A closed seeding system for a crystallization kettle

Abstract

The application discloses a closed seed adding system for a crystallization kettle, which comprises a crystallization kettle, a crystallization adding tank and a centrifugal pump, the top end of the crystallization kettle is provided with a circulating inlet, the bottom end of the crystallization kettle is provided with a circulating outlet, the circulating outlet is connected with the liquid inlet of the centrifugal pump, the liquid outlet of the centrifugal pump is connected with the bottom end of the crystallization adding tank through a first pipeline, and the top end of the crystallization adding tank is connected with the circulating inlet through a second pipeline. The application adds an external circulation outside the crystallization kettle, under the condition that the valves on the circulating inlet and the circulating outlet are closed, the seed is added into the crystallization adding tank, then the centrifugal pump is started under the condition that the crystallization adding tank is isolated from the outside world, and the seed in the crystallization adding tank can be brought into the crystallization kettle from the liquid in the crystallization kettle through the external circulation, the seed is directly brought into the crystallization kettle through the external circulation, the balance and pressure in the crystallization kettle are not damaged, and the seed can be uniformly mixed during the circulation.

Description

Technical Field

[0001] This invention relates to the field of seed crystal addition technology in crystallization reactors, and more particularly to a closed seed crystal addition system for crystallization reactors. Background Technology

[0002] Introducing seed crystals in the early stages of precipitation crystallization to induce nucleation or inhibit primary nucleation is an effective method of crystallization. It facilitates the precipitation of crystals or precipitates from the solution. Seed crystals are typically small crystals of the precipitated material that can be forced into predetermined positions to form larger crystals.

[0003] When a solution is supersaturated, the dispersion or repulsion between molecules is less than the attraction between molecules, facilitating the formation of precipitates or crystals. Crystallization is a phase transition process, where substances form crystals from a gaseous, liquid, or solid phase under specific physical and chemical conditions. Forming crystals from a gaseous or liquid phase is initially difficult; the Gibbs function of atoms or molecules in the gaseous or liquid phase is very high, requiring a significant reduction in molecular entropy to form the crystal embryo—the crystal nucleus. Adding pre-made crystal nuclei facilitates the crystallization process and ensures that the crystals growing from the nuclei are uniform, thereby improving crystal yield and quality. Seed crystals play a crucial role in crystal growth.

[0004] The existing method of adding seed crystals to the crystallization vessel is to add the seed crystals directly above the crystallization vessel. When adding the seed crystals, the crystallization vessel is in an open state, and the inside of the crystallization vessel is directly exposed to the air. This will disrupt the constant pressure that needs to be maintained in the vessel and change the temperature conditions of the solution, thus breaking the equilibrium formed by the solution and affecting the crystallization effect. Summary of the Invention

[0005] To address the problems mentioned in the background section, the present invention provides a closed seeding system for a crystallization reactor.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A closed seed crystal addition system for a crystallization vessel includes a crystallization vessel, a crystallization addition tank, and a centrifugal pump. The top of the crystallization vessel is provided with a circulation inlet, and the bottom of the crystallization vessel is provided with a circulation outlet. The circulation outlet is connected to the inlet of the centrifugal pump. The outlet of the centrifugal pump is connected to the bottom of the crystallization addition tank through a first conduit, and the top of the crystallization addition tank is connected to the circulation inlet through a second conduit.

[0008] The second conduit is movably fitted with a first connector at the end away from the circulation inlet, and a second connector is movably fitted at the end of the first conduit away from the centrifugal pump. The top and bottom of the crystallization addition tank are provided with a plug-in mechanism, which is used to match the first connector and the second connector.

[0009] A drive mechanism is installed on the crystallization addition tank. The drive mechanism is used to drive the first connector and the second connector to move up and down, thereby combining and separating with the crystallization addition tank.

