WO2018043735A1 - 静電噴霧装置 - Google Patents
静電噴霧装置 Download PDFInfo
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- WO2018043735A1 WO2018043735A1 PCT/JP2017/031736 JP2017031736W WO2018043735A1 WO 2018043735 A1 WO2018043735 A1 WO 2018043735A1 JP 2017031736 W JP2017031736 W JP 2017031736W WO 2018043735 A1 WO2018043735 A1 WO 2018043735A1
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- spray
- voltage
- electrode
- temperature
- time
- Prior art date
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
- B05B5/053—Arrangements for supplying power, e.g. charging power
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
- B05B12/004—Arrangements for controlling delivery; Arrangements for controlling the spray area comprising sensors for monitoring the delivery, e.g. by displaying the sensed value or generating an alarm
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
- B05B12/08—Arrangements for controlling delivery; Arrangements for controlling the spray area responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means
- B05B12/10—Arrangements for controlling delivery; Arrangements for controlling the spray area responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means responsive to temperature or viscosity of liquid or other fluent material discharged
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
- B05B12/08—Arrangements for controlling delivery; Arrangements for controlling the spray area responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means
- B05B12/12—Arrangements for controlling delivery; Arrangements for controlling the spray area responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means responsive to conditions of ambient medium or target, e.g. humidity, temperature position or movement of the target relative to the spray apparatus
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/007—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means the high voltage supplied to an electrostatic spraying apparatus during spraying operation being periodical or in time, e.g. sinusoidal
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
- B05B5/053—Arrangements for supplying power, e.g. charging power
- B05B5/0533—Electrodes specially adapted therefor; Arrangements of electrodes
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
- B05B5/057—Arrangements for discharging liquids or other fluent material without using a gun or nozzle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/08—Plant for applying liquids or other fluent materials to objects
Definitions
- the present invention relates to an electrostatic spraying device.
- a spraying apparatus that ejects liquid in a container from a nozzle has been applied to a wide range of fields.
- an electrostatic spraying device that atomizes and sprays a liquid by electrohydrodynamics (EHD) is known.
- EHD electrohydrodynamics
- This electrostatic spraying device forms an electric field in the vicinity of the tip of the nozzle, and uses the electric field to atomize and spray the liquid at the tip of the nozzle.
- Patent Document 1 is known as a document disclosing such an electrostatic spraying device.
- the electrostatic spraying device of Patent Document 1 includes a current feedback circuit, and the current feedback circuit measures the current value of the reference electrode. Since the electrostatic spraying device of Patent Document 1 is charge-balanced, the current value is measured and referenced to accurately grasp the current at the spray electrode. And the electrostatic spraying apparatus of patent document 1 is improving the stability of spraying using the feedback control which maintains the electric current value in a spray electrode at a constant value.
- the electrostatic spraying device of Patent Document 1 needs to include a current feedback circuit for performing feedback control, and the number of electronic components mounted on the board increases accordingly. Along with this, the electrostatic spraying device of Patent Document 1 increases the circuit design burden and manufacturing cost. Moreover, in the electrostatic spraying apparatus of patent document 1, when a feedback circuit does not exist, the problem that spraying stability is impaired arises.
- the present invention has been made to solve the above problems, and an object of the present invention is to provide an electrostatic spraying device having a simple structure and excellent spray stability.
- an electrostatic spraying apparatus sprays liquid from the tip of the first electrode by applying a voltage between the first electrode and the second electrode.
- An electrostatic spraying device A voltage applying unit that applies the voltage between the first electrode and the second electrode; Independently of the current value and the voltage value in the first electrode and the second electrode, at least one of (i) the surrounding environment of the device and (ii) the operating state of the power source that supplies power to the device And a control unit that controls the output power of the voltage application unit based on operating environment information indicating the above.
- the conventional feedback control is current feedback control
- the current value of the second electrode is measured, and the feedback control is performed so that the measured value becomes a predetermined current value. I do. Therefore, the conventional feedback control requires a feedback circuit, and the circuit structure (circuit configuration) is complicated. Further, when there is no feedback circuit, the spray stability is impaired.
- the control unit is based on the above operating environment information independently of the current value and the voltage value in the first electrode and the second electrode.
- the output power of the voltage application unit is controlled (hereinafter, this control may be referred to as “output power control”).
- the output power control can form an electric field suitable for electrostatic spraying between the first electrode and the second electrode even when the resistance value of the first electrode is low. Therefore, the electrostatic spraying device according to one embodiment of the present invention maintains the spray amount and spray stability even under high humidity conditions in which leakage current is likely to occur between the first electrode and the second electrode. can do. In addition, the spray amount and spray stability of the electrostatic spray device according to one embodiment of the present invention are comparable to conventional current feedback control and the like even under other conditions.
- the electrostatic spraying apparatus does not need to include a feedback circuit that has been considered to be necessary in the past, and can simplify the circuit structure and greatly reduce the manufacturing cost.
- the electrostatic spraying apparatus can provide an electrostatic spraying apparatus having a simple structure and excellent spray stability.
- the voltage application unit is An oscillator that converts a direct current supplied from the power source into an alternating current; A transformer connected to the oscillator and converting the magnitude of the voltage; A converter circuit that is connected to the transformer and converts an alternating current into a direct current, and the control unit outputs a PWM signal (pulse width modulation signal) with a fixed duty cycle to the oscillator May be output.
- PWM signal pulse width modulation signal
- the control unit outputs the PWM signal in which the duty cycle is set to be constant in order to control the output power of the voltage application unit to be constant. Output to the oscillator.
- the electrostatic spraying apparatus performs output power control through setting of the duty cycle of the PWM signal, it can perform output power control without a complicated circuit structure.
- the control unit may control the output power according to a duty cycle of the PWM signal.
- the electrostatic spraying device can perform output power control by changing the duty cycle of the PWM signal.
- the operating environment information may include information indicating at least one of temperature, humidity, pressure, and viscosity of the liquid around the device as information indicating the surrounding environment.
- the electrostatic spraying apparatus which concerns on 1 aspect of this invention is the information which shows at least one of the temperature around the own apparatus, humidity, a pressure, and the viscosity of the said liquid.
- output power control can be performed.
- the driving environment information includes information indicating the temperature around the device
- the control unit controls the output power according to the duty cycle of the PWM signal, and When the temperature rises, increase the duty cycle of the PWM signal, When the temperature is lowered, the duty cycle of the PWM signal may be lowered.
- the electrostatic spray device increases the duty cycle of the PWM signal and increases the intensity of the electric field formed between the first electrode and the second electrode when the temperature around the device increases. Increase Thereby, the electrostatic spraying apparatus which concerns on 1 aspect of this invention can maintain the stability of spraying, even if it is a case where the temperature around the own apparatus is high.
- the electrostatic spraying device reduces the duty cycle of the PWM signal and enables long-term operation when the temperature around the device is low. That is, the electrostatic spraying device according to one embodiment of the present invention can maintain spray stability in terms of long-term operation even when the temperature around the device is low.
- the electrostatic spraying device can maintain spray stability regardless of the temperature by including the above-described configuration.
- the said control part may determine the spraying interval which makes the time which the own apparatus sprays the said liquid, and the time which stops spraying one cycle based on the following formula
- Sprayperiod (T) Spraying interval (s (seconds)) at a temperature T, where the self-spraying time and the spraying-stopping time are one cycle.
- T Air temperature (° C)
- T 0 Initial set temperature (° C)
- Sprayperiod_compensation_rate Spray time compensation rate (-)
- the electrostatic spraying device increases the spraying interval in which the time for spraying the liquid and the time for stopping spraying is one cycle when the temperature around the device becomes high.
