JPH05142017A - Testing apparatus for flowmeter - Google Patents

Abstract

PURPOSE:To automate discrimination of acceptance and reject and to make the discrimination efficient by a method wherein a meter to be tested is set fixedly at a prescribed position with an outer peripheral wall hood of a testing chamber opened and closed, a vortex generator is fitted by insertion to a main channel, and tests are executed sequentially for a plurality of reference flow rates with a flow regulating plug moved. CONSTITUTION:A testing chamber 3 is closed hermetically by a cylindrical hood 4 opened and closed by an air pressure opening-closing cylinder 5. The hood 4 being opened first, a flowmeter to be tested is inspected visually for a defect such as deformation beforehand and then fitted at a prescribed position on a workpiece stage communicating with a conduit 7, and the hood 4 is closed. Subsequently, a vortex generator for a flow rate test is fitted by insertion to a main channel of the flowmeter. Simultaneously with this fitting, a flow regulating plug insertion means which sets the amount of insertion of a flow regulating plug for regulating the cross-sectional area of a subordinate channel is made to operate. The central flow rate of a plurality of test flow rates being made a control point, a reference flow rate generating device 8 is set at this point, the flow regulating plug is adjusted and a test is executed. Tests are executed sequentially for the other test flow rates in the same way, and determination of acceptance or reject is conducted.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD A vortex flowmeter is a flowmeter that utilizes the fact that the number of Karman vortices generated per unit time in a predetermined Reynolds region is substantially constant, and its flow characteristics depend on the physical properties of liquids and gases. However, since it is determined depending on the Reynolds number, it has recently come to be used for an air flow meter for an internal combustion engine such as an automobile engine. In modern internal combustion engines,
The air flow rate is determined by the accelerator amount, and the amount of fuel corresponding to the air flow rate is injected, and the fuel is injected into the piston as a gas-liquid mixed gas and burned. The predetermined internal combustion engine is provided with a vortex flowmeter in a predetermined air flow rate range. However, in general, the main body that forms the flow path is resin-molded, so that it is deformed, and even in the same type of flowmeter, some instrumental error variation occurs. In a low power internal combustion engine,
Since the air flow rate is relatively small, a normal vortex flowmeter with a vortex generator inside the flow path is used as the flowmeter.
Usually, it is performed by changing the flow passage cross-sectional area. On the other hand, in a high output vortex flowmeter for an internal combustion engine, in order to reduce pressure loss, the main body of the vortex flowmeter is divided into a main flow path and a sub flow path in the flow direction, and a vortex generator is installed only in the main flow path. Then, the sub-flow passage cross-sectional area is adjusted so that the air flow rate ratio flowing through the main flow passage and the sub-flow passage becomes constant.

[0002]

2. Description of the Related Art A flow meter under test is tested by injecting a plurality of test flow rates of air. As described above, a small vortex flowmeter has a main flow path and a large vortex flowmeter has a sub flow path. Although the cross-sectional area is adjusted to the specified flow rate, in the conventional flow meter test device, the work of adjusting the flow path cross section is involved each time one flow rate test is performed, so an inefficient and inexpensive air flow meter should be used. Could not be offered.

[0003]

[Purpose] The present invention has been made in view of the above-mentioned circumstances, and a flow meter under test is efficiently arranged in a flow meter test device,
The purpose of the present invention is to provide a flow meter test device that automatically tests and adjusts the flow rate so as to obtain a flow rate of a standard value, and judges pass / fail.

[0004]

