CN101788323B - Commutator of water flow standard device and commutation method thereof - Google Patents

Commutator of water flow standard device and commutation method thereof Download PDF

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Publication number
CN101788323B
CN101788323B CN2010101095937A CN201010109593A CN101788323B CN 101788323 B CN101788323 B CN 101788323B CN 2010101095937 A CN2010101095937 A CN 2010101095937A CN 201010109593 A CN201010109593 A CN 201010109593A CN 101788323 B CN101788323 B CN 101788323B
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shunt
commutator
commutation
chamber
flow
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CN101788323A (en
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马龙博
郑建英
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Zhejiang Province Institute of Metrology
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Zhejiang Province Institute of Metrology
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Abstract

The invention discloses a commutator of a water flow standard device and a commutation method of the commutator. The commutator comprises a commutation nozzle, a first flow divider, a first commutation flow channel, a second commutation flow channel, a commutator timing guide rod and an optical-electrical converter. The commutator timing guide rod and the optical-electrical converter are matched with each other, the commutator timing guide rod is fixedly connected with the first flow divider, a second flow divider is arranged below the first commutation flow channel and the second commutation flow channel, the inside of the second flow divider is provided with a first flow dividing chamber, a measuring chamber and a second flow dividing chamber isolated with each other, the first flow dividing chamber and the second flow dividing chamber are respectively arranged on two sides of the measuring chamber, the measuring chamber, the first flow dividing chamber and the second flow dividing chamber are respectively provided with a water inlet and a water outlet, the water inlets of the first flow dividing chamber and the water inlet of the second flow dividing chamber respectively correspond to the water outlet(s) of the first commutation flow channel and /or the water outlet of the second commutation flow channel, and the bottom of the measuring chamber is provided with the water outlet. With the realization of 'swap in / swap out in the same direction' of the commutator, the invention improves the measuring accuracy of the water flow standard device.

