Vacuum valve and its shutter

Abstract

The invention relates to a vacuum valve and a shutter thereof, the shutter being movably arranged in a hollow valve body of the vacuum valve. The shutter has a blocking portion, a surface of the blocking portion having at least one turbulence groove, wherein the shutter extends a time of gas flow through a flow channel of the hollow valve body by the turbulence groove to reduce a gas conductance value.

Description

Technical Field

[0001] This invention relates to a vacuum valve and its gate, and more particularly to a vacuum valve and its gate that can control the gas conduction value. Background Technology

[0002] In typical semiconductor manufacturing processes, a process chamber with a vacuum environment is often required, along with control vacuum valves, so that wafers can be processed without external contamination. Vacuum valves are often used between the process chamber and the vacuum pump, or located before the gas inlet of the process chamber, to form part of the gas transport system.

[0003] Semiconductor manufacturing processes are typically carried out at very low pressures (high vacuum), such as Torr or lower. Since gas flow is molecular flow, controlling the gas conduction within the flow channel is extremely important for process yield. Taking a pendulum valve as an example, the gate is moved between open, soft-closed, and hard-closed positions by an actuator.

[0004] Since the diameter of the gate's blocking part is usually larger than the valve port diameter of the hollow valve body of the pendulum valve (there is overlap), when the gate moves from the hard closed position to the soft closed position or from the soft closed position to the hard closed position, the air conduction value will increase as the space between the flange of the gate and the contact area increases, which is not conducive to air conduction value control. Summary of the Invention

[0005] In view of this, one of the objectives of the present invention is to provide a vacuum valve and its gate to solve the problems of conventional technology.

[0006] To achieve the aforementioned objectives, the present invention provides a vacuum valve, comprising: a hollow valve body having a flow channel and an abutment area surrounding the flow channel; and a gate movably disposed within the hollow valve body of the vacuum valve, the gate having a blocking portion that moves longitudinally along an axis of the flow channel between a hard-closed position and a soft-closed position, wherein an abutment area of ​​a surface of the blocking portion of the gate is in the hard-closed position. In the closed position, the gate abuts against one of the surfaces of the contact area of ​​the hollow valve body to seal the flow channel. The surface of the shielding portion of the gate has at least one turbulence groove. In the soft-closed position, the contact area of ​​the surface of the shielding portion of the gate is disengaged from the surface of the contact area of ​​the hollow valve body. The gate extends the time for a gas to pass through the flow channel by extending the time for a gas to flow through the surface of the shielding portion of the gate and through the flow channel by means of the turbulence groove located in the flow channel, thereby reducing the gas conductivity of the flow channel of the hollow valve body.

[0007] To achieve the aforementioned objective, the present invention further proposes a gate, which is movably disposed in the hollow valve body of a vacuum valve, characterized in that: the gate has a blocking portion, one surface of the blocking portion having at least one turbulence groove, wherein the gate extends the time for a gas to flow through the surface of the blocking portion of the gate and pass through the flow channel of the hollow valve body by means of the turbulence groove, thereby reducing the gas conductivity of the flow channel of the hollow valve body.

[0008] The turbulence groove of the gate is at least one annular groove, a plurality of concentric annular grooves, a left vortex groove, or a right vortex groove.

[0009] The turbulence groove of the gate is at least one annular groove with a continuous sidewall, a plurality of concentric annular grooves, a left vortex groove, or a right vortex groove.

[0010] The width of the top of the turbulence channel of the gate is greater than the width of the bottom of the channel, and the turbulence channel of the gate has an inclined sidewall.

[0011] The shielding part of the gate is a flat surface, and the turbulence groove is recessed on the shielding part of the gate.

[0012] In this case, the blocking portion of the gate further moves laterally between an open position and a soft-close position. In the open position, the blocking portion of the gate is partially located on one side of the flow channel to partially overlap the flow channel, or in the open position, the blocking portion of the gate is entirely located on one side of the flow channel.

[0013] The gate also has a connecting part that connects the blocking part and the actuating element, and the actuating element moves the blocking part of the gate longitudinally between the soft-closed position and the hard-closed position via the connecting part.

[0014] When the blocking portion of the gate moves longitudinally along the axis of the flow channel between the soft-close position and the hard-close position, the center of the turbulence groove of the gate overlaps with the axis of the flow channel.

[0015] The gate's shielding portion has a sealing ring on its contact area.

