A herringbone gear pump and method of using same

Abstract

The application provides a herringbone gear pump and a use method thereof. The herringbone gear pump comprises a herringbone gear pump body, a filter device is fixedly installed at a liquid inlet of the herringbone gear pump body, the filter device comprises a filter box, a filter plate is slidably installed in the filter box, a vertical seat is fixedly installed on the inner wall of the bottom of the filter box, the bottom of the filter plate is in contact with the top of the vertical seat, an upper sealing plate is fixedly installed on the top of the filter plate, the upper sealing plate is fixedly connected with the filter box, a collecting box is slidably installed in the filter box, a lower sealing plate is fixedly installed on the bottom of the collecting box, and two groups of abutting mechanisms are arranged on the bottom of the filter box. The herringbone gear pump has the advantages that impurities in liquid can be filtered, the filtered impurities can be collected, the operation amount of impurity cleaning is small, and the herringbone gear pump does not need to be stopped during the impurity cleaning.

Description

Technical Field

[0001] This invention relates to the field of gear pump technology, and in particular to a herringbone gear pump and its method of use. Background Technology

[0002] Gear pumps are rotary pumps that transport or pressurize liquids by relying on the change and movement of the working volume formed between the pump cylinder and meshing gears. They consist of two gears, a pump body, and front and rear covers forming two enclosed spaces. When the gears rotate, the volume of the space on the disengaged side of the gears increases from small to large, creating a vacuum that draws in the liquid. The volume of the space on the meshing side of the gears decreases from large to small, forcing the liquid into the pipeline. Gear pumps can be roughly divided into three types according to their tooth shape: spur gear, helical gear, and herringbone gear. Among them, herringbone gears not only have the advantages of helical gears but also overcome the disadvantage of helical gears generating large axial forces. They also have advantages such as high efficiency and low noise, and have good energy-saving effects.

[0003] Gear pumps are commonly used as pumps for transferring asphalt, heavy fuel oil, heavy gear oil, and heavy diesel oil. These liquids often contain small amounts of impurities. However, existing herringbone gear pumps lack a pre-filtration function, which allows larger particles to enter between the gears. Over time, this causes the gears to wear too quickly, affecting the service life of the gear pump.

[0004] Therefore, it is necessary to provide a herringbone gear pump and its usage method to solve the above-mentioned technical problems. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a herringbone gear pump and its method of use that can filter impurities in liquids, collect the filtered impurities, reduce the amount of impurity cleaning operations, and eliminate the need to stop the pump during impurity cleaning.

[0006] To solve the above-mentioned technical problems, the present invention provides a herringbone gear pump, comprising: a herringbone gear pump body, a filter device fixedly installed at the inlet of the herringbone gear pump body, the filter device including a filter box, a filter plate slidably installed inside the filter box, a vertical seat fixedly installed on the bottom inner wall of the filter box, the bottom of the filter plate contacting the top of the vertical seat, an upper sealing plate fixedly installed on the top of the filter plate, the upper sealing plate being fixedly connected to the filter box, a collection box slidably installed inside the filter box, a lower sealing plate fixedly installed at the bottom of the collection box, and two sets of abutment mechanisms provided at the bottom of the filter box, the two sets of abutment mechanisms being used to abut and fix the lower sealing plate, so that the top of the lower sealing plate is tightly fitted with the bottom of the filter box.

[0007] Preferably, each set of the abutment mechanisms includes a fixed shaft, a circular sleeve, a mounting block, a rotating arm, an abutment plate, and a first threaded rod. The fixed shaft is fixedly installed at the bottom of the filter box, the circular sleeve is rotatably sleeved on the fixed shaft, the mounting block is integrally formed at the bottom of the circular sleeve, the rotating arm is fixedly installed on one side of the outer wall of the mounting block, the abutment plate is slidably installed on the rotating arm, and the first threaded rod is threadedly installed on the rotating arm, with the top end of the first threaded rod rotatably connected to the abutment plate.

[0008] Furthermore, an anti-slip pad is fixedly installed on the top of the contact plate.

[0009] Furthermore, the top of the filter box is provided with an upper sealing groove, and a first sealing gasket is fixedly installed in the upper sealing groove. The bottom of the upper sealing plate is integrally formed with a first sealing protrusion, the bottom of the first sealing protrusion extends into the upper sealing groove and contacts the first sealing gasket.

