Background technology
Detect water temperature, control water temperature, be people in life and in producing modal technological means it-.The water cooling system of high power broadcast transmitter, radar transmitter, the chilled water of water dispenser, water heater, internal combustion engine (such as motor car engine) etc., the technological means of all will adopting and detect water temperature, controlling water temperature.
Detect water temperature or control water temperature, must use temperature sensor (Temperature sensor).Due to the ubiquity of temperature detection, the use amount of temperature sensor height in various sensors ranks first.
High end equipment is the water cooling system of radar transmitter for example, the temperature sensor of following type commonly used: thermistor temperature sensor is MF53-1, platinum resistance Pt100 temperature sensor, integrated simulation temperature sensor AD590, integrated digital temperature sensor MAX6575 for example for example for example; Easy equipment for example water dispenser generally adopts Kick type bimetallic strip (for example KSD301) to make temperature sensor.
Above-mentioned temperature sensor, precision all can meet the control requirement of place equipment, but the following great technological deficiency of ubiquity: thermal inertia is large, the response time is long!
Described MF53-1, Pt100, AD590, MAX6575 equitemperature sensor, for the sensing water temperature, must for example, on the basis of original encapsulation (the original encapsulation of MF53-1 and conventional, electric-resistance device are approximate, AD590 identical with the triode profile), encapsulate again, again packing forms-as be: the shell metal material, shell Inner fill insulant is epoxy resin for example.As everyone knows, insulating material is hot poor conductor, due to the heat-blocking action of insulating material, just makes described temperature sensor " thermal inertia is large, the response time is long " (hereinafter to be referred as thermal time constant).
The defect of temperature sensor " thermal inertia is large, thermal time constant is long ", can affect the performance of its place equipment in many occasions.For example, in Power Solid-state Radar Transmitter, 10 ℃ of the every increases of the junction temperature of power transistor, its reliability 60 ℅ that just will descend.The Kick type bimetallic strip that water dispenser generally adopts (for example KSD301), be attached on the Water heating vessel of water dispenser wall, and the time of its temperature-sensitive is longer.
The thermal inertia of the infrared temperature-test sensor progressively used in recent years is almost nil, but such as the water in water dispenser, be still all to be enclosed within container (or pipeline) such as the radar chilled water, infrared temperature-test sensor can only be surveyed the wall temperature of water container, and conducting to chamber wall, water temperature needs conduction time, chamber wall can dispel the heat and can not truly reflect the water temperature in container simultaneously, therefore, use expensive infrared temperature-test sensor to solve the problem of " thermal inertia is large, thermal time constant is long " in essence ground.
The defect existed for prior art, the target that the present invention will reach is: utilize the characteristic of the noise signal in water, design-kind of " the noise-type water temperature controling circuit " that can detect real-time temperature and water temperature be carried out to instant automatic control.
invention Inner holds
As everyone knows, water except pure water, for example tap water, river, industry or sanitary sewage are all the material (chilled waters of radar transmitter with certain conductive capability, although be through purified treatment, resistivity is higher, but be not that " pure water " still has certain conductive capability), it contains the multiple charged corpuscles such as ion, aqueous electron (hydrated elecctron or eaq).The effects such as these charged corpuscles are heated, light, electromagnetic field, can produce the multiple noises such as thermonoise, Johnson noise, flicker noise.According to methods such as " theory of probability " and thermodynamics statistical theories, can prove, the noise in water be power spectrum density evenly, with the white noise of frequency-independent, its voltage mean square value is Un
2=4KTRB ... (1)
(1) in formula: K is Boltzmann constant: 1.38 * 10
-23joule/degree (absolute temperature);
The temperature that T is water, measure with absolute temperature;
The equivalent resistance that R is water;
The passband that B is testing apparatus.
