CN210570855U

CN210570855U - Piston type flowmeter

Info

Publication number: CN210570855U
Application number: CN201921072577.8U
Authority: CN
Inventors: 向德华; 李宁; 周艳; 徐旷宇
Original assignee: Hunan Institute of Metrology and Test
Current assignee: Hunan Institute of Metrology and Test
Priority date: 2019-07-10
Filing date: 2019-07-10
Publication date: 2020-05-19
Anticipated expiration: 2029-07-10

Abstract

The utility model discloses a piston flowmeter relates to fluid flow's measurement area. The piston type flowmeter comprises a guide rod, a displacement sensor, at least two groups of pipelines, valves correspondingly arranged on the pipelines and a control module; the guide rod is arranged in the cylinder body and does not need to penetrate through a sealing cover at one end of the cylinder body, so that the problem of dynamic sealing caused by the guide rod is solved, the leakage accident is avoided, and the maintenance workload is reduced; fluid is controlled to enter or be discharged from the cylinder body by controlling the opening and closing of the corresponding valve, the motion pressure of the fluid drives the piston to move, and the piston can drive the guide rod to reciprocate along the displacement sensor, so that reciprocating bidirectional metering is realized, and the measuring working efficiency is improved; meanwhile, the fluid moves actively, the piston moves passively, and the structure of a driving motor, a screw rod assembly, a heavy base and the like is omitted, so that the structure is simple, the volume and the weight of the flowmeter are greatly reduced, and the flowmeter can be carried to the field for work.

Description

Piston type flowmeter

Technical Field

The utility model belongs to fluid flow's measurement field especially relates to a piston flowmeter.

Background

Flow measuring device can be very convenient the flow of measurement liquid, and the equipment of current flow measurement is various, and is different because of the principle is different, and specific has the device that drives the gear rotation through liquid flow and measures the flow, also has the flow that measures the fluid through the propagation velocity change of ultrasonic, and these flow measuring device all have its certain defect, and measurement accuracy is not accurate enough, and equipment structure is complicated, and is with high costs.

Although there is a piston type displacement flow measuring device, the guide rod on the piston of this type of flow measuring device must pass through the sealing cover at one end of the cylinder body, and the adopted displacement device is an external device such as a ball screw, and the guide rod drives the ball screw to move. The external displacement sensor has high requirement on the working environment, has small workload and can not work for a long time. Meanwhile, in the existing piston type displacement flow measuring device, the pistons are all active pistons and generally comprise a driving motor, a screw rod assembly, a cylinder body, a piston, a pipeline system, a signal generator and a computer control system. When the automatic fluid discharging device works, the motor drives the screw rod assembly to rotate, the piston is driven to do uniform linear motion along the axis of the cylinder body, fluid is discharged or sucked, the motion of the piston is active, and the motion of the fluid is passive. The active piston has a complex structure, a large volume and a large weight, and the body of the active piston needs to be placed on a heavy base, so that the weight of the device is further increased, and the active piston cannot be carried to work on site. The driving piston is generally of a one-way structure, namely, only one-way metering can be performed during working, reciprocating two-way metering cannot be performed, and the working efficiency is relatively low.

SUMMERY OF THE UTILITY MODEL

The utility model provides a piston flowmeter detects the position of piston in the cylinder body through built-in displacement sensor, again according to the switching of the position control of piston corresponding valve and realize that the piston uninterruptedly reciprocating motion is with continuous measurement.

The utility model discloses a solve above-mentioned technical problem through following technical scheme: a piston flow meter comprising:

the top of the cylinder body is provided with a guide groove, and the guide groove is communicated with the cylinder body;

a piston disposed within the cylinder;

the guide rod is arranged on the piston, is arranged in the cylinder body and/or the guide groove and is of an inner hollow structure;

one end of the displacement sensor is arranged at the top of the guide groove, and the other end of the displacement sensor extends to the inner hollow structure of the guide rod;

one end of each group of pipelines is communicated with the top of the cylinder body, and the other end of each group of pipelines is communicated with the bottom of the cylinder body;

a fluid inlet and outlet arranged on each group of pipelines; the fluid inlet and outlet are fluid inlets or fluid outlets;

at least one valve respectively arranged on pipelines at two sides of the fluid inlet and outlet;

and the control module is connected with the displacement sensor and the valve.

