Tea fermentation device

Abstract

The invention discloses a tea fermentation device which comprises a fermentation cylinder, a front mounting seat and a rear mounting seat, the interior of the fermentation cylinder is divided into an air inlet cavity, a fermentation cavity and an exhaust cavity by a front partition plate and a rear partition net plate, and a plurality of uniformly distributed fermentation air inlet pipes are mounted between the front partition plate and the rear partition net plate; an inner strong magnetic block is fixedly installed on one side of the bottom of the front isolation plate and one side of the bottom of the rear isolation plate, and outer strong magnetic blocks attracting the inner strong magnetic block are arranged on the front installation base and the rear installation base. The air inlet end of the fermentation cylinder is connected with an impeller installed in an impeller outer cover through a connecting shaft, a movable air inlet and a static air inlet are connected with a connecting header pipe through a movable air inlet pipe and a static air inlet pipe respectively, and a heating device and an induced draft fan are installed on the connecting header pipe. The fermentation airflow system not only provides temperature, humidity and pressure suitable for fermentation for the inside of the fermentation cylinder, but also provides turning power for the fermentation cylinder; through a strong magnetic block structure, effective turning of the tea leaves in the fermentation cylinder is realized, and the fermentation quality is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of tea production devices, in particular to a tea fermentation device. Background Art

[0002] Tea fermentation is the core link that determines the flavor and quality of tea. The tea fermentation device is a device used to control the tea fermentation process. It usually consists of a closed indoor space and a control system for regulating fermentation conditions. The tea fermentation device can be used to produce various types of fermented tea, such as black tea, Pu'er tea, oolong tea, etc.

[0003] The basic principle of this device is to promote chemical reactions and microbial activities inside the tea leaves by adjusting environmental conditions such as temperature, humidity and ventilation, thereby realizing the fermentation process of tea leaves; the purpose of fermenting tea leaves is to change the chemical composition and aroma of tea leaves, giving them a special flavor and taste.

[0004] In the existing fermentation device, during the fermentation pile process, the temperature, humidity and air circulation conditions inside and outside the tea leaves vary greatly. In order to ensure the fermentation quality, the pile needs to be turned frequently. The turning process in the existing technology is only achieved by mechanical stirring or drum rotation. The mechanical stirring method can easily destroy the integrity of the tea leaves and affect the quality of the tea leaves. The traditional drum rotation method has a poor overall turning effect on tea leaves that stick together after fermentation, resulting in some tea leaves always remaining inside the tea pile, thereby over-fermenting. In view of the above problems, the present invention provides a solution. Summary of the Invention

[0005] The purpose of the present invention is to provide a tea fermentation device.

[0006] The above technical objectives of the present invention are achieved through the following technical solutions:

[0007] A tea fermentation device comprises a fermentation cylinder, a front mounting seat and a rear mounting seat, wherein the fermentation cylinder is transversely mounted on the front mounting seat and the rear mounting seat through a bearing, a feed port is provided in the middle of the fermentation cylinder, a detachable feed cover is installed on the feed port, a front partition plate and a rear partition plate are installed in the fermentation cylinder, the front partition plate and the rear partition plate are installed in the annular grooves at the front and rear ends of the fermentation cylinder, and can rotate relative to each other under the action of external force, the front partition plate and the rear partition plate divide the interior of the fermentation cylinder into an air intake chamber, a fermentation chamber and an exhaust chamber, The fermentation chamber is located between the air intake chamber and the exhaust chamber, and a number of evenly distributed turning plates are provided inside the fermentation chamber. A number of evenly distributed fermentation air intake pipes are installed between the front partition plate and the rear partition plate. The fermentation air intake pipe is located at an open end of the air intake chamber, and the fermentation air intake pipe is located at a closed end of the exhaust chamber. The fermentation air intake pipe is located in the fermentation chamber. There are evenly distributed air holes on the circumference of the middle section. An internal strong magnetic block is fixedly installed on one side of the bottom of the front partition plate and the rear partition plate. The front mounting seat and the rear mounting seat are provided with an internal strong magnetic block. The air inlet end of the fermentation cylinder is connected to the impeller installed in the impeller outer cover through a connecting shaft, and the impeller outer cover is fixedly installed on the impeller mounting seat. An air inlet hole communicating with the air inlet cavity is provided in the middle position of the impeller and the connecting shaft. A dynamic air inlet and a static air inlet are provided on the impeller outer cover. The static air inlet is provided in the middle position of the outer end of the impeller outer cover, and the dynamic air inlet is provided on the side of the impeller outer cover, and the dynamic air inlet is provided tangent to the outer circumference of the impeller. The dynamic air inlet and the static air inlet are respectively connected through dynamic air inlet pipes. The static air intake pipe is connected to the connecting main pipe, the dynamic air intake pipe is installed with a third solenoid valve, the static air intake pipe is installed with a fourth solenoid valve, the air intake end of the connecting main pipe is connected to the steam intake pipe and the air intake pipe through a three-way joint, a heating device and an induced draft fan are installed on the connecting main pipe, the other end of the steam intake pipe is connected to the atomizing device, the steam intake pipe is provided with a first solenoid valve, the air intake pipe is provided with a second solenoid valve; the outer end of the exhaust chamber is provided with a plurality of evenly distributed exhaust holes, and the outer sides of the exhaust holes are provided with sealing plates covering the exhaust holes.