(1) formula shows, has the noise voltage that numerical value is Un in described water, and, the mean square value Un of this noise voltage Un
2to water temperature T (absolute temperature), be directly proportional.Can show intuitively this noise voltage Un with oscillograph, Fig. 1 is the noise audiogram of District of Shanghai tap water when room temperature is 32 ℃.
Described noise voltage Un(is hereinafter referred to as noise signal Un) feature be:
1, synchronize and change with water temperature, its mean square value Un
2to water temperature T (absolute temperature), be directly proportional;
2,, without thermal inertia, thermal time constant (thermal response time) is zero;
If 3 as control signal, can realize " instant control " to water temperature.
The present invention is exactly a kind of device that utilizes described noise signal Un to realize water temperature is controlled automatically.
The present invention is comprised of container (or pipeline) AV, ground-electrode AE, sensing electrode AK, coupling capacitance C3, amplifying circuit 20, detecting circuit 30, temperature setting circuit 40, executive circuit 50 and direct supply 10; Described sensing electrode AK, coupling capacitance C3, amplifying circuit 20, detecting circuit 30, temperature setting circuit 40, executive circuit 50 are connected successively; Described ground-electrode AE, amplifying circuit 20, detecting circuit 30, temperature setting circuit 40, executive circuit 50 equal link ground; Described direct supply 10 provides DC voltage Uc for described amplifying circuit 20, executive circuit 50; The negative pole of described DC voltage Uc is connected with circuit ground.
If described container AV adopts metal to make and, by its link ground, described ground-electrode AE can omit;
Described sensing electrode AK obtains from the water of container AV synchronizes the noise signal Un without thermal inertia changed with water temperature, this noise signal Un carries out instant control automatically as (be " system " hereinafter referred to as the present invention) control signal of system to water temperature.
Described noise signal Un delivers to executive circuit 50 through coupling capacitance C3 coupling, amplifying circuit 20 amplifications, detecting circuit 30 detections, temperature setting circuit 40 and carries out the instant program of controlling water temperature after setting ultimate temperature; Described temperature setting circuit 40 is pressed following program setting ultimate temperature:
Lower limit temperature Tmin: put water temperature in the described container AV lower limit temperature Tmin for needing, adjusting the second potentiometer RP2 in described temperature setting circuit 40, to make the voltage on integrated circuit (IC) 1 the 2nd pin in described executive circuit 50 be lower voltage limit U20;
Ceiling temperature Tmax: put water temperature in the container AV ceiling temperature Tmax for needing, adjusting the 6th potentiometer RP6 in described temperature setting circuit 40, to make the voltage on described integrated circuit (IC) 1 the 6th pin be upper voltage limit U60;
50 of described executive circuits are immediately automatically controlled water temperature by following program:
When water temperature T lower than smallest limit temperature T min is T<Tmin, the voltage U 2 on 2 pin of described integrated circuit (IC) 1 is U2<U20 lower than lower voltage limit, and the voltage U 3 of its 3 pin output is high level, and the performer relay J in executive circuit 50 obtains electric;
When water temperature T higher than ceiling temperature Tmax is T>Tmax, the voltage U 6 on 6 pin of described integrated circuit (IC) 1 is U6>U60 higher than upper voltage limit, and the voltage U 3 of its 3 pin output is low level, described relay J dead electricity.
Described relay J is switched on or switched off by its break contact DD or load RL and the AC220V of moving together contact DH control system:
If the well heater (heating device) of described load RL water: described relay J obtains when electric, and itself and AC220V connect, and water obtains hot intensification; During the relay J dead electricity, itself and AC220V disconnect, and water starts insulation;
If the refrigeration plant (refrigeration device) of described load RL water: during described relay J dead electricity, itself and AC220V connect, and water obtains cold cooling; Relay J obtains when electric, and itself and AC220V disconnect, and water starts insulation.
Go round and begin again, the present invention just automatically immediately controls water temperature T in described container (or pipeline) AV between lower limit temperature Tmin and ceiling temperature Tmax, controls water temperature T in the scope of Tmin<T<Tmax that is:.