[0016] The surface of the gate is a flat flange outside the contact area.

[0017] As described above, the vacuum valve and its gate of the present invention have the following advantages compared with existing structures: 1. The gate of the present invention utilizes surface structure to increase gas travel and generate a turbulence effect, which can increase airflow time and thus reduce gas conductivity. 2. The gate of the present invention has turbulence grooves, which can generate turbulence to increase airflow time and thus reduce gas conductivity. 3. The gate of the present invention has turbulence grooves, which can control gas conductivity, thereby preventing problems caused by excessive changes in gas conductivity when the vacuum valve is pumping or depressurizing. 4. The gate of the present invention has turbulence grooves, which can increase the structural strength of the gate, making it less prone to deformation, and has a lower manufacturing cost.

[0018] To enable you to have a better understanding of the technical features and effects of this invention, preferred embodiments and detailed descriptions are provided below. Attached Figure Description

[0019] Figure 1 This is a top view of the vacuum valve of the present invention, wherein the gate is located in a soft-closed position or a hard-closed position.

[0020] Figure 2 This is a top view of the vacuum valve of the present invention, wherein the gate is in the open position (fully open).

[0021] Figure 3 This is a simplified cross-sectional schematic diagram of the vacuum valve of the present invention, wherein the blocking part of the gate is located in the hard-closed position.

[0022] Figure 4 This is a simplified cross-sectional schematic diagram of the vacuum valve of the present invention, wherein the blocking part of the gate is located in the soft-close position.

[0023] Figure 5 This is a simplified cross-sectional schematic diagram of the vacuum valve of the present invention, wherein the blocking part of the gate is in the open position (fully open).

[0024] Figure 6 This is a top view of the gate of the vacuum valve of the present invention, wherein the turbulence groove is a plurality of concentric annular grooves.

[0025] Figure 7 For the present invention along Figure 6 A schematic diagram of the cross-section of the gate obtained by the I-I' section line.

[0026] Figure 8 for Figure 6 A three-dimensional schematic diagram of the gate shown.

[0027] Figure 9 This is a top view of the gate of the vacuum valve of the present invention, wherein the turbulence groove is a right vortex groove.

[0028] Figure 10For the present invention along Figure 9 A schematic diagram of the cross-section of the gate obtained from section line II-II'.

[0029] Figure 11 for Figure 9 A three-dimensional schematic diagram of the gate shown.

[0030] 10: Vacuum valve

[0031] 20: Hollow valve body

[0032] 22: Flow channel

[0033] 23: Axis

[0034] 24: Arrival Area

[0035] 25a: Hard-close position

[0036] 25b: Soft-close position

[0037] 25c: Opening position

[0038] 27: Abutment plate

[0039] 28: Surface

[0040] 40: Gate

[0041] 42: Covering part

[0042] 43: Surface

[0043] 44: Arrival Area

[0044] 45: Joint

[0045] 46: Actuating element

[0046] 47: Sealing ring

[0047] 50: Flow channel

[0048] 52: Top of the trench

[0049] 53: Sidewall

[0050] 54: Bottom of the tank

[0051] I-I': Section line

[0052] II-II': Section Line Detailed Implementation

[0053] To facilitate understanding of the technical features, content, advantages, and effects of this invention, the invention is described in detail below with reference to accompanying drawings and embodiments. The drawings used are for illustrative and supplementary purposes only and may not represent the actual scale and precise configuration of the invention in practice. Therefore, the scale and configuration of the accompanying drawings should not be used to interpret or limit the scope of the invention in actual implementation. Furthermore, for ease of understanding, the same elements in the following embodiments are indicated by the same symbols.

[0054] Furthermore, unless otherwise specified, the terms used throughout this specification and the claims generally have their ordinary meaning in the context of the art, the disclosure, and the specific content. Certain terms used to describe the invention will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the invention.

[0055] The use of terms such as "first," "second," and "third" in this article does not specifically refer to order or sequence, nor is it intended to limit this work; it is merely to distinguish components or operations described using the same technical terminology.

[0056] Secondly, when this article uses terms such as "contains", "includes", "has", or "contains", these are all open-ended terms, meaning that they include but are not limited to.