[0008] Furthermore, at least three mounting holes are provided on the outside of the sealing plate, and a connecting screw is inserted in each mounting hole. One end of the connecting screw passes through the through hole on the fermentation cylinder and extends into the exhaust chamber. A limit block is provided on the end of the connecting screw extending into the exhaust chamber. A spring is installed on the connecting screw between the limit block and the fermentation cylinder, and the outer end of the connecting screw is threadedly engaged with the adjusting nut.

[0009] Furthermore, the cross section of the flipping plate is a fan-shaped structure, the flipping plate is hollow, and both ends are sealed.

[0010] Furthermore, the atomizing device includes an atomizing tank, an air pump and an atomizing head, the atomizing head is installed at the bottom of the inner cavity of the atomizing tank, the air pump is installed below the atomizing tank, the atomizing head includes an atomizing inner core, an atomizing outer core and a baffle, an air hole is provided in the middle of the atomizing inner core, the bottom end of the air hole is connected to the air pipe and the air pump through a joint, the atomizing outer core cover is closed on the outside of the atomizing inner core, and a gap is left between the atomizing outer core and the atomizing inner core for atomized water to pass through, the baffle is located above the atomizing inner core and the atomizing outer core, the baffle is connected to the atomizing inner core through a connecting rod, and the water inlet joint of the atomizing tank is arranged on the upper end side wall.

[0011] Furthermore, the heating device includes a shell and a plurality of resistance wires for heating installed inside the shell. The heating device is installed on the connecting main pipe through the air inlet and outlet ports at both ends.

[0012] Furthermore, both the front partition plate and the rear partition plate are provided with mounting frames for mounting the inner strong magnetic block. The mounting frame on the front partition plate is located on the air inlet cavity side, and the mounting frame on the rear partition plate is located on the exhaust cavity side.

[0013] Furthermore, both the outer strong magnetic block and the inner strong magnetic block are made of neodymium iron boron magnets.

[0014] Furthermore, the air inlet end of the air inlet hole is configured to be conical.

[0015] In summary, the present invention has the following beneficial effects:

[0016] 1. The present invention combines an impeller with a fermentation airflow system. The fermentation airflow system not only provides the fermentation cylinder with suitable temperature, humidity and pressure for fermentation, but also provides the fermentation cylinder with power for turning the compost.

[0017] 2. This invention realizes the purpose of preventing the air inlet pipe from rotating with the fermentation cylinder by designing the installation structure of the front partition and the rear partition plate, combined with the strong magnetic block structure, so that the bottom and outer circle tea leaves rotate with the fermentation cylinder, and the middle tea leaves move downward by their own gravity, thereby realizing the purpose of rotating the fermented tea leaves inside and outside, achieving effective material turning and ensuring fermentation quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a structural schematic diagram of the impeller part of the present invention;

[0020] Figure 3 is a cross-sectional view of the impeller portion of the present invention;

[0021] Figure 4 is a cross-sectional view of a fermentation cylinder of the present invention;

