High-precision liquid flow metering device based on screw drive

Abstract

The utility model relates to flowmeter technical field especially relates to a kind of high-precision liquid flow metering device based on screw drive, it include: barrel, first connecting flange, second connecting flange, bearing end cover, first screw rotor, second screw rotor, counting code disc, pulse sensor;Wherein, the barrel inside hollow, the first connecting flange is arranged in one end of the barrel, the second connecting flange is arranged in the other end of the barrel, the first screw rotor with the second screw rotor is arranged in the barrel inside and the tooth surface of the first screw rotor with the tooth surface of the second screw rotor is mutually engaged, the first screw rotor is close to the second connecting flange and the end of counting code disc is set, the pulse sensor with the lateral surface of the barrel is screw connection, the bearing end cover is arranged between the first connecting flange and the barrel.The utility model improves the measurement accuracy.

Description

Technical Field

[0001] This utility model relates to the field of flow meter technology, and in particular to a high-precision liquid flow metering device based on screw drive. Background Technology

[0002] Liquid volumetric flow meters are the most accurate type of flow meter. They use mechanical measuring elements to continuously divide the fluid into individual known volume portions, and measure the total flow volume by repeatedly filling and discharging that volume portion.

[0003] Chinese Patent Publication No. CN222926236U discloses a high-precision twin-screw flow meter, comprising: a metering housing, a first screw rotor, a second screw rotor, a front bearing housing, a rear bearing housing, a front end cover, and a rear end cover. The rear end cover is equipped with a rotary encoder connected to the second screw rotor for measuring its rotational speed. The rotary encoder is located outside the metering chamber. This high-precision twin-screw flow meter uses a rotary encoder directly connected to the second screw rotor to measure flow rate by measuring the rotational speed of the second screw rotor. Since the rotary encoder is located outside the metering chamber, it does not affect the detection of the rotational speed of the second screw rotor regardless of the type of fluid being measured, thus improving measurement accuracy.

[0004] It can be seen that the technical solution does not consider the influence of the number of heads of the spiral rotor on the change of fluid volume, nor does it consider that the superposition of multiple bearings will aggravate installation errors and vibrations, thus leading to poor measurement accuracy. Utility Model Content

[0005] Therefore, this utility model provides a high-precision liquid flow metering device based on screw drive to overcome the problems in the prior art that do not consider the influence of the number of screw rotor heads on the change of fluid volume, and do not consider that the superposition of multiple bearings will aggravate installation errors and vibrations, thus leading to poor metering accuracy.

[0006] To achieve the above objectives, this utility model provides a high-precision liquid flow metering device based on screw drive, comprising:

[0007] The device comprises a cylindrical body, a first connecting flange, a second connecting flange, a bearing end cap, a first screw rotor, a second screw rotor, a counting code disk, and a pulse sensor. The cylindrical body is hollow. The first connecting flange is located at one end of the cylindrical body, and the second connecting flange is located at the other end. The first and second screw rotors are disposed inside the cylindrical body, with the tooth surfaces of the first and second screw rotors meshing with each other. A counting code disk is fitted onto the end of the first screw rotor near the second connecting flange. The pulse sensor is threaded to the side of the cylindrical body. The bearing end cap is located between the first connecting flange and the cylindrical body. The first connecting flange has an inlet communicating with the cylindrical body, and the second connecting flange has an outlet communicating with the cylindrical body.

[0008] Furthermore, it also includes a first bearing, a second bearing, a third bearing, and a fourth bearing; wherein, the bearing end cover is correspondingly provided with the first bearing and the third bearing for supporting the first screw rotor and the second screw rotor respectively, the second bearing is disposed at one end of the first screw rotor disposed on the counting code disk, the second bearing is disposed inside the counting code disk, and the fourth bearing is disposed at the end of the second screw rotor away from the third bearing.

[0009] Furthermore, the first screw rotor is a double-ended screw, and the second screw rotor is a triple-ended screw, with the convex teeth of the first screw rotor and the concave teeth of the second screw rotor meshing with each other.

[0010] Furthermore, the inner surface of the cylinder and the outer contour surfaces of the meshing first and second screw rotors form several measuring cavities.

[0011] Furthermore, the bearing end cover is bolted to the first connecting flange and the cylinder body through a plurality of circumferentially arranged screw holes, wherein the center of each screw hole is located on the same circumference with the central axis of the bearing end cover as the center.

[0012] Furthermore, the bearing end cover is also provided with a plurality of water inlets, which are located on both sides of the mounting holes on the bearing end cover for respectively mounting the first bearing and the third bearing, and are located inside the circumference of the screw hole.

[0013] Furthermore, the first bearing, the second bearing, the third bearing, and the fourth bearing are all deep groove ball bearings.

[0014] Furthermore, the first screw rotor has a keyway that mates with a flat key at one end near the second connecting flange, and the inner ring of the counting code disk has a limiting groove that mates with a flat key. The counting code disk is mounted to one end of the first screw rotor via a flat key.

