Micro-gear flowmeter

Abstract

The utility model discloses a kind of micro pinion flowmeters, including shell, including shell inside having measuring cavity, two groups of gear meshing are provided in measuring cavity, measuring cavity is respectively provided with inlet area and discharge area in two groups of gear opposite ends, each group of gear top is provided with circular table protrusion, the outer surface of each group of gear is covered with wear-resistant coating, shell includes the bottom shell and upper cover combined, bottom shell is provided with medium inlet group of intercommunication inlet area, and medium outlet group of intercommunication discharge area, upper cover bottom wall is provided with two groups of embedding groove, two groups of embedding groove are respectively for two groups of circular table protrusion corresponding embedding and form ladder cooperation, the junction surface of bottom shell and upper cover is sequentially distributed with primary seal ring and secondary seal ring from inside to outside;Primary seal ring and secondary seal ring double-seal design improve the pressure resistance of flowmeter and sealing reliability, avoid the appearance of external leakage after sealing ring damage or aging.

Description

Technical Field

[0001] This utility model relates to the field of flow measurement technology, specifically to a micro gear flow meter. Background Technology

[0002] Gear flow meters are a type of volumetric flow meter. They are widely used in industries such as petroleum, chemical, and food due to their high accuracy, good repeatability, and insensitivity to viscosity changes. They are especially suitable for measuring the flow rate of high-viscosity media. The core structure of a gear flow meter is a precision-machined metering chamber containing a pair of meshing gears.

[0003] In long-term use in harsh industrial environments, gear flow meters can experience internal and external leakage. Internal leakage occurs due to severe wear on the meshing surfaces and tooth tips of the gears, which wears down the gap between the gears and the measuring chamber wall, leading to increased internal leakage, reduced metering accuracy, and a shorter service life. External leakage occurs when fluid leaks from the junction of the flow meter housing and the cover plate, which not only affects accuracy but also causes media loss and pollution in the external environment. Based on these issues, a miniature gear flow meter is proposed that can solve these problems. Utility Model Content

[0004] The purpose of this invention is to provide a micro gear flow meter to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a micro gear flow meter, including a housing, and a measuring cavity inside the housing, wherein two sets of meshing gears are arranged in the measuring cavity, and an inlet area and an outlet area are respectively arranged at the opposite ends of the two sets of gears in the measuring cavity, and a frustum protrusion is provided on the top of each set of gears, and a wear-resistant coating is applied to the outer surface of each set of gears;

[0006] The housing includes a combined bottom shell and a top cover. The bottom shell has a medium inlet group that communicates with the inlet area and a medium outlet group that communicates with the outlet area. The bottom wall of the top cover is provided with two sets of grooves, and the two sets of grooves are respectively for the two sets of frustum protrusions to be inserted into and form a stepped fit.

[0007] At the joint surface between the bottom shell and the top cover, a primary sealing ring and a secondary sealing ring are distributed sequentially from the inside to the outside.

[0008] As a preferred technical solution, both sets of gears are integrally machined.

[0009] As a preferred technical solution, the wear-resistant coating is a diamond-like carbon coating or a tungsten carbide coating.

[0010] As a preferred technical solution, the bottom shell and the top cover are joined together by multiple sets of bolt assemblies to form the measuring cavity.

[0011] As a preferred technical solution, the medium inlet group includes a medium inlet cross channel and a medium inlet vertical channel, and the medium outlet group includes a medium outlet cross channel and a medium outlet vertical channel.

[0012] As a preferred technical solution, the bottom wall of the upper cover is provided with a receiving inlet cavity and a receiving outlet cavity, the receiving inlet cavity being directly above the receiving area and the receiving outlet cavity being directly above the discharging area.

[0013] As a preferred technical solution, the top wall of the bottom shell is provided with a primary groove and a secondary groove for placing the primary sealing ring and the secondary sealing ring, respectively.

[0014] As a preferred technical solution, a transverse ring is connected to the inner side of the primary sealing ring. The transverse ring is located outside the primary receiving groove and contacts the top wall of the bottom shell and the bottom wall of the upper cover. The transverse ring has a groove facing the measuring cavity.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] The dual sealing design of primary and secondary sealing rings improves the pressure resistance and sealing reliability of the flow meter, and avoids external leakage after the sealing rings are damaged or aged.

[0017] The truncated cone protrusion is embedded and forms a stepped fit. The stepped fit structure achieves precise axial positioning and creates a labyrinthine sealing effect, making it difficult for the medium to enter the groove and come into contact with the top of the truncated cone protrusion, thus reducing wear on the truncated cone protrusion. The wear-resistant coating increases the hardness of the outer surface of the gear and has an extremely low coefficient of friction, avoiding wear in a short period of time, ensuring accurate metering, and significantly extending its service life.