[0022] Figure 5 yes Figure 1 A partial enlarged schematic diagram;

[0023] Figure 6 It is a partial schematic diagram of the sealing cover;

[0024] Figure 7 It is a schematic diagram of the partial structure of the atomization device;

[0025] In the figure, 1. fermentation cylinder; 2. fermentation chamber; 3. air intake chamber; 4. exhaust chamber; 5. feed cover; 6. front partition; 7. rear partition; 8. front mounting base; 9. rear mounting base; 10. fermentation air intake pipe; 11. turning plate; 12. atomizing device; 13. air pump; 14. atomizing head; 15. water inlet connector; 16. steam inlet pipe; 17. solenoid valve 1; 18. air inlet pipe; 19. solenoid valve 2; 20. connecting main pipe; 21. heating device; 22. induced draft fan; 23. dynamic air intake pipe; 24. solenoid valve 3. 25. Impeller cover; 26. Impeller; 27. Impeller mounting seat; 28. Static air inlet pipe; 29. ​​Solenoid valve 4; 30. Dynamic air inlet; 31. Static air inlet; 32. Air inlet hole; 33. External strong magnetic block; 34. Internal strong magnetic block; 35. Mounting frame; 36. Bearing; 37. Sealing cover; 38. Exhaust hole; 39. Connecting screw; 40. Spring; 41. Limit block; 42. Adjusting nut; 43. Atomizer inner core; 44. Atomizer outer core; 45. Gap; 46. Air hole; 47. Baffle; 48. Connecting rod. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings, clearly and completely describing the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] like Figure 1-7As shown, a tea fermentation device includes a fermentation cylinder 1, a front mounting seat 8 and a rear mounting seat 9, the fermentation cylinder 1 is horizontally mounted on the front mounting seat 8 and the rear mounting seat 9 through a bearing 36, a feed port is provided in the middle position of the fermentation cylinder 1, a detachable feed cover 5 is installed on the feed port, a front partition plate 6 and a rear partition plate 7 are installed in the fermentation cylinder 1, the front partition plate 6 and the rear partition plate 7 are installed in the annular grooves at the front and rear ends of the fermentation cylinder 1, and can rotate relative to each other under the action of external force, the front partition plate 6 and the rear partition plate 7 divide the interior of the fermentation cylinder 1 into an air intake chamber 3, a fermentation chamber 2 and an exhaust chamber 4, the fermentation chamber 2 is located at the air intake chamber 3, and the exhaust chamber 4 is located at the air exhaust chamber 4. In the middle of the chamber 3 and the exhaust chamber 4, a number of evenly distributed turning plates 11 are provided inside the fermentation chamber 2, and a number of evenly distributed fermentation air inlet pipes 10 are installed between the front partition plate 6 and the rear partition plate 7. The fermentation air inlet pipe 10 is located at an open end of the air inlet chamber 3, and the fermentation air inlet pipe 10 is located at a closed end of the exhaust chamber 4. The fermentation air inlet pipe 10 is located in the fermentation chamber 2. The middle section is provided with evenly distributed air holes on the circumference. An inner strong magnetic block 34 is fixedly installed on one side of the bottom of the front partition plate 6 and the rear partition plate 7. An outer strong magnetic block 33 that attracts the inner strong magnetic block 34 is provided on the front mounting seat 8 and the rear mounting seat 9; the inlet of the fermentation cylinder 1 The air end is connected to the impeller 26 installed in the impeller outer cover 25 through a connecting shaft. The impeller outer cover 25 is fixedly mounted on the impeller mounting seat 27. An air inlet 32 ​​communicating with the air inlet cavity 3 is provided at the middle position between the impeller 26 and the connecting shaft. A dynamic air inlet 30 and a static air inlet 31 are provided on the impeller outer cover 25. The static air inlet 31 is provided at the middle position of the outer end of the impeller outer cover 25. The dynamic air inlet 30 is provided on the side of the impeller outer cover 25, and the dynamic air inlet 30 is tangent to the outer circumference of the impeller 26. The dynamic air inlet 30 and the static air inlet 31 are connected to the main air inlet 31 through the dynamic air inlet pipe 23 and the static air inlet pipe 28 respectively. The main connecting pipe 20 is connected to the main connecting pipe 20. A solenoid valve 3 24 is installed on the dynamic air intake pipe 23, and a solenoid valve 4 29 is installed on the static air intake pipe 28. The air intake end of the connecting manifold 20 is connected to the steam intake pipe 16 and the air intake pipe 18 via a tee joint. The connecting manifold 20 is equipped with a heating device 21 and an induced draft fan 22. The other end of the steam intake pipe 16 is connected to the atomizing device 12. A solenoid valve 17 is installed on the steam intake pipe 16, and a solenoid valve 2 19 is installed on the air intake pipe 18. The outer end of the exhaust chamber 4 is provided with a plurality of evenly distributed exhaust holes 38. The outer side of each exhaust hole 38 is provided with a sealing plate 37 covering the exhaust holes 38. All of the above solenoid valves are adjustable so that the air intake volume can be easily adjusted.