In order to achieve the above object, the present invention provides (1)
An outside air introduction path, a flow meter test chamber, a reference flow rate generator,
In a flow meter test device, in which a vacuum pump is sequentially connected in series and a flow meter under test inserted in the flow meter test chamber is compared with a reference flow rate generated by the reference flow generation device, the flow meter under test has an outer circumference. A vortex flowmeter comprising: a tubular main body having a collar portion on its inner side; a vortex generator inserted in a direction perpendicular to the axis of the main body; and a flow rate adjusting plug for varying the cross-sectional area of the tubular body. ) A hood opening / closing means for opening / closing the hood which is the outer peripheral wall of the flow meter test chamber, and b) a flow path meter, which is provided on the flow path of the test room and is a flange of the flow path meter to be tested at a fixed position forming part of the flow path. Main body locking means for locking the parts, c) vortex generator insertion means for inserting the vortex generator in the main flow path, and d) predetermined in the flow path for determining the flow path area of the flow path. Flow adjusting plug position adjusting means for rotationally driving the flow adjusting plug to the depth, and e) predetermined in the measured flow meter. In the test flow rate, the flow rate adjustment plug insertion means is instructed to move the flow rate adjustment plug so that the flow rate becomes the reference flow rate, and after the adjustment is completed, a plurality of reference flow rates are selected and tested, and the pass / fail judgment is made. A control device having a function and a function of mounting a flowmeter under test for driving the hood opening / closing means, the main body locking means, and the flow rate adjusting plug inserting means.
Furthermore, (2) In (1) above, the flowmeter under test has a flange portion on the outer periphery, and is fitted into the main flow passage, and a cylindrical main body that divides the main flow passage and the sub flow passage in the flow direction. A vortex flowmeter that has a vortex generator and a flow rate adjusting plug that is fitted into the sub-flow passage and that changes the flow passage cross-sectional area of the sub-flow passage. Further, (3) the above (1) or (2) ), The adjustment plug has a screw which is detachably movable in the main body wall in a direction perpendicular to the axial direction of the main body, and the movement amount of the adjustment plug is driven by a pulse number corresponding to a predetermined instrumental error adjustment amount. It is characterized by being regulated by the rotation of the pulse motor. Hereinafter, description will be given based on examples of the present invention.

First, a flow meter used in the flow rate test apparatus of the present invention will be described. 6 and 7 are views for explaining an example of the vortex flowmeter to be tested, FIG. 6 is a small vortex flowmeter, FIG. 7 is a large vortex flowmeter, and 60 and 64 are main bodies in the drawings. 61,6
7 is a vortex generator, 62 and 68 are flow rate adjusting plugs, 63 and 6
6 is a rectifying grid, and 65 is a flow dividing plate.

The main bodies 60 and 64 may have the same cross-sectional shape or may be provided with a throttle on the upstream side, but in the figure, in both cases, rectifying grids 63 and 66 are provided on the inflow side to disturb the swirling flow of the inflowing air flow. To remove. In the small vortex flowmeter shown in FIG. 5, the vortex generator 61 is provided symmetrically about the axis, and the flow rate adjusting plug 62 screwed into the main body boss 60b on the wake side is rotated to be exposed in the main body 60. The flow rate characteristics are adjusted according to the amount of exposure. In the large vortex flowmeter, the main body 64 is divided in the flow direction into a main stream 64c and a substream 64d by a flow diverter plate 65, and a vortex generator 67 is arranged only on the mainstream 64c side.
A flow rate adjusting plug 68 is arranged on the 4d side. The total flow rate is the sum of the flow rates of the main stream 64c and the substream 64d,
Once the area ratio is determined, it can be determined by measuring the flow rate of the mainstream 64c. In addition, each vortex flowmeter is the main body 6
The flanges 60a and 64a, which are integrally formed with 0 and 64, support the flow path.

FIG. 1 is a block diagram for explaining an embodiment of a flow meter test apparatus of the present invention. In the figure, 1 is an outside air introduction path, 2 is a filter, 3 is a flow meter test chamber, and 4 is a flow meter test chamber. Hood, 5 is a hood opening / closing cylinder, 6 is a housing, 7 is a conduit, 8
Is a reference flow rate generator, 9 is a nozzle chamber, 10 is a partition wall, 11
Is a sonic nozzle, 12 is a vacuum passage, 13 is a vacuum pump, 14
Is a control device.

In the figure, a flow meter under test (not shown)
Is arranged in the flow meter test chamber 3, and the flow meter test chamber 3 communicates with an outside air introduction path 1 for introducing outside air through a filter 2 for removing dust, and a reference flow rate generator 8 and a conduit 7. Then, it is connected to the vacuum pump 13 via the vacuum passage 12.
The reference flow rate generator 8 is a closed chamber in which the conduit 7 and the vacuum passage 12 are partitioned by a partition wall 10. The partition wall 10 is provided with a plurality of sonic nozzles 11 and 11, and the sonic nozzle 11 is located before and after the partition wall 10. The flow is conducting. The sonic nozzle 11 has a pressure ratio P between the pressure P ₁ on the conduit 7 side and the pressure P ₂ on the vacuum passage 12 side.
_{When 1} / P ₂ becomes the ratio (sonic velocity maintaining range) set for the sonic nozzle 11, it reaches the sonic velocity region (critical flow) of the gas flow, and the constant flow rate is determined by the pressure P ₁ and temperature of the upstream air. This is a reference flow rate generator utilizing the fact that a predetermined reference flow rate is given to the flowmeter under test by selecting from among the plurality of sonic nozzles 11 by opening and closing with an on-off valve or the like.