- the electrostatic spraying device has a small spraying interval in which the time for spraying the liquid and the time for stopping spraying is one cycle when the temperature around the device is low. To do.
- the electrostatic spraying device can maintain spraying stability regardless of changes in temperature.
- the control unit determines the spray interval by calculation based on the equation (1), the spray interval can be determined quickly and accurately.
- the said control part may determine the time which turns on the said PWM signal based on the following formula
- PWM_ON_time PWM signal ON time ( ⁇ s) T: Air temperature (° C)
- PWM_compensation rate PWM compensation rate (/ ° C)
- PWM_ON_time T 0 ): PWM signal ON time ( ⁇ s) at the initial set temperature T 0 It is.
- the electrostatic spray device extends the ON time of the PWM signal when the temperature around the device becomes high. Moreover, the electrostatic spraying apparatus which concerns on 1 aspect of this invention shortens ON time of a PWM signal, when the temperature around the own apparatus becomes low.
- the electrostatic spraying device can maintain spraying stability regardless of changes in temperature.
- control unit determines the ON time of the PWM signal by the calculation based on the equation (2), the ON time of the PWM signal can be determined quickly and accurately.
- the control unit When the temperature rises, increase the spray interval with one cycle of the time for the device to spray the liquid and the time to stop spraying, and increase the duty cycle of the PWM signal, When the temperature is lowered, the spray interval in which the time when the device itself sprays the liquid and the time when the spray is stopped is set as one cycle may be reduced, and the duty cycle of the PWM signal may be lowered.
- the electrostatic spray device increases the duty cycle of the PWM signal in consideration of the viscosity characteristics when the temperature around the device is high. As a result, power consumption increases, but by increasing the spray interval, power consumption is suppressed and a balance of power consumption is achieved.
- the electrostatic spraying device reduces the spraying interval when the temperature around the device is low. As a result, the power consumption increases, but by reducing the duty cycle of the PWM signal, the power consumption is suppressed and the power consumption balance is achieved.
- the stability of the spray is maintained by adjusting the duty cycle of the PWM signal or the spray interval according to the temperature around the device itself.
- the electrostatic spraying device realizes a highly stable operation over a long period of time while taking into account the viscosity characteristics of the liquid and achieving a balance of power consumption.
- the operating environment information may include information indicating a magnitude of at least one of a voltage and a current supplied from the power source to the voltage application unit as information indicating an operation state of the power source.
- the electrostatic spray apparatus which concerns on 1 aspect of this invention is the information which shows the magnitude
- the electrostatic spraying device can perform output power control without necessarily using information indicating the surrounding environment of the device as the operating environment information.
- the electrostatic spraying device includes: A conversion circuit for converting the magnitude of the voltage supplied from the power source to the voltage application unit;
- the conversion circuit is provided between the power source and the voltage application unit,
- the control unit may control the output power by giving a command to increase or decrease the conversion ratio of the voltage in the conversion circuit to the conversion circuit.
- the electrostatic spraying device can perform output power control by increasing or decreasing the voltage conversion magnification in the conversion circuit.
- the electrostatic spraying device can also perform output power control by a method other than changing the duty cycle of the PWM signal.
- the electrostatic spraying device is An electrostatic spraying device that sprays liquid from the tip of the first electrode by applying a voltage between the first electrode and the second electrode, A voltage applying unit that applies the voltage between the first electrode and the second electrode; Independently of the current value and the voltage value in the first electrode and the second electrode, at least one of (i) the surrounding environment of the device and (ii) the operating state of the power source that supplies power to the device And a control unit that controls the output power of the voltage application unit based on operating environment information indicating the above.
- the electrostatic spraying device can provide an electrostatic spraying device having excellent spray stability with a simple structure.
- Elapsed days at a temperature of 15 ° C and relative humidity of 35%, a temperature of 25 ° C and relative humidity of 55%, and a temperature of 35 ° C and relative humidity of 75% when the duty cycle is set to 13.3% It is a graph which shows the relationship between a spray amount. It is a figure which shows the setting of the PWM signal used in the above-mentioned FIG. It is a figure which shows an example of the compensation based on a battery voltage. It is a block diagram of the electrostatic spraying apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the relationship between the input voltage of a transformer, and the voltage of a spray electrode in Embodiment 2 of this invention.
- Embodiment 1 the electrostatic spraying apparatus 100 according to the first embodiment will be described with reference to the drawings.
- the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.
- the output power of the high voltage generator (voltage application unit) 22 is controlled by the duty cycle of the PWM signal (Pulse Width Modulation signal) (output power control is performed).
- PWM signal Pulse Width Modulation signal
- the electrostatic spraying device 100 is a device used for spraying aromatic oil, agricultural chemicals, pharmaceuticals, agricultural chemicals, insecticides, air cleaning chemicals, and the like. As shown in FIG. 1, the electrostatic spraying device 100 includes a spray electrode (first electrode) 1, a reference electrode (second electrode) 2, and a power supply device 3.
- FIG. 2 is a view for explaining the external appearance of the electrostatic spraying device 100.
- the electrostatic spraying device 100 has a rectangular shape.
- a spray electrode 1 and a reference electrode 2 are disposed on one surface of the apparatus.
- the spray electrode 1 is located in the vicinity of the reference electrode 2.
- An annular opening 11 is formed so as to surround the spray electrode 1.
- An annular opening 12 is formed so as to surround the reference electrode 2.
- a voltage is applied between the spray electrode 1 and the reference electrode 2, whereby an electric field is formed between the spray electrode 1 and the reference electrode 2.
- a positively charged droplet is sprayed from the spray electrode 1.
- the reference electrode 2 is negatively charged by ionizing air in the vicinity of the electrode.
- the negatively charged air moves away from the reference electrode 2 due to the electric field formed between the electrodes and the repulsive force between the negatively charged air particles. This movement generates a flow of air (hereinafter also referred to as an ion flow), and positively charged droplets are sprayed in a direction away from the electrostatic spraying device 100 by the ion flow.
- the electrostatic spraying device 100 may have other shapes instead of a rectangular shape. Moreover, the opening 11 and the opening 12 may have a shape different from the annular shape, and the opening dimensions thereof may be adjusted as appropriate.
- FIG. 3 is a view for explaining the spray electrode 1 and the reference electrode 2.
- the spray electrode 1 has a conductive conduit such as a metallic capillary (for example, 304 type stainless steel) and a tip 5 that is a tip.
- the spray electrode 1 is electrically connected to the reference electrode 2 via the power supply device 3.
- a spray material (hereinafter referred to as “liquid”) is sprayed from the tip portion 5.
- the spray electrode 1 has an inclined surface 9 that is inclined with respect to the axial center of the spray electrode 1, and the tip is narrower and sharper toward the tip 5.
- the reference electrode 2 is made of a conductive rod such as a metal pin (for example, a 304 type steel pin).
- the spray electrode 1 and the reference electrode 2 are spaced apart from each other at a predetermined interval and are arranged in parallel to each other.
- the spray electrode 1 and the reference electrode 2 are arranged, for example, at an interval of 8 mm from each other.
- the power supply device 3 applies a high voltage between the spray electrode 1 and the reference electrode 2.
- the power supply device 3 applies a high voltage of 1-30 kV (eg, 3-7 kV) between the spray electrode 1 and the reference electrode 2.
- a high voltage is applied, an electric field is formed between the electrodes, and an electric dipole is generated inside the dielectric 10.
- the spray electrode 1 is positively charged and the reference electrode 2 is negatively charged (or vice versa).