[0057] Please see Figures 1 to 11 , Figures 1 to 5 This is a schematic diagram of the structure of the vacuum valve of the present invention. Figures 6 to 11 This is a schematic diagram of the gate structure of the vacuum valve of the present invention. The vacuum valve 10 of the present invention includes at least a hollow valve body 20 and a gate 40. The hollow valve body 20 of the vacuum valve 10 has a flow channel 22 and an abutment area 24, the abutment area 24 surrounding the flow channel 22. Taking a pendulum valve as an example, the abutment area 24 is an annular groove of the vacuum valve. The hollow valve body 20 is a hollow shell with a circular valve port. The flow channel 22 is located in this valve port, and the abutment area 24 is located in the hollow valve body 20 and surrounds the flow channel 22. The present invention, by reducing the gas conductivity C, can prevent problems caused by excessive changes in gas conductivity during vacuum valve pumping or depressurization, such as reduced process yield or damage to peripheral parts. According to the calculation formula of gas conductivity C, gas conductivity C is Q / (P1-P2), and the unit is mm. 3(Volume) / s (seconds), where Q is the gas flux and P1-P2 is the pressure difference between the two ends of the flow channel. To reduce the gas conductivity C, this invention increases the denominator in the formula for calculating C, thus decreasing the gas conductivity C. That is, regardless of whether the gas flux Q decreases, as long as this invention increases the denominator, the gas conductivity C can be reduced. Therefore, one feature of the technical means employed in this invention is that the gate 40 has a turbulence groove 50, thereby forming a gate with a turbulence structure. This gate 40 utilizes the turbulence structure to generate turbulence, making the airflow (molecular flow) uneven, which can increase the aforementioned second (s) value, thus reducing the gas conductivity C. The gate 40 with the turbulence structure of this invention can be applied to any vacuum valve that requires control of gas conductivity.

[0058] The turbulence groove 50 of the present invention is, for example, at least one annular groove or a plurality of concentric annular grooves (e.g. Figures 6 to 8 As shown), a left-hand vortex groove or a right-hand vortex groove (as shown). Figures 9 to 11 As shown), the width of the top 52 of the turbulence groove 50 is greater than the width of the bottom 54, and the turbulence groove 50 has an inclined sidewall 53, the inclination of which is, for example, but not limited to, 60 degrees, and preferably has a continuous sidewall, which can effectively increase the gas flow time. Furthermore, the turbulence groove 50 is, for example, recessed on the surface 43 of the blocking portion 42 of the gate 40, wherein the shape of the blocking portion 42 corresponds to the valve orifice, preferably is circular, and the diameter of the blocking portion 42 is preferably slightly larger than the diameter of the valve orifice. The surface 43 of the blocking portion 42 can be, for example, a flat surface, but is not limited to a flat surface; the surface 43 can also be, for example, a non-flat surface, such as an arc surface or a curved surface. Taking the turbulence groove 50 as an example of a concentric annular groove composed of two annular grooves, the diameter of the outer annular groove is, for example, about twice the diameter of the inner annular groove, and the center of the concentric annular groove is exactly equal to the center of the blocking portion 42. The diameter of the blocking portion 42 of the gate 40 is, for example, approximately 1.35 times the diameter of the outer annular groove. The depth of the turbulence groove 50 is, for example, approximately 3 / 5 of the thickness of the blocking portion 42 of the gate 40, the width of the groove bottom 54 is, for example, approximately equal to the groove depth, and the inclination of the inclined sidewall of the turbulence groove 50 is, for example, approximately 60 degrees. The volume of the turbulence groove 50 is proportional to the level of turbulence effect. Although the shape of the turbulence groove 50 is listed above, and although a symmetrical shape is preferred, any shape of the turbulence groove 50 is within the scope of protection of this invention as long as the turbulence groove 50 can increase the time for gas to flow through the flow channel 22 via the gate 40 (increasing the gas travel of the gate 40 in the air intake direction), thereby reducing the gas conductance value of the flow channel 22 of the hollow valve body 20.

[0059] The gate 40 of this invention is movably disposed within the hollow valve body 20 of the vacuum valve 10. The gate 40 has a blocking portion 42, which is driven by an actuating element 46 to move longitudinally between a hard closed position 25a and a soft closed position 25b, and / or laterally between a soft closed position 25b and an open position 25c. The aforementioned longitudinal movement refers to the change in distance between the blocking portion 42 and the surface 28 of the contact area 24 of the hollow valve body 20 when the blocking portion 42 moves. The aforementioned lateral movement can be a flip-type lateral movement or a horizontal lateral movement. A flip-type lateral movement means that the distance between the blocking portion 42 and the surface 28 of the contact area 24 of the hollow valve body 20 changes when the blocking portion 42 flips and moves, while a horizontal lateral movement means that the blocking portion 42 maintains a fixed distance from the surface 28 of the contact area 24 of the hollow valve body 20 when the blocking portion 42 moves.

