JP2009052482A - Air compressor and method of controlling driving of motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control the driving of a motor means according to the loading condition of the motor means. <P>SOLUTION: This air compressor 1 comprises a compressed air generating means 3 for generating compressed air, a tank part 2 for reserving the compressed air generated by the compressed air generating means 3, the motor means 4 for driving the compressed air generating means 3, and a control means 5 for controlling the driving quantity of the motor means 4. A pressure detection means 12 for detecting the pressure state of the compressed air reserved in the tank part 2 is installed in the tank part 2. The control means 5 adjust the driving quantity of the motor means 4 according to the pressure state detected by the pressure detection means 12. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an air compressor and a motor drive control method, and more particularly to an air compressor and a motor drive control method for motor means that can drive motor means to supply compressed air to a building drive tool. .

When a driving tool such as a nailing machine using compressed air is used at a construction site, it is necessary to install an air compressor that supplies compressed air to the driving tool. An air compressor generally includes a tank unit that stores compressed air, a compressed air generating unit that generates compressed air, a motor (driving unit) that drives the compressed air generating unit, and a control circuit unit that controls driving of the motor. Has been. (For example, refer to Patent Document 1).
JP 2004-316504 A (refer to page 4 to page 5 and FIG. 1)

  When generating compressed air, the motor is driven to generate compressed air at the compressed air generator and store it in the tank. The motor is driven by the pressure state of the compressed air stored in the tank. For example, the load changes, and the torque generated by driving changes greatly. For example, there is a several-fold difference in the starting torque at the time of starting the motor between the state where the compressed air is not stored in the tank part and the state where the compressed air is kept at a constant pressure (for example, 4 MPa (Pascal)).

  In this way, when the drive load such as the starting torque of the motor greatly changes depending on the pressure state of the compressed air stored in the tank portion, the motor speed is controlled while maintaining a constant drive state (duty). When the pressure of the compressed air in the tank is low (for example, when the air compressor is started), the motor driving load is light and the motor rotation speed increases too much, resulting in an overshoot phenomenon. On the other hand, when the motor drive load is heavy, such as when the pressure of compressed air in the tank is above a certain level, it may take time for the motor speed to reach the desired speed. It was.

  Even when the driving state of the air compressor is stable, even when the operation mode is switched from the normal mode (for example, the reference rotation speed is 3300 rpm) to the silent mode (for example, the reference rotation speed is 1800 rpm), etc. A similar phenomenon may occur due to a change in load state accompanying switching.

  Furthermore, the load change caused by the air compressor may change not only due to the pressure state of the tank section but also due to, for example, the heat generation state of the motor. In such a case, the above-described phenomenon may occur. It was.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide an air compressor and a motor drive control method capable of performing drive control of motor means in accordance with the load state of the motor means.

  In order to solve the above-described problems, the motor drive control method according to the present invention includes a control means for controlling the drive amount of the motor means when the motor means is activated and when the motor means is driven in a steady state. The drive amount of the motor means is adjusted according to the above.

  According to the motor drive control method of the present invention, the control means adjusts the drive amount of the motor means according to the startup of the motor means and the steady time when the drive state of the motor means is stable. It becomes possible to control appropriately according to a drive state. For example, when the driving load of the motor means changes greatly according to the pressure state, the driving load state of the motor means is determined based on the detection state detected by the pressure detection means, etc., and the driving is performed according to the driving load state. By adjusting the amount, it is possible to control the motor means having appropriate driving characteristics for each driving load state.

  In the motor drive control method according to the present invention, the control means adjusts the drive amount of the motor means based on the temperature information detected by the temperature detection means for detecting the temperature in the motor means. May be.

  According to the motor drive control method described above, since the control means adjusts the drive amount of the motor means based on the temperature rise detected by the temperature detection means, the drive state of the motor means is appropriately set according to the temperature state of the motor means. It becomes possible to control to. In particular, since it is possible to estimate the state of the driving load on the motor means from the temperature information in the motor means, by adjusting the drive amount according to the temperature of the motor means, the driving characteristics suitable for the driving load state Thus, the motor means can be driven.