- a negative dipole is then generated on the surface of the dielectric 10 closest to the positive spray electrode 1 and a positive dipole is generated on the surface of the dielectric 10 closest to the negative reference electrode 2.
- charged gas and substance species are released by the spray electrode 1 and the reference electrode 2.
- the charge generated in the reference electrode 2 is a charge having a polarity opposite to the polarity of the liquid.
- the liquid charge is balanced by the charge generated at the reference electrode 2. Therefore, the electrostatic spraying device 100 can achieve spray stability based on the principle of charge balance.
- the dielectric 10 is made of a dielectric material such as nylon 6, nylon 11, nylon 12, polypropylene, nylon 66, or a polyacetyl-polytetrafluoroethylene mixture.
- the dielectric 10 supports the spray electrode 1 at the spray electrode mounting portion 6 and supports the reference electrode 2 at the reference electrode mounting portion 7.
- FIG. 1 is a configuration diagram of an electrostatic spraying device 100.
- the power supply device 3 includes a power supply 21, a high voltage generator 22, and a control circuit (control unit) 24.
- the power source 21 supplies power necessary for the operation of the electrostatic spraying device 100.
- the power source 21 may be a well-known power source and includes a main power source or one or more batteries.
- the power source 21 is preferably a low voltage power source or a direct current (DC) power source, and is configured by combining one or more dry batteries, for example. The number of batteries depends on the required voltage level and the power consumption of the power source.
- the power source 21 supplies DC power (in other words, DC current and DC voltage) to the oscillator 221 of the high voltage generator 22.
- the high voltage generator 22 includes an oscillator 221, a transformer 222, and a converter circuit 223.
- the oscillator 221 converts DC power into AC power (in other words, AC current and AC voltage).
- a transformer 222 is connected to the oscillator 221.
- the transformer 222 converts the magnitude of the alternating current voltage (or the magnitude of the alternating current).
- a converter circuit 223 is connected to the transformer 222.
- Converter circuit 223 generates a desired voltage and converts AC power into DC power.
- the converter circuit 223 includes a charge pump and a rectifier circuit.
- a typical converter circuit is a Cockloft-Walton circuit.
- the control circuit 24 outputs a PWM signal set to a constant value to the oscillator 221.
- PWM is a method of controlling current and voltage by changing the time (pulse width) for outputting a pulse signal.
- the pulse signal is an electric signal that repeats ON and OFF, and is represented by, for example, a rectangular wave.
- the pulse width which is the voltage output time, is represented by the horizontal axis of the rectangular wave.
- a timer that operates at a fixed period is used.
- the position at which the pulse signal is turned on is set in this timer to control the pulse width.
- the ratio that is ON in a certain period is called “duty cycle” (also called “duty ratio”).
- the control circuit 24 includes a microprocessor 241 to cope with various applications.
- the microprocessor 241 may be designed such that the duty cycle of the PWM signal can be further adjusted based on other feedback information (operating environment information) 25.
- the feedback information 25 includes environmental conditions (temperature, humidity, and / or atmospheric pressure), liquid amount, arbitrary settings by the user, and the like.
- the information is given as analog information or digital information and is processed by the microprocessor 241.
- the microprocessor 241 can also compensate for increased spray quality and stability by changing either the spray interval, the time to turn on the spray, or the applied voltage based on the input information. It may be designed.
- the power supply device 3 includes a temperature detection element such as a thermistor used for temperature compensation. At this time, the power supply device 3 changes the spray interval according to the change in the temperature detected by the temperature detection element.
- the spray interval is a spray interval in which the time during which the electrostatic spraying apparatus 100 sprays liquid and the time during which spraying is stopped is one cycle.
- the spraying (ON) period is 35 seconds (while the power supply applies a high voltage between the first electrode and the second electrode), and the spraying stop (OFF) period is 145 seconds (while)
- the spray interval can be changed by software built in the microprocessor 241 of the power source.
- the spray interval may be controlled to increase from the set point when the temperature increases and to decrease from the set point when the temperature decreases.
- the increase and decrease of the spray interval preferably follow a predetermined index determined by the characteristics of the liquid to be sprayed.
- the compensation change amount of the spray interval may be limited so that the spray interval changes only between 0-60 ° C. (eg, 10-45 ° C.). For this reason, extreme temperatures recorded by the temperature sensing element are considered erroneous and are not considered, and for high and low temperatures, an acceptable but not optimal spray interval is set.
- the measurement result of the temperature sensor 251, the measurement result of the humidity sensor 252, the measurement result of the pressure sensor 253, and information 254 relating to the contents of the liquid for example, the liquid storage amount is measured with a level meter.
- the information 254 related to the contents of the liquid may include information indicating the viscosity of the liquid (for example, information indicating the result of measuring the viscosity of the liquid with a viscosity sensor (not shown)).
- driving environment information information indicating at least one of (i) the ambient environment of the electrostatic spraying device 100 and (ii) the operating state of the power source 21 that supplies power to the electrostatic spraying device 100 is referred to as driving environment information.
- Feedback information 25 may be used as the driving environment information.
- the operating environment information includes information indicating at least one of the ambient temperature, humidity, pressure, and the viscosity of the liquid around the electrostatic spraying device 100 as information indicating the surrounding environment of the electrostatic spraying device 100. You can leave.
- information indicating the ambient temperature of the electrostatic spraying device 100 temperature information
- the operating environment information includes information indicating the operating state of the power source 21 (eg, measurement result of the voltage / current sensor 255) will be described later.
- the above operating environment information is stored in the internal memory of the control circuit 24, for example.
- the control circuit 24 may include an internal memory such as a flash memory.
- the control circuit 24 executes various output power controls described later with reference to, for example, the operating environment information stored in the internal memory. Normally, the control circuit 24 outputs a PWM signal to the oscillator 221 from the output port of the microprocessor 241.
- the spray duty cycle and spray interval may also be controlled via the same PWM output port. While the electrostatic spraying device 100 sprays liquid, a PWM signal is output to the oscillator 221.
- the control circuit 24 controls the output voltage of the high voltage generator 22 by controlling the amplitude, frequency, or duty cycle of the alternating current in the oscillator 221, and the voltage on-off time (or a combination thereof). It may be possible to control.
- FIG. 4 is a configuration diagram of a typical electrostatic spraying apparatus 200. Hereinafter, only differences from the power supply device 3 of FIG. 1 will be described.
- the electrostatic spraying device 200 uses current feedback control that maintains the current value of the reference electrode 2 at a constant value.
- the electrostatic spraying device 200 includes a power supply device 300, and the power supply device 300 includes a power supply 21, a high voltage generator 22, a control circuit 24, and a monitoring circuit 23.
- the monitoring circuit 23 includes a current feedback circuit 231 and a voltage feedback circuit 232.
- the current feedback circuit 231 measures the current value of the reference electrode 2. Since the electrostatic spraying device 200 is charge-balanced, the current value at the spray electrode 1 can be accurately monitored by measuring and referring to the current value of the reference electrode 2.
- the current feedback circuit 231 may include any conventional current measuring device such as a current transformer.
- control circuit 24 changes the duty cycle of the PWM signal so that the current value of the reference electrode 2 is maintained at a constant value. Then, the control circuit 24 outputs the changed PWM signal to the oscillator 221.
- the monitoring circuit 23 may also include a voltage feedback circuit 232, in which case the voltage applied to the spray electrode is measured.
- the applied voltage is directly monitored by measuring the voltage at the junction of two resistors forming a voltage divider connecting the spray electrode 1 and the reference electrode 2.
- the applied voltage is monitored by measuring the voltage generated at a node in the Cockloft-Walton circuit using similar voltage divider principles.
