Coriolis flowmeter

Abstract

The utility model provides a Coriolis flowmeter which is characterized in that the upstream end and the downstream end of a flow guide pipe in a chamber of a meter shell are respectively connected with an opening and closing valve and a liquid outlet pipe, and a sensing device is arranged close to the free end of a vibration rod in the flow guide pipe; the middle section or one end of the vibration rod is hinged, a magnet block is arranged at one end away from the sensing device, and a magnetic induction coil is arranged on the pipe wall, close to the flow guide pipe, of the magnet block. According to the Coriolis flowmeter, the magnet block and the magnetic induction coil are arranged at the end, away from the sensing device, of the vibration rod, so that when the vibration rod vibrates, the magnet block swings along with rotation of the hinged position of the vibration rod and cuts the magnetic induction line of the magnetic induction coil to generate electricity, and the Coriolis flowmeter can automatically supply energy in the measuring process.

Description

Technical Field

[0001] The utility model relates to the technical field of fluid measurement, in particular to a Coriolis flowmeter. Background Art

[0002] A flow meter is an instrument used to measure the flow rate of a fluid in a pipeline. A flow meter designed using the Coriolis force principle has the advantages of being able to directly measure the flow rate and having high measurement accuracy. The Coriolis flow meter in the prior art is usually designed as a measuring tube with an electromagnetic vibrator and two vibration sensors, which measures the vibration signal when the fluid passes through the measuring tube to feedback its flow rate.

[0003] The patent named "Fluid Oscillation Flowmeter" (US3698245A) discloses a technical solution, in which a reed assembly 17 is provided in the flow channel 16. When the fluid passes through the flow channel, the reed assembly 17 generates elastic oscillations, and the sensor responds to the output, thereby calculating the flow rate of the fluid. However, the flowmeter in the above solution needs an external power supply for measurement when applied to a Coriolis flowmeter, which is not convenient for application in places where it is difficult to provide power. Utility Model Content

[0004] The utility model aims to provide a Coriolis flowmeter, which uses its own measuring structure to set a self-generating module, thereby improving the convenience of using the Coriolis flowmeter.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a Coriolis flowmeter, the downstream end of the liquid inlet pipe is connected to the inner cavity of a tube box-shaped case, a flow guide pipe is arranged in the case chamber, the downstream end of the flow guide pipe is connected to the liquid outlet pipe, a valve plate of an opening and closing valve is arranged at the pipe mouth of the upstream end of the liquid outlet pipe, and when the valve plate is displaced, the chamber of the case and the upstream end of the flow guide pipe are cut off or connected, a vibration rod is arranged in the flow guide pipe, a sensing device is arranged on the shell wall of the case near the free end of the vibration rod, a vibration signal of the vibration rod is collected and the collected vibration signal is output; a bracket connected to the pipe wall is arranged in the flow guide pipe, the middle section of the vibration rod or one end of the vibration rod is hinged on the bracket, a magnet block is arranged at the end of the vibration rod away from the sensing device, and a magnetic induction coil is arranged on the pipe wall of the flow guide pipe near the magnet block.

[0006] The utility model mainly arranges a flow guide tube in a case chamber, a vibration rod with one end hinged on a bracket is arranged in the flow guide tube, a magnet block is arranged at the end of the vibration rod away from the sensor device, and a magnetic induction coil is arranged on the tube wall of the flow guide tube near the magnet block, so that whenever the vibration rod is affected by the fluid in the flow guide tube and vibrates, the magnet block fixed on the end of the vibration rod away from the sensor device also swings with the rotation of the hinge of the vibration rod, and the magnet block cuts the magnetic induction line of the magnetic induction coil when swinging to generate electricity, so that the Coriolis flowmeter can power itself during the measurement process. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a schematic diagram of a Coriolis flowmeter case;

[0008] Figure 2 is a cross-sectional view of a Coriolis flowmeter;

[0009] Figure 3 Schematic diagram of the hinged end of the vibrating rod after removing the case of the Coriolis flowmeter. DETAILED DESCRIPTION

[0010] See also Figure 1 In the Coriolis flowmeter shown, the downstream end of the liquid inlet pipe 1 is connected to the inner cavity of the tube box-shaped case 3, a flow guide pipe 22 is arranged in the chamber of the case 3, the downstream end of the flow guide pipe 22 is connected to the liquid outlet pipe 2, a valve plate 211 of an opening and closing valve 21 is arranged at the pipe mouth of the upstream end of the liquid outlet pipe 2, and the valve plate 211 is displaced to cut off or connect the chamber of the case 3 and the upstream end of the flow guide pipe 22, a vibration rod 30 is arranged in the flow guide pipe 22, a sensor device 40 is arranged on the shell wall of the case 3 near the free end of the vibration rod 30, and the vibration signal of the vibration rod 30 is collected and outputted; a bracket connected to the pipe wall is arranged in the flow guide pipe 22, the middle section of the vibration rod 30 or one end of the vibration rod 30 is hinged on the bracket, a magnet block 50 is arranged at the end of the vibration rod 30 away from the sensor device 40, and a magnetic induction coil 51 is arranged on the pipe wall of the flow guide pipe 22 near the magnet block 50.