[0015] Compared with the prior art, the beneficial effect of this utility model is that it adopts a meshing structure of a double-headed screw and a triple-headed screw. The convex teeth of the double-headed screw and the concave teeth of the triple-headed screw are tightly engaged, making the volume change of the measuring cavity smoother. Compared with the traditional screw with the same number of heads, this design reduces fluid backflow and pulsation, and the volume division is more uniform, thereby reducing the flow pulsation error.

[0016] Furthermore, this invention utilizes four deep groove ball bearings to support the first and second screw rotors. The low friction characteristics of the deep groove ball bearings reduce mechanical resistance and avoid coaxiality deviations caused by multiple bearings stacking, thereby ensuring the sealing of the measurement.

[0017] Furthermore, this invention features a counting code disk connected to the end of the first screw rotor via a flat key, and a pulse sensor independently mounted on the side of the cylinder, which physically isolates the interference of the fluid environment on signal acquisition, thereby improving measurement accuracy.

[0018] Furthermore, this utility model also provides a water inlet on the bearing end cover between the first connecting flange and the cylinder. The water inlet is located on both sides of the bearing mounting hole. The water inlet works in conjunction with the inlet of the first connecting flange to divert the fluid to be measured into the measuring chamber, thereby improving the measurement accuracy. Attached Figure Description

[0019] Figure 1 This is an axial sectional view of a high-precision liquid flow metering device based on screw drive, according to an embodiment of this utility model.

[0020] Figure 2 This is a schematic diagram of the structure of the first screw rotor in an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of the structure of the second screw rotor in an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the structure of the counting code disk according to an embodiment of the present invention;

[0023] Figure 5 This is a front view of the bearing end cover according to an embodiment of the present utility model;

[0024] In the diagram, 1. Cylinder; 2. First connecting flange; 201. Inlet; 3. Second connecting flange; 301. Outlet; 4. Bearing end cover; 401. Screw hole; 402. Mounting hole; 403. Water inlet; 5. First screw rotor; 501. Keyway; 6. Second screw rotor; 7. Counting code disk; 701. Limiting groove; 8. Pulse sensor; 9. First bearing; 10. Second bearing; 11. Third bearing; 12. Fourth bearing; 13. Measuring chamber; 14. Flat key. Detailed Implementation

[0025] To make the objectives, features, and advantages of this utility model more apparent and understandable, the technical solutions in the embodiments of this utility model are clearly and completely described. Obviously, the embodiments described below are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] It should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this utility model.

[0027] In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0028] In the description of the embodiments of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0029] Please see Figure 1-5 The following are, respectively, axial sectional views of a high-precision liquid flow metering device based on screw drive according to an embodiment of the present invention; structural schematic diagram of the first screw rotor according to an embodiment of the present invention; structural schematic diagram of the second screw rotor according to an embodiment of the present invention; structural schematic diagram of the counting code disk according to an embodiment of the present invention; and front view of the bearing end cover according to an embodiment of the present invention.

[0030] This utility model provides a high-precision liquid flow metering device based on screw drive, comprising:

[0031] The system comprises a cylinder 1, a first connecting flange 2, a second connecting flange 3, a bearing end cap 4, a first screw rotor 5, a second screw rotor 6, a counting code disk 7, and a pulse sensor 8. The cylinder 1 is hollow. The first connecting flange 2 is located at one end of the cylinder 1, and the second connecting flange 3 is located at the other end of the cylinder 1. The first screw rotor 5 and the second screw rotor 6 are located inside the cylinder 1, with the tooth surfaces of the first screw rotor 5 and the second screw rotor 6 meshing with each other. A counting code disk 7 is fitted onto the end of the first screw rotor 5 closest to the second connecting flange 3. The pulse sensor 8 is threaded to the side of the cylinder 1. The bearing end cap 4 is located between the first connecting flange 2 and the cylinder 1. The first connecting flange 2 has an inlet 201 communicating with the cylinder 1, and the second connecting flange 3 has an outlet 301 communicating with the cylinder 1.

[0032] In this embodiment, the cylinder 1 is made of 316L stainless steel.

[0033] Specifically, it also includes a first bearing 9, a second bearing 10, a third bearing 11, and a fourth bearing 12; wherein, the bearing end cover 4 is correspondingly provided with the first bearing 9 and the third bearing 11 for supporting the first screw rotor 5 and the second screw rotor 6 respectively, the second bearing 10 is disposed at one end of the first screw rotor 5 disposed on the counting disk 7, the second bearing 10 is disposed inside the counting disk 7, and the fourth bearing 12 is disposed at the end of the second screw rotor 6 away from the third bearing 11.

