A self-powered flow meter

Abstract

This invention relates to a self-powered flow meter, belonging to the field of new energy technology and flow meters. It mainly consists of a housing, impeller, coil, generating magnet, bracket, drive magnet, and circuit board. The housing has a transducer chamber and an excitation chamber separated by a housing partition. A half-shaft is located on the lower surface of the housing partition, and the excitation chamber has an inlet and outlet on its side wall. The bracket has a stepped cavity above it and wire frames with wire frame cavities evenly distributed below it. The impeller has blades on its outer edge, and drive magnets are evenly distributed on the impeller. The impeller is mounted on the half-shaft, and the drive magnets are close to the housing partition. A top cover is installed at the ends of the transducer chamber and the excitation chamber, respectively, and a top cover presses the bracket into the transducer chamber. A coil is sleeved on the wire frame, and a generating magnet, which is a sphere or cone, is installed in the wire frame cavity. When the fluid drives the impeller to rotate, the drive magnet applies a rotational torque to the generating magnet, causing the generating magnet to roll. The coil cuts magnetic lines of force to generate electricity, which is supplied to the control unit and sensor. The transmitting unit transmits the flow information.

Description

Technical Field

[0001] This invention belongs to the field of new energy and flow meter technology, specifically relating to a self-powered flow meter for driving and remote data transmission of residential gas and tap water flow meters. Background Technology

[0002] Tap water and gas are indispensable consumer goods in the daily lives of urban residents, and their consumption records and statistics are currently mainly done manually. Manual meter reading is not only inefficient and wasteful of manpower and resources, but more importantly, meter readers often have to make multiple unsuccessful trips to residents' homes, severely impacting the accuracy and real-time nature of data statistics. Therefore, people have begun to develop remote automatic meter reading systems for tap water and gas, which have been applied in newly built residential buildings. Although the data processing and transmission technologies of existing meter reading systems are quite mature, it is still difficult to promote their application in older residential areas. One reason is that the power supply problem has not been well resolved, and it is inconvenient to pre-lay cables for automatic meter reading systems in older residential buildings. Therefore, people are trying to develop a flow meter that can be powered by electricity. Currently, various forms of piezoelectric and electromagnetic self-powered gas and water meters have been developed, but their drawback is that their power generation capacity is weak and cannot meet the driving and data transmission requirements of the flow meter at low speeds. Therefore, there is an urgent need to develop a self-powered flow meter with stronger power generation capacity. Summary of the Invention

[0003] The self-powered flow meter of the present invention comprises a housing, an impeller, a top cover, a bottom cover, a coil, a generating magnet, a bracket, a driving magnet, a circuit board, a bearing, a sensor, a retaining ring, and a baffle. The electronic control unit on the circuit board includes energy harvesting, energy management, energy storage, and information transmission units. The sensor is a dedicated flow sensor, or it can be a sensing coil with only the coupling effect of the driving magnet, that is, the voltage signal generated by the sensing coil cutting the magnetic lines of force of the driving magnet is used as the basis for flow measurement.

[0004] The casing has a transducer cavity and an excitation cavity separated by a shell partition. The shell partition is the bottom wall of the transducer cavity and the top wall of the excitation cavity. A sensor is installed on the top of the shell partition and a half-shaft is installed on the bottom. The sensor is located in the transducer cavity and the half-shaft is located in the excitation cavity. The sensor is an electromagnetic sensor or a piezoelectric sensor with a ferromagnetic substrate, used to measure the impeller speed. The side wall of the excitation cavity has an inlet and an outlet, which are coaxial.

[0005] The bracket has a stepped cavity above the frame plate and wire frames with wire frame cavities evenly distributed below. The ends of the wire frame cavities face downwards, and the frame plate is the top wall of the wire frame cavity.

[0006] The impeller has blades on its outer edge and driving magnets evenly distributed on the disc. The driving magnets are evenly embedded in the side of the disc along the circumferential direction. The driving magnets can be cylindrical, square, rectangular, or arc-shaped, that is, the cross-sectional shape of the driving magnets can be circular, square, rectangular, or arc-shaped. The magnetic poles of the driving magnets are distributed along the axial or circumferential direction of the disc. The driving magnets with magnetic poles distributed along the axial direction of the disc are called axial driving magnets, and the driving magnets with magnetic poles distributed along the circumferential direction of the disc are called circumferential driving magnets. The magnetic poles of two adjacent axial driving magnets in the circumferential direction are arranged in opposite directions, and the magnetic poles of two adjacent circumferential driving magnets in the circumferential direction are arranged in the same direction.

[0007] The top cover is screwed to the end of the side wall of the transducer cavity, and the top cover presses the bracket into the transducer cavity; the circuit board is screwed to the stepped cavity above the bracket, the bracket's frame plate is screwed to the top cover, and the end of the wire frame abuts against the shell partition plate.