Description

Commutator in a kind of water flow standard apparatus and commutation method thereof
Technical field
The present invention relates to commutator and commutation method thereof in a kind of water flow standard apparatus.
Background technology
In the present domestic and international measurement technology mechanism, the commutator that water flow standard apparatus uses mainly contains two kinds: the one, and the enclosed commutator; The 2nd, " pants " formula open type commutator.These two kinds of commutators have satisfied the transmission of quantity value requirement in current detection, the calibrating to a certain extent, but development along with the liquid flow mearuement technology, above-mentioned commutator can not well satisfy the more and more higher requirement of instrument measurement precision, and therefore the problem that in use exposes is also more and more.Water flow disturbance problem as the enclosed commutator, when commutator commutates suddenly, flow rate of water flow and pressure all will take place sharply to change, produce surge wave, this surge wave will be propagated to entrance along pipeline, thereby cause the disturbance of the water of steady flow condition, and then influence the metering performance of flowmeter.Because above-mentioned water flow disturbance problem is the major defect that the enclosed commutator can't overcome, so the use amount of this type commutator in water flow standard apparatus is fewer and feweri, " pants " formula open type commutator that gradually current is not produced disturbance replaces; Fig. 1 has provided " pants " formula open type commutator structure and has formed.Among Fig. 1, " pants " formula open type commutator comprises the commutator timing guide rod 4 and the photoelectric commutator 5 of commutation nozzle 1, first shunt 2, the first commutation runner 31, the second commutation runner 32, mutual coupling.Wherein, first shunt 2 has the lower end of the first adjacent shunting funnel 21 and the second shunting funnel, 22, the first shunting funnels 21 and the second shunting funnel 22 respectively to first guide wire 211 and second guide wire 222 should be arranged; In addition, the lower end of first guide wire 211 and second guide wire 222 places the first commutation runner 31 and the second commutation runner 32 respectively accordingly; Commutator timing guide rod 4 is fixedly connected with first shunt 2 and match with photoelectric commutator 5 and to produce the timing control signal.Because the shape of first guide wire 211 and second guide wire 222 and the first commutation runner 31 and the second commutation runner 32 exactly likes " pants ", the open type commutator that therefore has this kind structure is called as " pants " formula open type commutator.Its principle of work and corresponding commutation discharge model can be represented by Fig. 2.The course of work of this type commutator can be divided into following several stages as seen from Figure 2: 1. t 0-t 10Stage begins to be changed to test tank by by-pass pipe at this stage commutator, and the current of nozzle ejection flow into test tank gradually by by-pass pipe, the not timing of timer this moment, and this process flows into the semi-invariant of the water of test tank and represents with A; 2. t 10-t 20Stage changes to gradually fully at this stage commutator, and timer begins by t 10Timing constantly, nozzle ejection current flow into test tank gradually fully, and this process flows into the current semi-invariant of test tank and represents with B; 3. t 20-t 30In the stage, commutator commutation finishes in stage in this, and the current of nozzle ejection enter test tank fully, the timer t that continues 10-t 20Stage is proceeded continuous timing, and this process flows into the current semi-invariant of test tank and represents with G; 4. t 30-t 40Stage begins to be swapped out to by-pass pipe by test tank at this stage commutator, and the current of nozzle ejection flow into by-pass pipe gradually by test tank, the timer t that continues 20-t 30Stage is proceeded continuous timing, and this process flows into the current semi-invariant of test tank and represents with E; 5. t 40-t 50Stage is swapped out to by-pass pipe by test tank gradually fully at this stage commutator, and timer is at moment t 40Stop timing, and the current of nozzle ejection also flow into by-pass pipe gradually fully, this process flows into the current semi-invariant of test tank and represents with F.Know that according to above-mentioned analysis the whole commutation process of commutator can be divided into and changes to/swap out two processes, these two processes are the opposite process of direction, so to change to/swap out in the whole process of commutator commutation be not in the same way.According to the course of work of commutator and the beginning and the finish time of timing, can obtaining commutator, to change to/swapping out in the process current semi-invariant that flows in the test tank be Q=A+B+G+E+F, and the timing time section is t 10-t 40, the average discharge that can obtain thus in the commutator commutation cycle is q=Q/ (t 4-t 1).Because the velocity flow profile of commutator nozzle segment is inhomogeneous and commutator changes to/swaps out not in the same way, causing above-mentioned flow is not actual flow in the commutator commutation cycle interior conduit, and ducted actual flow should be q 1=(B+C+G+D+E)/(t 4-t 1).Make q=q 1, must have: A+B+G+E+F=B+C+G+D+E, i.e. A+F=C+D.Satisfy A+F=C+D, must adjust the trigger action position of timer according to velocity flow profile.In fact, flow is not simultaneously, the flow rate of water flow of commutator nozzle ejection distributes also different, if the