the bolt hole fit installs fastening bolt 9. The driving device is arranged on a left bracket 1 of the fireproof valve body 11, and a dustproof cover is arranged on the left bracket 1. The emergency valve closing weight 8 is arranged on the bracket 1 on the right side of the fireproof valve body 11.
As shown in fig. 1, the valve plate unit 6 is disposed in an inner cavity of the fire-proof valve body 11, and the valve plate unit 6 includes three turning plates disposed in the fire-proof valve body 11 at parallel intervals and three rotating shafts disposed on the three turning plates for rotationally and hermetically connecting the three turning plates with a side wall of the fire-proof valve body 11. The three turning plates are an upper turning plate 604, a middle turning plate 605 and a lower turning plate 602 respectively, the middle turning plate 605 is horizontally arranged along the central position of the fire-proof valve body 11, the upper turning plate 604 and the lower turning plate 602 are respectively positioned at the upper side and the lower side of the middle turning plate 605, and the upper turning plate 604 and the lower turning plate 602 are symmetrically arranged.
As shown in fig. 2, the upper turning plate 604 and the lower turning plate 602 have the same shape, both the left and right sides of the upper turning plate 604 and the lower turning plate 602 are cylindrical arcs attached to the fire-proof valve body 11, one side of the upper turning plate 604 and the lower turning plate 602 is arc-shaped attached to the cylindrical fire-proof valve body 11, and the other side is linear. The fire valve 11 below the linear side of the upper and lower flaps 604, 602 is provided with a fixing plate 607. The fixing plate 607 is fixedly arranged on the inner wall of the fire-proof valve body 11, the fixing plate 607 is attached and sealed with the fire-proof valve body 11 when the upper turning plate 604 and the lower turning plate 602 are closed, and the shape of the fixing plate 607 is the shape of a gap between the linear side of the upper turning plate 604 and the lower turning plate 602 and the fire-proof valve body 11. As shown in fig. 4, the upper and lower sides of the middle flap 605 are linear and aligned with the linear sides of the upper flap 604 and the lower flap 602 and the fixing plate 607.
As shown in fig. 1, the rotating shaft on the upper turning plate 604 is an upper rotating shaft 603, the rotating shaft on the lower turning plate 602 is a lower rotating shaft 601, and the rotating shaft on the middle turning plate 605 is a middle rotating shaft 606. The upper rotating shafts 603 are respectively located at two ends of the upper turning plate 604 and rotatably connected with the fire-proof valve body 11, the middle rotating shafts 606 are located at two ends of the middle turning plate 605 and rotatably connected with the fire-proof valve body 11, and the lower rotating shafts 601 are respectively located at two ends of the lower turning plate 602 and rotatably connected with the fire-proof valve body 11. As shown in fig. 4, the joints of the upper rotating shaft 603, the middle rotating shaft 606, and the lower rotating shaft 601 with the fire-proof valve body 11 are provided with copper sleeves 13.
As shown in fig. 6, the driving device includes a cylinder 4 disposed on the left bracket 1 of the fire-proof valve body 11, a piston rod of the cylinder 4 is disposed downward, a mounting seat 2 for mounting the cylinder 4 is disposed at a joint of the cylinder 4 and the bracket 1, and a rotary seat 3 for the cylinder 4 to rotate is disposed on the mounting seat 2. The right side of the cylinder 4 on the support 1 of the fire-proof valve body 11 is provided with a crank connecting rod mechanism 5, and the crank connecting rod mechanism 5 drives the turning plate to rotate synchronously by a piston rod of the cylinder 4.
As shown in fig. 4, the crank link mechanism 5 includes a driving link 503 fixedly disposed on the lower rotating shaft 601, and a bushing 504 is disposed at a connection position of the driving link 503 and the lower rotating shaft 601. The driving connecting rod 503 is V-shaped, and one end of the driving connecting rod 503 facing the cylinder 4 is hinged to a piston rod of the cylinder 4, and moves up and down under the driving of the piston rod on the cylinder 4. The other end of the driving connecting rod 503 is provided with a driving pin 507, the driving connecting rod 503 is hinged and connected with an integrated connecting rod 505 shown in fig. 2, the integrated connecting rod 505 is a long plate parallel to the air cylinder 4, and the length of the integrated connecting rod 505 is the distance from the upper rotating shaft 603 to the lower rotating shaft 601. As shown in fig. 4, a rotating shaft connecting rod 501 is disposed between the upper rotating shaft 603 and the middle rotating shaft 606 and the integrated connecting rod 505, and the integrated connecting rod 505 drives the upper rotating shaft 603 and the middle rotating shaft 606 to rotate together, and a rotating shaft pin 502 is disposed at a connection between the rotating shaft connecting rod 501 and the integrated connecting rod 505. Stainless steel washers are arranged at the joints of the upper rotating shaft 603 and the middle rotating shaft 606 and the rotating shaft connecting rod 501, and the lockers 506 in fig. 2 are arranged on the stainless steel washers at the joints of the upper rotating shaft 603 and the middle rotating shaft 606 and the rotating shaft connecting rod 501.