- the feedback information is processed through an A / D exchanger or by comparing the feedback signal with a reference voltage value using a comparator.
- the typical electrostatic spraying apparatus 200 uses current feedback control that maintains the current value of the reference electrode 2 at a constant value.
- the feedback control may be voltage feedback control or the like, and various feedback controls will be described below. In addition, the problem of each feedback control will be described.
- feedback control examples include current feedback control, voltage feedback control, current / voltage feedback control, and output power feedback control. Hereinafter, each feedback control will be described.
- the current feedback control is a control for keeping the current value of the reference electrode at a constant value, and has an advantage of low power consumption.
- the current feedback control when the resistance value of the spray electrode 1 is lower than a certain value, it is difficult to form an electric field suitable for spraying the liquid between the spray electrode 1 and the reference electrode 2. As such a case, a case where a leakage current occurs between the spray electrode 1 and the reference electrode 2 can be considered. This will be described with reference to FIG.
- FIG. 5 is a graph showing an example of the relationship between the resistance value of the spray electrode 1 and the voltage value of the spray electrode 1 based on current feedback control.
- the resistance value of the spray electrode 1 is 5.5 G ⁇ or more and 8 or more.
- the voltage of the spray electrode 1 is in a voltage range suitable for liquid spraying. That is, when the resistance value of the spray electrode 1 is 5.5 G ⁇ or more and 8.0 G ⁇ or less, an electric field suitable for spraying a liquid is formed between the spray electrode 1 and the reference electrode 2.
- the resistance value of the spray electrode 1 of 5.5 G ⁇ to 8.0 G ⁇ is an allowable range for normal operation.
- the current feedback control has a problem that it is difficult to generate an electric field suitable for spraying when the resistance value of the spray electrode 1 is lower than a certain value.
- the current feedback control requires a current feedback control circuit, and the current feedback control circuit needs to be configured to prevent electrostatic discharge and overvoltage. That is, the current feedback control has a problem that the circuit structure becomes complicated and the manufacturing cost increases.
- the current feedback control is changed to voltage feedback control (described later) in order to form a suitable electric field between the spray electrode 1 and the reference electrode 2. Control of switching can be considered.
- voltage feedback control requires a high output voltage in order to produce good spray results in various operating environments. Therefore, the voltage feedback control has a problem that current consumption increases. Moreover, since voltage feedback control requires a voltage feedback control circuit, there is a problem that the circuit structure becomes complicated and the manufacturing cost increases.
- the output power feedback control is a control method for maintaining the power (output power), which is the product of the current value and the voltage value, at the spray electrode 1 at a constant value.
- the output power feedback control has low power efficiency and has a narrow tolerance range of the resistance value of the spray electrode 1 as compared with the current / voltage feedback control. This is because when the resistance value of the spray electrode 1 falls below a certain value, the output power falls below the level at which electrostatic spraying is performed.
- FIG. 6 is a graph showing the relationship between the resistance value of the spray electrode 1 and the voltage value at the spray electrode 1 for each of current feedback control, voltage feedback control, current / voltage feedback control, and output power feedback control.
- the hatched portion in the figure indicates a region corresponding to the allowable range (5.5 G ⁇ to 8.0 G ⁇ ) of the resistance value of the spray electrode 1 and the voltage range.
- the voltage value of the spray electrode 1 becomes the lowest when current feedback control is used, and the current is considered from the viewpoint of power consumption. Feedback control is optimal. On the other hand, when the voltage feedback control is used, the voltage value of the spray electrode 1 becomes the highest, and the power consumption increases as compared with the current feedback control.
- the current feedback control is optimal.
- the current feedback control has a problem that an electric field suitable for electrostatic spraying is not formed between the spray electrode 1 and the reference electrode 2 when the resistance value of the spray electrode 1 is lower than the allowable range.
- output power control a control method called output power control.
- the control circuit 24 outputs a PWM signal set to a constant value to the oscillator 221 of the high voltage generator 22 based on the above-described operating environment information. To do. Thereby, in the electrostatic spraying apparatus 100, the output power of the high voltage generator 22 (more specifically, the power supplied from the high voltage generator 22 to the spray electrode 1) is constant.
- the control method of the electrostatic spraying apparatus 100 is referred to as output power control.
- the output power control the output power of the high voltage generator 22 is controlled based on the above-described operating environment information, independently of the current value and voltage value at the spray electrode 1 and the reference electrode 2.
- the output power control has a different technical idea from the output power feedback control in which the output power is controlled to be constant by performing feedback control on the product of the current value and the voltage value in the spray electrode 1.
- FIG. 7 is a graph showing the relationship between the resistance value of the spray electrode and the voltage of the spray electrode in the case of output power control and output power feedback control.
- the voltage of the spray electrode 1 at the maximum resistance value (8 G ⁇ in FIG. 6) of the spray electrode 1 by the output power control and the output power feedback control are about 7 kV.
- the output voltage at the spray electrode 1 by the output power control becomes higher than the output voltage by the output power feedback control. This means that, in the range where the resistance value of the spray electrode 1 is lower than 8 G ⁇ , the electrostatic spray performance of the output power control is higher than the electrostatic spray performance of the output power feedback control.
- the output power control does not require a feedback circuit, simplifies the circuit structure, and can greatly reduce the manufacturing cost of the electrostatic spraying device 100.
- FIG. 8 is a graph showing the relationship between the input power from the power source 21 to the high voltage generator 22 and the duty cycle of the PWM signal.
- the setting value of the duty cycle of the PWM signal is changed in several patterns. Then, the current consumption of the battery corresponding to the changed set value is measured. Next, the input power from the power source 21 to the high voltage generator 22 is calculated from (current consumption) ⁇ (battery voltage), and the input power is plotted against the duty cycle of the PWM signal.
- the input power and the duty cycle of the PWM signal are in a proportional relationship. From this, it is understood that the output power of the high voltage generator 22 can be controlled through the setting of the duty cycle of the PWM signal. This is because the output power of the high voltage generator 22 changes according to the above-described input power. From the viewpoint of controlling the input power to the high voltage generator 22, the output power control of the present embodiment may be referred to as input power control.
- FIG. 9 is a diagram showing the relationship between the elapsed days and the spray amount for each of the current feedback control and the output power control.
- the actual duty cycle is determined by observing the state of spraying.
- the duty cycle is set to 6.7%.
- the PWM cycle is 1.2 ms, and the ON time is 80 ⁇ s.
- both the current feedback control and the output power control change while maintaining a spray amount of about 0.6 g / day regardless of the number of days elapsed.
- 2 ⁇ which is twice the standard deviation ( ⁇ )
- ⁇ changes around 10% regardless of the number of days elapsed. That is, there is no significant difference between the current feedback control and the output power control in the spray amount and its stability.
- FIG. 10 is a diagram showing the relationship between elapsed days and battery voltage for each of current feedback control and output power control.
- the battery voltage for current feedback control is higher than the battery voltage for output power control. From this, it can be seen that the power consumption of the output power control is higher. However, it should be noted that even in the output power control, the spray performance falls within an allowable range when used for one month using two AA batteries.
- FIGS. 11, 13, and 15 are graphs of the average value when sprayed 10 times and the double value of the standard deviation ( ⁇ ), respectively.
- FIG. 11 is a diagram showing the relationship between the number of days elapsed and the spray amount at an air temperature of 15 ° C. and a relative humidity of 35%.
- FIG. 12 is a diagram showing the relationship between the number of spray days and the output power at an air temperature of 15 ° C. and a relative humidity of 35%.
- FIG. 13 is a diagram showing the relationship between the number of days elapsed and the spray amount at an air temperature of 25 ° C. and a relative humidity of 35%.