[0060] In detail, taking vacuum valve 10 as an example, which is a pendulum valve (e.g.) Figure 1 As shown), the gate 40 further includes, for example, a connecting portion 45 that connects the blocking portion 42 and the actuating element 46 respectively. The connecting portion 45 is, for example, a plate with a connecting hole (such as...). Figure 6 As shown), the actuating element 46 can actuate the blocking portion 42 of the gate 40 via the engaging portion 45 of the gate 40, thereby causing the blocking portion 42 to move longitudinally along the axis 23 of the flow channel 22 between a hard closed position 25a and a soft closed position 25b, and / or to move laterally between a soft closed position 25b and an open position 25c. The length of the engaging portion 45 can be, for example, approximately equal to the length of the blocking portion 42. However, the size of the engaging portion 45 in this invention is not particularly limited, as long as the actuating element 46 can actuate the blocking portion 42 of the gate 40 via the engaging portion 45 of the gate 40 to open or close the flow channel 22, it can be applied in this invention. Furthermore, for the sake of simplicity, therefore... Figures 3 to 6 The length of the joint 45 shown is a shorter length and is not a true proportion. When the gate 40 moves longitudinally between the hard-closed position 25a and the soft-closed position 25b, the position of the abutment area 44 of the gate 40 overlaps with the abutment area 24 of the hollow valve body 20. Moreover, the turbulence groove 50 of the present invention can increase the time required for fluid (such as gas) to flow from one side of the vacuum valve 10, through the surface 43 of the gate 40, through the space between the abutment area 44 of the gate 40 and the abutment area 24 of the hollow valve body 20, and then into the other side of the vacuum valve 10.

[0061] Taking vacuum valve 10 as a pendulum valve as an example, the actuating element 46 series is, for example, a design with lateral movement (e.g., a rotary motor or a lateral drive cylinder and connecting rod combination (e.g.) Figure 1As shown) and the combined structure of longitudinal movement design (longitudinal drive cylinder), the actuating element 46 can drive the joint 45 to perform rotation and longitudinal movement, thereby driving the blocking part 42 of the gate 40 to move longitudinally and laterally via the joint 45, so that the blocking part 42 moves longitudinally between the hard closed position 25a and the soft closed position 25b and moves laterally between the soft closed position 25b and the open position 25c. The aforementioned lateral movement position is, for example, a horizontal lateral movement position. Vacuum valve 10 may also be, for example, a flap gate valve. Actuating element 46 has, for example, a combination structure of lateral movement design (e.g., a rotary motor or a combination of lateral drive cylinder and connecting rod) and longitudinal movement design (longitudinal drive cylinder). Actuating element 46 can drive joint 45 to perform rotation and longitudinal movement, thereby driving the blocking part 42 of gate 40 to move longitudinally and laterally via joint 45, so that the blocking part 42 moves longitudinally between hard closed position 25a and soft closed position 25b and laterally between soft closed position 25b and open position 25c. The aforementioned lateral movement position is, for example, a flip-type lateral movement position.

[0062] Since vacuum valves such as pendulum valves and flap gate valves are already well-established technologies, those skilled in the art will understand how the design of the actuating element 46 drives the blocking portion 42 of the gate 40 to move when the vacuum valve 10 is a pendulum valve, flap gate valve, or other valve. Furthermore, the design of the actuating element 46 is not the focus of this invention; therefore, as long as the vacuum valve 10 can drive the blocking portion 42 of the gate 40 to move, it falls within the scope of protection claimed in this invention.

[0063] Similarly, depending on the type of vacuum valve, the actuating element 46 of the vacuum valve 10 of the present invention may only cause the blocking portion 42 of the gate 40 to move longitudinally between the hard closed position 25a and the soft closed position 25b, or only cause the blocking portion 42 of the gate 40 to move laterally between the soft closed position 25b and the open position 25c. Since the design of the actuating element 46 is not the focus of the improvement of the present invention, as long as the vacuum valve 10 can drive the blocking portion 42 of the gate 40 to move longitudinally and / or laterally, it falls within the scope of protection claimed by the present invention.