[0010] Preferably, the driving mechanism includes a cylinder, which is fixed to the top of the crystallization addition tank, and the output shaft of the cylinder is fixed to the first connector. A transmission box is fixed on the crystallization addition tank, and two sliders are vertically slidably installed in the transmission box via a slide rail. A rack is fixed on the side of the sliders that are close to each other, and a first gear is provided between the two racks. The first gear meshes with both racks.

[0011] Preferably, each of the two sliders is fixed with a lifting connecting rod, the end of the lifting connecting rod away from the slider extends movably to the outside of the transmission box, and one of the lifting connecting rods is fixed to the first connector, and the other lifting connecting rod is fixed to the second connector.

[0012] Preferably, a rotary motor is fixed at the bottom of the crystallization addition tank, the output shaft of the rotary motor extends into the crystallization addition tank and is fixed with a mounting bracket, multiple crystallization storage tanks are fixed on the mounting bracket, and a seed crystal addition port is opened at the top of the crystallization addition tank.

[0013] Preferably, the top and bottom of the crystallization tank are respectively provided with an upper insertion interface and a lower insertion interface, the upper insertion interface being matched with the first insertion connector and the lower insertion interface being matched with the second insertion connector.

[0014] Preferably, the crystallization tank is equipped with a seed crystal crushing mechanism inside, and an automatic sealing mechanism is installed at the lower insertion interface position inside the crystallization tank.

[0015] Preferably, the automatic sealing mechanism includes two matching sealing blocks, which are movably installed on the inner wall of the bottom end of the crystallization tank via an elastic guiding mechanism.

[0016] Preferably, the bottom end of the sealing block is provided with a guide groove, and two arc-shaped guide rails are fixed on the inner wall of the bottom end of the crystallization tank. Guide blocks are slidably installed on the arc-shaped guide rails, and the two guide blocks are fixed to the two sealing blocks respectively. A spring for pushing the guide blocks to reset is installed on the arc-shaped guide rails.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] 1. An external circulation system is added to the crystallization vessel. With the valves on the circulation inlet and outlet closed, add seed crystals to the crystallization addition tank. Then, while ensuring that the crystallization addition tank is isolated from the outside environment, turn on the centrifugal pump. The seed crystals in the crystallization addition tank can be carried from the liquid in the crystallization vessel into the crystallization vessel through the external circulation. The external circulation directly carries the seed crystals into the crystallization vessel, which does not disrupt the balance and pressure in the crystallization vessel and can also mix the seed crystals evenly during the circulation.

[0019] 2. When the cylinder drives the first connector to move up and down, one of the racks will move along with it, which in turn drives the other rack to move in the opposite direction synchronously. This will drive the second connector to move in the opposite direction synchronously with the first connector, so that the first and second connectors can be engaged and separated from the crystallization addition tank synchronously through one cylinder.

[0020] 3. When the crystallization tank is moved to the position corresponding to the first and second connectors, the cylinder drives the first and second connectors to be inserted into the upper and lower interfaces on the crystallization tank, respectively, thus ensuring the airtightness of the external circulation. When the external circulation is started, the liquid will flow through the crystallization tank, thereby carrying the crystal seeds inside the crystallization tank into the crystallization vessel, thus achieving the purpose of adding crystal seeds in a sealed manner. Since there are multiple crystallization tanks, multiple crystallization tanks can be filled at one time and then used as needed, which improves the efficiency of adding crystal seeds and eliminates the need to frequently add crystal seeds into the crystallization tank, making it more convenient to use.

[0021] 4. By adding an automatic sealing mechanism, when the automatic sealing mechanism is closed, the spring force will push the two sealing blocks closer to each other, thereby sealing the lower insertion interface and preventing the seed crystals inside the crystallization tank from flowing out of the lower insertion interface. When the second insertion connector moves upward, the second insertion connector is inserted into the guide groove. The second insertion connector can push the two sealing blocks open, so that the two sealing blocks are separated, thereby completing the insertion.