Application the present invention can obtain following beneficial effect:
1, cheap and simple.Sensing arrangement of the present invention is very simple, cheap, need only in container (or pipeline) AV, sensing electrode AK be set, ground-electrode AE gets final product.If container (or pipeline) AV is metal, make, ground-electrode AE can omit, and container (or pipeline) AV need only be connected with the line-to-ground line.
2, instant control.Control signal of the present invention is noise signal Un in the water that obtains of sensing electrode AK, and as previously mentioned, this noise signal Un is directly related with water temperature T, and water temperature T rising or decline, noise signal Un just rise thereupon or descend, and do not have thermal inertia between the two.Or say: the thermal time constant of sensing arrangement of the present invention → 0 can be rated as the temperature sensor of " ideal ".Therefore, the present invention can for example, realize " the instant control " without thermal inertia to the water temperature of relevant device (water cooling system of high power broadcast transmitter).This " instant control " without thermal inertia mode is that prior art is difficult to the brand-new control mode realized.
3, dynamic range is large.In water, the value of noise signal Un changes in great dynamic range, and system all can work.
Embodiment
Below, by reference to the accompanying drawings, set forth the preferred embodiment of the present invention:
Fig. 2 is functional-block diagram of the present invention, the circuit theory diagrams that Fig. 3 is the preferred embodiment of the invention 1.In conjunction with Fig. 2, Fig. 3:
Transformer T, rectifier bridge BR, the first capacitor C 1, the second capacitor C 2, voltage stabilizing diode DW have formed direct supply 10, and the acting in conjunction of above-mentioned device, for amplifying circuit 20 of the present invention, executive circuit 50 provide DC voltage Uc.The anode of described DC voltage Uc is connected with amplifying circuit 20, executive circuit 50, negative terminal is connected with circuit ground.
The first resistance R 1, the second resistance R 2, the 3rd resistance R 3, the first triode V1, the second triode V2 have formed amplifying circuit 20.
The preferential complex pipe amplifier amplification noise signal Un formed by the first triode V1, the second triode V2 that adopts of the present invention, also can adopt other forms of amplifier for example integrated operational amplifier amplify described noise signal Un.
The 4th capacitor C 4, the first diode D1, the second diode D2, the 5th capacitor C 5, the 6th capacitor C 6 have formed detecting circuit 30.
The 4th resistance R 4, the 6th potentiometer RP6, the second potentiometer RP2 have formed temperature setting circuit 40, and, the travelling arm of described the 6th potentiometer RP6 (movable contact) is connected with 6 pin of integrated circuit (IC) 1 in executive circuit 50, and the travelling arm of the second potentiometer RP2 is connected with 2 pin of IC1.
In conjunction with Fig. 3: become the load of detecting circuit 30 after the 4th resistance R 4, the 6th potentiometer RP6, the second potentiometer RP2 and integrated circuit (IC) 1 connection in series-parallel, because the input impedance of integrated circuit (IC) 1 is very big, therefore, the load of detecting circuit 30 can be reduced to the equivalent resistance after the 6th potentiometer RP6, the 4th resistance R 4, the second potentiometer RP2 connection in series-parallel: RP6 ∥ (R4+RP2).One of the advantage of " temperature setting circuit 40 " that the present invention is designed is: no matter how the travelling arm of the 6th potentiometer RP6, the second potentiometer RP2 is regulated, and the equivalent load resistance of detecting circuit 30: RP6 ∥ (R4+RP2) all remains unchanged.This kind of design, increased stable, the reliability of detecting circuit 30 and amplifying circuit 20 significantly.