trigger action position is adjusted and is placed place, a fixed position according to the velocity flow profile under a certain flow, then the uncertainty that commutator causes under this flow will be less, and under other flow, the uncertainty that velocity flow profile and trigger action position cause commutator to cause will increase greatly, the mode of constantly adjusting the trigger action position according to different flow does not have feasibility again, therefore this commutator is difficult to realize A+F=C+D, so average discharge that obtains in the one-period that commutator changes to/swaps out and actual flow have than mistake, this just brings bigger uncertainty to device.Want to solve preferably the open type commutator and " change to/swap out " the big problem of the uncertainty of not bringing in the same way, more feasible way makes the open type commutator " change to/swap out in the same way " exactly.
Summary of the invention
The purpose of this invention is to provide commutator and commutation method thereof in the water flow standard apparatus that a kind of the realization " change to/swap out in the same way ".
For achieving the above object, the technical solution used in the present invention is: the commutator in this water flow standard apparatus mainly comprises the commutation nozzle, first shunt, the first commutation runner, the second commutation runner, the commutator timing guide rod and the photoelectric commutator of mutual coupling, commutator timing guide rod is fixedlyed connected with first shunt, and, below the first commutation runner and the second commutation runner, also be provided with second shunt, be provided with the first shunting chamber of mutual isolation in this second shunt, the measurement chamber and the second shunting chamber, the described first shunting chamber and the second shunting chamber lay respectively at the both sides of measurement chamber, described measurement chamber, the first shunting chamber and the second shunting chamber are equipped with water inlet and water delivering orifice, described measurement chamber, the water inlet in the first shunting chamber and the second shunting chamber is corresponding with the water delivering orifice of the first commutation runner and/or the second commutation runner respectively, and the water delivering orifice of measurement chamber is located at the bottom of this measurement chamber.
Further, the measurement chamber of second shunt of the present invention is funnel type.
Use the method that above-mentioned commutator of the present invention commutates mainly to comprise the steps:
1) moves horizontally first shunt, make the current of commutation nozzle ejection flow into the first shunting funnel of first shunt and enter the first commutation runner by first guide wire;
2) move horizontally second shunt, the water inlet and second water delivering orifice that commutates runner that make first water delivering orifice that commutates runner aim at the first shunting chamber of second shunt are aimed at the water inlet of the measurement chamber of second shunt, and the current in the first commutation runner are shunted the chamber through first thus and flowed into circulating water pool;
3) move horizontally first shunt, make the current of commutation nozzle ejection flow into the second shunting funnel of first shunt and flow into the measurement chamber of second shunt by second guide wire and the second commutation runner, the water delivering orifice by the measurement chamber bottom enters test tank again; When first shunt moved horizontally, this first shunt drove the motion of commutator timing guide rod, commutator timing guide rod is cooperated with photoelectric commutator with the control timer pick up counting;
4) move horizontally second shunt, make the water delivering orifice of the first commutation runner aim at the water inlet of described measurement chamber;
5) move horizontally first shunt, make the current of commutation nozzle ejection flow into the first shunting funnel and flow into the measurement chamber of second shunt by first guide wire and the first commutation runner, the water delivering orifice by the measurement chamber bottom enters test tank again;
6) move horizontally second shunt, make second water delivering orifice that commutates runner aim at the water inlet in the second shunting chamber of second shunt;
7) move horizontally first shunt, after making the current inflow second shunting funnel of commutation nozzle ejection and flowing into the second shunting chamber of second shunt by second guide wire and the second commutation runner, flow into circulating water pool again; When first shunt moves horizontally, drive the motion of commutator timing guide rod, commutator timing guide rod is cooperated with photoelectric commutator with the control timer stop timing.
Compared with prior art, the invention has the beneficial effects as follows: the present invention has not only overcome the defective that " pants " formula open type commutator " changes to/swaps out not in the same way " in the prior art, the more important thing is by realizing commutator " changing to/swap out in the same way ", reduce the uncertainty that the commutator commutation causes greatly, improved the accuracy of measurement of water flow standard apparatus.
Description of drawings
Fig. 1 is the structural representation of " pants " formula open type commutator in the prior art;
Fig. 2 is the commutation flow illustraton of model of " pants " formula open type commutator;
Fig. 3 is the structural representation of commutator of the present invention;
Fig. 4 is the commutation flow illustraton of model of commutator of the present invention;