[0010] Furthermore, a lower sealing groove is provided at the bottom of the filter box, and a second sealing gasket is fixedly installed in the lower sealing groove. A second sealing protrusion is integrally formed on the top of the lower sealing plate, and the top of the second sealing protrusion extends into the lower sealing groove and contacts the second sealing gasket.

[0011] Furthermore, side grooves are provided on both inner walls of the filter box, and the same partition plate is slidably installed in the two side grooves. The partition plate is located above the collection box, and the end of the partition plate near the filter plate is in contact with the vertical base. A rectangular cavity is provided inside the filter box, and a connecting plate is slidably installed in the rectangular cavity. A rectangular sliding opening is provided on the inner wall of the rectangular cavity near the vertical base, and the partition plate passes through the rectangular sliding opening and is slidably connected to the inner wall of the rectangular sliding opening. The end of the partition plate away from the vertical base is fixedly connected to the connecting plate. A second threaded rod is threadedly installed on the inner wall of the rectangular cavity away from the vertical base. One end of the second threaded rod is rotatably connected to the connecting plate, and the other end of the second threaded rod extends to the outside of the filter box.

[0012] Preferably, the partition plate has an arc-shaped contact edge at one end near the filter plate, and the vertical base has an arc-shaped groove that matches the arc-shaped contact edge.

[0013] To solve the above-mentioned technical problems, the present invention also provides a method for using a herringbone gear pump, comprising the following steps:

[0014] T: The filter device is fixedly installed at the inlet of the herringbone gear pump body, the liquid input pipe is fixedly connected to the inlet of the filter device, and the herringbone gear pump body is connected to the motor.

[0015] T: The liquid to be transported is introduced into the filter device, and the motor is started to drive the herringbone gear pump body to run;

[0016] T: Periodically release the contact mechanism on the filter device from the lower sealing plate, and remove the collection box to clean impurities;

[0017] T: Reassemble the collection box after cleaning the impurities, and re-secure the lower sealing plate by using the abutment mechanism.

[0018] Preferably, before performing operation T, the second threaded rod on the filter device is rotated until the partition plate contacts the vertical seat.

[0019] Compared with related technologies, the herringbone gear pump and its usage method provided by the present invention have the following beneficial effects:

[0020] ① The herringbone gear pump provided by this invention, through the setting of a filtration device, specifically including components such as a filter box, filter plate, collection box, lower sealing plate, and upper sealing plate, can filter impurities in the liquid, preventing impurities from entering the herringbone gear pump body and damaging the herringbone gear, and can also collect the filtered impurities in a concentrated manner; through the setting of the abutment mechanism, the user can easily disassemble or fix the collection box quickly, facilitating the periodic cleaning of impurities;

[0021] ② The herringbone gear pump provided by this invention, through the setting of structures such as partition plate, rectangular cavity, second threaded rod, and rectangular sliding port, allows the partition plate to move into the filter box when it is necessary to clean impurities in the collection box. When removing and reinstalling the collection box, the partition plate can be moved into the filter box by rotating the second threaded rod, thus blocking the insertion port of the collection box and preventing liquid from flowing out from the bottom of the filter box. In this case, it is not necessary to stop the machine, which has the advantage of ensuring normal liquid delivery.

[0022] ③ The method of using the herringbone gear pump provided by the present invention can filter out impurities in the liquid by using a filter device. By performing simple operations on the second threaded rod and the abutment mechanism, the abutment fixing of the collection box can be released, so that the collection box can be taken out for impurity cleaning. The overall operation is minimal, easy to master, and does not require stopping the machine in the middle. Attached Figure Description

[0023] Figure 1 A three-dimensional structural schematic diagram of the first embodiment of the herringbone gear pump provided by the present invention;

[0024] Figure 2 for Figure 1 A cross-sectional three-dimensional structural schematic diagram of the filter device shown;

[0025] Figure 3for Figure 2 A three-dimensional structural diagram of the resisting mechanism shown;

[0026] Figure 4 for Figure 2 A schematic diagram of the three-dimensional structure of the collection box shown;

[0027] Figure 5 for Figure 1 A top-view three-dimensional structural diagram of the filter box shown.