Furthermore, the displacement sensor adopts a magnetostrictive displacement sensor, a magnetic ring of the displacement sensor is arranged at the top of the guide rod, and a detection rod of the displacement sensor penetrates through the magnetic ring and extends to an inner hollow structure of the guide rod.

Furthermore, the pipelines comprise two groups, wherein the fluid inlet and the fluid outlet on one group of pipelines are fluid inlets, and the fluid inlet and the fluid outlet on the other group of pipelines are fluid outlets; the pipelines on the two sides of the fluid outlet are respectively provided with a first valve and a second valve, and the pipelines on the two sides of the fluid inlet are respectively provided with a third valve and a fourth valve.

Furthermore, the valve is an angle seat valve which has the characteristics of sensitive response and accurate action.

Further, the piston flowmeter also comprises a temperature sensor connected with the control module.

Further, the piston flow meter further comprises a timing module connected with the control module.

Furthermore, the piston comprises a piston body, and a first sealing ring, a first air bag, a second sealing ring, a second air bag and a third sealing ring which are sequentially arranged on the periphery of the piston body; the first air bag is communicated with the second air bag, and the outer diameters of the first air bag and the second air bag are smaller than the inner diameter of the cylinder body.

Further, the number of the first sealing ring, the second sealing ring and the third sealing ring is at least one.

Further, a groove is formed in the piston body between the first sealing ring and the third sealing ring and used for containing lubricating oil.

Further, the piston type flowmeter also comprises a turning support, and the turning support comprises a support base and an outer frame; the piston type flowmeter is fixedly arranged in the outer frame, and the outer frame is rotatably arranged on the bracket base.

The piston type flowmeter is fixed in the outer frame, and the outer frame is rotatably arranged on the support base, so that the piston type flowmeter can be turned over on the support base.

Furthermore, a positioning pin is arranged between the support base and the outer frame, and a caster is arranged on the outer frame.

The locating pin is used for supporting the fixed on the base when piston flowmeter does not overturn, prevents to swing on supporting the base. When not in work, the piston type flowmeter with the outer frame can be detached from the supporting base and pushed to move through the trundles, so that the flowmeter is convenient to carry.

Advantageous effects

Compared with the prior art, the piston type flowmeter of the utility model comprises a guide rod, a displacement sensor, at least two groups of pipelines, valves correspondingly arranged on the pipelines and a control module; the guide rod is arranged in the cylinder body and does not need to penetrate through a sealing cover at one end of the cylinder body, so that the problem of dynamic sealing caused by the guide rod is solved, the leakage accident is avoided, and the maintenance workload is reduced; the displacement sensor is adopted to measure the displacement of the piston, and the displacement sensor extends to the inner hollow structure of the guide rod, so that the piston can be detected at any position without deviating from the detection of the displacement sensor; the utility model controls the opening and closing of the corresponding valve to control the fluid to enter or discharge from the cylinder body, the motion pressure of the fluid drives the piston to move, and the piston can drive the guide rod to reciprocate along the displacement sensor, thereby realizing the reciprocating bidirectional metering and improving the measuring work efficiency; meanwhile, the fluid moves actively, the piston moves passively, and the structure of a driving motor, a screw rod assembly, a heavy base and the like is omitted, so that the structure is simple, the volume and the weight of the flowmeter are greatly reduced, and the flowmeter can be carried to the field for work.

The utility model discloses a piston includes the gasbag of two intercommunications, and when the sealing washer in the piston certain end outside takes place to reveal, presses the gasbag of this end of fluid oppression for the gasbag of the other end is bloated and with the contact of cylinder body inner wall, leaks in learning the piston through increasing piston motion resistance, has solved among the prior art problem that interior hourglass is difficult to discovery and judgement.

Drawings

In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only one embodiment of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a piston-type flowmeter according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a piston according to an embodiment of the present invention;

FIG. 3 is a front view of an inversion bracket according to an embodiment of the invention;

FIG. 4 is a side view of an inverted bracket according to an embodiment of the present invention;

wherein, 1-cylinder body, 101-guide groove, 102-cylinder body end cover, 2-piston, 201-first sealing ring, 202-second sealing ring, 203-third sealing ring, 204-first air bag, 205-second air bag, 206-groove, 207-air bag connecting pipe, 3-guide rod, 4-displacement sensor, 401-magnetic ring, 6-first pipeline, 601-fluid outlet, 602-first valve, 603-second valve, 604-first exhaust valve, 7-second pipeline, 701-fluid inlet, 702-third valve, 703-fourth valve, 704-second exhaust valve, 8-turning bracket, 801-supporting base, 802-outer frame, 803-positioning pin, 804-rotating shaft, 805-fixed clamping groove, 806-connecting pull rod, 807-limit pin and 808-caster.