[0064] Continuing on, in this invention, when the blocking portion 42 of the gate 40 is in the hard-closed position 25a, the abutting area 44 of the surface 43 of the blocking portion 42 of the gate 40 abuts against the surface of the abutting area 24 of the hollow valve body 20 to seal the flow channel 22. For example, the surface of the abutting area 24 is, for example, the surface 28 of the abutting plate 27 of the drive cylinder in a pendulum valve. However, depending on the design of the vacuum valve, the abutting plate 27 of the drive cylinder may be omitted in the pendulum valve, that is, the surface of the abutting area 24 may be the surface of the hollow valve body 20. The abutting area 44 of the surface 43 of the blocking portion 42 is, for example, provided with a sealing ring 47 (such as an O-ring), so that the blocking portion 42 of the gate 40 can, for example, abut against the surface of the abutting area 24 with the sealing ring 47 on the abutting area 44. When the blocking portion 42 of the gate 40 moves from the hard closed position 25a to the soft closed position 25b along the axis 23 of the flow channel 22, the surface 43 of the blocking portion 42 of the gate 40 is, for example, correspondingly separated from the surface on the contact area 24 (e.g., the contact plate 27 of the drive cylinder or the surface of the hollow valve body 20), that is, it does not contact the surface on the contact area 24 of the hollow valve body 20.

[0065] One technical feature of this invention is that the surface 43 of the blocking portion 42 of the gate 40 has at least one turbulence groove 50, and the gate 40 extends the time for gas flow through the flow channel 22 by means of the turbulence groove 50 located in the flow channel 22, thereby reducing the gas conductance value of the flow channel 22 of the hollow valve body 20. Therefore, when the blocking portion 42 of the gate 40 moves between the hard closed position 25a and the soft closed position 25b, the gate 40 of this invention can maintain a very small gas conductance value by means of the turbulence groove 50, thereby reducing the change in gas conductance value caused by gas flow passing through the gate 40, thus achieving the effect of controlling the gas conductance value. Wherein, if the vacuum valve 10 is located between the process chamber and the vacuum pump, the gas mentioned above is gas from the process chamber. Similarly, if the vacuum valve 10 is located between the atmospheric environment and the vacuum pump, the gas mentioned above is gas from the atmosphere or a separately supplied gas.

[0066] Furthermore, the surface 43 of the blocking portion 42, outside the abutment area 44, preferably, but not limited to, has a flat flange, i.e., a flat flange. This allows the blocking portion 42 of the gate 40 to move from the hard-closed position 25a along the axis 23 of the flow channel 22 to any position in the soft-closed position 25b, so that the flat flange outside the abutment area 44 of the blocking portion 42 is always located within the abutment area 24 and maintains the same distance from the surface of the abutment area 24. Through this design, the width of the flange outside the abutment area 44 of the blocking portion 42 (i.e., outside the sealing ring 47) can be effectively reduced. When the blocking portion 42 of the gate 40 is in the open position 25c, the blocking portion 42 of the gate 40 can be partially located on the side of the flow channel 22 to partially overlap the flow channel 22 (i.e., partially open the valve port), or entirely located on one side of the flow channel 22 (i.e., fully open the valve port). When the blocking portion 42 of the gate 40 moves longitudinally along the axis 23 of the flow channel 22 between the hard-closed position 25a and the soft-closed position 25b, the center of the turbulence groove 50 of the gate 40 preferably overlaps with the axis 23 of the flow channel 22. Taking the turbulence groove 50 as an annular groove, a plurality of concentric annular grooves, a left vortex groove, or a right vortex groove as an example, the center of the turbulence groove 50 is, for example, the center of the blocking portion 42.

[0067] In summary, compared with existing structures, the vacuum valve and its gate of the present invention have the following advantages: 1. The gate of the present invention utilizes surface structure to increase gas travel and generate a turbulence effect, which can increase airflow time and thus reduce gas conductivity. 2. The gate of the present invention has turbulence grooves, which can generate turbulence to increase airflow time and thus reduce gas conductivity. 3. The gate of the present invention has turbulence grooves, which can control gas conductivity, thereby preventing problems caused by excessive changes in gas conductivity when the vacuum valve is pumping or depressurizing. 4. The gate of the present invention has turbulence grooves, which can increase the structural strength of the gate, making it less prone to deformation, and has a lower manufacturing cost.