[0028] Figure 6 for Figure 1 A three-dimensional structural diagram of the filter box shown from a bottom-view perspective;

[0029] Figure 7 This is a partial cross-sectional three-dimensional structural schematic diagram of the second embodiment of the herringbone gear pump provided by the present invention;

[0030] Figure 8 for Figure 7 An enlarged structural diagram of part A shown;

[0031] Figure 9 for Figure 7 A schematic diagram of the cross-sectional structure of the filter box shown;

[0032] Figure 10 for Figure 8 The diagram shows a three-dimensional structure of the partition plate.

[0033] The following are the labeling elements in the diagram: 1. Herringbone gear pump body; 2. Filter box; 3. Filter plate; 4. Vertical seat; 5. Upper sealing plate; 6. Lower sealing plate; 7. Collection box; 8. Abutment mechanism; 801. Fixed shaft; 802. Circular sleeve; 803. Mounting block; 804. Rotating arm; 805. First limiting slide rod; 806. Abutment plate; 807. First threaded rod; 9. Upper sealing groove; 10. Lower sealing groove; 11. Side sliding groove; 12. Divider plate; 13. Rectangular cavity; 14. Connecting plate; 15. Second threaded rod; 16. Second limiting slide rod; 17. Rectangular sliding opening; 18. Arc groove. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] First Embodiment

[0036] Please refer to the following: Figures 1-6In the first embodiment of the present invention, the herringbone gear pump includes: a herringbone gear pump body 1, which adopts the conventional design of herringbone gear pumps in the prior art. A filter device is fixedly installed at the liquid inlet of the herringbone gear pump body 1. The filter device includes a filter box 2. The top of the filter box 2 has an elongated opening, and a filter plate 3 is slidably installed inside the elongated opening. The filter plate 3 is used to intercept and filter impurities in the liquid to be transported. A vertical seat 4 is fixedly installed on the bottom inner wall of the filter box 2, and a rubber strip is fixedly installed on the top of the vertical seat 4. The bottom of the filter plate 3 abuts against the rubber strip on the top of the vertical seat 4. The rubber strip deforms after being abutted, increasing the contact area with the filter plate 3, so that there are no gaps between them, ensuring the filtration effect. To prevent liquid from leaking from the top of the filter box 2, an upper sealing plate 5 is fixedly installed on the top of the filter plate 3. The upper sealing plate 5 is fixedly connected to the filter box 2 by screws. To further improve the sealing effect, the top of the filter box 2... The filter box 2 has an upper sealing groove 9, in which a first sealing gasket is fixedly installed. The bottom of the upper sealing plate 5 is integrally formed with a first sealing protrusion, the bottom of which extends into the upper sealing groove 9 and contacts the first sealing gasket. The bottom inner wall of the filter box 2 has a collection box insertion port, in which a collection box 7 is slidably installed. The bottom of the collection box 7 is fixedly installed with a lower sealing plate 6, which is used to seal the collection box insertion port to prevent liquid from leaking out from the bottom of the filter box 2. The bottom of the filter box 2 has two sets of abutting mechanisms 8, which are used to abut and fix the lower sealing plate 6, so that the top of the lower sealing plate 6 is tightly fitted with the bottom of the filter box 2. In order to improve the sealing effect, the bottom of the filter box 2 has a lower sealing groove 10, in which a second sealing gasket is fixedly installed. The top of the lower sealing plate 6 is integrally formed with a second sealing protrusion, the top of which extends into the lower sealing groove 10 and contacts the second sealing gasket.