This temperature setting circuit 40 is pressed following program setting ultimate temperature:
Lower limit temperature Tmin: put water temperature in the container AV lower limit temperature Tmin for needing, adjusting the second potentiometer RP2, to make the voltage on integrated circuit (IC) 1 the 2nd pin be lower voltage limit U20=1/3Uc;
Ceiling temperature Tmax: put water temperature in the container AV ceiling temperature Tmax for needing, adjusting the 6th potentiometer RP6, to make the voltage on integrated circuit (IC) 1 the 6th pin be upper voltage limit U60=2/3Uc;
According to above-mentioned setting, refer again to the table Da formula Un of aforesaid noise voltage mean square value
2=4KTRB i.e. (1) formula, known:
When water temperature T lower than lower limit temperature Tmin is T<Tmin, voltage U 2<U20=1/3Uc is U2<1/3Uc;
When water temperature T higher than ceiling temperature Tmax is T>Tmax, voltage U 6>U60=2/3Uc is U6>2/3Uc.
Integrated circuit (IC) 1(model: time-base integrated circuit LM555) with its peripheral components: LED, relay J, the 3rd diode D3 and the 7th capacitor C 7 have formed executive circuit 50; And, 1 pin link ground of integrated circuit (IC) 1,2 pin connect the travelling arm of the second potentiometer RP2, and 6 pin connect the travelling arm of the 6th potentiometer RP6, and 4 pin all are connected with the anode of DC voltage Uc with 8 pin, and 5 pin are connected with the 7th capacitor C 7 on a termination circuit ground; Relay J is with after the 3rd diode D3 is in parallel ,-end (positive terminal of the 3rd diode D3) link ground, another-as to hold to be connected with the negative pole of LED, and the positive pole of LED connects 3 pin of integrated circuit (IC) 1.
In conjunction with Fig. 3: according to the characteristic of time base circuit LM555, can be by the instant base circuit of integrated circuit (IC) 1(LM555) regard special R-S trigger as, in the present embodiment 1, it has following characteristics:
Its 5 pin is connected with the 7th capacitor C 7 on a termination circuit ground;
When the voltage U 2<U20 on its 2 pin is U2<1/3Uc, the voltage U 3 of its 3 pin output is high level;
When the voltage U 6>U60 on its 6 pin is U6>2/3Uc, the voltage U 3 of its 3 pin output is low level.
In conjunction with Fig. 2, Fig. 3: the course of work of the present embodiment 1 is: in the water that sensing electrode AK obtains, noise signal Un delivers to the control program of executive circuit 50 below carrying out through coupling capacitance C3 coupling, amplifying circuit 20 amplifications, detecting circuit 30 detections, temperature setting circuit 40 after setting:
1, heat up: when the water temperature T in container AV is T<Tmin lower than lower limit temperature Tmin, voltage U 2 on 2 pin of integrated circuit (IC) 1 is U2<U20 lower than lower voltage limit, the voltage U 3 of its 3 pin output is high level, the performer relay J obtains electric, its moving together contact (normally opened contact) DH closure, AC220V is applied to load RL two ends, simultaneously, LED is lighted, and indication load RL switches on.
If being the electricity in container AV, load RL heats for example electrothermal tube of device, after its energising, water temperature in container AV will progressively rise, and when water temperature T higher than ceiling temperature Tmax is T>Tmax, the voltage U 6 on 6 pin of integrated circuit (IC) 1 is U6>U60 higher than lower voltage limit, the voltage U 3 of its 3 pin output is low level, the relay J dead electricity, its moving together contact DH disconnection that resets, load RL outage stops heating, LED extinguishes, and indication load RL cuts off the power supply.
2, insulation:
Load RL outage stops heating, system just enters keeping warm mode, and water temperature will descend gradually.Work as water temperature T
Again, after dropping to T<Tmin, system is carried out " intensification " program again, circulation so again and again, and capable of controlling water temperature T between lower limit temperature Tmin and ceiling temperature Tmax, that is: controls water temperature T in the scope of Tmin<T<Tmax.
Performer in described executive circuit 50 is preferentially selected electromagnetic relay, also can select solid-state relay (Solid State Relays, SSR) or bidirectional thyristor (Triode AC Switch, TRIAC).