Detailed Description

The technical solution of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

As shown in fig. 1, the utility model provides a piston flowmeter, including cylinder body 1, piston 2, guide bar 3, displacement sensor 4, temperature sensor, two sets of pipelines and control module. The top of the cylinder body 1 is provided with a guide groove 101 communicated with the cylinder body 1, the piston 2 is arranged in the cylinder body 1, the piston 2 is vertically provided with a guide rod 3, the guide rod 3 and the guide groove 101 are coaxially arranged, the guide rod 3 is positioned in the cylinder body 1 and the guide groove 101, and the guide rod 3 is of an inner hollow structure. The guide rod 3 of the flowmeter is positioned in the cylinder body 1, the problem of dynamic sealing does not exist, the occurrence of leakage accidents is reduced, and the maintenance workload is reduced. Cylinder end covers 102 are also provided at the top and bottom of the cylinder 1, respectively.

The two groups of pipelines comprise a first pipeline 6 and a second pipeline 7; one end of the first pipeline 6 is communicated with the top of the guide groove 101, the other end of the first pipeline 6 is communicated with the bottom of the cylinder 1, the first pipeline 6 is provided with a fluid outlet 601, and the pipelines at two sides of the fluid outlet 601 are respectively provided with a first valve 602 and a second valve 603. One end of the second pipeline 7 is communicated with the top of the cylinder body 1, the other end of the second pipeline 7 is communicated with the bottom of the cylinder body 1, a fluid inlet 701 is arranged on the second pipeline 7, and a third valve 702 and a fourth valve 703 are respectively arranged on pipelines on two sides of the fluid inlet 701. The first and second pipelines 6 and 7 are further provided with a first and

second exhaust valve

604 and 704 for exhausting the gas in the first and second pipelines 6 and 7.

The displacement sensor 4 is used for detecting the position information of the piston 2, one end of the displacement sensor 4 is arranged at the top of the guide groove 101, and the other end of the displacement sensor 4 extends to the inner hollow structure of the guide rod 3, so that the piston 2 is ensured to have corresponding position detection data at any position without departing from the control of the control module; the temperature sensor is used to detect the temperature of the fluid in the pipe or cylinder 1, and the temperature sensor 5 is provided at the fluid outlet 601. The displacement sensor 4, the temperature sensor, the first valve 602, the second valve 603, the third valve 702, the fourth valve 703 and the exhaust valve are all connected with the control module.

The utility model discloses a control module adopts the PLC controller, and the PLC controller corresponds this type of control program of switching of valve according to the piston position information control that displacement sensor detected is prior art, can refer to application number for CN201120356861.5, and the name is a hydraulic control system's of hydraulic pressure automatic control stroke drilling machine patent document still can refer to application number for CN200610025193.1, the name is the patent document of large-traffic proportional control water valve. The circuit diagram of the connection between the PLC controller and the displacement sensor is also the prior art, and refer to the patent document with the application number of CN201420670750.5 and the name of synchronous detection circuit for double-suspension-point retraction device.

The specific control process of the valve and flow detection is as follows:

1. when the initial position of the piston 2 is the bottom of the cylinder 1, the control module controls the fourth valve 703 and the first valve 602 to be opened according to the initial position information of the piston 2, the third valve 702 and the second valve 603 to be closed, and the piston 2 moves upwards under the fluid movement pressure to drive the guide rod 3 to move upwards along the displacement sensor 4; and the control module calculates the flow of the fluid according to the position information of the piston detected by the displacement sensor. The flowmeter can be used for calibrating and calibrating a static volume method water flow standard device, a water meter calibrating device and various liquid flowmeters.

2. When the initial position of the piston 2 is the top of the cylinder 1, the control module controls the third valve 702 and the second valve 603 to be opened according to the initial position information of the piston 2, the fourth valve 703 and the first valve 602 to be closed, and the piston 2 moves downwards under the fluid movement pressure to drive the guide rod 3 to move downwards along the displacement sensor 4; the control module calculates the flow of the fluid according to the position information of the piston detected by the displacement sensor 4.

