A kind of digital display air pump and the accurate method that obtains to be inflated device air pressure
Technical field
The present invention relates to inflate technical field, relate in particular to a kind of digital display air pump and the accurate method that obtains to be inflated device air pressure.
Background technique
Air pump is a kind of accessory commonly used on the automobile, and it drives air compressor through electric power and produces air pressure and be inflated device to give, for example inflation such as tire.In the using process of air pump; In order to understand the air pressure situation that is inflated device; Prevent that hyperinflation from causing being inflated the device explosion; Usually connect baroceptor at the air compressor output terminal, rough calculation goes out to be inflated the air pressure of device through the air pressure that detects the air compressor output terminal, and through display unit this atmospheric pressure value is shown.
Yet because air compressor is connected by tracheae with being inflated between the device; There is variation in tracheae length; Also there is the difference whether valve inside is arranged in the place, gas access that is inflated device; During the air pressure change in being inflated device, the motor speed that drives air compressor also changes thereupon simultaneously; The all feasible complicacy that becomes to the relation that is inflated the atmospheric pressure value between the device from baroceptor of above-mentioned factor; Thereby when making air pump work, display unit can not accurately estimate the atmospheric pressure value of tire or other pressure vessels according to the atmospheric pressure value that baroceptor detects.
Summary of the invention
Technical problem to be solved by this invention is, to the above-mentioned deficiency of existing technology, proposes a kind of ability precise real-time and shows the digital display air pump that is inflated the device atmospheric pressure value.
The technological scheme that the present invention solves its technical problem employing is to propose a kind of digital display air pump, and it comprises
The direct current load module is used to receive the outside direct current of importing;
Direct current motor, air compressor; Said direct current motor drives air compressor work and is inflated the device inflation to give, and said being inflated between device and the air compressor is connected through tracheae;
Baroceptor is connected in air compressor and is inflated and is used to detect air compressor between the device and is inflated the sampling atmospheric pressure value between the device;
Control module is used to receive the sampling atmospheric pressure value of baroceptor output and export accurate atmospheric pressure value after treatment to display modular;
Said control module is handled the sampling atmospheric pressure value to obtain accurate atmospheric pressure value through following mode:
When air pump does not start, the first sampling atmospheric pressure value P11 of record baroceptor; At this moment, being inflated the first inner actual pressure value P21 of device equates with the first sampling atmospheric pressure value P11;
In 3 to 10 seconds, write down the second sampling atmospheric pressure value P12 of baroceptor after air pump starts, and obtain direct current motor first rotation speed n according to the period of change of baroceptor sampling air pressure
1
The real-time change cycle according to baroceptor sampling air pressure draws the real-time rotation speed n of direct current motor, and detects real-time sampling atmospheric pressure value P through baroceptor, according to formula P '=((P12-P11) * P12*n
2* P)/(n
1 2) draw and be inflated the accurate atmospheric pressure value P ' of device.
Further, said control gear is single-chip microcomputer, dsp chip or PLC.
Further, said display unit is LED nixie tube or liquid crystal display panel.
Further, said digital display air pump also comprises the break-make control module that is arranged between direct current load module and the direct current motor, and said break-make control module is electrically connected on control module, is used for the break-make control signal break-make according to control module output; Be electrically connected on the load module of control module, input to control module in order to will set atmospheric pressure value; Said control module is relatively set atmospheric pressure value and is inflated the accurate atmospheric pressure value of device, when the accurate atmospheric pressure value that is inflated device when setting atmospheric pressure value, control module makes the conducting of break-make control module; When the accurate atmospheric pressure value that is inflated device when setting atmospheric pressure value, control module makes the break-make control module break off.
Further, said load module is button or touch screen.
Further, said break-make control module adopts metal-oxide-semiconductor as control gear.
The present invention also provides a kind of accurate acquisition to be inflated the method for device air pressure, and it comprises step:
S1: the first sample voltage value P11 when not starting through the baroceptor detection;
S2: in 3 to 10 seconds, detect the second sampling atmospheric pressure value P12 after starting, and draw direct current motor first rotation speed n according to the period of change of baroceptor sampling air pressure through baroceptor
1
S3: after starting fully, draw the real-time rotation speed n of direct current motor according to real-time change cycle of baroceptor sampling air pressure, and detect real-time sampling atmospheric pressure value P, according to formula P '=((P12-P11) * P12*n through baroceptor
2* P)/(n
1 2) draw and be inflated the accurate atmospheric pressure value P ' of device.
The present invention makes that through the detected sampling air pressure of special processing baroceptor in control module the real-time atmospheric pressure value that is inflated device of control module output is more accurate, makes things convenient for the user to judge.The present invention simultaneously makes the user need not to wait for by air pump through the break-make control module is set, and when the real-time air pressure that is inflated device reaches preset atmospheric pressure value ability automatic disconnection air compressor, saves manpower and man-hour.
Description of drawings
Fig. 1 is the circuit theory schematic representation of digital display air pump first preferred embodiment of the present invention;
Fig. 2 is in one embodiment of the invention, the variation oscillogram of baroceptor sampling air pressure;
Fig. 3 is the circuit theory schematic representation of digital display air pump second preferred embodiment of the present invention.
Embodiment
Below be specific embodiment of the present invention and combine accompanying drawing, technological scheme of the present invention is done further to describe, but the present invention is not limited to these embodiments.
