Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
  • G01F1/05—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects
  • G01F1/20—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow
  • G01F1/32—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow using swirl flowmeters
  • G01F1/3227—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using mechanical effects by detection of dynamic effects of the flow using swirl flowmeters using fluidic oscillators
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
  • G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
  • G01F1/66—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by measuring frequency, phase shift or propagation time of electromagnetic or other waves, e.g. using ultrasonic flowmeters
  • G01F1/662—Constructional details
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F15/00—Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
  • G01F15/005—Valves
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F3/00—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
  • G01F3/00—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow
  • G01F3/02—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement
  • G01F3/20—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement having flexible movable walls, e.g. diaphragms, bellows
  • G01F3/22—Measuring the volume flow of fluids or fluent solid material wherein the fluid passes through the meter in successive and more or less isolated quantities, the meter being driven by the flow with measuring chambers which expand or contract during measurement having flexible movable walls, e.g. diaphragms, bellows for gases

Definitions

• the invention relates to a gas meter comprising an enclosure provided with a supply and an outlet for a gas flow, a measuring block which is arranged inside said enclosure and provided with at least an opening allowing the introduction of the flow of gas into said block.
• the opening which allows the introduction of the flow of gas into the measuring block is arranged in a wall of said block which is located opposite the supply of gas.
• the present invention aims to remedy this problem by proposing a gas meter of very simple design which makes it possible to avoid such an increase in pressure drops over time.
• the present invention thus relates to a gas meter comprising an enclosure provided with a supply and an outlet for a gas flow, a measuring block which is disposed inside said enclosure and provided with at least one opening allowing the gas flow to be introduced into said block, characterized in that the measuring block (18) has a wall (18a) disposed opposite the inlet (14) of the gas flow and that meets said flow coming from the supply, said opening being only arranged in the opposite wall (18b) of said measuring block.
• the flow To reach the opening (or openings) arranged in the opposite wall of the measuring block, the flow must bypass said block which acts as a screen and, thanks to this movement, said flow gets rid of most of it. particles.
• the measuring block comprises transducers emitting and receiving ultrasonic waves in the flow of gas which propagates in said measuring block, it may be advantageous to eliminate parasitic ultrasonic waves which are generated externally at the counter at the frequency (s) used by the transducers and which may disturb the measurements.
• the counter may include means for attenuating these parasitic ultrasonic waves which are arranged between the supply of the gas flow and the opening (or openings).
• the enclosure and the measurement block provide between them at least one passage allowing the flow of gas from the supply to reach the opening.
• the means for attenuating parasitic ultrasonic waves are arranged in the passage.
• the passage is substantially vertical.
• the attenuation means are for example formed by a plurality of consecutive grooves transverse to the main direction of propagation of the parasitic ultrasonic waves in said passage, mutually parallel and alternated with projections so as to create a break in acoustic impedance in this passage.
• the grooves and protrusions can for example be made on the measuring block.
• the attenuation means can also be made of a material attenuating parasitic ultrasonic waves and forming a coating on at least part of the surface of the measuring block.
• the measuring block can also comprise a fluidic oscillator replacing the ultrasonic transducers or else a fluidic oscillator combined with these ultrasonic transducers as described in patent application FR 2 721 360.
• the arrangement of the opening (or openings ) on the opposite wall of the measuring block allows to install, opposite this opening, a member allowing the closing of the latter and which is not visible from the gas supply due to the presence of the measuring block .
• This arrangement limits the possibilities of fraud which may arise, for example, in the case where the user has not paid his gas consumption bill and that consequently the gas distributor has ordered the shutter of the opening of the measuring block and therefore elimination of gas distribution.
• the shutter member is for example mounted on the measuring block.
• the measuring block is made of a plastic material in order to facilitate the mounting of the shutter member on said block.
• FIG. 1 is a schematic view in longitudinal section of a gas meter according to the invention
• FIG. 2 is a sectional view along A-A of the counter shown in FIG. 1,
• FIG. 3 is a sectional view along BB of the counter shown in Figure 1
• - Figure 4 is a view of the meter measurement block shown in Figure 1 and which includes means for attenuating parasitic ultrasonic waves generated externally to said counter,
• FIG. 5 is a view of another type of measuring block used in the counter shown in Figure 1
• - Figure 6 is a sectional view along C-C of the measuring block shown in Figure
• FIG. 7 is an enlarged view of the counter shown in Figure 1 and which includes means for attenuating parasitic ultrasonic waves generated externally to said counter according to a variant of those shown in Figure 4,
• - Figure 8 is a view enlarged in cross section along DD of the counter shown in FIG. 7 in which the interior of the measuring block has not been shown,
• FIG. 9 is a view of a gas meter similar to that of Figure 7 but not comprising means for attenuating parasitic ultrasonic waves and in which is shown a member for closing the opening of the block of measurement.