The specific calculation formula of the flow and the temperature correction formula are both in the prior art.

The specific calculation formula of the instantaneous flow is as follows: q = N × f/t (1)

Where q represents the instantaneous flow rate, N represents the displacement of the piston movement, f represents the indexing capacity on the piston, and t represents the time of the piston movement. The index volume refers to the volume corresponding to each length unit.

The specific calculation formula of the accumulated flow is as follows: q = N × f (2)

The temperature sensor is used for detecting the temperature of fluid, corrects the flow according to the fluid temperature to obtain standard flow, improves the flow measurement precision, and the specific correction formula is as follows: q₂₀=Q(1+β(20-T））（3）

Wherein Q is₂₀which represents the cumulative flow at 20 deg., i.e., the standard cumulative flow, β indicating the coefficient of bulk expansion of the fluid, and T represents the temperature of the fluid.

The utility model discloses still include the timing module that links to each other with control module, through timing module record measuring time, obtain the average flow in this measuring time by control module according to the flow in measuring time and the measuring time again.

The utility model discloses a control of valve can make piston uninterruptedly reciprocating motion in order to realize the continuous measurement of flow, and the removal of piston 2 relies on fluid pressure and realizes, is a passive removal, need not driving motor and lead screw subassembly etc. the volume and the weight of the flowmeter that have significantly reduced. The displacement sensor 4 adopts a magnetostrictive displacement sensor, and the magnetic ring 401 is not in direct contact with the detection rod 402 and is not rubbed or abraded, so that the magnetic displacement sensor has the advantages of long service life, strong environmental adaptability, high reliability, good safety and relatively high detection precision.

As shown in fig. 2, the piston 2 includes a piston body, and a first seal ring 201, a first air bag 204, a second seal ring 202, a second air bag 205, and a third seal ring 203 which are sequentially provided on the outer periphery of the piston body; the first air bag 204 and the second air bag 205 are communicated through an air bag connecting pipe 207, and the outer diameters of the first air bag 204 and the second air bag 205 are smaller than the inner diameter of the cylinder 1.

In this embodiment, the number of the first seal ring 201 and the number of the third seal ring 203 are both one, and the number of the second seal rings 202 is two, and the piston 2 and the cylinder 1 are sealed by four seal rings. A groove 206 is formed in the piston body between the two second seal rings 202, and the groove 206 is used for placing lubricating oil to lubricate the cylinder body 1 and the piston 2.

Under normal conditions, the air pressure between the first air bag 204 and the second air bag 205 is balanced, and the outer diameter of the air bags (namely the first air bag 204 and the second air bag 205) is smaller than the inner diameter of the cylinder 1, so that the air bags do not influence the normal movement of the piston 2; when the sealing ring at the outer side of one end of the piston 2 leaks, the pressurized fluid can reach the side air bag and press the side air bag, so that the air bag at the other side is expanded to be in contact with the inner wall of the cylinder body 1, the running resistance of the piston 2 is greatly increased, and the internal leakage can be judged through the instantaneous flow curve or the pressure change of the water inlet end.

For example, when the first sealing ring 201 leaks, the first air bag 204 is pressed by the fluid, so that the second air bag 205 is inflated to contact with the inner wall of the cylinder 1; when the third sealing ring 203 leaks, the second air bag 205 is pressed by the fluid, so that the first air bag 204 is expanded to be contacted with the inner wall of the cylinder body 1; both of these conditions will result in an increase in the running resistance of the piston 2 and thus in a decrease in the instantaneous flow, so that the corresponding internal leakage can be judged from the instantaneous flow curve.