The flow meter test chamber 3 is a cylindrical chamber that can be opened and closed, and is closed by a cylindrical hood 4 during a test.
The hood 4 is opened and closed by a pneumatically driven hood opening and closing cylinder 5. The flow meter under test has been visually inspected beforehand for any defects such as deformation, and the passed flow meter under test is mounted at a predetermined position on the work table that communicates with the conduit 7, and the hood 4 is closed and tested. Is prepared.

FIG. 2 shows a flowmeter under test (in this description, FIG.
(For vortex flowmeters) of the flowmeter test chamber 3 is installed in the flowmeter test chamber 3, and 20 is a flowmeter mount and 21 is an O-ring holder. , 22 is an O-ring, 23 is an air cylinder, 24 is a fixed lever, 2
5 is a holding metal fitting, 26 is a positioning rod, and 27 is a positioning plate.

The mount 20 has a through hole 2 communicating with the conduit 7.
0a, and a flow meter to be tested 64 (hereinafter referred to as a test flow meter) is supported and arranged so as to form the same flow path in series with the flow hole 20a. It is fixed on the bottom. The flowmeter under test 64 has a mounting hole 46b for the collar 46a.
Is inserted into and supported by the positioning pin 46a of the positioning plate 27 and is disposed in the annular O-ring retainer 21 (at this time, the tip of the retainer fitting 25 is at the position 25a on the dotted line). The positioning pin 46a is formed integrally with the positioning rod 26 and the pressing plate 26a, and the positioning rod 26 is pressed by the spring force of the spring 28 provided between the spring seat provided on the fixed lever 24 and the positioning plate 27. The plate 26a is pressed downward. The O-ring retainer 21 is pressed by this pressing force, and the O-ring 22 hermetically seals the flowmeter under test 64 with the flow hole 20a, and then closes the hood 4 to seal the flowmeter test chamber 3. ..

The fixed lever 24 is an L-shaped member and is used for the mounting base 2.
It is fixed to 0 and support pins 24b and 24c are provided at both ends. The support pin 24b serves as a fulcrum for rotatably supporting the bottom portion by the movement of the air cylinder, and the support pin 24c rotatably supports the holding metal fitting 25. The air cylinder 23 supported by the support pin 24b has a piston 23c fixed to the piston rod 23, and vertically drives the piston 23c by the air pressure introduced into the pressure introducing port 23a or 23b. A U-shaped metal fitting 23e provided with a support pin 23f is fixed to the end of the piston rod 23c. The support pin 23f rotatably supports one end portion of the holding metal fitting 25, and the driving of the air cylinder 23 rotates the holding metal fitting 25 around the support pin 24c to press the collar portion 64a of the flowmeter under test 64 from above. , Flowmeter under test 64
Stablely mount in a precise position.

Next, a vortex generator (referred to as a master vortex generator) for a flow rate test is inserted into the main flow path 64c of the flowmeter under test 64. FIG. 3 is a diagram for explaining the outline of the vortex generator insertion device for mounting the master vortex generator in the flow meter test device of the present invention, in which 30 is a fixed base, 31
Is a guide rod, 32 is a motor, 33 is a pinion, 34
Is a rack, 35 is a moving base, 36 is a vortex generator support frame, 37
Is a master vortex generator, 38 and 39 are position sensors,
Parts having the same functions as those in FIG. 2 are given the same reference numerals.

In the figure, the fixed base 30 is fixed to the mounting base 20, and the fixed base 30 extends in a direction perpendicular to the flow path.
A parallel guide rod 31 (plan view not shown) of the book and a motor 32 are arranged. The guide rod 31 has a bearing 35a and is provided with a movable base 35 which is movable in the axial direction. A rack 34 parallel to the guide rod 31 is fixed to the movable base 35. A pinion 33 is fitted on the shaft of the motor 32 to linearly drive the rack 34. The other end of the moving table 35 has an L shape that moves in parallel with the rack 35 on the guide rod 31, and is provided with a vortex generator support frame 36. The vortex generator support frame 36 is
A frame body in which base plates 36a and 36b perpendicular to the moving direction are configured in parallel by columns 36c. The base plate 36b has a master vortex generator 37 and the master vortex generator 37 at a predetermined position of the flowmeter under test. A guide pin 36d for interposing the guide pin is provided.

The moving table 35 moves between the position sensors 38 and 39. When the movable table 35 stops at the position sensor 38, the tip of the master vortex generator 37 reaches the flow distribution plate 65 of the flowmeter under test 64. A soft rubber 37a is attached to the tip of the master vortex generator 37 to protect the flow distribution plate 65. When the flow meter under test 64 is tested, it is fixed in this state, but when the test is completed, the position sensor 3
The movable table 35 is moved to the position 9 to move the master vortex generator 3
7 is pulled out from the flowmeter under test 64 and the next flowmeter under test 6
Wait for 4 to be installed.