- FIG. 14 is a diagram showing the relationship between the number of spray days and the output power at an air temperature of 25 ° C. and a relative humidity of 35%.
- FIG. 15 is a diagram showing the relationship between the number of days elapsed and the spray amount when the temperature is 35 ° C. and the relative humidity is 75%.
- FIG. 16 is a diagram showing the relationship between the number of spray days and the output power at an air temperature of 35 ° C. and a relative humidity of 75%.
- the average spray amount is maintained at 0.6 g / day or more under any condition. From this, it can be seen that the output power control can spray a desired amount of liquid under various conditions. Note that the double value of the standard deviation ( ⁇ ) became more unstable and unstable as the temperature and humidity increased.
- the output power is maintained at around 5.0 mW and the spray electrode 1 has a sufficiently high voltage value under any condition.
- FIG. 17 shows an air temperature of 15 ° C./relative humidity of 35%, an air temperature of 25 ° C./relative humidity of 55%, an air temperature of 35 ° C. ⁇ when the duty cycle is changed to 6.7%, 13.3%, 3.3%. It is a graph which shows the relationship between the elapsed days and the spray amount in relative humidity 75%.
- the output power is acquired as the product of the output voltage and the current value at the spray electrode 1.
- the output power is the sum of the power consumed by electrostatic spraying, specifically, the power required to positively charge a droplet and the power required to generate a negatively charged ion stream. It is the total value.
- the output power is high under high humidity. This is considered to be due to the electric charge charged on the dielectric around the spray electrode 1. In order to improve the spray characteristics under high humidity, it is preferable to increase the output power. This is because the electric field around the spray electrode 1 is strengthened to generate a sufficient ion flow.
- the spray characteristics under the high humidity of 35 ° C and 75% relative humidity change the most complicated. As this factor, the influence by the electric charge charged in the dielectric around the spray electrode 1 can be considered.
- the spray characteristics at an air temperature of 15 ° C. and a relative humidity of 35% and an air temperature of 25 ° C. and a relative humidity of 55% are stable without changing so much.
- the duty cycle was set to 6.7% (PWM period 1.2 ms, ON time 80 ⁇ s). Subsequently, the duty cycle was set to 13.3% from the 6th day to the 16th day (PWM period 1.2 ms, ON time 160 ⁇ s). Further, the duty cycle was set to 3.3% after the 16th day from the start of the test (PWM period 1.2 ms, ON time 40 ⁇ s).
- the spray stability is the best when the duty cycle is set to 13.3%. This is considered to be because the influence of the electric charge charged on the dielectric around the spray electrode 1 is the smallest. On the other hand, when the duty cycle is set to 3.3%, the spray stability is lowest. This is because the influence of the electric charges charged on the dielectric around the spray electrode 1 is the largest, and the spray characteristics under a high humidity of 35 ° C. and 75% relative humidity are significantly affected.
- a desired spray amount can be stably obtained by output power control without using feedback control.
- the duty cycle to be high and reducing the influence of the electric charge charged on the dielectric around the spray electrode 1, it is possible to further improve the spray stability even under high humidity conditions.
- FIG. 17 shows that the spray fluctuation is suppressed by increasing the set value of the duty cycle of the PWM signal.
- FIG. 18 shows the number of days elapsed and the spray amount at a temperature of 15 ° C./relative humidity of 35%, a temperature of 25 ° C./relative humidity of 55%, and a temperature of 35 ° C./relative humidity of 75% when the duty cycle is set to 13.3% It is a graph which shows the relationship.
- the spray state under high humidity of 35 ° C. and 75% relative humidity is stabilized. Further, when the duty cycle is set to 13.3%, the spray characteristics are stable under the humidity conditions of an air temperature of 15 ° C. and a relative humidity of 35% and an air temperature of 25 ° C. and a relative humidity of 55%.
- FIG. 18 shows that when an electrostatic spraying apparatus is operated using two AA batteries, the temperature is 15 ° C. and a relative humidity of 35% is less than 15 days, and the temperature is 25 ° C. and the relative humidity is 55%. Indicates that the number of days of operation is less than a day. Since the amount of power stored in the battery in advance is finite, if the operating days are short, the user is required to replace the battery excessively.
- This compensation scheme has been studied focusing on the fact that it is preferable to increase the duty cycle of the PWM signal under high humidity conditions, and that the humidity increases as the temperature increases.
- control circuit 24 has the following equation (1), that is,
- Sprayperiod (T) Spraying time (s) in which the electrostatic spraying apparatus 100 sprays the liquid at the temperature T and stops spraying as one cycle.
- T Air temperature (° C)
- T 0 Initial set temperature (° C)
- Sprayperiod_compensation_rate Spray time compensation rate (-)
- Sprayperiod (T 0 ) Spray time (s) in which the electrostatic spraying apparatus 100 sprays the liquid and stops spraying at the initial set temperature T 0 as one cycle.
- the spraying time (spraying interval) Sprayperiod (T) may be determined based on the above.
- control circuit 24 has the following equation (2):
- the PWM signal ON time (time for turning on the PWM signal) PWM_ON_time (T) may be determined based on the above.
- the above formulas (1) and (2) are formulas showing a compensation scheme, and are used when the temperature T is 10 ° C. or higher and 40 ° C. or lower. Note that, in FIG. 17 and the like, the case where the temperature T is 15 ° C. or more and 35 ° C. or less is illustrated, but the inventor of the present application indicates that the temperature T is (i) 10 ° C. or more and 15 ° C. or less, and ( ii) It was confirmed that the above formulas (1) and (2) were applicable even when the temperature was 35 ° C. or higher and 40 ° C. or lower.
- the temperature T may be acquired by the temperature sensor 251 illustrated in FIG. 1 or may be acquired from an external thermometer. As described above, the operating environment information includes temperature information (information indicating the temperature T).
- the temperature information is transmitted to the microprocessor 241 from the temperature sensor 251 or an external thermometer.
- the microprocessor 241 inserts the temperature information into the equations (1) and (2), and calculates Sprayperiod (T) and PWM_ON_time (T).
- Initial setting temperature T 0 (° C.), spray time compensation rate ( ⁇ ), spray period (T 0 ) in equation ( 1 ), and PWM_compensation rate: / ° C., PWM_compensation rate: / ° C. in equation (2) 241 may be input in advance. Each value may be stored in an internal memory of the control circuit 24 or the like.
- T 0 15 ° C.
- Sprayperiod_compensation_rate 3.311 / ° C.
- the spray period (T 0 ) is 171.6 (s) at 15 ° C.
- PWM_compensation rate 5 / ° C.
- PWM_ON_time (T 0 ) 80 ( ⁇ s) at 15 ° C.
- the compensation scheme shown in equations (1) and (2) sets the duty cycle setting value of the PWM signal as the temperature changes. That is, when the temperature rises, the setting value of the duty cycle of the PWM signal is raised, and when the temperature falls, the setting value of the duty cycle of the PWM signal is lowered.
- the PWM signal set to a constant value is sent to the oscillator 221 of the high voltage generator 22.
- the stability of the spray can be maintained by using the output power control that is output.
- the electrostatic spraying apparatus 100 performs output power control for each temperature using the set value of the duty cycle of the PWM signal corresponding to the temperature.
- FIG. 19 shows a temperature 15 ° C./relative humidity 35%, a temperature 25 ° C./relative humidity 55%, a temperature 35 ° C./relative humidity 75 when the duty cycle is set to 13.3% and the compensation scheme is applied. It is a graph which shows the relationship between the elapsed days in% and the spray amount.