[0037] In this embodiment, to improve the ease of fixing the lower sealing plate 6 while not hindering the removal of the collection box 7, each set of abutment mechanisms 8 includes a fixed shaft 801, a circular sleeve 802, a mounting block 803, a rotating arm 804, an abutment plate 806, and a first threaded rod 807. The fixed shaft 801 is fixedly installed at the bottom of the filter box 2, the circular sleeve 802 is rotatably sleeved on the fixed shaft 801, the mounting block 803 is integrally formed at the bottom of the circular sleeve 802, the rotating arm 804 is fixedly installed on one side outer wall of the mounting block 803, the abutment plate 806 is slidably installed on the rotating arm 804, and the first threaded rod 807 is threadedly installed on the rotating arm 804. The top end of the first threaded rod 807 is rotatably connected to the abutment plate 806. To limit the position of the abutment plate 806, a sliding mounting is also installed through and slidably on the rotating arm 804. There are two first limiting slide rods 805, which are located on both sides of the first threaded rod 807, and their top ends are fixedly connected to the abutment plate 806. When the lower sealing plate 6 is fixed by abutment, the abutment plate 806 is rotated to be directly below the lower sealing plate 6, and then the first threaded rod 807 is rotated to drive the abutment plate 806 to rise until the abutment plate 806 forms a tight abutment with the lower sealing plate 6. When it is necessary to remove the collection box 7, the first threaded rod 807 is rotated counterclockwise to separate the abutment plate 806 from the lower sealing plate 6, and then the abutment plate 806 is rotated about 180°. In this way, the abutment mechanism 8 will not obstruct the downward movement of the lower sealing plate 6, and the collection box 7 can be removed smoothly. The top of the abutment plate 806 is fixedly installed with an anti-slip pad to prevent the abutment plate 806 from slipping and improve the fixing effect.

[0038] In this embodiment:

[0039] When in use, connect the inlet of the filter box 2 to the outlet of the liquid input pipe, and connect the input shaft of the herringbone gear pump body 1 to the output shaft of the motor. Before the liquid enters the herringbone gear pump body 1, it needs to pass through the filter plate 3. Larger particles of impurities in the liquid will be intercepted by the filter plate 3. The intercepted impurities will fall into the collection box 7 under the action of gravity. Since the liquid is filtered in advance, the herringbone gears in the herringbone gear pump body 1 will not be damaged by prolonged engagement with impurities.

[0040] When cleaning impurities from collection box 7, with liquid delivery stopped, sequentially rotate the first threaded rod 807 of the two contact mechanisms 8 counterclockwise. During this counterclockwise rotation, the first threaded rod 807 moves downwards, causing the contact plate 806 to move downwards, moving it away from the lower sealing plate 6. Then, rotate the lower sealing plate 6 approximately 180°, so that the contact plate 806 is no longer directly below it. Hold the handle at the bottom of the lower sealing plate 6 and pull downwards to remove collection box 7 from filter box 2. Then, the impurities in the collection box 7 can be cleaned. After cleaning, the collection box 7 is reinserted into the filter box 2, ensuring that the second sealing protrusion enters the lower sealing groove 10. Then, the lower sealing plate 6 is pushed upward so that its top is in contact with the bottom of the filter box 2. After that, both abutment plates 806 are rotated to be directly below the lower sealing plate 6 and aligned. Finally, the two first threaded rods 807 are rotated clockwise in sequence so that the two abutment plates 806 are in close contact with the lower sealing plate 6. This completes the work of re-abutting and fixing the collection box 7.

[0041] Compared with related technologies, the herringbone gear pump provided by the present invention has the following beneficial effects:

[0042] The herringbone gear pump provided by this invention, through the setting of a filtration device, specifically including a filter box 2, a filter plate 3, a collection box 7, a lower sealing plate 6, an upper sealing plate 5, etc., can filter impurities in the liquid, preventing impurities from entering the herringbone gear pump body 1 and damaging the herringbone gears, and can also collect the filtered impurities in a concentrated manner; through the setting of the abutment mechanism 8, the user can easily and quickly disassemble or fix the collection box 7, facilitating the periodic cleaning of impurities.

[0043] Second embodiment:

[0044] Based on the herringbone gear pump provided in the first embodiment of this application, the second embodiment of this application proposes another herringbone gear pump. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0045] The second embodiment of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0046] Please refer to the following: Figure 7-10The herringbone gear pump also includes two side grooves 11 respectively opened on the inner walls of the two sides of the filter box 2. The same partition plate 12 is slidably installed in the two side grooves 11. The partition plate 12 is located above the collection box 7. The end of the partition plate 12 near the filter plate 3 contacts the vertical seat 4. In order to increase the contact area, the end of the partition plate 12 near the filter plate 3 is provided with an arc-shaped contact edge. The vertical seat 4 is provided with an arc-shaped groove 18 adapted to the arc-shaped contact edge. The arc-shaped contact edge fits against the inner wall of the arc-shaped groove 18. A rectangular cavity 13 is opened in the filter box 2. A connecting plate 14 is slidably installed in the rectangular cavity 13. Specifically, two second limiting slide rods 16 are slidably installed on the inner wall of the rectangular cavity 13 away from the vertical seat 4. The ends of the limiting slide rods 16 near the vertical seat 4 are fixedly connected to the connecting plate 14, and the two second limiting slide rods 16 are located on both sides of the second threaded rod 15 mentioned below. A rectangular sliding opening 17 is provided on the inner wall of the rectangular cavity 13 near the vertical seat 4. The size of the rectangular sliding opening 17 is adapted to the partition plate 12. The partition plate 12 passes through the rectangular sliding opening 17 and is slidably connected to the inner wall of the rectangular sliding opening 17. The end of the partition plate 12 away from the vertical seat 4 is fixedly connected to the connecting plate 14. An internal threaded hole is provided on the inner wall of the rectangular cavity 13 away from the vertical seat 4. The second threaded rod 15 is installed in the internal thread of the internal threaded hole. One end of the second threaded rod 15 is rotatably connected to the connecting plate 14, and the other end of the second threaded rod 15 extends to the outside of the filter box 2.

[0047] In this embodiment:

[0048] In the initial state, the separator 12 is mostly located inside the rectangular cavity 13, and will not block the collection box 7, so that the impurities intercepted by the filter plate 3 can fall into the collection box 7.

[0049] When it is necessary to clean the impurities in the collection box 7, first rotate the second threaded rod 15 clockwise. As the second threaded rod 15 rotates clockwise, it gradually moves into the rectangular cavity 13. Through the connecting plate 14, it pushes the partition plate 12 to slide towards the vertical seat 4. As the second threaded rod 15 rotates, the end of the partition plate 12 with the arc-shaped contact edge will eventually enter the arc-shaped groove 18 of the vertical seat 4 and form a tight fit with the inner wall of the arc-shaped groove 18. In this way, the partition plate 12 blocks the insertion port of the collection box, so that the liquid will not flow downward. Therefore, when the collection box 7 is removed or reinstalled, it is not necessary to stop the machine to ensure the normal delivery of liquid. During this process, the impurities that are intercepted will fall on the partition plate 12.

[0050] After reinstalling the collection box 7, rotate the second threaded rod 15 counterclockwise to reset the separator plate 12. During the reset process, the outer edge of the rectangular sliding mouth 17 scrapes the separator plate 12, causing impurities on the separator plate 12 to fall into the collection box 7. Impurities intercepted by the filter plate 3 can also fall back into the collection box 7.

[0051] Third embodiment:

[0052] This embodiment provides a method for using a herringbone gear pump, specifically including the following steps:

[0053] T1: The filter device is fixedly installed at the liquid inlet of the herringbone gear pump body 1, the liquid input pipe is fixedly connected to the liquid inlet of the filter device, and the herringbone gear pump body 1 is connected to the motor.

[0054] T2: Introduce the liquid to be transported into the filter device and start the motor to drive the herringbone gear pump body 1 to run;

[0055] T3: Every once in a while, first rotate the second threaded rod 15 on the filter device until the partition plate 12 abuts against the vertical seat 4, then release the abutment mechanism 8 on the filter device from the lower sealing plate 6, and take out the collection box 7 to clean the impurities.

[0056] T4: Reassemble the collection box 7 after cleaning the impurities, and re-attach and fix the lower sealing plate 6 by the contact mechanism 8. Then rotate the second threaded rod 15 to reset the partition plate 12.