Simultaneously with the insertion of the master vortex generator 64, the flow rate adjusting plug inserting means for determining the insertion amount of the flow rate adjusting plug 68 for adjusting the flow passage sectional area of the sub flow passage 64d operates. 4 (a) and 4 (b) are views for explaining the flow rate adjusting plug insertion device in the flow rate testing device of the present invention, FIG. 4 (a) is a configuration diagram, and FIG. 4 (b) is shown in FIG. a) an enlarged view taken along the line A-A in FIG. 1, in which 40 is a stepping motor (hereinafter referred to as a pulse motor), 41 is a torque clutch, 42 is a pulley, 43 is a belt, 44 is an air cylinder, and 45 is a support frame. , 46 is a moving rotator, 47 is a jig holder, 48 is a spline shaft, 49 is a spring, 50, 5
Reference numeral 1 is a position sensor, and 52 is a movable table, and parts having the same functions as those in FIGS.

In the figure, the flow rate adjusting plug 68 includes
For example, as shown in FIG. 4B, a locking hole 68a corresponding to the convex portion of the insertion jig 48a is provided, the insertion jig 48a and the locking hole 68a are locked, and the insertion jig 48a rotates in accordance with the rotation. The flow rate adjusting plug 68 screwed with the boss 64b moves forward and backward toward the sub flow path. The insertion jig 48a is the jig holder 4
A screw 47 that is detachably attached to the device 7 and is provided in the axial direction.
The a and 47b are guided by the guide groove 47 and are movable only in the axial direction. The insertion jig 48a is joined to the spline shaft 48 in the axial direction, and the spline shaft is inserted so as to be movable in the axial direction within the axis of the moving rotary body 46. A spring 49 is stretched between the jig holder 47 and the moving rotary body 46. However, the jig holder 47 does not come out because the screw 47b is locked in the step groove 47d.

The movable rotary member 46 is rotatably mounted on a movable base 52.
The rotation corresponding to the drive pulse is transmitted via the pulse motor 40, the torque clutch 41, the pulleys 42 and 46a, and the belt 43. The torque clutch 41 is
When a predetermined torque is applied to the moving rotating body 46, slippage,
Rotate. The moving table 52 is driven in the arrow P direction by the air cylinder 44. The air cylinder 44 operates in the same manner as the air cylinder 23, and the piston rod 44d provided on the piston 44a has a moving base 52.
It is supported by a support frame 45 that is fixedly attached to and is driven in the axial direction by introducing air pressure into the air pressure introducing port 44a or 44b of the cylinder 44.

In the operation of the flow rate adjusting plug device having the above-described structure, first, the jig holder 47 causes the flange 47e to drive the air cylinder 44 from the stop position of the position sensor 50 to the position of the position sensor 51 to perform the insertion treatment. The tool 47 is advanced in the direction of the arrow Q to engage the insertion jig 48a with the locking hole 68a of the flow rate adjusting plug 68. At this time, the insertion jig 48a is inserted with an appropriate pressure by the spring force of the spring 49, so that the displacement error due to the looseness between the flow rate adjusting plug and the boss 64e does not occur. Then, the pulse motor 40 rotates the rotation angle according to the number of drive pulses, and rotates the moving rotor 46. The flow rate adjusting plug 68 moves in the axial direction while rotating according to the rotation of the moving rotating body 46.

The operation of the flow meter test apparatus of the present invention described above
The work will be described according to the flowchart. FIG. 5 shows the present invention.
3 is a flowchart in the flow meter test device of FIG.step1 : The flow meter under test 64 has no abnormality by visual inspection.
After confirming the fact, open the hood 4 and place it on the work table 20.
It is installed by inserting the positioning pin 27a into the mounting hole 64b.
Itstep2 : Flowmeter under test 6 according to the sequence described in FIG.
Fix 4 in place. step3 : Insertion of the master vortex generator described in FIG.
Attach the insertion jig 48 to the flow rate adjusting plug 68 described in FIG.
To combine.step4 : Control point, eg test flow rate of flow meter under test
When the point is 5 points, the central flow rate becomes the control point.
Then, the reference flow rate generator 8 is used in advance to set the flow rate at the management point.
Set to.step5 : Flow rate test result of the management point is unacceptable
In this case, the flow rate deviation and the moving amount of the flow rate adjusting plug 68 should be set in advance.
Flow rate adjustment according to flow rate deviation from stored value
In order to give the movement amount of the plug 68, the corresponding drive pulse
The pulse motor 40 is driven by the number of pulses, and the insertion jig 48a
To rotate.step6 : When the flow rate at the control point is within the allowable range
If so, test at the other 4 flow rates sequentially.step7 : If the instrumental error is within ± α% at each flow point
The pulse motor 40 in the direction to further reduce the instrumental error.
Re-test by driving and moving the flow rate adjustment plug 68.
However, if ± α% or less, it is rejected.step8 : Test again at each flow point.step9 : If the instrumental error exceeds ± α%, reject the test.
If yes, make a pass decision.step10 : Pass / Fail judgment is made by the above operation.