The present embodiment 1 is suitable to for example water temperature control of water dispenser, water heater of electric heater of paddling.
The circuit theory diagrams that Fig. 4 is embodiments of the invention 2, the principle of work of the present embodiment 2 is identical with embodiment 1, and difference has:
One, DC voltage U5 replaces capacitor C 7 to have accessed integrated circuit (IC) 1 is 5 pin of time-base integrated circuit LM555.
After doing design like this, the present embodiment 2 is just by following program setting ultimate temperature:
Lower limit temperature Tmin: put water temperature in the container AV lower limit temperature Tmin for needing, adjusting the second potentiometer RP2, to make the voltage on integrated circuit (IC) 1 the 2nd pin be lower voltage limit U20=1/2U5;
Ceiling temperature Tmax: put water temperature in the container AV ceiling temperature Tmax for needing, adjusting the 6th potentiometer RP6, to make the voltage on integrated circuit (IC) 1 the 6th pin be upper voltage limit U60=U5.
Corresponding with above-mentioned setting, the corresponding relation of water temperature T and voltage U 2, U6 also becomes:
When water temperature T lower than lower limit temperature Tmin is T<Tmin, voltage U 2<U20=1/2U5 is U2<1/2U5;
When water temperature T higher than ceiling temperature Tmax is T>Tmax, voltage U 6>U60=U5 is U6>U5.
The purpose of doing design like this is: because the value of voltage U 5 is less than the value of supply voltage Uc, therefore, the value of noise signal voltage U n just can reduce, and simultaneously, the enlargement factor of amplifying circuit 20 also can reduce.For example, if the 5th potentiometer RP5 in adjustment Fig. 4, make U5=0.5V, while setting ultimate temperature as stated above, lower voltage limit U20=1/2U5 corresponding to lower limit temperature Tmin need only 0.25V, and the upper voltage limit U60=U5 that ceiling temperature Tmax is corresponding need only 0.5V.
In sum, can reach a conclusion:
When 5 pin that are 1, described integrated circuit (IC) 1 at the first embodiment connect the 7th capacitor C 7, the upper voltage limit U60=2/3Uc that ceiling temperature Tmax is corresponding; If now the corresponding noise signal voltage that makes the normal operation of system is Un=Un7;
When 5 pin that are 2, described integrated circuit (IC) 1 at the second embodiment meet DC voltage U5, the upper voltage limit U60=U5 that ceiling temperature Tmax is corresponding; If now the corresponding noise signal voltage that makes the normal operation of system is Un=Un5;
3, due to U5 can much smaller than Uc be U5<<Uc, so, in other words Un5 also can be much smaller than Un7: noise signal voltage U n changes at great dynamic range, and the present invention still can work.
The dynamic range of the noise signal voltage U n of assurance system normal operation is large, is of the present invention one large advantage.
Like this, the method that the present invention sets ultimate temperature has two kinds:
The first is: when 5 pin of described integrated circuit (IC) 1 connect capacitor C 7, described temperature setting circuit 40 is set up lower voltage limit U20=1/3Uc, sets up upper voltage limit U60=2/3Uc when water temperature is ceiling temperature Tmax when water temperature is lower limit temperature Tmin;
The second is:, when 5 pin of described integrated circuit (IC) 1 meet DC voltage U5, described temperature setting circuit 40 is set up lower voltage limit U20=1/2U5, sets up upper voltage limit U60=U5 when water temperature is ceiling temperature Tmax when water temperature is lower limit temperature Tmin;
After doing above-mentioned design, the integrated circuit (IC) 1 in the present embodiment 2 just has following characteristic:
Its 5 pin has accessed DC voltage U5;
When the voltage U 2<U20 on its 2 pin is U2<1/2U5, the voltage U 3 of its 3 pin output is high level;
When the voltage U 6>U60 on its 6 pin is U6>U5, the voltage U 3 of its 3 pin output is low level.