[0022] 5. By adding a seed crystal crushing mechanism, when the crystallization tank moves with the mounting bracket, one of the second gears meshes with the gear ring, thereby driving one of the rotating shafts to rotate. Then, through the meshing of the two second gears, the other rotating shaft can be driven to rotate synchronously in the opposite direction. This allows the crushing blades to crush the seed crystals, breaking larger crystal nuclei into more smaller seed crystals, increasing the number of seed crystals, and enabling the seed crystals to be more widely distributed in the solution, thereby improving the crystallization efficiency. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is the front view of the present invention;

[0025] Figure 2 This is a perspective view of the present invention;

[0026] Figure 3 This is an enlarged cross-sectional view of the transmission box of the present invention;

[0027] Figure 4 This is a magnified cross-sectional view of the crystallization tank of the present invention.

[0028] Figure 5 This is a magnified cross-sectional view of the crystallization tank of the present invention from a main perspective.

[0029] Figure 6 This is a schematic diagram of the meshing relationship between the second gear and the ring gear of the present invention;

[0030] Figure 7 This is a three-dimensional enlarged cross-sectional view of the crystallization tank of the present invention;

[0031] Figure 8 This is a magnified cross-sectional view of the crystallization tank of the present invention from a main perspective;

[0032] Figure 9 for Figure 7 Enlarged detail image of position A;

[0033] Figure 10 This is an exploded view of the automatic sealing mechanism of the present invention;

[0034] In the diagram: 1. Crystallization vessel; 101. Stirring mechanism; 102. Cooling jacket; 103. Circulation inlet; 1031. Second conduit; 104. Circulation outlet; 2. Crystallization addition tank; 201. Cylinder; 202. Transmission box; 2021. Slider; 2022. Rack; 2023. First gear; 2024. Lifting connecting rod; 203. First connector; 204. Second connector; 205. Seed crystal addition port; 2 06. Rotary motor; 2061. Mounting bracket; 207. Crystallization tank; 2071. Upper insertion interface; 2072. Lower insertion interface; 2073. Rotating shaft; 2074. Crushing blade; 2075. Second gear; 208. Gear ring; 3. Automatic sealing mechanism; 301. Sealing block; 302. Arc-shaped guide rail; 303. Guide block; 304. Spring; 305. Guide groove; 4. Centrifugal pump; 401. First conduit. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Example 1

[0037] Reference Figure 1-10 A closed seed crystal addition system for a crystallization vessel includes a crystallization vessel 1, a crystallization addition tank 2, and a centrifugal pump 4. The top of the crystallization vessel 1 is provided with a circulation inlet 103, and the bottom of the crystallization vessel 1 is provided with a circulation outlet 104. The circulation outlet 104 is connected to the liquid inlet of the centrifugal pump 4. The liquid outlet of the centrifugal pump 4 is connected to the bottom of the crystallization addition tank 2 through a first conduit 401. The top of the crystallization addition tank 2 is connected to the circulation inlet 103 through a second conduit 1031. The crystallization addition tank 2 is equipped with a stirring mechanism 101 and a cooling jacket 102.

[0038] An external circulation system is added to the outside of the crystallization vessel 1. With the valves on the circulation inlet 103 and circulation outlet 104 closed, crystal seeds are added to the crystallization addition tank 2. Then, with the crystallization addition tank 2 isolated from the outside, the centrifugal pump 4 is turned on. The crystal seeds in the crystallization addition tank 2 are carried from the liquid in the crystallization vessel 1 into the crystallization vessel 1 through the external circulation. The crystal seeds are directly carried into the crystallization vessel 1 through the external circulation, which does not disrupt the balance and pressure in the crystallization vessel 1 and can also mix the crystal seeds evenly during the circulation.

[0039] The first connector 203 is movably sleeved at the end of the second conduit 103 away from the circulation inlet 103, and the second connector 204 is movably sleeved at the end of the first conduit 401 away from the centrifugal pump 4. The top and bottom ends of the crystallization addition tank 2 are provided with a plug-in mechanism, which is used to match the first connector 203 and the second connector 204.

