CN201364341Y - Fan speed measuring device - Google Patents

Abstract

The utility model provides an electric motorcar charger fan measuring device, and the technical scheme is that the first output end of a sensor is connected with the first input end of a signal amplifier, the second output end of the sensor is connected with the input end of the set voltage circuit, the output end of the signal amplifier is connected with the input end of a detector, the output end of the set voltage circuit is connected with the second input end of the signal amplifier, and the output end of the detector is connected with the input end of a display; the sensor transmits the received fan rotating speed signal to the signal amplifier, which is transmitted to the detector after being compared and amplified by the set voltage circuit, then is transmitted to the display after being detected and screened by the detector, and the display shows whether the fan is qualified according to the degree of the input signal. The device provides a simple measuring method and can carry out measurement in line with the production line.

Description

The fan speed measuring device

Technical field

The utility model relates to battery charger, especially the electric motor car battery charger.

Background technology

The classic method of measuring rotation speed of the fan at present has: 1, mechanical rpm tachometric survey; 2, stroboscopic rpm tachometric survey; 3, laser rpm tachometric survey.First kind of mechanical measurement belongs to contact type measurement, requires equipment under test rotating speed and torque to be much higher than the error range of surveying instrument.The two kinds of methods in back are that stroboscopic rpm, laser rpm tachometric survey are noncontact optical measurement, though the degree of accuracy that tests the speed is higher, require also high to measuring condition, environment for use.For example, during laser measurement, laser must be aimed at the blade of fan, and for guaranteeing measuring accuracy, the page or leaf sheet must stick reflecting strips.Because the production line workload is very big, fan has the protection barrier outward again, must avoid barrier at every turn when the operator measures and aim at fan blade, shows when each operating process costs 1-2 minute in the practical operation, and efficiency of measurement is extremely low, and production cost strengthens.

The utility model content

The utility model aim to provide a kind of measuring method simple, can with the high efficiency electric motor car battery charger fan speed measuring device of production line synchro measure.

The technical solution of the utility model is: comprise sensor 1, signal amplifier 2, setting voltage circuit 3, detecting device 4, display 5 and power supply 6, first output terminal of sensor 1 is connected with the first input end of signal amplifier 2, second output terminal of sensor 1 links to each other with the input of setting voltage circuit 3, the output terminal of signal amplifier 2 is connected with the input of detecting device 4, the output of setting voltage circuit 3 is gone into end with second of signal amplifier 2 and is linked to each other, the output of detecting device 4 is connected with the input end of display 5, described sensor 1 reaches signal amplifier 2 with the fan rotating speed signals of being accepted, through setting voltage circuit 3 relatively, after the amplification, signal is delivered to detecting device 4, after device 4 detects screening after testing, signal is delivered to display 5, display 5 is made whether qualified demonstration according to the height of input signal, power supply 6 is described sensor 1, signal amplifier 2, setting voltage circuit 3, detecting device 4, display 5 provides working power, described sensor 1 is a Hall element, and described signal amplifier 2 is differential proportional amplifier.

Circuit block diagram is seen Fig. 1.

The fan speed measuring device made from technique scheme is used for electric motor car battery charger fan streamline check rotation speed of the fan, and measuring condition requires low, and method of operating is simple, can significantly enhance productivity.Because the workload of electric car charger production line every day is very big, fan has the protection barrier outward again, if take traditional measuring method, must avoid protecting barrier at every turn when the operator measures and aim at fan blade, when each operating process costs 1-2 minute, if every day, the wall scroll production line was produced thousands of, every running time requirement of having only 10 seconds, its efficient is extremely low, and production cost strengthens.Below tabulation is the comparison of this programme and traditional measurement method.