[0018] The inlet and outlet chambers serve as buffer zones for the fluid medium, effectively absorbing pressure pulsations before the fluid enters and leaves the gear meshing area. This makes the flow field more uniform and stable, thereby reducing measurement errors caused by flow field disturbances and improving the signal-to-noise ratio of the output signal. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure;

[0020] Figure 2 A schematic diagram showing two sets of meshing gears located inside the measuring cavity;

[0021] Figure 3 A schematic diagram showing the positional relationship between the medium inlet group, the medium outlet group, and the measuring cavity;

[0022] Figure 4 This is a schematic diagram of the upper cover structure;

[0023] In the diagram: 10. Bottom shell; 11. Primary reservoir; 12. Secondary reservoir; 13. Primary sealing ring; 131. Horizontal ring; 132. Tank body; 14. Secondary sealing ring; 15. Medium inlet horizontal channel; 16. Medium inlet vertical channel; 17. Medium outlet horizontal channel; 18. Medium outlet vertical channel; 20. Top cover; 21. Embedded groove; 22. Receiving inlet cavity; 23. Receiving outlet cavity; 30. Measuring cavity; 31. Inlet area; 32. Outlet area; 40. Gear; 41. Frustum protrusion. Detailed Implementation

[0024] The following is a detailed description of a miniature gear flow meter according to an embodiment of the present disclosure, with reference to the accompanying drawings. To make the objectives, technical solutions, and advantages of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present disclosure.

[0025] Therefore, the following detailed description of embodiments of the present disclosure provided in conjunction with the accompanying drawings is not intended to limit the scope of the claimed disclosure, but merely to illustrate selected embodiments of the disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of the present disclosure without inventive effort are within the scope of protection of the present disclosure.

[0026] Example 1: A micro gear 40 flow meter:

[0027] See Figure 1 The housing has a measuring cavity 30 inside. The housing includes a bottom shell 10 and a top cover 20 that are joined together. The bottom shell 10 and the top cover 20 are joined together by multiple sets of bolt assemblies to form a sealed measuring cavity 30.

[0028] See Figure 2 , Figure 3 At the mating surface of the bottom shell 10 and the top cover 20, primary sealing ring 13 and secondary sealing ring 14 are distributed sequentially from the inside to the outside. Using multiple sets of bolts, preload can be applied evenly to ensure that the sealing rings on the mating surface are compressed evenly, thereby achieving a reliable static seal. The dual sealing design of primary sealing ring 13 and secondary sealing ring 14 improves the pressure resistance and sealing reliability of the flow meter and avoids external leakage after the inner sealing ring is damaged or aged.

[0029] See Figure 2The measuring chamber 30 contains two sets of meshing gears 40. At the opposite ends of the two sets of gears 40, the measuring chamber 30 has an inlet area 31 and an outlet area 32. Each set of gears 40 has a frustum-shaped protrusion 41 on its top. The bottom wall of the upper cover 20 has two sets of grooves 21, which are used to insert the two sets of frustum-shaped protrusions 41 into a stepped fit. This stepped fit structure achieves precise axial positioning and creates a labyrinthine sealing effect, making it difficult for the medium to enter the grooves 21 and contact the top of the frustum-shaped protrusions 41, thus reducing wear on the protrusions. Furthermore, the outer surface of each set of gears 40 is covered with a wear-resistant coating, which is either a diamond-like carbon coating or a tungsten carbide coating. This wear-resistant coating increases the hardness of the outer surface of the gears 40 and has an extremely low coefficient of friction. It also has excellent chemical inertness, preventing reaction with the medium and peeling off, thus avoiding wear in a short period, ensuring accurate measurement, and significantly extending its service life.

[0030] See Figure 3 The bottom shell 10 has a medium inlet group that connects to the inlet area 31 and a medium outlet group that connects to the outlet area 32. The medium inlet group includes a medium inlet cross channel 15 and a medium inlet vertical channel 16, and the medium outlet group includes a medium outlet cross channel 17 and a medium outlet vertical channel 18. This L-shaped flow channel design makes it easy to connect the flow meter to the external pipeline system through a standard thread or flange interface.