Please with reference to Fig. 1, Fig. 1 is the circuit theory schematic representation of digital display air pump first preferred embodiment of the present invention.Among Fig. 1, digital display air pump comprises direct current load module 1, is used to receive the direct current of outside input; Direct current motor 2, air compressor 3, direct current motor 2 drive air compressors 3 work and are inflated device 4 inflations to give, and are inflated between device 4 and the air compressor 3 to be connected through tracheae 5; Baroceptor 6 is connected in air compressor 3 and is inflated and is used to detect air compressor 3 between the device 4 and is inflated between the device 4 sampling atmospheric pressure value; Control module 7 is used to receive the sampling atmospheric pressure value of baroceptor 6 outputs and export accurate atmospheric pressure value to display modular 8 after treatment.
Control module is handled the sampling atmospheric pressure value in the following way to obtain accurate atmospheric pressure value among the present invention:
When (1) air pump does not start, the first sampling atmospheric pressure value P11 of record baroceptor 6; At this moment, being inflated the device 4 first inner actual pressure value P21 equates with the first sampling atmospheric pressure value P11;
(2) in 3 to 10 seconds, the sampling atmospheric pressure value of baroceptor 6 was changed to the second sampling atmospheric pressure value P12, and because the time is shorter, is inflated device 4 inner actual pressure values also not change, and still is P21 after air pump started.Obtain baroceptor 6 sampling atmospheric pressure values and the difference DELTA P=P12-P11 that is inflated device 4 inner actual pressure values this moment.
(3) start in back 3 to 10 seconds at air pump, the period of change of sampling air pressure according to baroceptor 6 draws direct current motor 2 first rotation speed n
1
In one embodiment, the variation oscillogram of baroceptor 6 sampling air pressure is as shown in Figure 2.Among Fig. 2, in the variation waveform of sampling air pressure, each cycle comprises 3 crests, and each cycle representes that promptly direct current motor 2 rotates a circle, and also is a gas replenishment process of air compressor 3.The time of sampling pressure change waveform one-period is T, promptly represents direct current motor 2 to rotate a circle and needs time spent T, can obtain direct current motor 2 first rotation speed n in view of the above
1
(4) can know baroceptor 6 sampling atmospheric pressure values and the difference DELTA P=K*n that is inflated device 4 inner actual pressure values according to the basic principle of fluid mechanics and Electrical Motor
1* n
1/ P.The atmospheric pressure value that on behalf of baroceptor 6, P sample, K are scaling factor.With this formula substitution Δ P=P12-P11, can get P12-P11=K*n
1* n
1/ P12, can obtain the concrete numerical value of scaling factor K, K=[(P12-P11) * P12]/(n this moment
1* n
1).
(5) baroceptor 6 is in sampling process, and its real-time sampling atmospheric pressure value is designated as P, and the direct current motor 2 real-time rotating speeds that obtain according to step (3) are n, and the accurate atmospheric pressure value P ' that can obtain being inflated device this moment is:
P’=((P12-P11)*P12*n
2*P)/(n
1 2);
Control module 7 should accurate atmospheric pressure value P ' exports display modular 8 to and can make things convenient for the user to recognize in real time to be inflated device 4 atmospheric pressure value accurately.
In order to save manpower, make the user need not when air-pump inflating, to wait for to be inflated device whether be full of in the other Real Time Observation of air pump, the present invention also provides second preferred embodiment.As shown in Figure 3, Fig. 3 is the circuit theory schematic representation of digital display air pump second preferred embodiment of the present invention.Be with the difference of first preferred embodiment; Be connected with break-make control module 9 between direct current load module 1 and the direct current motor 2 in second preferred embodiment; Break-make control module 9 is electrically connected on control module 7; Be used for break-make control signal break-make according to control module 7 outputs, thus the break-make of control direct current motor 2.Also comprise load module 10, load module 10 is used for will setting atmospheric pressure value according to user's setting and inputs to control module 7.
Control module 7 is relatively set atmospheric pressure value and is inflated the accurate atmospheric pressure value P ' of device, when the accurate atmospheric pressure value P ' that is inflated device 6 when setting atmospheric pressure value, control module 7 makes 9 conductings of break-make control module; When the accurate atmospheric pressure value P ' that is inflated device 6 when setting atmospheric pressure value, control module 7 makes break-make control module 9 break off.
When adopting this kind control mode, the user need not to wait for by air pump, can automatic disconnection motor and air compressor after being inflated device internal air pressure value to reach the setting atmospheric pressure value.
Further, in the present embodiment, the break-make control module adopts metal-oxide-semiconductor as control gear.
Load module can be button, touch screen or other input devices.
But control module single-chip microcomputer, dsp chip or PLC etc. are as control gear.
The present invention also provides a kind of accurate acquisition to be inflated the method for device air pressure, and it comprises step:
S1: the first sample voltage value P11 when not starting through the baroceptor detection; At this moment, being inflated the first inner actual pressure value P21 of device equates with the first sampling atmospheric pressure value P11;
S2: in 3 to 10 seconds, detect the second sampling atmospheric pressure value P12 after starting, and draw direct current motor first rotation speed n according to the period of change of baroceptor sampling air pressure through baroceptor
1
S3: after starting fully, draw the real-time rotation speed n of direct current motor according to real-time change cycle of baroceptor sampling air pressure, and detect real-time sampling atmospheric pressure value P, according to formula P '=((P12-P11) * P12*n through baroceptor
2* P)/(n
1 2) draw and be inflated the accurate atmospheric pressure value P ' of device.
Specific embodiment described herein only is that the present invention's spirit is illustrated.Person of ordinary skill in the field of the present invention can make various modifications or replenishes or adopt similar mode to substitute described specific embodiment, but can't depart from spirit of the present invention or surmount the defined scope of appended claims.