[0040] By adding a first connector 203 and a second conduit 1031, and setting a sealing structure at the connection position between the second connector 204 and the first conduit 401, the connection position is guaranteed to remain airtight during relative movement.

[0041] Specifically, airtightness can be maintained by sealing the connection point inside a flexible, expandable sleeve.

[0042] A drive mechanism is installed on the crystallization addition tank 2. The drive mechanism is used to drive the first connector 203 and the second connector 204 to move up and down, thereby combining and separating from the crystallization addition tank 2.

[0043] The first connector 203 and the second connector 204 are provided with sealing gaskets, which can maintain airtightness when the first connector 203 and the second connector 204 are inserted into the insertion mechanism at the top and bottom of the crystallization addition tank 2.

[0044] Example 2

[0045] Reference Figure 1-10The difference between this embodiment and embodiment 1 is that the driving mechanism includes a cylinder 201, which is fixed to the top of the crystallization addition tank 2, and the output shaft of the cylinder 201 is fixed to the first connector 203. A transmission box 202 is fixed on the crystallization addition tank 2. Two sliders 2021 are vertically slidably installed in the transmission box 202 via a slide rail. A rack 2022 is fixed on the side of the sliders 2021 that are close to each other. A first gear 2023 is provided between the two racks 2022, and the first gear 2023 meshes with both racks 2022.

[0046] The cylinder 201 can drive the first connector 203 to move up and down. Through the meshing of the rack 2022 and the first gear 2023, when one rack 2022 moves upward, the other rack 2022 will move in the same direction.

[0047] Among them, a lifting connecting rod 2024 is fixed on each of the two sliders 2021. The end of the lifting connecting rod 2024 away from the slider 2021 extends movably to the outside of the transmission box 202. One of the lifting connecting rods 2024 is fixed to the first plug 203, and the other lifting connecting rod 2024 is fixed to the second plug 204.

[0048] When cylinder 201 drives the first connector 203 to move up and down, one rack 2022 will move along with it, thereby driving the other rack 2022 to move in the opposite direction synchronously. This will drive the second connector 204 to move in the opposite direction synchronously with the first connector 203. Thus, cylinder 201 can achieve the purpose of synchronously engaging and disengaging the first connector 203 and the second connector 204 with the crystallization addition tank 2.

[0049] Example 3

[0050] Reference Figure 1-10 The difference between this embodiment and embodiment 1 is that a rotary motor 206 is fixed at the bottom of the crystallization addition tank 2, the output shaft of the rotary motor 206 extends into the crystallization addition tank 2 and is fixed with a mounting bracket 2061, a plurality of crystallization storage tanks 207 are fixed on the mounting bracket 2061, and a seed crystal addition port 205 is opened at the top of the crystallization addition tank 2.

[0051] The rotating motor 206 can drive the mounting bracket 2061 to rotate, thereby sequentially moving each crystallization tank 207 to the position corresponding to the first connector 203 and the second connector 204, and also sequentially moving each crystallization tank 207 to the position corresponding to the seed crystal addition port 205. When the crystallization tank 207 corresponds to the seed crystal addition port 205, seed crystals can be added into the crystallization tank 207 through the seed crystal addition port 205.

[0052] The crystallization storage tank 207 is provided with an upper insertion interface 2071 and a lower insertion interface 2072 at its top and bottom, respectively. The upper insertion interface 2071 is matched with the first insertion connector 203, and the lower insertion interface 2072 is matched with the second insertion connector 204.