[0011] In the above scheme, a spring 5 is provided in the cavity of the opening and closing valve 21, and the valve plate 211 is a rubber sheet pre-stressed by the spring 5 and sealing the upstream end of the liquid outlet pipe 2. The pre-stressed pressure of the spring 5 can be adjusted and set on the opening and closing valve 21. Preferably, the opening and closing valve 21 can adopt a pilot valve, and the opening or closing of the opening and closing valve 21 is controlled by other control mechanisms. The vibration rod 30 in the guide tube 22 can be fixed at one end and freely suspended at the other end. The vibration rod 30 can be made of elastic materials, such as stainless steel sheets, phosphor copper sheets and plastic sheets, and the free end of the vibration rod 30 vibrates when the fluid passes through. If one end of the vibration rod 30 is hinged, the magnet block 50 is arranged at the hinged end and swings with the rotation of the hinged end of the vibration rod 30. If the vibration rod 30 is hinged in the middle section, the magnet block 50 is arranged at the free end away from the sensor device 40, and when the vibration rod 30 vibrates, the magnet block 50 swings accordingly. In the above two embodiments, the magnet block 50 cuts the magnetic induction lines of the magnetic induction coil when swinging, thereby generating current to charge the capacitor and battery in the Coriolis flowmeter. The processor of the Coriolis flowmeter controls and supplies power to other modules, so that the Coriolis flowmeter can power itself during the measurement process, thereby improving the convenience of use.

[0012] In order to improve the range ratio of the Coriolis flowmeter, a pulse ejector 11 is arranged on the tube wall of the flow guide tube 22, and the air inlet end of the pulse ejector 11 is connected to the chamber of the case 3, and the jet of the pulse ejector 11 is directed to the free end or segment of the vibration rod 30. In the above scheme, after the fluid enters from the liquid inlet pipe 1, it is divided into two paths at its downstream end, one path goes along the inner cavity of the tube box-shaped case 3 to reach the valve plate 211 of the opening and closing valve 21, and the other path enters the inner cavity of the case 3 from the air inlet end of the pulse ejector 11 on the tube wall. There are two possible situations here:

[0013] 1. When the fluid flow is small, the fluid pressure is small, and the fluid pressure flowing from the inner cavity of the case 3 to the valve plate 211 is not enough to open the valve plate 211. The fluid can only enter the downstream end of the inner cavity of the flow guide tube 22 from the pulse ejector 11 on the wall of the flow guide tube 22, and flow out from the liquid outlet pipe 2. Since the jet of the pulse ejector 11 points to the free end or segment of the vibration rod 30, the free end of the vibration rod 30 will vibrate under the impact of the jet. After the sensor device 40 collects the vibration signal of the vibration rod 30, the processor collects the vibration signal and processes it through the corresponding algorithm to obtain the flow rate of the fluid.

[0014] Second, when the fluid flow rate is large, the fluid pressure flowing from the inner cavity of the case 3 to the valve plate 211 is sufficient to open the valve plate 211, and the fluid enters the guide tube 22 through the on-off valve 21, forming a vortex in the guide tube 22 to vibrate the vibration rod 30. In this process, part of the fluid still enters through the liquid inlet 111 of the pulse ejector 11, and the two fluids merge at the downstream end of the guide tube 22 and flow out from the liquid outlet pipe 2. At this time, the measurement of the flow meter is based on the Coriolis force principle. The vortex in the guide tube 22 and the jet of the pulse ejector 11 merge and act on the vibration rod 30 to produce resonance. The sensor device 40 collects the vibration signal synthesized by the above two vibrations. The vibration signal obtains the magnitude of the Coriolis force generated by the fluid through the corresponding algorithm, and then measures the flow rate.

[0015] Therefore, the Coriolis flowmeter of the present solution can measure under the above two flow conditions, and can measure fluids with large flow rates as well as fluids with small flow rates, both of which have high measurement accuracy. Compared with traditional flowmeters, the Coriolis flowmeter of the present solution obviously has a larger range ratio. In the present invention, when the flowmeter measures different fluid media, it can select corresponding vibration rods 30 with different Young's moduli according to media with different densities. For example, when measuring water flow and air flow with similar flow rates, the Young's modulus of the vibration rod 30 used to measure the water flow is greater than the Young's modulus of the vibration rod 30 used to measure the air flow.

[0016] The outer surface of the tube wall at the downstream end of the flow guide tube 22 is connected with a partition 8 that separates the liquid inlet tube 1 and the liquid outlet tube 2. The partition 8 is annular as a whole and is obliquely placed in the chamber of the watch case 3 so that the liquid outlet tube 2 is only connected to the downstream end of the flow guide tube 22. The outer edge of the partition 8 abuts against the inner wall of the watch case 3 and a groove for accommodating a sealing ring is provided on the outer edge of the partition 8.

[0017] In order to obtain the vibration signal of the vibration rod 30 more accurately, the vibration rod 30 is in a strip shape, and the length direction of the vibration rod 30 is consistent with the core line direction of the guide tube 22.