Two, the connection of the relay J contact in executive circuit 50 is not identical with embodiment 1, embodiment 1 use be moving together contact DH, the present embodiment 2 use be break contact (normally closed contact) DD.
Three, LED reconfiguration to 7 pin, the relay J of integrated circuit (IC) 1 directly is connected with 3 pin of integrated circuit (IC) 1 with the 3rd diode D3 parallel connection later; And, 7 pin of the negative pole termination integrated circuit (IC) 1 of LED, relay J is with after the 3rd diode D3 is in parallel, 3 pin of the negative pole termination integrated circuit (IC) 1 of the 3rd diode D3, positive terminal link ground.
3 pin of integrated circuit (IC) 1, the logical relation of 7 pin are:
When the voltage U 3 of 3 pin outputs is low level, 7 pin are to the circuit ground short circuit;
When the voltage U 3 of 3 pin outputs is high level, 7 pin are opened a way to circuit ground.
Corresponding with above-mentioned change, the control procedure of the present embodiment 2 also correspondingly becomes:
1, cooling: when the water temperature T in container (or pipeline) AV is T>Tmax higher than ceiling temperature Tmax, voltage U 6 on 6 pin of integrated circuit (IC) 1 is U6>U60 higher than upper voltage limit, the voltage U 3 of its 3 pin output is low level, the relay J dead electricity, its break contact DD closure, AC220V is applied to load RL two ends; Simultaneously, 7 pin of integrated circuit (IC) 1 are to the circuit ground short circuit, and LED is lighted, and mean that load RL switches on.
If the refrigeration plant that load RL is water, after load RL energising, water temperature in container AV will progressively descend, when water temperature T lower than smallest limit temperature T min is T<Tmin, voltage U 2 on 2 pin of integrated circuit (IC) 1 is U2<U20 lower than lower voltage limit, and the voltage U 3 of its 3 pin output is high level, and relay J obtains electric, its break contact DD disconnects, and load RL outage stops refrigeration; Simultaneously, 7 pin of integrated circuit (IC) 1 are to circuit ground open circuit, and LED extinguishes, and mean that load RL cuts off the power supply.
2, insulation:
Load RL outage stops refrigeration~system and enters incubation step~water temperature T and again rise to T>Tmax
After, system is carried out " refrigeration cool-down " step again, circulation so again and again, and capable of controlling water temperature T between lower limit temperature Tmin and ceiling temperature Tmax, that is: controls water temperature T in the scope of Tmin<T<Tmax.
The water temperature of the suitable water cooling system as high power broadcast transmitter, radar transmitter, motor car engine, diesel engine of the present embodiment 2 is controlled.
In sum, executive circuit 50 of the present invention water temp. auto-control according to the following steps:
When water temperature T lower than smallest limit temperature T min is T<Tmin, the voltage U 2 on 2 pin of integrated circuit (IC) 1 is U2<U20 lower than lower voltage limit, and the voltage U 3 of its 3 pin output is high level, and relay J obtains electric;
When water temperature T higher than ceiling temperature Tmax is T>Tmax, the voltage U 6 on 6 pin of integrated circuit (IC) 1 is U6>U60 higher than lower voltage limit, and the voltage U 3 of its 3 pin output is low level, the relay J dead electricity.
According to technology provided by the present invention, it will be apparent to those skilled in the art: if by the position reciprocity of relay J, LED, be 3 pin that 7 pin, LED that relay J is connected to integrated circuit (IC) 1 connect integrated circuit (IC) 1, logical relation according between break contact DD, the moving together contact DH of 7 pin of integrated circuit (IC) 1,3 pin, relay J, also can realize the automatic control to water temperature.
The invention discloses the technology of utilizing noise in water immediately to control water temperature, that according to technical thought provided by the present invention, designs is equal to or the technology of equivalent transformation gained, all in the protection domain of the claims in the present invention.