- the electrostatic spraying apparatus 100 may be combined with the following compensation scheme in consideration of the viscosity characteristics of the liquid. Specifically, the viscosity of the liquid increases when the temperature decreases, and decreases when the temperature increases. Therefore, when the temperature rises, for example, the control circuit 24 lowers the set value of Sprayperiod (T). Thereby, when the temperature becomes high, the power consumption of the battery is suppressed. On the other hand, when the temperature rises, for example, the control circuit 24 increases PWM_ON_time. This increases battery power consumption as the temperature rises. Compensating schemes that achieve optimal power consumption over a wide range of temperatures, while balancing the two. In addition, this scheme moderately suppresses the amount of liquid sprayed under high temperature conditions.
- T Sprayperiod
- output power control is further performed by using information other than temperature information (eg, information indicating humidity, pressure, and viscosity) included in information indicating the ambient environment of the electrostatic spraying apparatus 100 (an aspect of the operating environment information). Can also be done. Alternatively, output power control may be performed using only information other than temperature information.
- information other than temperature information eg, information indicating humidity, pressure, and viscosity
- output power control may be performed using only information other than temperature information.
- FIG. 20 is a diagram illustrating the setting of the PWM signal used in FIG. 19 described above.
- the horizontal axis indicates the air temperature (temperature) T.
- the vertical axis at the left end indicates PWM_ON_time (T), and the vertical axis at the right end indicates the duty cycle (PWM duty) of the PWM signal.
- T 0 15 ° C.
- PWM_compensation rate 5 / ° C.
- the shape of the liquid sprayed from the tip 5 of the spray electrode 1 at each temperature of T 15 ° C., 25 ° C., and 35 ° C. was confirmed. That is, a good spray state and stable spray amount were confirmed in the temperature range of 15 ° C. to 35 ° C.
- Example of compensation based on battery voltage the compensation method in the case where the driving environment information includes information indicating the temperature T (specific example of information indicating the surrounding environment of the electrostatic spraying apparatus 100) has been described. Subsequently, a compensation method in the case where the operating environment information includes information indicating the operating state of the power source 21 (example: measurement result of the voltage / current sensor 255) will be exemplified.
- the operating environment information may include information indicating at least one of the voltage and current supplied from the power source 21 to the high voltage generator 22 as information indicating the operating state of the power source 21.
- the driving environment information is information indicating the magnitude of the voltage (battery voltage) supplied from the power source 21 to the high voltage generator 22 will be exemplified.
- the battery voltage may be measured by the voltage / current sensor 255.
- FIG. 21 is a diagram illustrating an example of compensation based on the battery voltage.
- the horizontal axis represents the battery voltage.
- the vertical axis at the left end indicates the voltage of the spray electrode 1, and the vertical axis at the right end indicates the duty cycle (PWM duty) of the PWM signal. It is assumed that the initial value of the battery voltage is 3.2V.
- the battery voltage gradually decreases with time. Therefore, as shown in the legend “no PWM compensation” in FIG. 21, unless the duty cycle of the PWM signal is adjusted, the voltage of the spray electrode 1 also decreases as the battery voltage decreases. For this reason, when battery voltage becomes low to some extent, the stability of spraying may be impaired.
- the control circuit 24 adjusts the duty cycle so as to increase the duty cycle of the PWM signal. Therefore, even if a battery voltage falls with progress of time, since the voltage of the spray electrode 1 can be kept constant (about 6 kV), the stability of spraying can be maintained.
- the control circuit 24 is independent of the current value and the voltage value in the spray electrode 1 and the reference electrode 2 (i) The output power of the high voltage generator 22 is controlled based on the operating environment information indicating at least one of the environment and (ii) the operating state of the power source 21. Thereby, it becomes possible to implement
- Embodiment 2 of the present invention will be described with reference to FIGS. 22 and 23.
- FIG. 22 is a configuration diagram of the electrostatic spraying apparatus 100a of the present embodiment. In the following, only differences from the electrostatic spray device 100 of FIG. 1 will be described.
- the electrostatic spraying apparatus 100 a includes (i) a conversion circuit 26, and (ii) the static signal of the first embodiment is not output from the control circuit 24 to the oscillator 221. Different from electrospraying device. As described below, the electrostatic spraying device 100a is configured for the purpose of performing output power control by a method other than PWM.
- the conversion circuit 26 is a circuit that converts the magnitude of the voltage supplied from the power source 21 to the high voltage generator 22.
- the conversion circuit 26 is a DC / DC converter, for example.
- the conversion circuit 26 is provided between the power source 21 and the high voltage generator 22.
- the conversion circuit 26 converts the DC voltage V1 (battery voltage as an input voltage) input from the power supply 21 into a DC voltage V2 (output voltage) having a different magnitude. Then, the conversion circuit 26 supplies the voltage V2 to the high voltage generator 22 (more specifically, the oscillator 221).
- K V2 / V1 is referred to as a voltage conversion magnification in the conversion circuit 26.
- FIG. 23 is a diagram showing the relationship between the input voltage of the transformer 222 (in other words, the output voltage of the oscillator 221) and the voltage of the spray electrode 1.
- the horizontal axis represents the input voltage of the transformer 222
- the vertical axis represents the voltage of the spray electrode 1.
- FIG. 23 shows the difference between the input voltage of the transformer 222 and the voltage of the spray electrode 1 when the resistance value of the spray electrode 1 is “4 G ⁇ ”, “5 G ⁇ ”, and “6 G ⁇ ”. The relationship is shown.
- the voltage of the spray electrode 1 can be maintained at a substantially constant value (for example, 6 kV) by appropriately adjusting the input voltage of the transformer 222.
- the output power control described above can be performed by changing the input voltage of the transformer 222 without changing the duty cycle of the PWM signal.
- the control circuit 24 in the present embodiment is configured to give a command to change (increase or decrease) the conversion magnification K described above to the conversion circuit 26.
- the oscillator 221 converts the direct-current voltage (the above-described voltage V ⁇ b> 2) input to itself into an alternating voltage, and supplies the converted alternating voltage to the transformer 222. For this reason, the input voltage of the transformer 222 can be changed by changing the value of the voltage V2.
- V2 K ⁇ V1
- the input voltage of the transformer 222 can be changed.
- the voltage of the spray electrode 1 is determined according to the input voltage of the transformer 222.
- the output power control can be performed by changing the conversion magnification K by the control circuit 24.
- the change of the conversion magnification K by the control circuit 24 is based on the above operating environment information independently of the current value and the voltage value at the spray electrode 1 and the reference electrode 2 as in the output power control of the first embodiment. Done.
- the change of the conversion magnification K in the control circuit 24 may be performed based on the magnitude of the battery voltage (an example of information indicating the operating state of the power supply 21). Further, the conversion magnification K may be changed based on the above-described temperature T (an example of information indicating the surrounding environment of the electrostatic spraying apparatus 100a). Moreover, the conversion magnification K may be changed based on both the magnitude of the battery voltage and the temperature T. As described above, the conversion magnification K may be changed by further using information indicating humidity, pressure, liquid viscosity, and the like.
- the electrostatic spraying device 100a of the present embodiment can perform output power control by changing the conversion magnification K described above. That is, the electrostatic spraying device 100a can perform output power control by a method other than changing the duty cycle of the PWM signal. Also with the electrostatic spraying device 100a, as in the first embodiment, it is possible to realize an electrostatic spraying device excellent in spray stability with a simple structure.
- the present invention relates to an electrostatic spraying device.