[0053] When the crystallization tank 207 moves to the position corresponding to the first connector 203 and the second connector 204, the cylinder 201 drives the first connector 203 and the second connector 204 to be inserted into the upper insertion interface 2071 and the lower insertion interface 2072 on the crystallization tank 207, respectively. This ensures the airtightness of the external circulation. When the external circulation is started, the liquid will flow through the crystallization tank 207, thereby bringing the crystal seeds inside the crystallization tank 207 into the crystallization vessel 1, thus achieving the purpose of adding crystal seeds in a sealed manner. Since there are multiple crystallization tanks 207, multiple crystallization tanks 207 can be filled at one time and then used as needed, which improves the efficiency of adding crystal seeds. There is no need to add crystal seeds into the crystallization addition tank 2 frequently, making it more convenient to use.

[0054] Example 4

[0055] Reference Figure 1-10 The difference between this embodiment and embodiment 3 is that a seed crystal crushing mechanism is installed inside the crystallization tank 207, and an automatic sealing mechanism 3 is installed inside the crystallization tank 207 at the lower insertion interface 2072.

[0056] The automatic sealing mechanism 3 includes two matching sealing blocks 301, which are movably installed on the bottom inner wall of the crystallization tank 207 via an elastic guiding mechanism.

[0057] Among them, the bottom end of the sealing block 301 is provided with a guide groove 305, and two arc-shaped guide rails 302 are fixed on the inner wall of the bottom end of the crystallization tank 207. Guide blocks 303 are slidably installed on the arc-shaped guide rails 302. The two guide blocks 303 are respectively fixed to the two sealing blocks 301, and springs 304 for pushing the guide blocks 303 to reset are installed on the arc-shaped guide rails 302.

[0058] By adding an automatic sealing mechanism 3, when the automatic sealing mechanism 3 is closed, the elastic force of the spring 304 will push the two sealing blocks 301 closer to each other, thereby sealing the lower insertion interface 2072, so that the seed crystals inside the crystallization tank 207 will not flow out from the lower insertion interface 2072. When the second insertion connector 204 moves upward, the second insertion connector 204 is inserted into the guide groove 305. The second insertion connector 204 can push the two sealing blocks 301 open, so that the two sealing blocks 301 are separated, thereby completing the insertion.

[0059] Example 5

[0060] Reference Figure 1-10The difference between this embodiment and embodiment 4 is that the seed crystal crushing mechanism includes two rotating shafts 2073 rotatably installed inside the crystallization tank 207. Crushing blades 2074 are installed on the outside of the rotating shafts 2073. The bottom end of the rotating shafts 2073 extends to the outside of the crystallization tank 207 and is fixed with a second gear 2075. The two second gears 2075 mesh with each other. A toothed ring 208 is fixed on the inner wall of the crystallization tank 207, and one of the second gears 2075 meshes with the toothed ring 208.

[0061] When the crystallization tank 207 moves with the mounting bracket 2061, one of the second gears 2075 meshes with the gear ring 208, thereby driving one of the rotating shafts 2073 to rotate. Then, through the meshing of the two second gears 2075, the other rotating shaft 2073 can be driven to rotate synchronously in the opposite direction. This allows the crystal seeds to be crushed by the crushing blade 2074, so that larger crystal nuclei are broken into more smaller crystal seeds, increasing the number of crystal seeds and allowing them to be more widely distributed in the solution, thereby improving the crystallization efficiency.

[0062] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0063] In this invention, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," "link," and "fix" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0064] The control method of this invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the art. Furthermore, since this invention is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail here.