[0028] Further, such as Figure 1 and Figure 6As shown, at least three mounting holes are provided on the outside of the sealing plate 37, and a connecting screw 39 is inserted in each mounting hole. One end of the connecting screw 39 passes through the through hole on the fermentation cylinder 1 and extends into the exhaust chamber 4. A limit block 41 is provided on the end of the connecting screw 39 extending into the exhaust chamber 4. A spring 40 is provided on the connecting screw 39 between the limit block 41 and the fermentation cylinder 1. The outer end of the connecting screw 39 is threadedly engaged with the adjusting nut 42. By adjusting the matching length of the connecting screw 39 and the adjusting nut 42, the pressure at which the sealing plate 37 is pushed open can be adjusted, thereby adjusting the pressure in the entire fermentation cylinder 1.

[0029] For further reference, Figure 4 As shown, the cross section of the flipping plate 11 is a fan-shaped structure. The flipping plate 11 is hollow and sealed at both ends. Setting it into a fan shape can reduce dead corners that are difficult to clean due to the setting of the flipping plate 11.

[0030] Further, such as Figure 7 As shown, the atomizing device 12 includes an atomizing tank, an air pump 13 and an atomizing head 14. The atomizing head 14 is installed at the bottom of the inner cavity of the atomizing tank, and the air pump 13 is installed below the atomizing tank. The atomizing head 14 includes an atomizing inner core 43, an atomizing outer core 44 and a baffle 47. An air hole 46 is provided in the middle of the atomizing inner core 43. The bottom end of the air hole 46 is connected to the air pipe and the air pump 13 through a joint. The atomizing outer core 44 is covered on the outside of the atomizing inner core 43. A gap 45 is left between the atomizing core 44 and the atomizing core 43 for the atomized water to pass through. The baffle 47 is located above the atomizing core 43 and the atomizing outer core 44. The baffle 47 is connected to the atomizing core 43 via a connecting rod 48. The water inlet connector 15 of the atomizing tank is set on the upper side wall. When the high-speed gas blown by the air pump 13 passes through the gap between the baffle 47 and it, it will generate negative pressure. The negative pressure will suck the water in the atomizing tank up through the gap 45, causing it to hit the baffle 47, thereby atomizing the water. Similarly, you can also purchase a mature atomizing device on the market as a replacement according to your needs.

[0031] Furthermore, the heating device 21 includes an outer shell and a plurality of resistance wires for heating installed inside the outer shell. The heating device 21 is installed on the connecting main pipe 20 through the air inlet and outlet at both ends. The heating device 21 can also use commonly used heating equipment on the market according to actual needs. The heating device 21 only needs to energize the resistance wire to generate heat. The heat generation can be controlled by the current, and then the temperature is controlled. It is not described in detail here.

[0032] Furthermore, the front baffle 6 and the rear baffle 7 are both provided with a mounting frame 35 for mounting the inner strong magnetic block 34. The mounting frame 35 on the front baffle 6 is located on one side of the air inlet cavity 3, and the mounting frame 35 on the rear baffle 7 is located on one side of the exhaust cavity 4. Figure 1 and Figure 5As shown, the installation frame 35 is provided to facilitate the installation of the inner strong magnetic block 34 without affecting the tea leaves in the fermentation chamber 2.