[0008] A coil is fitted onto a wire frame, and a generating magnet is installed inside the wire frame cavity. The generating magnet is located inside the coil, and the wire frame separates the generating magnet from the coil. The generating magnet is either a sphere or a cone, and it is magnetized radially. The magnetic poles of the generating magnet are distributed radially. When the generating magnet is a cone, its axis is perpendicular to the coil axis. The coil and the generating magnet inside it constitute a transducer. There is no interaction force between the generating magnets in two adjacent transducers in the two circumferential directions. The number of generating magnets and driving magnets is equal or unequal, and the distances from the generating magnets and driving magnets to the half-axis are equal, that is, the distances from the geometric centers of the generating magnets and driving magnets to the center of the half-axis are equal.

[0009] The bottom cover is installed on the side wall end of the excitation chamber by screws, and a sealing gasket is provided between the bottom cover and the side wall of the excitation chamber.

[0010] The impeller is mounted on the half shaft via bearings and can rotate freely around the half shaft. The shaft hole of the impeller is fitted onto the half shaft and positioned by a retaining ring and a baffle. The retaining ring is mounted on the impeller with screws and presses the outer ring of the bearing onto the limiting ring of the impeller. The baffle is mounted on the end of the half shaft with screws and presses the inner ring of the bearing onto the shoulder of the half shaft. The drive magnet approaches the shell partition.

[0011] In this invention, the housing, impeller, and bracket are all made of non-ferromagnetic materials, including stainless steel, aluminum alloys, and other metals or polymer plastics.

[0012] When fluid flows through the transducer cavity, the fluid drives the impeller and the driving magnet to rotate. An alternating force of varying magnitude is generated between the driving magnet and the generating magnet. The force between the driving magnet and the generating magnet is an attractive force. As the driving magnet gradually approaches and moves away from the generating magnet, it applies a rotational torque to the generating magnet. Under the action of the rotational torque, the generating magnet rolls within the wire frame cavity. The magnetic poles of the generating magnet and the magnetic field strength passing through the coil change alternately. The coil cuts the magnetic lines of force and converts mechanical energy into electrical energy. The generated electrical energy is transmitted to the circuit board through wires. After conversion and processing, the electrical energy is stored or output. The sensor determines the impeller speed by sensing the change in the magnetic field strength of the driving magnet on the impeller and further converts it into fluid flow rate. The transmitting unit on the circuit board transmits the flow rate information obtained by the sensor.

[0013] In this invention, to obtain better power generation capability, the parameter relationship between the coil and the generating magnet is as follows: λ=L / D=2±1, δ=T / D=0.6±0.4, η=V / D=2.25±0.75, β=U / D=1.3±0.7, where D is the diameter of the spherical generating magnet and the average diameter of the conical generating magnet, L is the length of the conical generating magnet, and T, V and U are the wall thickness, radial width and height of the coil, respectively. The radial width of the coil refers to the width of the coil along the radial direction of the generating magnet.

[0014] Existing electromagnetic power generation utilizes a coil cutting the magnetic field lines of a moving magnet located outside the coil to generate electricity. Unlike these methods, the generator of this invention uses a driving magnet to force a generating magnet inside the coil to roll, thereby changing the direction and intensity of the generating magnet's magnetic field. The coil cuts the magnetic field lines to generate electricity, and the gradient of the magnetic field intensity change generated by the driving magnet is relatively small. The function of the driving magnet is to drive the generating magnet to rotate and provide an electromagnetic signal to the sensor for flow measurement. During the rolling of the generating magnet inside the coil, the gradient of the magnetic field change caused by the change of magnetic poles is large, and the generating magnet rolls multiple times and the coil cuts the magnetic field lines multiple times with each excitation. Therefore, the power generation capacity is strong, the output voltage is high, and the amount of electricity is large.

[0015] Advantages and features: The power generation unit does not require a speed-increasing mechanism, and its structure and driving process are simple. It increases the gradient of magnetic field strength by changing the direction of the magnetic poles of the generating magnets in the coil. A single excitation can achieve multiple cutting of magnetic lines of force to generate electricity, resulting in a large power output and high output voltage. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a self-powered flowmeter with a conical generator magnet in a preferred embodiment of the present invention; Figure 2 yes Figure 1 AA section view; Figure 3 This is a schematic diagram of the casing structure in a preferred embodiment of the present invention; Figure 4 This is a schematic diagram of the bracket structure in a preferred embodiment of the present invention; Figure 5 yes Figure 4 A bottom view; Figure 6 This is a schematic diagram of an impeller structure equipped with an axial drive magnet in a preferred embodiment of the present invention; Figure 7 yes Figure 6 Top view; Figure 8 This is a schematic diagram of an impeller structure equipped with a circumferential driving magnet in a preferred embodiment of the present invention; Figure 9 yes Figure 8 Top view; Figure 10 This is a schematic diagram of the structure of a self-powered flowmeter with a spherical generating magnet in a preferred embodiment of the present invention. Detailed Implementation