[0065] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A closed seed crystal addition system for a crystallization reactor, comprising a crystallization reactor (1), a crystallization addition tank (2), and a centrifugal pump (4), characterized in that: The top of the crystallization vessel (1) is provided with a circulation inlet (103), and the bottom of the crystallization vessel (1) is provided with a circulation outlet (104). The circulation outlet (104) is connected to the inlet of the centrifugal pump (4). The outlet of the centrifugal pump (4) is connected to the bottom of the crystallization addition tank (2) through a first conduit (401). The top of the crystallization addition tank (2) is connected to the circulation inlet (103) through a second conduit (1031). The second conduit (1031) is movably fitted with a first plug (203) at one end away from the circulation inlet (103), and the first conduit (401) is movably fitted with a second plug (204) at one end away from the centrifugal pump (4). The top and bottom ends of the crystallization addition tank (2) are provided with plug-in mechanisms, which are used to match the first plug (203) and the second plug (204). A drive mechanism is installed on the crystallization addition tank (2). The drive mechanism is used to drive the first connector (203) and the second connector (204) to move up and down, so as to combine and separate from the crystallization addition tank (2). A rotary motor (206) is fixed at the bottom of the crystallization addition tank (2). The output shaft of the rotary motor (206) extends into the crystallization addition tank (2) and is fixed with a mounting bracket (2061). Multiple crystallization storage tanks (207) are fixed on the mounting bracket (2061). A seed crystal addition port (205) is opened at the top of the crystallization addition tank (2). The crystallization tank (207) is provided with an upper insertion interface (2071) and a lower insertion interface (2072) at its top and bottom respectively. The upper insertion interface (2071) is matched with the first insertion connector (203), and the lower insertion interface (2072) is matched with the second insertion connector (204). The crystallization tank (207) is equipped with a seed crystal crushing mechanism inside, and an automatic sealing mechanism (3) is installed inside the crystallization tank (207) at the lower insertion interface (2072). The seed crystal crushing mechanism includes two rotating shafts (2073) rotatably installed inside the crystallization tank (207). Crushing blades (2074) are installed on the outside of the rotating shafts (2073). The bottom end of the rotating shafts (2073) extends to the outside of the crystallization tank (207) and is fixed with a second gear (2075). The two second gears (2075) mesh with each other. A toothed ring (208) is fixed on the inner wall of the crystallization tank (207), and one of the second gears (2075) meshes with the toothed ring (208). When the crystallization tank (207) moves with the mounting bracket (2061), one of the second gears (2075) meshes with the gear ring (208), thereby driving one of the rotating shafts (2073) to rotate. Then, through the meshing of the two second gears (2075), the other rotating shaft (2073) can be driven to rotate synchronously in the opposite direction. This allows the crystal seeds to be crushed by the crushing blade (2074), so that larger crystal nuclei are crushed into more smaller crystal seeds, increasing the number of crystal seeds and allowing the crystal seeds to be more widely distributed in the solution, thereby improving the crystallization efficiency.

2. The closed seeding system for a crystallization reactor according to claim 1, characterized in that: The driving mechanism includes a cylinder (201), which is fixed at the top of the crystallization addition tank (2). The output shaft of the cylinder (201) is fixed to the first connector (203). A transmission box (202) is fixed on the crystallization addition tank (2). Two sliders (2021) are vertically slidably installed in the transmission box (202) via a slide rail. A rack (2022) is fixed on the side of the sliders (2021) that are close to each other. A first gear (2023) is provided between the two racks (2022). The first gear (2023) meshes with both racks (2022).

3. A closed seeding system for a crystallization reactor according to claim 2, characterized in that: Both sliders (2021) are fixed with lifting connecting rods (2024). The end of the lifting connecting rod (2024) away from the slider (2021) extends movably to the outside of the transmission box (202). One of the lifting connecting rods (2024) is fixed to the first connector (203), and the other lifting connecting rod (2024) is fixed to the second connector (204).

4. A closed seeding system for a crystallizing reactor according to claim 1, characterized in that: The automatic sealing mechanism (3) includes two matching sealing blocks (301), which are movably installed on the bottom inner wall of the crystallization tank (207) through an elastic guiding mechanism.

5. A closed seeding system for a crystallization reactor according to claim 4, characterized in that: The bottom end of the sealing block (301) is provided with a guide groove (305). Two arc-shaped guide rails (302) are fixed on the inner wall of the bottom end of the crystallization tank (207). A guide block (303) is slidably installed on the arc-shaped guide rail (302). The two guide blocks (303) are respectively fixed to the two sealing blocks (301), and a spring (304) for pushing the guide block (303) to reset is installed on the arc-shaped guide rail (302).

Images