As shown in fig. 5, the emergency weight is used for the cylinder 4 to fall down to drive the turning plate to close when the cylinder stops operating, the emergency valve closing weight 8 is arranged on the bracket 1 on the right side of the fire-proof valve body 11, the emergency valve closing weight 8 is fixedly connected with the middle rotating shaft 606, the middle rotating shaft 606 is provided with a connecting frame 12, a counterweight connecting rod 7 for the emergency valve closing weight 8 to drive the middle turning plate 605 to rotate is arranged between the middle rotating shaft 606 penetrating through the connecting frame 12 and the emergency valve closing weight 8, and a bolt for fixedly connecting the counterweight connecting rod 7 and the emergency valve closing weight 8 is arranged at the connection position.
The specific embodiment of the utility model is as follows: when the cylinder 4 works normally, the opening and closing state in the fireproof valve body 11 is controlled by the cylinder 4. The fire damper is in an open state under a normal state, and the cylinder is divided into the following two stages during normal operation:
the first stage is as follows: when the piston rod on the cylinder 4 moves upwards, one end of the driving connecting rod 503 hinged with the piston rod rises, the right end hinged with the integrated connecting rod 505 drives the integrated connecting rod 505 to move downwards, and at this time, the lower rotating shaft 601 fixedly connected with the driving connecting rod 503 rotates clockwise, so that the lower turning plate 602 rotates clockwise by 90 degrees to be in a closed state. Meanwhile, the rotating shaft connecting rod 501 hinged to the integrated connecting rod 505 is driven by the integrated connecting rod 505 to perform clockwise circular motion, so as to drive the upper rotating shaft 603 and the middle rotating shaft 606 to rotate clockwise, and then the upper turning plate 604 and the middle turning plate 605 rotate clockwise by 90 degrees to be in a closed state, as shown in fig. 4.
And a second stage: when the piston rod of the cylinder 4 moves upwards, one end of the driving connecting rod 503 hinged with the piston rod descends, the right end hinged with the integrated connecting rod 505 drives the integrated connecting rod 505 to move upwards, and at this time, the lower rotating shaft 601 fixedly connected with the driving connecting rod 503 rotates anticlockwise, so that the lower turning plate 602 rotates anticlockwise by 90 degrees to be in an opening state. Meanwhile, the rotating shaft connecting rod 501 hinged to the integrated connecting rod 505 is driven by the integrated connecting rod 505 to perform counterclockwise circular motion, so as to drive the upper rotating shaft 603 and the middle rotating shaft 606 to rotate counterclockwise, and the upper turning plate 604 and the middle turning plate 605 rotate counterclockwise by 90 degrees to be in an open state, as shown in fig. 1, fig. 2 and fig. 3.
After the power is cut off, the cylinder 4 stops moving, the emergency valve closing heavy hammer 8 on the support 1 on the right side of the fireproof valve body 11 falls anticlockwise under the action of the gravity, the falling is carried out, the middle turning shaft 606 is driven to rotate anticlockwise through the counterweight connecting rod 7, and the middle turning plate 605 is driven by the middle turning shaft 606 to rotate anticlockwise for 90 degrees and is in a closed state. The rotating shaft connecting rod 501 drives the integrated connecting rod 505 to descend through the rotation of the middle rotating shaft 606, so that the upper turning plate 604 and the lower turning plate 602 also rotate 90 degrees counterclockwise, and the fire damper under the damage of the cylinder 4 is in a closed state, as shown in fig. 5.
When the electric signal connected with the air cylinder 4 is normally electrified, the air cylinder 4 starts to normally operate, and the emergency valve closing heavy hammer 8 is driven by the piston rod of the air cylinder 4 to ascend, so that the fire damper is in an opening state.
Claims (5)
1. A fire damper, characterized in that: comprises a cylindrical fire-proof valve body (11) with two open ends, a valve plate unit (6) arranged in the fire-proof valve body (11), a driving device arranged on the fire-proof valve body (11) and an emergency valve closing heavy hammer (8);
the valve plate unit (6) comprises a plurality of turning plates and a plurality of fixing plates (607), the turning plates are distributed in the fireproof valve body (11) in parallel at intervals, and a plurality of rotating shafts which are used for being rotatably connected with the side wall of the fireproof valve body (11) are arranged on the turning plates; the fixing plate (607) is fixed in the inner cavity of the fire-proof valve body (11) and is used for sealing and attaching a plurality of turning plates when the fire-proof valve body (11) is closed so as to close the fire-proof valve body (11);
the driving device comprises an air cylinder (4) arranged on one side of the fireproof valve body (11), and a crank connecting rod mechanism (5) for driving a plurality of turning plates to synchronously rotate by a piston rod of the air cylinder (4) is arranged between the air cylinder (4) and the rotating shaft;
an emergency valve closing heavy hammer (8) is arranged on the other side of the fireproof valve body (11), and a counterweight connecting rod (7) for driving the heavy hammer (8) to drive the turnover plates to rotate is arranged between the emergency valve closing heavy hammer (8) and one of the rotating shafts.