[0057] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A herringbone gear pump comprising a herringbone gear pump body (1), characterized in that, The inlet of the herringbone gear pump body (1) is fixedly provided with a filter device, the filter device comprises a filter box (2), a filter plate (3) is slidably arranged in the filter box (2), a vertical seat (4) is fixedly arranged on the inner wall of the bottom of the filter box (2), the bottom of the filter plate (3) is in contact with the top of the vertical seat (4), an upper sealing plate (5) is fixedly arranged on the top of the filter plate (3), the upper sealing plate (5) is fixedly connected with the filter box (2), a collecting box (7) is slidably arranged in the filter box (2), a lower sealing plate (6) is fixedly arranged on the bottom of the collecting box (7), the bottom of the filter box (2) is provided with two groups of abutting mechanisms (8), the two groups of abutting mechanisms (8) are used for abutting and fixing the lower sealing plate (6), so that the top of the lower sealing plate (6) is tightly attached to the bottom of the filter box (2); Any one of the abutting mechanisms (8) comprises a fixed shaft (801), a round sleeve (802), a mounting block (803), a rotating arm (804), an abutting plate (806) and a first threaded rod (807), the fixed shaft (801) is fixedly arranged on the bottom of the filter box (2), the round sleeve (802) is rotatably arranged on the fixed shaft (801), the mounting block (803) is integrally arranged on the bottom of the round sleeve (802), the rotating arm (804) is fixedly arranged on one side of the mounting block (803), the abutting plate (806) is slidably arranged on the rotating arm (804), and the first threaded rod (807) is threadedly arranged on the rotating arm (804), and the top end of the first threaded rod (807) is rotatably connected with the abutting plate (806). The top of the abutting plate (806) is fixedly provided with an anti-skid pad.

2. The herringbone gear pump of claim 1, wherein, The top of the filter box (2) is provided with an upper sealing groove (9), a first sealing pad is fixedly arranged in the upper sealing groove (9), and a first sealing protrusion is integrally arranged on the bottom of the upper sealing plate (5), the bottom of the first sealing protrusion extends into the upper sealing groove (9) and is in contact with the first sealing pad.

3. The herringbone gear pump of claim 1, wherein, The bottom of the filter box (2) is provided with a lower sealing groove (10), a second sealing pad is fixedly arranged in the lower sealing groove (10), and a second sealing protrusion is integrally arranged on the top of the lower sealing plate (6), the top of the second sealing protrusion extends into the lower sealing groove (10) and is in contact with the second sealing pad.

4. The herringbone gear pump of claim 1, wherein, Two side edges of the filter box (2) are provided with side edge sliding grooves (11), and the same partition plate (12) is slidingly installed in the two side edge sliding grooves (11), the partition plate (12) is located above the collecting box (7), one end of the partition plate (12) close to the filter plate (3) is in contact with the vertical seat (4), a rectangular cavity (13) is formed in the filter box (2), the connecting plate (14) is slidingly installed in the rectangular cavity (13), a rectangular sliding opening (17) is formed in the inner wall of one side of the rectangular cavity (13) close to the vertical seat (4), the partition plate (12) penetrates through the rectangular sliding opening (17) and is in sliding connection with the inner wall of the rectangular sliding opening (17), one end of the partition plate (12) away from the vertical seat (4) is fixedly connected with the connecting plate (14), the second threaded rod (15) is threadedly installed on the inner wall of one side of the rectangular cavity (13) away from the vertical seat (4), one end of the second threaded rod (15) is rotatably connected with the connecting plate (14), and the other end of the second threaded rod (15) extends out of the filter box (2).

5. The herringbone gear pump of claim 4, wherein, One end of the partition plate (12) close to the filter plate (3) is provided with an arc surface abutting edge, and the vertical seat (4) is provided with an arc-shaped groove (18) matched with the arc surface abutting edge.

6. A method of using a herringbone gear pump, characterized in that, The method comprises the following steps: T1: fixing and installing the filter device at the liquid inlet of the double helical gear pump body (1), fixing the liquid inlet pipe of the filter device to the liquid inlet of the filter device, and connecting the double helical gear pump body (1) to the motor; T2: introducing the liquid to be transported into the filter device, and starting the motor to drive the double helical gear pump body (1) to run; T3: periodically releasing the abutting and fixing of the abutting mechanism (8) on the filter device to the lower sealing plate (6), taking out the collecting box (7) to clean the impurities; T4: reassembling the collecting box (7) after the impurities are cleaned, and abutting and fixing the lower sealing plate (6) through the abutting mechanism (8).

7. The method of using the herringbone gear pump of claim 6, wherein, Before the operation of T3, the second threaded rod (15) on the filter device is rotated until the partition plate (12) abuts against the vertical seat (4).

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