• a gas meter designated by the general reference denoted 10 comprises an enclosure 12 to which are connected a gas supply 14 and a gas outlet 16 and a measuring block 18 disposed inside enclosure 12.
• the measuring block 18 has a wall 18a which is located opposite the gas supply 14 and on which the gas flow is fractionated. Under this effect dynamic the gas flow gets rid of part of the particles it carries.
• the measuring block 18 is arranged inside the enclosure 12 so as to provide between these one or more passages in which the fluid is distributed (figs 1 and 3) to reach the supply 14 to a opening 20, made in the lower part of the measuring block.
• a dust trap can be set up at the bottom of the enclosure.
• the measuring block 18 is held in position inside the enclosure 12 by two stops 22, 24 which are housed in recesses arranged in the interior walls of said enclosure 12.
• the measurement block 18 of substantially parallelepiped shape comprises, arranged in a wall 18b opposite the wall 18a, the opening 20 through which the gas flow enters said block as well as two ultrasonic transducers 26 , 28 each arranged opposite one of the opposite ends of a measurement conduit 30 of tubular shape and which constitutes the ultrasonic measurement path
• the ultrasonic transducers operate for example at a frequency of 40 kHz.
• the measurement conduit 30 is arranged in a wall 32 forming a solid block which separates two chambers inside which the transducers 26, 28 are arranged.
• the gas enters one of the chambers of the measuring block 18 through the opening 20, as indicated by the arrows in FIGS. 1 and 3, rushes into the measuring tube
• the ultrasonic transducers 26, 28 emit and receive alternately ultrasonic waves at a fixed ultrasonic frequency and, from the ultrasonic waves received by each from said transducers, the propagation time of these waves is measured and the fluid flow rate is deduced from these measurements.
• the particles are not likely to be deposited on the active faces of the transducers, to modify the emission and the reception of the ultrasonic waves and therefore to considerably disturb the flow measurements.
• the space left at the bottom of the enclosure is generally occupied for installing the appropriate electronics and the energy source (not shown) necessary for determining the gas flow rate.
• a pressure regulator not shown in these figures, is placed upstream of the gas meter and generates in the pipeline and in the gas meter parasitic ultrasonic waves at a frequency for example equal to 40 kHz which disturb the measurement of the flow gas.
• the measuring block acts as a screen between the supply and the opening of the said block and plays in a way the role of an anti-noise wall
• the parasitic waves which emerge in the enclosure with the flow of gases are naturally attenuated by the multiple reflections which are generated in contact with the wall 18a and the interior walls of said enclosure.
• the opening in the measuring block is arranged in the wall 18a located opposite the gas supply (prior art)
• the noise propagated by the flow penetrates more easily into the measuring block than 'with the new arrangement of the opening facing the bottom of the enclosure.
• FIGS 5 and 6 show a measuring block 40 of a gas meter similar to that of Figures 1 to 3 and whose elements which have not been modified from Figures 1 to 3 retain the same references.
• This measurement block consists of a fluidic oscillator in which the gas flow penetrates through the opening 20 and enters a channel 42 which ends in a slot 44 of elongated shape and which opens onto a chamber 46.
• An obstacle 48 is housed in the middle of the chamber opposite the slot 44.
• the slot transforms the flow into a jet of fluid oscillating naturally in the chamber 46 and sweeping the front wall 48a of the obstacle 48 with a so-called oscillation frequency representative of the flow rate having passed through the fluidic oscillator.
• the jet gives uh has flows which escape alternately, according to the oscillations of said jet, by lateral channels 50, 52 framing the obstacle 48 and join downstream of said obstacle to borrow the vertical channel 54 connected to the orifice of outlet 34
• Figures 7 and 8 show a gas meter 56 similar to that of Figures 1 to
• each of the aforementioned passages 60, 62, 64, 66 is delimited by two facing surfaces respectively 68, 70, 72, 74, 76, 78, 80, 82 and one of them which is that 70 , 74, 78, 82 of the measuring block 58 is provided with a plurality of consecutive projections 84 obtained for example by overmolding and alternated with depressions 86
• FIG. 9 illustrates another advantageous characteristic linked to the arrangement of the opening of the measuring block according to the invention.
• the gas meter 88 shown comprises a measurement block 90 whose opening
• a cut-off member 94 is mounted under the measuring block, opposite the opening 92 in order to be able to close the latter if necessary.
• Such a member 94 comprises a valve 96 in contact with the valve seat which coincides with the opening in FIG. 9, a rack mechanism 98, partially shown, which is actuated by a motor 100 and thus allows the movement of said valve. rotating around an axis 102.
• the cut-off device By placing the cut-off device below the measuring block, the risks associated with fraud are reduced compared to the counters of the prior art in which said device is necessarily positioned near the gas supply.
• the opening 92 could be placed in another location insofar as the shutter member remains hidden from the supply 14 by the measuring block 90
• the lower part of the counter is more spacious for housing the motor 100 of the cutter member than in the upper part where the supply 14, the orifice 34 and the discharge 16 limit possible locations
• the measuring block in a plastic material, it is easy to overmold on the outer wall of said block parts which will allow the reliable fixing of the breaking member 94 on said block (for example the parts around which the axis 102 is articulated).
• the cut-off member is fixed to the interior of the meter on the gas supply 14 or close to it.
• the enclosure 12 of the counter is made of metal, for reasons of temperature resistance, it is therefore difficult to fix the cut-off member in a simple and reliable manner.