2. A fire damper as claimed in claim 1, wherein: a dust cover is arranged on one side of the fire-proof valve body (11) provided with the cylinder (4).
3. A fire damper as claimed in claim 1, wherein: the number of the turning plates is three, and the turning plates comprise an upper turning plate (604), a middle turning plate (605) and a lower turning plate (602).
4. A fire damper as claimed in claim 3, wherein: the crank connecting rod mechanism (5) comprises a driving connecting rod (503) fixedly arranged on a rotating shaft of the lower turning plate (602), the driving connecting rod (503) is V-shaped, one end of the driving connecting rod (503) is hinged with a piston rod of the air cylinder (4), and the other end of the driving connecting rod (503) is hinged with an integrated connecting rod (505); a rotating shaft connecting rod (501) is arranged on a rotating shaft on the upper turning plate (604) and the middle turning plate (605), and the rotating shaft connecting rod (501) is hinged with the integrated connecting rod (505).
5. A fire damper as claimed in claim 3, wherein: the emergency valve closing heavy hammer (8) is fixedly connected with a rotating shaft on the middle turning plate (605).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202123393373.4U CN216895808U (en) | 2021-12-30 | 2021-12-30 | Fire-proof valve |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202123393373.4U CN216895808U (en) | 2021-12-30 | 2021-12-30 | Fire-proof valve |
Publications (1)
Publication Number | Publication Date |
---|---|
CN216895808U true CN216895808U (en) | 2022-07-05 |
Family
ID=82211967
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202123393373.4U Expired - Fee Related CN216895808U (en) | 2021-12-30 | 2021-12-30 | Fire-proof valve |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN216895808U (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115388184A (en) * | 2022-10-28 | 2022-11-25 | 自贡新比隆阀门有限公司 | High-performance double-plate ball valve |
-
2021
- 2021-12-30 CN CN202123393373.4U patent/CN216895808U/en not_active Expired - Fee Related
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115388184A (en) * | 2022-10-28 | 2022-11-25 | 自贡新比隆阀门有限公司 | High-performance double-plate ball valve |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN216895808U (en) | Fire-proof valve | |
US6361430B2 (en) | Balanced ventilation doors | |
CN210221486U (en) | Reliability test device of fire prevention blast gate | |
CN116104384A (en) | Marine pneumatic remote control shutter device | |
KR102047329B1 (en) | Fire extinguisher and exhaust vent device | |
CN108625750B (en) | Full-automatic door opening and closing device for monitoring fireproof door | |
CN211371388U (en) | Fireproof check valve with butterfly-shaped fireproof temperature sensing device | |
CN218669111U (en) | Be used for hanging current fire door that prevents of robot | |
CN211371377U (en) | Butterfly-shaped fireproof temperature sensing device | |
CN212429106U (en) | Safe and stable's hanging hole door reaches wind-powered electricity generation cabin cover including this hanging hole door | |
CN210264360U (en) | Pneumatic automatic door | |
CN213393578U (en) | Electromagnetic control fire-proof valve | |
CN208236190U (en) | A kind of vacuum drying oven firedoor hinge device | |
CA2348348C (en) | Balanced ventilation doors | |
GB2098475A (en) | Damper blade actuating mechanism | |
CN220451722U (en) | Shutter door | |
CN219413659U (en) | Automatic fire prevention valve structure | |
CN110701347A (en) | Butterfly-shaped fireproof temperature sensing device | |
CN216974639U (en) | Automatic fireproof door | |
CN212716719U (en) | Reverse partition device for adjusting air window | |
CN218818205U (en) | A firebreak device for rolling exhaust pipe break-make | |
CN221591894U (en) | Explosion-proof actuating mechanism of fire damper discharges fume | |
CN214743605U (en) | Smoke-proof and fire-proof regulating valve actuator | |
CN214789123U (en) | Electric gate valve | |
CN210920274U (en) | Fire-proof valve for ventilation system matched with combustion engine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
GR01 | Patent grant | ||
GR01 | Patent grant | ||
CF01 | Termination of patent right due to non-payment of annual fee | ||
CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220705 |