[0068] The above description is illustrative only and not restrictive. Any equivalent modifications or alterations made without departing from the spirit and scope of this invention should be included in the appended claims.

Claims

1. A vacuum valve, characterized in that, Include: A hollow valve body having a flow channel and an abutment area surrounding the flow channel; and A gate, movably disposed within the hollow valve body of the vacuum valve, has a blocking portion that moves longitudinally along an axis of the flow channel between a hard-closed position and a soft-closed position. In the hard-closed position, a contact area of ​​the blocking portion abuts against a surface of the contact area of ​​the hollow valve body to seal the flow channel. The surface of the blocking portion has at least one flow-disrupting groove. In the soft-closed position, the contact area of ​​the surface of the shielding portion of the gate is disengaged from the surface of the contact area of ​​the hollow valve body, and the gate extends the time for a gas to pass through the surface of the shielding portion of the gate and through the flow channel by means of the turbulence groove located in the flow channel, thereby reducing the gas conductance value of the flow channel of the hollow valve body. The turbulence groove of the gate is at least one annular groove, a plurality of concentric annular grooves, a left vortex groove, or a right vortex groove.

2. The vacuum valve as described in claim 1, characterized in that, The turbulence channel of the gate has a continuous sidewall.

3. The vacuum valve as described in claim 1, characterized in that, The width of the top of the turbulence channel of the gate is greater than the width of the bottom of the channel, and the turbulence channel of the gate has an inclined sidewall.

4. The vacuum valve as described in claim 1, characterized in that, The surface of the shielding part of the gate is a flat surface, and the turbulence groove is recessed on the surface of the shielding part of the gate.

5. The vacuum valve as described in claim 1, characterized in that, The blocking portion of the gate further moves laterally between an open position and a soft-close position. In the open position, the blocking portion of the gate is partially located on one side of the flow channel to partially overlap the flow channel, or in the open position, the blocking portion of the gate is entirely located on one side of the flow channel.

6. The vacuum valve as described in claim 1, characterized in that, The gate also has a connecting part that connects the blocking part and the actuating element, and the actuating element moves the blocking part of the gate longitudinally between the soft-closed position and the hard-closed position via the connecting part.

7. The vacuum valve as described in claim 1, characterized in that, When the blocking portion of the gate moves longitudinally along the axis of the flow channel between the soft-close position and the hard-close position, the center of the turbulence groove of the gate overlaps with the axis of the flow channel.

8. The vacuum valve as described in claim 1, characterized in that, The gate's shielding portion has a sealing ring on its contact area.

9. The vacuum valve as described in claim 1, characterized in that, The surface of the gate is a flat flange outside the contact area.

10. A gate, movably disposed within a hollow valve body of a vacuum valve, the hollow valve body having a flow channel and an abutment area surrounding the flow channel, characterized in that: The gate has a blocking portion that moves longitudinally between a hard-closed position and a soft-closed position along an axis of the flow channel of the hollow valve body. In the hard-closed position, a contact area of ​​a surface of the blocking portion of the gate abuts against a surface of the contact area of ​​the hollow valve body to seal the flow channel. The surface of the blocking portion of the gate has at least one turbulence groove. In the soft-closed position, the contact area of ​​the surface of the blocking portion of the gate is disengaged from the surface of the contact area of ​​the hollow valve body. The gate extends the time for gas to pass through the flow channel by the turbulence groove located in the flow channel, thereby reducing the gas conductance of the flow channel of the hollow valve body. The turbulence groove of the gate is at least one annular groove, a plurality of concentric annular grooves, a left vortex groove, or a right vortex groove.

11. The gate as described in claim 10, characterized in that, The turbulence channel of the gate has a continuous sidewall.

12. The gate as described in claim 10, characterized in that, The width of the top of the turbulence channel of the gate is greater than the width of the bottom of the channel, and the turbulence channel of the gate has an inclined sidewall.

13. The gate as described in claim 10, characterized in that, The surface of the shielding part of the gate is a flat surface, and the turbulence groove is recessed on the surface of the shielding part of the gate.

14. The gate as described in claim 10, characterized in that, The gate's shielding portion has a sealing ring on its contact area.

15. The gate as described in claim 14, characterized in that, The surface of the gate is a flat flange outside the contact area.

Images