[0033] Furthermore, the outer strong magnetic block 33 and the inner strong magnetic block 34 are both made of neodymium iron boron magnets. Through the strong magnetic attraction between the outer strong magnetic block 33 and the inner strong magnetic block 34, the front partition plate 6 and the rear partition plate 7 will not rotate with the rotation of the fermentation cylinder 1.

[0034] Further, such as Figure 2 As shown, the air inlet end of the air inlet hole 32 is configured to be conical, so as to facilitate air flow to enter the interior of the fermentation cylinder 1 through the air inlet hole 32 .

[0035] Working principle: open the feed cover 5, add the tea leaves to be fermented into the fermentation chamber 2 from the feed port of the fermentation cylinder 1, and control the airflow speed by adjusting the opening degree of solenoid valve 17 and solenoid valve 2 18 and the speed of the induced draft fan 22 according to the temperature, humidity, gas flow rate and pressure required for fermentation. Adjust the humidity of the airflow by controlling the air pressure of the air pump 13, control the temperature inside the fermentation cylinder 1 by controlling the current of the heating device 21, and control the pressure inside the fermentation cylinder 1 by adjusting the nut. During normal fermentation, solenoid valve 3 24 is closed, solenoid valve 4 29 is opened, and the fermentation air inlet pipe 10 sends gas with appropriate temperature, humidity and oxygen content into the fermentation chamber 2 for fermentation. When turning the compost is required, solenoid valve 29 is closed and solenoid valve 3 24 is opened. Simultaneously, the speed of induced draft fan 22 and the opening of solenoid valve 2 19 are increased as needed. High-speed airflow impacts the blades of impeller 26, driving fermentation drum 1 to rotate. However, due to the attraction of the strong magnetic block, the front baffle 6, rear screen 7, and fermentation inlet pipe 10 do not rotate with fermentation drum 1. The tea leaves at the bottom of fermentation drum 1 rotate upward with the turning plate 11, while the tea leaves above, driven by fermentation inlet pipe 10, rotate less with the turning plate 11 and mostly move downward by gravity, falling to the bottom of the fermentation chamber. This allows for effective turning without damaging the tea leaves' surface. After turning the compost, subsequent fermentation continues until fermentation is complete, at which point the feed port is turned downward for discharge.

[0036] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A tea fermentation device, comprising a fermentation cylinder (1), a front mounting seat (8) and a rear mounting seat (9), wherein the fermentation cylinder (1) is transversely mounted on the front mounting seat (8) and the rear mounting seat (9) via a bearing (36), a feed port is provided in the middle of the fermentation cylinder (1), and a detachable feed cover (5) is installed on the feed port, characterized in that: A front baffle (6) and a rear baffle (7) are installed in the fermentation cylinder (1). The front baffle (6) and the rear baffle (7) are installed in the annular grooves at the front and rear ends of the fermentation cylinder (1) and can rotate relative to each other under the action of external force. The front baffle (6) and the rear baffle (7) divide the interior of the fermentation cylinder (1) into an air intake chamber (3), a fermentation chamber (2) and an exhaust chamber (4). The fermentation chamber (2) is located between the air intake chamber (3) and the exhaust chamber (4). A plurality of evenly distributed turning plates (11) are provided inside the fermentation chamber (2). A plurality of evenly distributed fermentation air intake pipes (10) are installed between the front baffle (6) and the rear baffle (7). The fermentation air intake pipes (10) are provided with a plurality of evenly distributed turning plates (11). 0) is located at one end of the air inlet chamber (3) and is open, and the fermentation air inlet pipe (10) is located at one end of the air exhaust chamber (4) and is closed, and the fermentation air inlet pipe (10) is located in the fermentation chamber (2) and is provided with air holes evenly distributed on the circumference of the middle section thereof, and an inner strong magnetic block (34) is fixedly installed on one side of the bottom of the front isolation plate (6) and the rear isolation plate (7), and an outer strong magnetic block (33) for attracting the inner strong magnetic block (34) is provided on the front mounting seat (8) and the rear mounting seat (9); the air inlet end of the fermentation cylinder (1) is connected to the impeller (26) installed in the impeller outer cover (25) through a connecting shaft, and the impeller outer cover (25) is fixedly installed on the impeller mounting seat (27), An air inlet (32) communicating with the air inlet cavity (3) is provided between the impeller (26) and the connecting shaft. A dynamic air inlet (30) and a static air inlet (31) are provided on the impeller cover (25). The static air inlet (31) is provided at the middle position of the outer end of the impeller cover (25). The dynamic air inlet (30) is provided on the side of the impeller cover (25). The dynamic air inlet (30) is provided tangentially to the outer circumference of the impeller (26). The dynamic air inlet (30) and the static air inlet (31) are connected to the connecting main pipe (20) through a dynamic air inlet pipe (23) and a static air inlet pipe (28) respectively. The dynamic air inlet pipe (23) is provided with a solenoid valve (24). ), a solenoid valve four (29) is installed on the static air intake pipe (28), the air intake end of the connecting main pipe (20) is connected to the steam intake pipe (16) and the air intake pipe (18) through a three-way joint, a heating device (21) and an induced draft fan (22) are installed on the connecting main pipe (20), the other end of the steam intake pipe (16) is connected to the atomizing device (12), a solenoid valve one (17) is provided on the steam intake pipe (16), and a solenoid valve two (19) is provided on the air intake pipe (18); the outer end of the exhaust chamber (4) is provided with a plurality of evenly distributed exhaust holes (38), and the outer side of the exhaust holes (38) is provided with a sealing plate (37) covering the exhaust holes (38).