[0034] Specifically, the first screw rotor 5 is a double-ended screw, and the second screw rotor 6 is a triple-ended screw. The convex teeth of the first screw rotor 5 and the concave teeth of the second screw rotor 6 mesh with each other.

[0035] Specifically, the inner surface of the cylinder 1 and the outer contour surfaces of the first screw rotor 5 and the second screw rotor 6 that mesh with each other form a plurality of measuring cavities 13.

[0036] Specifically, the bearing end cover 4 is bolted to the first connecting flange 2 and the cylinder 1 respectively through a plurality of circumferentially arranged screw holes 401, wherein the center of each screw hole 401 is located on the same circumference with the central axis of the bearing end cover 4 as the center.

[0037] Specifically, the bearing end cover 4 is also provided with a plurality of water inlets 403, which are located on both sides of the first bearing 9 and the third bearing 11, and are located inside the circumference of the screw hole 401.

[0038] Specifically, screw hole 401 is an M12 screw hole 401.

[0039] Specifically, the first bearing 9, the second bearing 10, the third bearing 11, and the fourth bearing 12 are all deep groove ball bearings.

[0040] Specifically, the first screw rotor 5 is provided with a keyway 501 that mates with the flat key 14 at one end near the second connecting flange 3, and the inner ring of the counting code disk 7 is provided with a limiting groove 701 that mates with the flat key 14. The counting code disk 7 is installed at one end of the first screw rotor 5 via the flat key 14.

[0041] The working process of this utility model is as follows: the liquid to be tested enters from the inlet 201, and is then diverted by the inlet 403, which drives the first screw rotor 5 and the second screw rotor 6 to rotate in opposite directions; the liquid to be tested is divided into the measuring chamber 13 by the meshing tooth surface, and a fixed volume is discharged every one revolution; the first screw rotor 5 drives the counting code disk 7 to rotate, the pulse sensor 8 captures the change of the light transmission hole, outputs the number of pulses, and calculates the flow rate; the liquid to be tested is discharged from the outlet 301.

[0042] For those skilled in the art, based on the ideas of the embodiments of this utility model, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this utility model.

Claims

1. A high-precision liquid flow metering device based on screw drive, characterized in that, include: The device comprises a cylindrical body, a first connecting flange, a second connecting flange, a bearing end cap, a first screw rotor, a second screw rotor, a counting code disk, and a pulse sensor. The cylindrical body is hollow. The first connecting flange is located at one end of the cylindrical body, and the second connecting flange is located at the other end. The first and second screw rotors are disposed inside the cylindrical body, with the tooth surfaces of the first and second screw rotors meshing with each other. A counting code disk is fitted onto the end of the first screw rotor near the second connecting flange. The pulse sensor is threaded to the side of the cylindrical body. The bearing end cap is located between the first connecting flange and the cylindrical body. The first connecting flange has an inlet communicating with the cylindrical body, and the second connecting flange has an outlet communicating with the cylindrical body.

2. The high-precision liquid flow metering device based on screw drive according to claim 1, characterized in that, It also includes a first bearing, a second bearing, a third bearing, and a fourth bearing; wherein, the bearing end cover is correspondingly provided with the first bearing and the third bearing for supporting the first screw rotor and the second screw rotor respectively, the second bearing is disposed at one end of the first screw rotor disposed on the counting code disk, the second bearing is disposed inside the counting code disk, and the fourth bearing is disposed at the end of the second screw rotor away from the third bearing.

3. The high-precision liquid flow metering device based on screw drive according to claim 1, characterized in that, The first screw rotor is a double-ended screw, and the second screw rotor is a triple-ended screw. The convex teeth of the first screw rotor and the concave teeth of the second screw rotor mesh with each other.

4. The high-precision liquid flow metering device based on screw drive according to claim 1, characterized in that, The inner surface of the cylinder and the outer contour surfaces of the meshing first and second screw rotors form several measuring cavities.

5. The high-precision liquid flow metering device based on screw drive according to claim 2, characterized in that, The bearing end cover is bolted to the first connecting flange and the cylinder body through a plurality of circumferentially arranged screw holes, wherein the center of each screw hole is located on the same circumference with the central axis of the bearing end cover as the center.

6. The high-precision liquid flow metering device based on screw drive according to claim 5, characterized in that, The bearing end cover is also provided with a plurality of water inlets, which are located on both sides of the mounting holes on the bearing end cover for respectively mounting the first bearing and the third bearing, and are located inside the circumference of the screw holes.

7. The high-precision liquid flow metering device based on screw drive according to claim 2, characterized in that, The first bearing, the second bearing, the third bearing, and the fourth bearing are all deep groove ball bearings.

8. The high-precision liquid flow metering device based on screw drive according to claim 1, characterized in that, The first screw rotor has a keyway that mates with a flat key at one end near the second connecting flange, and the inner ring of the counting code disk has a limiting groove that mates with a flat key. The counting code disk is mounted to one end of the first screw rotor via a flat key.

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