[0021]

[Effect] As is apparent from the above description, according to the flowmeter test apparatus of the present invention, the test work is rationalized, so that the test efficiency is remarkably improved, and furthermore, no human error is caused and the cost is low. It is possible to provide various flow meters.

[Brief description of drawings]

FIG. 1 is a configuration diagram for explaining an embodiment of a flow meter test apparatus of the present invention.

FIG. 2 is a diagram for explaining one embodiment of a flow meter device for mounting a flow meter under test in a flow meter test device of the present invention in a flow rate test chamber.

FIG. 3 is a diagram for explaining an outline of a vortex generator insertion device for mounting a master vortex generator in the flow meter test device of the present invention.

FIG. 4 is a view for explaining a flow rate adjusting plug inserting device in the flow rate testing device of the present invention.

FIG. 5 is a flowchart in the flow meter test apparatus of the present invention.

FIG. 6 is a diagram for explaining an example of a vortex flow meter to be tested.

FIG. 7 is a diagram for explaining an example of a vortex flow meter to be tested.

[Explanation of symbols]

1 ... Outside air introduction path, 2 ... Filter, 3 ... Flow meter test chamber, 4
... Hood, 5 ... Hood opening / closing cylinder, 6 ... Casing, 7 ... Conduit, 8 ... Reference flow rate generator, 9 ... Nozzle chamber, 10 ... Partition wall, 11 ... Sonic nozzle, 12 ... Vacuum path, 13 ... Vacuum pump, 14 …Control device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitsugu Nakagawa 3-10-8 Kamiochiai, Shinjuku-ku, Tokyo Oval Equipment Industry Co., Ltd.

Claims (3)

[Claims] 1. An outside air introduction path, a flowmeter test chamber, a reference flow rate generator, and a vacuum pump are sequentially connected in series, and a flowmeter under test inserted in the flowmeter test chamber generates the reference flow. In a flow meter test device for comparing with a reference flow rate generated by the device, the flow meter under test is a tubular main body having a collar portion on the outer periphery, and a vortex generator inserted in a direction perpendicular to the axis of the main body, A vortex flowmeter having a flow rate adjusting plug for varying the cross-sectional area of the tubular body, comprising: a) a hood opening / closing means for opening / closing a hood that is an outer peripheral wall of the flowmeter test chamber; and b) a flowmeter test chamber flow. Main body locking means provided on the road for locking the flange of the flowmeter under test at a fixed position forming a part of the flow path, and c) Inserting the vortex generator for inserting the vortex generator in the main flow path. And d) rotating the flow rate adjusting plug to a predetermined depth in the channel to determine the channel area of the channel. Flow adjusting plug position adjusting means for adjusting the flow rate, and e) instructing the flow adjusting plug inserting means for the amount of movement of the flow adjusting plug so as to become the reference flow rate at the predetermined test flow rate of the measured flow meter, and the adjustment is completed. After that, a plurality of reference flow rates are selected and tested, and a pass / fail determination function for determining pass / fail, and a flowmeter under test mounting function for driving the hood opening / closing means, the main body locking means, and the flow rate adjustment plug insertion means are provided. A flow meter test device comprising: a control device. 2. The flowmeter under test has a flange on the outer circumference, and has a cylindrical main body that divides the main flow passage and the sub-flow passage in the flow direction, a vortex generator that is fitted into the main flow passage, and a sub-stream. A flowmeter test device, which is a vortex flowmeter having a flow rate adjusting plug that is inserted into a channel and that varies a channel cross-sectional area of the sub-channel. 3. The adjustment plug has a screw on a main body wall that is detachably movable in a direction perpendicular to the axial direction of the main body, and the amount of movement of the adjustment plug corresponds to a predetermined instrumental error adjustment amount. 3. The flow meter test device according to claim 1, wherein the flow meter test device is defined by rotation of a pulse motor driven by.