2. A tea fermentation device according to claim 1, characterized in that: At least three mounting holes are provided on the outer side of the sealing plate (37), and a connecting screw (39) is inserted into each mounting hole. One end of the connecting screw (39) passes through the through hole on the fermentation cylinder (1) and extends into the exhaust chamber (4). A limiting block (41) is provided on the end of the connecting screw (39) extending into the exhaust chamber (4). A spring (40) is mounted on the connecting screw (39) between the limiting block (41) and the fermentation cylinder (1), and the outer end of the connecting screw (39) is threadedly engaged with an adjusting nut (42).

3. A tea fermentation device according to claim 2, characterized in that: The cross section of the turning plate (11) is a fan-shaped structure, the turning plate (11) is hollow, and both ends are sealed.

4. A tea fermentation device according to claim 3, characterized in that: The atomizing device (12) includes an atomizing tank, an air pump (13) and an atomizing head (14). The atomizing head (14) is installed at the bottom of the inner cavity of the atomizing tank, and the air pump (13) is installed below the atomizing tank. The atomizing head (14) includes an atomizing inner core (43), an atomizing outer core (44) and a baffle (47). An air hole (46) is provided in the middle of the atomizing inner core (43). The bottom end of the air hole (46) is connected to the air pipe and the air pump through a joint. The atomizing outer core (44) is connected to the atomizing inner core (43), and a gap (45) is left between the atomizing outer core (44) and the atomizing inner core (43) for atomized water to pass through. The baffle (47) is located above the atomizing inner core (43) and the atomizing outer core (44), and the baffle (47) is connected to the atomizing inner core (43) through a connecting rod (48). The water inlet connector (15) of the atomizing tank is arranged on the upper side wall.

5. A tea fermentation device according to claim 4, characterized in that: The heating device (21) comprises a shell and a plurality of resistance wires for heating installed inside the shell. The heating device (21) is installed on the connecting main pipe (20) through the air inlet and outlet ports at both ends.

6. A tea fermentation device according to claim 5, characterized in that: The front partition plate (6) and the rear partition plate (7) are both provided with a mounting frame (35) for mounting the internal strong magnetic block (34); the mounting frame (35) on the front partition plate (6) is located on one side of the air inlet cavity (3), and the mounting frame (35) on the rear partition plate (7) is located on one side of the air outlet cavity (4).

7. A tea fermentation device according to claim 6, characterized in that: The outer strong magnetic block (33) and the inner strong magnetic block (34) are both made of neodymium iron boron magnets.

8. A tea fermentation device according to claim 2, characterized in that: The air inlet end of the air inlet hole (32) is configured to be tapered.

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