[0031] See Figure 1 , Figure 2 Each set of teeth of a gear 40 is embedded with a permanent magnet. The upper cover 20 has a mounting slot for a rotation sensor. When the gear 40 rotates, the rotating magnetic field generated by the permanent magnet is detected by the rotation sensor. By calculating the number of pulses per unit time, the precise rotation speed of the gear 40 can be obtained, and then the instantaneous flow rate can be calculated. The total number of cumulative pulses corresponds to the cumulative flow rate.

[0032] Example 2, a micro gear 40 flow meter:

[0033] See Figure 2 Both sets of gears 40 are integrally machined, so that the teeth, shaft and top truncated cone protrusion 41 of the gear 40 are completed in one piece of raw material through precision machining, avoiding the errors and poor connection strength caused by separate assembly, and effectively improving the precision and strength of the gear 40.

[0034] See Figure 4The bottom wall of the upper cover 20 is provided with a receiving inlet cavity 22 and a receiving outlet cavity 23. The receiving inlet cavity 22 is directly above the inlet area 31, and the receiving outlet cavity 23 is directly above the outlet area 32. The receiving inlet cavity 22 and the receiving outlet cavity 23 serve as buffer areas for the medium fluid. Before the fluid enters and leaves the meshing area of ​​the gear 40, they effectively absorb pressure pulsations, making the flow field more uniform and stable, thereby reducing measurement errors caused by flow field disturbances and improving the signal-to-noise ratio of the output signal.

[0035] See Figure 3 The top wall of the bottom shell 10 is provided with a primary receiving groove 11 and a secondary receiving groove 12 for placing the primary sealing ring 13 and the secondary sealing ring 14 respectively. The primary receiving groove 11 and the secondary receiving groove 12 provide precise installation positions for the primary sealing ring 13 and the secondary sealing ring 14. A transverse ring 131 is connected to the inner side of the primary sealing ring 13. The transverse ring 131 is located outside the primary receiving groove 11 and is in contact with the top wall of the bottom shell 10 and the bottom wall of the upper cover 20. The transverse ring 131 has a groove 132 facing the measuring cavity 30. The groove 132 is a U-shaped groove. The transverse ring 131 is pressed tightly by the simultaneous close contact of the top wall of the bottom shell 10 and the bottom wall of the upper cover 20. The groove 132 generates a self-tightening sealing effect through the fluid pressure in the measuring cavity 30. The higher the pressure, the tighter the seal, effectively enhancing the overall sealing reliability of the flow meter and preventing external leakage under high pressure or complex working conditions.

[0036] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A miniature gear flow meter, characterized in that, The device includes a housing, and the housing has a measuring cavity inside. The measuring cavity is provided with two sets of meshing gears. The measuring cavity has an inlet area and an outlet area at the opposite ends of the two sets of gears, respectively. Each set of gears has a frustum protrusion on its top, and the outer surface of each set of gears is covered with a wear-resistant coating. The housing includes a combined bottom shell and a top cover. The bottom shell has a medium inlet group that communicates with the inlet area and a medium outlet group that communicates with the outlet area. The bottom wall of the top cover is provided with two sets of grooves, and the two sets of grooves are respectively for the two sets of frustum protrusions to be inserted into and form a stepped fit. At the joint surface between the bottom shell and the top cover, a primary sealing ring and a secondary sealing ring are distributed sequentially from the inside to the outside.

2. The micro gear flow meter according to claim 1, characterized in that, Both sets of gears are machined as a single piece.

3. The micro gear flow meter according to claim 1, characterized in that, The wear-resistant coating is a diamond-like carbon coating or a tungsten carbide coating.

4. The micro gear flow meter according to claim 1, characterized in that, The bottom shell and the top cover are joined together by multiple sets of bolt assemblies to form the measuring cavity.

5. The micro gear flow meter according to claim 1, characterized in that, The medium inlet group includes a medium inlet cross channel and a medium inlet vertical channel, and the medium outlet group includes a medium outlet cross channel and a medium outlet vertical channel.

6. The micro gear flow meter according to claim 5, characterized in that, The bottom wall of the upper cover is provided with an inlet cavity and an outlet cavity, the inlet cavity being directly above the inlet area and the outlet cavity being directly above the outlet area.

7. The micro gear flow meter according to claim 1, characterized in that, The top wall of the bottom shell is provided with a primary groove and a secondary groove for placing the primary sealing ring and the secondary sealing ring, respectively.

8. The micro gear flow meter according to claim 7, characterized in that, A transverse ring is connected to the inner side of the primary sealing ring. The transverse ring is located outside the primary receiving groove and is in contact with the top wall of the bottom shell and the bottom wall of the upper cover. The transverse ring has a groove facing the measuring cavity.

Images