Landscapes

• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• General Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Measuring Volume Flow (AREA)
• Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9497162

Family Applications (1)

Country Status (11)

Families Citing this family (9)

Family Cites Families (7)

• 1996
  • 1996-10-28 FR FR9613219A patent/FR2755232B1/fr not_active Expired - Fee Related
• 1997
  • 1997-10-27 WO PCT/FR1997/001919 patent/WO1998019137A1/fr not_active Application Discontinuation
  • 1997-10-27 CN CN97199139A patent/CN1234864A/zh active Pending
  • 1997-10-27 BR BR9712629-2A patent/BR9712629A/pt not_active Application Discontinuation
  • 1997-10-27 EP EP97912260A patent/EP0934508A1/fr not_active Ceased
  • 1997-10-27 KR KR1019990703700A patent/KR20000052862A/ko not_active Application Discontinuation
  • 1997-10-27 CA CA002268790A patent/CA2268790A1/fr not_active Abandoned
  • 1997-10-27 HU HU9904297A patent/HUP9904297A2/hu unknown
  • 1997-10-27 AU AU49518/97A patent/AU723240B2/en not_active Ceased
  • 1997-10-27 PL PL97332943A patent/PL332943A1/xx unknown
  • 1997-10-28 AR ARP970104991A patent/AR010046A1/es unknown

Non-Patent Citations (1)

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