Fig. 5~Figure 10 is the commutation process synoptic diagram of commutator of the present invention.
Embodiment
The present invention is the further improvement of doing on the basis of existing " pants " formula open type commutator.As shown in Figure 3, different with existing " pants " formula open type commutator is, below the first commutation runner 31 and the second commutation runner 32, also be provided with second shunt 6, be provided with the first shunting chamber 61 of mutual isolation in this second shunt 6, the measurement chamber 63 and the second shunting chamber 62, and the first shunting chamber 61 and the second shunting chamber 62 lay respectively at the both sides of measurement chamber 63, measurement chamber 63, the first shunting chamber 61 and the second shunting chamber 62 are equipped with water inlet and water delivering orifice, measurement chamber 63, the water inlet in the first shunting chamber 61 and the second shunting chamber 62 is corresponding with the water delivering orifice of the first commutation runner 31 and the second commutation runner 32 respectively.The water delivering orifice of measurement chamber 63 is located at the bottom of this measurement chamber, and is designed to funnel type, and this design helps current to flow into test tank more swimmingly.
When using commutator of the present invention, can be with commutation nozzle 1, first shunt 2, the first commutation runner 31, the second commutation runner 32, commutator timing guide rod 4, photoelectric commutator 5 is connected on support and with corresponding outlet conduit in the water flow standard apparatus as an overall fixed, wherein first shunt 2 moves by the air operated reversing valve controlling and driving, moving of first shunt 2 will drive 4 motions of commutator timing guide rod simultaneously, and commutator timing guide rod 4 is matched with photoelectric commutator 5 produce timing control signal, the beginning and the end of this timing control signal control timer.Second shunt, 6 safeties are contained on the guide rail and by stepper motor and move horizontally driving.The concrete course of work is as follows:
1) as shown in Figure 5, moves horizontally first shunt 2, make the current of commutation nozzle 1 ejection flow into the first shunting funnel 21 of first shunt 2 and enter the first commutation runner 31 by first guide wire 211.
2) as shown in Figure 6, move horizontally second shunt 6, the water inlet and second water delivering orifice that commutates runner 32 that make first water delivering orifice that commutates runner 31 aim at the first shunting chamber 61 of second shunt 6 are aimed at the water inlet of the measurement chamber 63 of second shunt 6, and the current in the first commutation runner 31 are shunted chamber 61 through first thus and flowed into circulating water pools.
3) as shown in Figure 7, move horizontally first shunt 2, the current that commutation nozzle 1 is sprayed flow into the second shunting funnel 22 of first shunt 2 and pass through second guide wire 222 and the measurement chamber 63 of the second commutation runner, 32 inflows, second shunt 6, and the water delivering orifice by measurement chamber 63 bottoms enters test tank again; When first shunt 2 moved horizontally, this first shunt 2 drove 4 motions of commutator timing guide rod, made commutator timing guide rod 4 cooperate output one pulse signal to pick up counting with the control timer with photoelectric commutator 5.
4) as shown in Figure 8, move horizontally second shunt 6, make the water delivering orifice of the first commutation runner 31 aim at the water inlet of described measurement chamber 63.
5) as shown in Figure 9, move horizontally first shunt 2, the current that commutation nozzle 1 is sprayed flow into the first shunting funnel 21, and pass through the measurement chamber 63 of first guide wire 211 and the first commutation runner, 31 inflows, second shunt 6, and the water delivering orifice by measurement chamber 63 bottoms enters test tank again.Timer does not stop timing in this step.
6) as shown in figure 10, move horizontally second shunt 6, make second water delivering orifice that commutates runner 32 aim at the water inlet in the second shunting chamber 62 of second shunt 6.
7) move horizontally first shunt 2, make the current of commutation nozzle 1 ejection flow into the second shunting funnel 22 and flow into the second shunting chamber 62 of second shunt 6 by second guide wire 222 and the second commutation runner 32 after, flow into circulating water pool again; When first shunt 2 moves horizontally, drive 4 motions of commutator timing guide rod, make commutator timing guide rod 4 cooperate output one pulse signal to stop timing with photoelectric commutator 5 with the control timer.
The said structure of commutator of the present invention and corresponding work process thereof have realized that the timing of commutator begins (step 3) of the corresponding above-mentioned course of work) and timing end (step 7) of the corresponding above-mentioned course of work) is finished at same direction same position place, have realized that promptly commutator " changes to/swap out in the same way ".Commutation discharge model shown in Figure 4 is a reverser assembly commutation process corresponding flow model of the present invention.Can know by Fig. 4, because this discharge model is " changing to/swap out in the same way " model, so realized A=D, C=F, A+F=C+D, overcome the A+F=C+D problem that " pants " formula open type commutator is difficult to realize, realized finally that therefore the interior average discharge of timing time section of a commutation cycle of commutator equates with actual flow: q 1=(B+C+G+D+E)/(t 4-t 1)=(A+B+G+E+F)/(t 4-t 1)=q.