Speed-measuring method	Mode tests the speed	Operation easier	Measuring Time	8H split run output
					Machinery tests the speed	Contact	Generally	90 seconds	280
Optically measuring speeds	Contactless	Complicated	60 seconds	420
					Electromagnetism tests the speed	Contactless	Simply	1 second	28800

In the last table, 8H split run output refers to the output that promptly calculated 8 hours duty, 7 hours effective time in 25200 seconds; Measuring Time refers to measure a desk fan rotating speed required time.Producing 15000 electric car chargers every day with certain factory is example, supposes to have 5 streamlines, and the output of every streamline is 3000.Calculate by 8 hours every days duty, 7 hours operational use times (25200 seconds), 3000=8.4 seconds/platform of 25200 seconds ÷, promptly be 8.4 seconds every index detection time of every charger.If survey rotation speed of the fan photographically, single only measure this every needs of rotating speed words of 60 seconds (1 minute), every day, every production line can only be produced: 7 hours * 60 minutes * 1 minute/platform=420, efficiency ratio is: 3000 ÷ 420=7.14, promptly the relative this programme of the cost of labor of separate unit need increase about 7 times.

Description of drawings

Fig. 1 is a fan measurement mechanism circuit block diagram.

Fig. 2 is a kind of circuit diagram of embodiment.

Embodiment

Specify below in conjunction with accompanying drawing.

As Fig. 2, after Hall element 1 receives the rotating magnetic field that the charger mini-fan sends, produce Hall voltage Uh at 2,4 pin.Along with the variation of rotating magnetic field under the different rotating speeds condition, Hall voltage Uh is also changing.The rated speed of supposing mini-fan is 3000 commentaries on classics, and at this moment, Uh voltage is 36mV.By experiment, be used for rotation speed of the fan noise minimum when 2600 ± 100 change of charger, at this moment, Uh voltage is 28mV ± 2mV.

Reference voltage 3 preestablishes the intrinsic standoff ratio of R9 and R11 by the bleeder circuit of forming of resistance R 9 with R11, determines the reference comparison voltages of amplifier 3 pin.This comparative voltage is exactly the Hall voltage that is produced behind the fan reduction of speed.Supply voltage as testing apparatus is 5V, R11=100K, and R9=150 Ω is according to intrinsic standoff ratio $\frac{0.15}{0.15+100}\×5V=7.5\mathrm{mV},$ The 3 pin voltages of IC1 are about 7.5mV.Induced signal amplifies the rear drive late-class circuit through the differential proportional amplifier 2 that IC1 forms, and amplifies the about 150mV of 1 pin signal voltage of back IC1.

It is testing circuit 4 that IC2 and peripheral devices have constituted Schmitt trigger circuit.Whether the comparison signal that has amplified utilizes the return difference characteristic of Schmidt circuit, judge rotation speed of the fan and meet the requirements, and shows with LED by display 5 when meeting the rotating speed requirement.

Claims (3)

1, a kind of fan speed measuring device, it is characterized in that comprising: sensor (1), signal amplifier (2), setting voltage circuit (3), detecting device (4), display (5) and power supply (6), first output terminal of sensor (1) is connected with the first input end of signal amplifier (2), second output terminal of sensor (1) links to each other with the input of setting voltage circuit (3), first output terminal of signal amplifier (2) is connected with the input of detecting device (4), the output terminal of setting voltage circuit (3) links to each other with second input end of signal amplifier (2), the output terminal of detecting device (4) is connected with the input end of display (5), described sensor (1) reaches signal amplifier (2) with the fan rotating speed signals of being accepted, through setting voltage circuit (3) relatively, after the amplification, signal is delivered to detecting device (4), after device (4) detects screening after testing, signal is delivered to display (5), display (5) is made whether qualified demonstration according to the height of input signal, and power supply (6) is described sensor (1), signal amplifier (2), setting voltage circuit (3), detecting device (4), display (5) provides working power.

2, fan speed measuring device according to claim 1 is characterized in that described sensor (1) is a Hall element.

3, fan speed measuring device as claimed in claim 1 or 2 is characterized in that described amplifier (2) is differential proportional amplifier.

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