[0017] The self-powered flow meter of the present invention comprises a housing a, an impeller c, a top cover h, a bottom cover b, a coil x, a generating magnet y, a bracket z, a driving magnet g, a circuit board p, a bearing f, a sensor u, a retaining ring d, and a baffle e. The electronic control unit on the circuit board p includes energy harvesting, energy management, energy storage, and information transmission units. The sensor u is a dedicated flow sensor, or the sensor u can be a sensing coil with only the coupling effect of the driving magnet g, that is, the voltage signal generated by the sensing coil cutting the magnetic lines of force of the driving magnet g is used as the basis for flow measurement.

[0018] The housing a has a transducer cavity a2 and an excitation cavity a3 separated by a housing partition a1. The housing partition a1 is the bottom wall of the transducer cavity a2 and the top wall of the excitation cavity a3. A sensor u is installed above the housing partition a1 and a half shaft a4 is installed below it. The sensor u is located in the transducer cavity a2 and the half shaft a4 is located in the excitation cavity a3. The sensor u is an electromagnetic sensor or a piezoelectric sensor with a ferromagnetic substrate, such as a nickel substrate piezoelectric vibrator, used to measure the impeller speed. The side wall of the excitation cavity a3 has an inlet a5 and an outlet a6, which are coaxial.

[0019] The bracket z has a stepped cavity z2 above the frame plate z1, and wire frames z3 with wire frame cavities z4 are evenly distributed below it. The port of the wire frame cavity z4 faces downward, and the frame plate z1 is the top wall of the wire frame cavity z4.

[0020] The impeller c has blades c2 on the outer edge of the disk c1. Drive magnets g are evenly distributed on the disk c1. The drive magnets g are evenly embedded in the side of the disk c1 along the circumferential direction. The cross-sectional shape of the drive magnets g is circular, square, rectangular, or arc-shaped. The magnetic poles of the drive magnets g are distributed along the axial or circumferential direction of the disk c1. The drive magnets g with magnetic poles distributed along the axial direction of the disk c1 are called axial drive magnets g, and the drive magnets g with magnetic poles distributed along the circumferential direction of the disk c1 are called circumferential drive magnets g. The magnetic poles of two adjacent axial drive magnets g in the circumferential direction are arranged in opposite directions, and the magnetic poles of two adjacent circumferential drive magnets g in the circumferential direction are arranged in the same direction.

[0021] The top cover h is installed on the side wall end of the transducer cavity a2 by screws, and the top cover h presses the bracket z into the transducer cavity a2; the circuit board is installed in the stepped cavity z2 above the bracket z by screws, the bracket plate z1 of the bracket z is installed on the top cover h by screws, and the end of the wire frame z3 abuts against the shell partition a1.

[0022] A coil x is fitted on a wire frame z3, and a generating magnet y is installed in the wire frame cavity z4. The generating magnet y is located inside the coil x, and the wire frame z3 separates the generating magnet y from the coil x. The generating magnet y is a sphere or a cone, and it is magnetized radially. The magnetic poles of the generating magnet y are distributed radially. When the generating magnet y is a cone, its axis t is perpendicular to the axis s of the coil x. The coil x and the generating magnet y inside it constitute a transducer. There is no interaction force between the generating magnets y in two adjacent transducers in the two circumferential directions. The number of generating magnets y and driving magnets g are equal or unequal. The distances of the generating magnets y and driving magnets g from the half-axis a4 are equal, that is, the distances from the geometric centers of the generating magnets y and driving magnets g to the center of the half-axis a4 are equal.

[0023] The bottom cover b is installed on the side wall end of the excitation chamber a3 by screws, and a sealing gasket is provided between the bottom cover b and the side wall of the excitation chamber a3.

[0024] Impeller c is mounted on half shaft a4 via bearing f and can rotate freely around half shaft a4. The shaft hole of wheel disc c1 is fitted onto half shaft a4 and positioned by retaining ring d and baffle e. Retaining ring d is mounted on wheel disc c1 with screws and presses the outer ring of bearing f onto the limiting ring c3 of wheel disc c1. Baffle e is mounted on the end of half shaft a4 with screws and presses the inner ring of bearing f onto the shoulder of half shaft a4. Drive magnet g approaches shell partition a1.

[0025] In this invention, the housing a, impeller c, and bracket z are all made of non-ferromagnetic materials, including stainless steel, aluminum alloy, and other metals or polymer plastics.