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Abstract
Description
上記第1電極と上記第2電極との間に上記電圧を印加する電圧印加部と、
上記第1電極および上記第2電極における電流値および電圧値からは独立して、(i)自装置の周囲環境、および、(ii)自装置に電力を供給する電源の動作状態、の少なくともいずれかを示す運転環境情報に基づいて、上記電圧印加部の出力電力を制御する制御部と、を備えている。
上記電圧印加部は、
上記電源から供給される直流電流を交流電流に変換する発振器と、
上記発振器に接続され、電圧の大きさを変換する変圧器と、
上記変圧器に接続され、交流電流を直流電流に変換するコンバータ回路と、を備え、 上記制御部は、デューティーサイクルを一定に設定したPWM信号(パルス幅変調(Pulse Width Modulation)信号)を上記発振器に出力してもよい。
上記制御部は、PWM信号のデューティーサイクルにより上記出力電力を制御してもよい。
上記運転環境情報は、上記周囲環境を示す情報として、自装置周囲の気温、湿度、圧力、および上記液体の粘度の少なくとも1つを示す情報を含んでいてもよい。
上記運転環境情報は、自装置周囲の気温を示す情報を含んでおり、
上記制御部は、PWM信号のデューティーサイクルにより上記出力電力を制御し、かつ、
上記気温が高くなると、上記PWM信号のデューティーサイクルを上げ、
上記気温が低くなると、上記PWM信号のデューティーサイクルを下げてもよい。
上記制御部は、以下の式(1)に基づいて、自装置が上記液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔を決定してもよい。
Sprayperiod(T):温度Tにおける、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔(s(秒))
T:気温(℃)
T0:初期設定温度(℃)
Sprayperiod_compensation_rate:噴霧時間補償率(-)
Sprayperiod(T0):初期設定温度T0における、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔(s)
である。
上記制御部は、以下の式(2)に基づいて、上記PWM信号をONとする時間を決定してもよい。
PWM_ON_time(T):PWM信号のON時間(μs)
T:気温(℃)
PWM_compensation rate:PWM補償率(/℃)
PWM_ON_time(T0):初期設定温度T0におけるPWM信号のON時間(μs)
である。
上記制御部は、
上記気温が高くなると、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔を大きくし、かつ、上記PWM信号のデューティーサイクルを上げ、
上記気温が低くなると、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔を小さくし、かつ、上記PWM信号のデューティーサイクルを下げてもよい。
上記運転環境情報は、上記電源の動作状態を示す情報として、上記電源から上記電圧印加部に供給される電圧および電流の少なくとも一方の大きさを示す情報を含んでいてもよい。
上記電源から上記電圧印加部に供給される電圧の大きさを変換する変換回路をさらに備えており、
上記変換回路は、上記電源と上記電圧印加部との間に設けられており、
上記制御部は、上記変換回路における上記電圧の変換倍率を増減させる指令を当該変換回路に与えることにより、上記出力電力を制御してもよい。
第1電極と第2電極との間に電圧を印加することにより、当該第1電極の先端から液体を噴霧する静電噴霧装置であって、
上記第1電極と上記第2電極との間に上記電圧を印加する電圧印加部と、
上記第1電極および上記第2電極における電流値および電圧値からは独立して、(i)自装置の周囲環境、および、(ii)自装置に電力を供給する電源の動作状態、の少なくともいずれかを示す運転環境情報に基づいて、上記電圧印加部の出力電力を制御する制御部と、を備えている。
以下、図面を参照しつつ、実施形態1に係る静電噴霧装置100について説明する。以下の説明では、同一の部品および構成要素には同一の符号を付している。それらの名称および機能も同じである。したがって、それらについての詳細な説明は繰り返さない。
静電噴霧装置100は、芳香油、農産物用化学物質、医薬品、農薬、殺虫剤、空気清浄化薬剤等の噴霧等に用いられる装置である。静電噴霧装置100は、図1に示すように、スプレー電極(第1電極)1と、基準電極(第2電極)2と、電源装置3とを備える。
スプレー電極1、および基準電極2を図3により説明する。図3は、スプレー電極1、および基準電極2を説明するための図である。
電源装置3を図1により説明する。図1は、静電噴霧装置100の構成図である。
次に、従来の静電噴霧装置で利用されるフィードバック制御、およびその課題を説明する。そのうえで、当該課題を解決するための本実施の形態に係る静電噴霧装置100について説明する。
従来のフィードバック制御を用いる典型的な静電噴霧装置200及び電源装置300を図4により説明する。図4は、典型的な静電噴霧装置200の構成図である。なお、以下では、図1の電源装置3との相違点のみを説明する。
フィードバック制御には、電流フィードバック制御、電圧フィードバック制御、電流/電圧フィードバック制御、出力電力フィードバック制御などがある。以下、それぞれのフィードバック制御について説明する。
図1に示すように、静電噴霧装置100では、制御回路24が、上述の運転環境情報に基づいて、一定の値に設定されたPWM信号を高電圧発生装置22の発振器221に対して出力する。これにより、静電噴霧装置100では、高電圧発生装置22の出力電力(より具体的には、高電圧発生装置22からスプレー電極1に供給される電力)が一定になる。
次に、異なる条件下での最適なデューティーサイクルについて図17を用いて説明する。図17は、デューティーサイクルを6.7%、13.3%、3.3%と変化させたときの、気温15℃・相対湿度35%、気温25℃・相対湿度55%、気温35℃・相対湿度75%における経過日数と噴霧量との関係を示すグラフである。
図17では、PWM信号のデューティーサイクルの設定値を高くすることで噴霧変動が抑制されることを示した。
T:気温(℃)
T0:初期設定温度(℃)
Sprayperiod_compensation_rate:噴霧時間補償率(-)
Sprayperiod(T0):初期設定温度T0における、静電噴霧装置100が液体を噴霧する時間と噴霧を停止する時間とを一サイクルとする噴霧時間(s)
に基づいて、噴霧時間(噴霧間隔)Sprayperiod(T)を決定してもよい。
PWM_compensation rate:PWM補償率(/℃)
PWM_ON_time(T0):初期設定温度T0におけるPWM信号のON時間(μs)
る時間と噴霧を停止する時間とを一サイクルとする噴霧時間(s)
に基づいて、PWM信号のON時間(PWM信号をONとする時間)PWM_ON_time(T)を決定してもよい。
上述の例では、運転環境情報が気温Tを示す情報(静電噴霧装置100の周囲環境を示す情報の具体例)を含んでいる場合の補償方法について述べた。続いて、運転環境情報が電源21の動作状態を示す情報(例:電圧・電流センサ255の測定結果)を含んでいる場合の補償方法を例示する。
以上のように、本実施形態の静電噴霧装置100において、制御回路24は、スプレー電極1および基準電極2における電流値および電圧値からは独立して、(i)静電噴霧装置100の周囲環境、および、(ii)電源21の動作状態、の少なくともいずれかを示す運転環境情報に基づいて、高電圧発生装置22の出力電力を制御する。これにより、簡易な構造により噴霧安定性に優れた静電噴霧装置を実現することが可能となる。
以下、本発明の実施形態2について、図22および図23に基づいて説明する。
本発明は上述した実施形態に限定されるものではなく、請求項に示した範囲で種々の変更が可能である。すなわち、請求項に示した範囲で適宜変更した技術的手段を組み合わせて得られる実施形態についても本発明の技術的範囲に含まれる。
2 基準電極(第2電極)
3 電源装置
5 先端部
6 スプレー電極取付部
7 基準電極取付部
9 傾斜面
10 誘電体
11、12 開口
21 電源
22 高電圧発生装置(電圧印加部)
24 制御回路(制御部)
25 フィードバック情報(運転環境情報)
26 変換回路
100、100a 静電噴霧装置
221 発振器
222 変圧器
223 コンバータ回路
231 電流フィードバック回路
232 電圧フィードバック回路
241 マイクロプロセッサ
251 温度センサ
252 湿度センサ
253 圧力センサ
254 液体の内容物に関する情報
255 電圧・電流センサ
262 基準電極
Claims (10)
- 第1電極と第2電極との間に電圧を印加することにより、当該第1電極の先端から液体を噴霧する静電噴霧装置であって、
上記第1電極と上記第2電極との間に上記電圧を印加する電圧印加部と、
上記第1電極および上記第2電極における電流値および電圧値からは独立して、(i)自装置の周囲環境、および、(ii)自装置に電力を供給する電源の動作状態、の少なくともいずれかを示す運転環境情報に基づいて、上記電圧印加部の出力電力を制御する制御部と、を備えていることを特徴とする静電噴霧装置。 - 上記電圧印加部は、