[0018] Preferably, the rod core line of the vibration rod 30 coincides with the tube core line of the guide tube 22. The midstream section of the guide tube 22 is provided with a reduced diameter section 221, and the middle section of the vibration rod 30 is located in the reduced diameter section 221. In the above scheme, the strip-shaped vibration rod 30 has a larger force-bearing area during the oscillation of the fluid, which is conducive to the vibration of the free end of the vibration rod 30. The rod core line of the vibration rod 30 coincides with the tube core line of the guide tube 22, so that the tube cavities on both sides of the vibration rod 30 are symmetrical. After the fluid passes through the reduced diameter section 221 in the guide tube 22, the vortex oscillation generated by the fluid is more intense, which is convenient for the sensor device 40 to collect vibration signals.

[0019] As a preferred embodiment, the sensor device 40 includes a magnet 401 fixed at the free end of the vibration rod 30 and a Wiegand sensor 402 arranged adjacent to the magnet 401. The Wiegand sensor 402 is fixed on the shell wall of the watch case 3 at the downstream end of the guide tube 22. The Wiegand sensor 402 has the advantages of not requiring an external power supply and accurate measurement. The vibration signal can be measured by using the magnet 401 in combination with the Wiegand sensor 402, and high-precision measurement of large and small flows can be achieved through algorithms. It should be noted that the sensor device 40 of the present invention is not limited to the above-mentioned embodiment. The sensor device 40 may also use an angular velocity sensor, a Hall sensor, or other sensors that collect vibration signals using laser measurement, electrical measurement, or the like.

[0020] The flow meter of the present invention can be used on a water meter or a gas meter. Preferably, an independent shell that can accommodate the electronic components of the smart water meter or gas meter is attached to the outside of the shell of the opening and closing valve 21. The shell is provided with a liquid crystal display device such as an LCD display to indicate water usage information such as the operating status of the water meter or gas meter, and a communication device for providing information to a remote management system is provided in the cavity of the shell.

[0021] When used as a smart water meter, the signal lines of the vibrating rod 30 and the sensor device 40 of the present invention are connected to the electronic circuit, and the working status of the vibrating rod 30 and the sensor device 40, and the information of the water flow flowing through the water meter can be monitored by electronic components. Through the control of the electronic circuit, the sensor device and the built-in operating software, the information such as the water flow speed and flow rate in the pipeline, whether the pipeline is leaking, whether the pipeline is overloaded, whether the water meter is working, etc. can be collected and displayed on the liquid crystal display, and provided to the remote meter reading system through wired or wireless communication.

Claims

1. A Coriolis flowmeter, characterized in that: The downstream end of the liquid inlet pipe (1) is connected to the inner cavity of a tube box-shaped case (3); a flow guide pipe (22) is arranged in the chamber of the case (3); the downstream end of the flow guide pipe (22) is connected to the liquid outlet pipe (2); a valve plate (211) of an opening and closing valve (21) is arranged at the pipe mouth of the upstream end of the liquid outlet pipe (2); when the valve plate (211) is displaced, the chamber of the case (3) and the upstream end of the flow guide pipe (22) are cut off or connected; a vibration rod (30) is arranged in the flow guide pipe (22); a sensor device (40) is arranged on the shell wall of the case (3) near the free end of the vibration rod (30); the sensor device (40) collects vibration signals of the vibration rod (30) and outputs the collected vibration signals; A bracket connected to the pipe wall is provided in the flow guide pipe (22); the middle section of the vibration rod (30) or one end of the vibration rod (30) is hinged on the bracket; a magnet block (50) is arranged at one end of the vibration rod (30) away from the sensor device (40); and a magnetic induction coil (51) is provided on the pipe wall of the flow guide pipe (22) adjacent to the magnet block (50).

2. The Coriolis flowmeter according to claim 1, characterized in that: A pulse jet (11) is arranged on the tube wall of the flow guide tube (22), the air inlet end of the pulse jet (11) is connected to the chamber of the watch case (3), and the jet of the pulse jet (11) is directed to the free end or section of the vibration rod (30).

3. The Coriolis flowmeter according to claim 2, characterized in that: The vibration rod (30) is in the shape of a strip, and the length direction of the vibration rod (30) is consistent with the direction of the core line of the flow guide tube (22).

4. The Coriolis flowmeter according to claim 3, characterized in that: The midstream section of the flow guide pipe (22) is provided with a reduced diameter section (221), and the middle section of the vibration rod (30) is located in the reduced diameter section (221).

5. The Coriolis flowmeter according to claim 3, characterized in that: The rod core line of the vibration rod (30) coincides with the tube core line of the flow guide tube (22).

6. The Coriolis flowmeter according to claim 1, characterized in that: The sensing device (40) comprises a magnet (401) fixed at the free end of the vibration rod (30) and a Wiegand sensor (402) arranged adjacent to the magnet (401); the Wiegand sensor (402) is fixed on the shell wall of the meter shell (3) at the downstream end of the flow guide tube (22).

Images