[0026] When fluid flows through the transducer cavity a2, the fluid drives the impeller c and the driving magnet g to rotate. The driving magnet g and the generating magnet y generate an alternating force. The force between the driving magnet g and the generating magnet y is an attractive force. As the driving magnet g gradually approaches and moves away from the generating magnet y, it applies a rotational torque to the generating magnet y. After being subjected to the rotational torque, the generating magnet y rolls in the wire frame cavity z4. The magnetic poles of the generating magnet y and the magnetic field strength passing through the coil x change alternately. The coil x cuts the magnetic lines of force and converts mechanical energy into electrical energy. The generated electrical energy is transmitted to the circuit board p through wires. After conversion and processing, the electrical energy is stored or output. The sensor u determines the rotational speed of the impeller z by sensing the change in the magnetic field strength of the driving magnet g on the impeller z and further converts it into fluid flow rate. The transmitting unit on the circuit board p transmits the flow rate information obtained by the sensor u.

[0027] In this invention, to obtain better power generation capability, the parameter relationship between coil x and generating magnet y is as follows: λ=L / D=2±1, δ=T / D=0.6±0.4, η=V / D=2.25±0.75, β=U / D=1.3±0.7, where D is the diameter of spherical generating magnet y and the average diameter of conical generating magnet y, L is the length of conical generating magnet y, T, V and U are the wall thickness, radial width and height of coil x, respectively, and the radial width of coil x refers to the width of coil x along the radial direction of generating magnet y.

[0028] Existing electromagnetic power generation utilizes a coil cutting the magnetic field lines of a moving magnet located outside the coil to generate electricity. In contrast, the self-powered flowmeter of this invention uses a driving magnet g to force the generating magnet y inside the coil x to roll, thereby changing the direction and intensity of the magnetic field of the generating magnet y. The coil x cuts the magnetic field lines to generate electricity, and the gradient of the magnetic field intensity change generated by the driving magnet g is relatively small. The function of the driving magnet g is to drive the generating magnet y to rotate and provide an electromagnetic signal to the sensor u for flow measurement. During the rolling process of the generating magnet y inside the coil x, the gradient of the magnetic field change caused by the change in magnetic poles within the coil x is large, and with each excitation, the generating magnet y rolls multiple times, and the coil x cuts the magnetic field lines multiple times. Therefore, it has strong power generation capacity, high output voltage, and large power output.

Claims

1. A self-powered flowmeter, mainly composed of a casing, an impeller, a coil, a power generation magnet, a bracket, a driving magnet, a circuit board and a sensor, the casing, the impeller and the bracket are made of non-ferromagnetic material; the casing is provided with a transducer cavity and an excitation cavity separated by a casing partition, the sensor is installed above the casing partition, a half shaft is arranged below the casing partition, an inlet and an outlet are arranged on the side wall of the excitation cavity; a stepped cavity is arranged above the bracket plate of the bracket, wire holders with wire holder cavities are uniformly arranged below the bracket plate, the ports of the wire holder cavities face downward; blades are arranged on the outer edge of the disc of the impeller, driving magnets are uniformly arranged on the disc, the impeller is installed on the half shaft and can rotate freely around the half shaft, the driving magnets are close to the casing partition; the magnetic poles of the driving magnets are distributed along the axial direction or the circumferential direction of the disc, the directions of the magnetic poles of two adjacent axial driving magnets are opposite, the directions of the magnetic poles of circumferential driving magnets are the same; a top cover and a bottom cover are respectively installed at the ends of the transducer cavity and the excitation cavity, the top cover press-bonds the bracket in the transducer cavity; characterized in that: A coil is mounted on a wire frame, and a generating magnet is installed inside the wire frame cavity. The generating magnet is located inside the coil, and the wire frame separates the generating magnet from the coil. The generating magnet is either a sphere or a cone, with its magnetic poles distributed radially. When the generating magnet is a cone, its axis is perpendicular to the coil axis. The parameter relationship between the coil and the generating magnet is: L / D=2±1, T / D=0.6±0.4, V / D=2.25±0.75, β=U / D=1.3±0.7, where D is the diameter of the spherical generating magnet and the average diameter of the conical generating magnet, L is the length of the conical generating magnet, and T, V, and U are the wall thickness, radial width, and height of the coil, respectively. The radial width of the coil refers to the width of the coil along the radial direction of the generating magnet. When the fluid drives the impeller to rotate, the driving magnet applies a rotational torque to the generating magnet. The generating magnet rolls, and the strength of its magnetic poles and the magnetic field passing through the coil changes alternately. The coil cuts the magnetic lines of force to generate electricity and supplies it to the transmitting unit. The transmitting unit transmits the flow information obtained by the sensor.

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