As shown in fig. 3 and 4, the piston flowmeter further includes a roll-over stand 8, the roll-over stand 8 including a support base 801, an outer frame 802, a dowel pin 803, and a caster 808; the cylinder body 1 of the piston-type flowmeter is fixed in the outer frame 802 through the fixing clamping grooves 805, and as the cylinder body 1 is a cylinder in the embodiment, the two ends of the cylinder body 1 can be clamped through the fixing clamping grooves 805 at the two ends, so that the cylinder body 1 can be fixed in the outer frame 802 conveniently; the outer frame 802 is also provided with a connecting pull rod 806, and the connecting pull rod 806 connects the frames on the two sides of the cylinder body 1, so that the whole outer frame 802 is firmer; a rotating shaft 804 is arranged on the outer frame 802, a clamping groove is arranged on the supporting base 801, the rotating shaft 804 is arranged in the clamping groove, and the position of the rotating shaft 804 is limited by a limiting pin 807, so that the rotating shaft 804 rotates in the clamping groove, and the piston type flowmeter with the outer frame 802 rotates on the supporting base 801 to facilitate the overturning of the flowmeter; meanwhile, a positioning pin 803 is arranged between the outer frame 802 and the supporting base 801, so that the piston-type flowmeter is fixed on the supporting base 801 when not turned over, and is prevented from swinging on the supporting base 801 during working. The side of the outer frame 802 is also provided with a caster 808, the limit pin 807 and the positioning pin 803 are removed, and the rotating shaft 804 is taken out from the clamping groove, so that the flowmeter with the outer frame 802 is taken out from the supporting base 801, the movement of the flowmeter can be realized through the caster 808, and the carrying and carrying are convenient.

The above disclosure is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or modifications within the technical scope of the present invention, and all should be covered by the scope of the present invention.

Claims

1. A piston flow meter, comprising:

the top of the cylinder body (1) is provided with a guide groove (101), and the guide groove (101) is communicated with the cylinder body (1);

a piston (2) arranged in the cylinder body (1);

the guide rod (3) is arranged on the piston (2), and the guide rod (3) is arranged in the cylinder body (1) and/or the guide groove (101) and is of an inner hollow structure;

one end of the displacement sensor (4) is arranged at the top of the guide groove (101), and the other end of the displacement sensor (4) extends to the inner hollow structure of the guide rod (3); one end of each group of pipelines is communicated with the top of the cylinder body (1), and the other end of each group of pipelines is communicated with the bottom of the cylinder body (1);

a fluid inlet and outlet arranged on each group of pipelines; the fluid inlet and outlet is a fluid inlet (701) or a fluid outlet (601);

and the control module is connected with the displacement sensor (4) and the valve.

2. A piston flowmeter as claimed in claim 1, wherein: the displacement sensor (4) is a magnetostrictive displacement sensor, a magnetic ring (401) of the displacement sensor is arranged at the top of the guide rod (3), and a detection rod (402) of the displacement sensor penetrates through the magnetic ring (401) and extends to an inner hollow structure of the guide rod (3).

3. A piston flowmeter as claimed in claim 1, wherein: the pipelines comprise two groups, wherein the fluid inlet and outlet on one group of pipelines are fluid inlets (701), and the fluid inlet and outlet on the other group of pipelines are fluid outlets (601); the pipelines on the two sides of the fluid outlet (601) are respectively provided with a first valve (602) and a second valve (603), and the pipelines on the two sides of the fluid inlet (701) are respectively provided with a third valve (702) and a fourth valve (703).

4. A piston flowmeter as claimed in claim 1, wherein: the valve is an angle seat valve.

5. A piston flowmeter as claimed in claim 1, wherein: the temperature sensor is connected with the control module.

6. A piston flowmeter as claimed in claim 1, wherein: the device also comprises a timing module connected with the control module.

7. A piston flowmeter as claimed in claim 1, wherein: the piston (2) comprises a piston body, and a first sealing ring (201), a first air bag (204), a second sealing ring (202), a second air bag (205) and a third sealing ring (203) which are sequentially arranged on the periphery of the piston body; the first air bag (204) is communicated with the second air bag (205), and the outer diameters of the first air bag (204) and the second air bag (205) are smaller than the inner diameter of the cylinder body (1).

8. A piston flowmeter as claimed in claim 7, wherein: the number of the first sealing ring (201), the second sealing ring (202) and the third sealing ring (203) is at least one.

9. A piston flowmeter as claimed in claim 7, wherein: and a groove (206) is formed in the piston body between the first sealing ring (201) and the third sealing ring (203).

10. A piston flowmeter as claimed in claim 1, wherein: the turnover device is characterized by further comprising a turnover bracket (8), wherein the turnover bracket (8) comprises a supporting base (801) and an outer frame (802); the piston type flowmeter is fixedly arranged in an outer frame (802), and the outer frame (802) is rotatably arranged on the support base (801).

11. A piston flowmeter as claimed in claim 10, wherein: positioning pins (803) are arranged between the supporting base (801) and the outer frame (802), and casters (808) are arranged on the outer frame (802).