Claims (3)

1. the commutator in the water flow standard apparatus, comprise commutation nozzle (1), first shunt (2), the first commutation runner (31), the second commutation runner (32), the commutator timing guide rod (4) and the photoelectric commutator (5) of mutual coupling, commutator timing guide rod (4) is fixedlyed connected with first shunt (2), it is characterized in that: the below at the first commutation runner (31) and the second commutation runner (32) also is provided with second shunt (6), be provided with the first shunting chamber (61) of mutual isolation in this second shunt (6), the measurement chamber (63) and the second shunting chamber (62), the described first shunting chamber (61) and the second shunting chamber (62) lay respectively at the both sides of measurement chamber, described measurement chamber, the first shunting chamber and the second shunting chamber are equipped with water inlet and water delivering orifice, described measurement chamber, the water inlet in the first shunting chamber and the second shunting chamber is corresponding with the water delivering orifice of the first commutation runner (31) and/or the second commutation runner (32) respectively, and the water delivering orifice of measurement chamber (63) is located at the bottom of this measurement chamber.
2. the commutator in the water flow standard apparatus according to claim 1 is characterized in that: the measurement chamber of described second shunt (6) is funnel type.
3. the method that the commutator that uses claim 1 commutates is characterized in that comprising the steps:
1) moves horizontally first shunt (2), make the current of commutation nozzle (1) ejection flow into the first shunting funnel (21) of first shunt (2) and enter the first commutation runner (31) by first guide wire (211);
2) move horizontally second shunt (6), the water inlet and second water delivering orifice that commutates runner (32) that make first water delivering orifice that commutates runner (31) aim at the first shunting chamber (61) of second shunt (6) are aimed at the water inlet of the measurement chamber (63) of second shunt (6), and the current in the first commutation runner (31) are shunted chamber (61) through first thus and flowed into circulating water pool;
3) move horizontally first shunt (2), the current that commutation nozzle (1) is sprayed flow into the second shunting funnel (22) of first shunt (2) and pass through second guide wire (222) and the measurement chamber (63) of second commutation runner (32) inflow second shunt (6), and the water delivering orifice by measurement chamber (63) bottom enters test tank again; When first shunt (2) moved horizontally, this first shunt (2) drove commutator timing guide rod (4) motion, commutator timing guide rod (4) is cooperated with photoelectric commutator (5) with the control timer pick up counting;
4) move horizontally second shunt (6), make first water delivering orifice that commutates runner (31) aim at the water inlet of described measurement chamber (63);
5) move horizontally first shunt (2), make the current of commutation nozzle (1) ejection flow into the first shunting funnel (21) also flows into second shunt (6) by first guide wire (211) and the first commutation runner (31) measurement chamber (63), the water delivering orifice by measurement chamber (63) bottom enters test tank again;
6) move horizontally second shunt (6), make second water delivering orifice that commutates runner (32) aim at the water inlet in the second shunting chamber (62) of second shunt (6);
7) move horizontally first shunt (2), after making the current inflow second shunting funnel (22) and the second shunting chamber (62) of commutation nozzle (1) ejection, flow into circulating water pool again by second guide wire (222) and second commutation runner (32) inflow second shunt (6); When first shunt (2) moves horizontally, drive commutator timing guide rod (4) motion, commutator timing guide rod (4) is cooperated with photoelectric commutator (5) with the control timer stop timing.
CN2010101095937A 2010-02-11 2010-02-11 Commutator of water flow standard device and commutation method thereof Expired - Fee Related CN101788323B (en)

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Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102141426B (en) * 2010-12-07 2012-11-07 浙江省计量科学研究院 Fluid reversing device and reversing and timing method
CN102331283A (en) * 2011-08-08 2012-01-25 天津大学 Swing splitter plate type commutator driven by stepping motor
CN103438964B (en) * 2013-09-09 2016-01-20 中国计量科学研究院 A kind of hermetic type open commutator
CN107131930B (en) * 2017-06-06 2019-11-22 浙江省计量科学研究院 A kind of type open type fluid switching device in the same direction and the method for fluid switching and timing
CN109579952B (en) * 2019-01-28 2020-09-08 中国计量科学研究院 Commutator nozzle with adjustable opening degree
CN111707334B (en) * 2020-05-15 2022-12-06 浙江水利水电学院 Rotary open type equidirectional commutator in liquid flow standard device and method thereof

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4490077A (en) * 1981-07-28 1984-12-25 Nippon Kokan Kabushiki Kaisha Apparatus for continuously measuring flow rate of fine material flowing through transport pipe
CN201060035Y (en) * 2007-07-10 2008-05-14 兰州市供水(集团)有限公司 Commutalor with adjustable stroke speed and time difference
CN201352143Y (en) * 2009-01-16 2009-11-25 朱家顺 Full closed open commutator
CN201622100U (en) * 2010-02-11 2010-11-03 浙江省计量科学研究院 Commutator in water flow standard device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4490077A (en) * 1981-07-28 1984-12-25 Nippon Kokan Kabushiki Kaisha Apparatus for continuously measuring flow rate of fine material flowing through transport pipe
CN201060035Y (en) * 2007-07-10 2008-05-14 兰州市供水(集团)有限公司 Commutalor with adjustable stroke speed and time difference
CN201352143Y (en) * 2009-01-16 2009-11-25 朱家顺 Full closed open commutator
CN201622100U (en) * 2010-02-11 2010-11-03 浙江省计量科学研究院 Commutator in water flow standard device

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