上記電源から供給される直流電流を交流電流に変換する発振器と、
上記発振器に接続され、電圧の大きさを変換する変圧器と、
上記変圧器に接続され、交流電流を直流電流に変換するコンバータ回路と、を備え、 上記制御部は、デューティーサイクルを一定に設定したPWM信号(パルス幅変調(Pulse Width Modulation)信号)を上記発振器に出力することを特徴とする請求項1に記載の静電噴霧装置。 - 上記制御部は、PWM信号(パルス幅変調(Pulse Width Modulation)信号)のデューティーサイクルにより上記出力電力を制御することを特徴とする請求項1に記載の静電噴霧装置。
- 上記運転環境情報は、上記周囲環境を示す情報として、自装置周囲の気温、湿度、圧力、および上記液体の粘度の少なくとも1つを示す情報を含んでいることを特徴とする請求項1から3のいずれか1項に記載の静電噴霧装置。
- 上記運転環境情報は、自装置周囲の気温を示す情報を含んでおり、
上記制御部は、PWM信号のデューティーサイクルにより上記出力電力を制御し、かつ、
上記気温が高くなると、上記PWM信号のデューティーサイクルを上げ、
上記気温が低くなると、上記PWM信号のデューティーサイクルを下げることを特徴とする請求項4に記載の静電噴霧装置。 - 上記制御部は、
上記気温が高くなると、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔を大きくし、かつ、上記PWM信号のデューティーサイクルを上げ、
上記気温が低くなると、自装置が液体を噴霧する時間および噴霧を停止する時間を一サイクルとする噴霧間隔を小さくし、かつ、上記PWM信号のデューティーサイクルを下げることを特徴とする請求項5に記載の静電噴霧装置。 - 上記運転環境情報は、上記電源の動作状態を示す情報として、上記電源から上記電圧印加部に供給される電圧および電流の少なくとも一方の大きさを示す情報を含んでいることを特徴とする請求項1から4のいずれか1項に記載の静電噴霧装置。
- 上記電源から上記電圧印加部に供給される電圧の大きさを変換する変換回路をさらに備えており、
上記変換回路は、上記電源と上記電圧印加部との間に設けられており、
上記制御部は、上記変換回路における上記電圧の変換倍率を増減させる指令を当該変換回路に与えることにより、上記出力電力を制御することを特徴とする請求項1に記載の静電噴霧装置。
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JP2018537582A JP6994463B2 (ja) | 2016-09-05 | 2017-09-04 | 静電噴霧装置 |
US16/330,159 US10994292B2 (en) | 2016-09-05 | 2017-09-04 | Electrostatic spraying device |
EP17846738.7A EP3508277A4 (en) | 2016-09-05 | 2017-09-04 | ELECTROSTATIC SPRAYING DEVICE |
BR112019003627-0A BR112019003627B1 (pt) | 2016-09-05 | 2017-09-04 | Dispositivo de pulverização eletrostática |
MX2019002361A MX2019002361A (es) | 2016-09-05 | 2017-09-04 | Dispositivo de pulverizacion electrostatica. |
CN201780053831.7A CN109641223B (zh) | 2016-09-05 | 2017-09-04 | 静电喷雾装置 |
AU2017319627A AU2017319627B2 (en) | 2016-09-05 | 2017-09-04 | Electrostatic spraying device |
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013018477A1 (en) | 2011-07-29 | 2013-02-07 | Sumitomo Chemical Company, Limited | Electrostatic atomizer, and method for electrostatically atomizing by use of the same |
WO2014112447A1 (ja) * | 2013-01-15 | 2014-07-24 | 住友化学株式会社 | 静電噴霧装置、および静電噴霧装置の制御方法 |
JP2014168739A (ja) * | 2013-03-01 | 2014-09-18 | Sumitomo Chemical Co Ltd | 静電噴霧装置、および静電噴霧装置における電流制御方法 |
JP2014233667A (ja) * | 2013-05-31 | 2014-12-15 | 住友化学株式会社 | 静電噴霧装置、および静電噴霧装置の制御方法 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IE45426B1 (en) * | 1976-07-15 | 1982-08-25 | Ici Ltd | Atomisation of liquids |
GB0115355D0 (en) * | 2001-06-22 | 2001-08-15 | Pirrie Alastair | Vaporization system |
JP4665839B2 (ja) | 2006-06-08 | 2011-04-06 | パナソニック電工株式会社 | 静電霧化装置 |
CN101245531B (zh) * | 2006-10-06 | 2012-11-28 | 格罗兹-贝克特公司 | 用于纺织物加工的喷嘴条 |
JP2011073617A (ja) * | 2009-09-30 | 2011-04-14 | Panasonic Electric Works Co Ltd | 車両用の静電霧化装置 |
US8861228B2 (en) * | 2009-12-07 | 2014-10-14 | Durr Systems Gmbh | High voltage controller with improved monitoring and diagnostics |
JP2011173085A (ja) * | 2010-02-25 | 2011-09-08 | Hitachi High-Technologies Corp | Esd装置及びesd方法 |
CN202129158U (zh) * | 2011-06-09 | 2012-02-01 | 邱士峰 | 置地式洒水器 |
JP5968716B2 (ja) | 2012-08-01 | 2016-08-10 | 住友化学株式会社 | 静電噴霧装置 |
JP6199047B2 (ja) * | 2013-02-28 | 2017-09-20 | Hoya株式会社 | 磁気ディスク用ガラス基板の製造方法 |
CN104192310A (zh) * | 2014-09-02 | 2014-12-10 | 太仓市金港植保器械科技有限公司 | 一种静电喷雾装置及航空静电喷雾装置和静电喷雾方法 |
-
2017
- 2017-08-31 TW TW106129692A patent/TW201815478A/zh unknown
- 2017-09-04 JP JP2018537582A patent/JP6994463B2/ja active Active
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Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013018477A1 (en) | 2011-07-29 | 2013-02-07 | Sumitomo Chemical Company, Limited | Electrostatic atomizer, and method for electrostatically atomizing by use of the same |
JP2013027832A (ja) * | 2011-07-29 | 2013-02-07 | Sumitomo Chemical Co Ltd | 静電噴霧装置、および当該静電噴霧装置を用いて静電噴霧を行う方法 |
WO2014112447A1 (ja) * | 2013-01-15 | 2014-07-24 | 住友化学株式会社 | 静電噴霧装置、および静電噴霧装置の制御方法 |
JP2014168739A (ja) * | 2013-03-01 | 2014-09-18 | Sumitomo Chemical Co Ltd | 静電噴霧装置、および静電噴霧装置における電流制御方法 |
JP2014233667A (ja) * | 2013-05-31 | 2014-12-15 | 住友化学株式会社 | 静電噴霧装置、および静電噴霧装置の制御方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP3508277A4 |
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