  Further, an air compressor according to the present invention includes a compressed air generating unit that generates compressed air, a tank unit that stores the compressed air generated by the compressed air generating unit, and a mechanism for driving the compressed air generating unit. Motor means and control means for controlling the drive amount of the motor means, and the tank portion has pressure detection means for detecting the pressure state of the compressed air stored in the tank portion, and the control The means adjusts the drive amount of the motor means based on the pressure state detected by the pressure detection means.

  According to the air compressor of the present invention, since the control means adjusts the driving amount of the motor means based on the pressure state detected by the pressure detecting means, the driving state of the motor means is a state of compressed air stored in the tank portion. It becomes possible to control appropriately according to. In particular, since the driving load of the motor means varies greatly depending on the pressure state in the tank section, the driving load state of the motor means is determined based on the detection state detected by the pressure detecting means, and the driving is performed according to the driving load state. By adjusting the amount, it is possible to control the motor means having appropriate driving characteristics for each driving load state.

  In the air compressor described above, the control unit may increase or decrease the adjustment amount with respect to the drive amount in accordance with an increase in the pressure value in the tank portion detected by the pressure detection unit.

  In this way, as the pressure value in the tank unit increases, the control unit increases or decreases the adjustment amount with respect to the driving amount of the motor unit, so when the pressure value in the tank unit is low, that is, when the driving load of the motor unit is light Therefore, it is possible to reduce the adjustment of the driving amount and prevent the overshoot phenomenon due to the sudden increase in the rotational speed of the motor. Further, when the pressure value in the tank portion is high, that is, when the driving load of the motor means is heavy, by increasing the adjustment amount for the driving amount, the motor means with a large driving amount when the driving load of the motor means is heavy. It is possible to quickly increase the number of revolutions of the motor means.

  Moreover, the control means mentioned above may change the adjustment amount with respect to the drive amount according to the startup time of the motor means and the steady time when the drive state of the motor means is stable.

  Normally, when the motor means is started, the pressure in the tank section is low and the driving load of the motor means is often light. Is increased to a desired pressure value, and the driving load of the motor means is often heavy.

  For this reason, the control means changes the adjustment amount for the drive amount in accordance with the startup of the motor means and the steady state of the motor means. Thus, the increase in the rotational speed of the motor means can be mitigated and the overshoot phenomenon can be suppressed. Further, for example, when the driving load is heavy, the motor unit can be controlled quickly and reliably by increasing the adjustment amount of the driving amount to increase the rotational speed of the motor unit.

  Further, the motor means of the air compressor described above has temperature detection means for detecting the temperature in the motor means, and the control means detects the drive amount of the motor means based on the temperature information detected by the temperature detection means. You may adjust.

  According to the air compressor of the present invention, the control unit adjusts the driving amount of the motor unit based on the temperature rise detected by the temperature detection unit, so that the driving state of the motor unit is appropriately set according to the temperature state of the motor unit. It becomes possible to control to. In particular, since it is possible to estimate the state of the driving load on the motor means from the temperature information in the motor means, by adjusting the driving amount according to the temperature of the motor means, the driving characteristics suitable for the driving load state Thus, the motor unit can be driven.

  For example, it can be determined that the low temperature in the motor means is a state in which the motor means is not actively driven, so that compressed air with sufficient pressure is not yet stored in the motor means. In many cases, the driving load of the motor means is light. On the other hand, when the temperature in the motor means is high, the motor means has already been driven, and the pressure of the tank portion is raised to a desired pressure value by driving the motor means, and the driving load of the motor means is heavy. There are many cases.

  For this reason, when the control means changes the adjustment amount for the drive amount according to the temperature information of the motor means, for example, when it is determined that the drive load is light, the drive amount adjustment amount is reduced and the motor is reduced. An increase in the number of revolutions of the means can be mitigated and an overshoot phenomenon can be suppressed. Further, for example, when it is determined that the driving load is heavy based on the temperature information of the motor means, the control of the motor means is controlled by increasing the adjustment amount of the driving amount so as to speed up the rotation speed of the motor means. It becomes possible to carry out quickly and reliably.

  Furthermore, the control unit described above may increase or decrease the adjustment amount with respect to the drive amount in accordance with the increase in temperature detected by the temperature detection unit.

  Thus, in the air compressor according to the present invention, the adjustment amount with respect to the driving amount is increased / decreased in accordance with the temperature rise detected by the temperature detection unit. Therefore, when the temperature of the motor unit is low, that is, the motor unit When the driving load is light, adjustment of the driving amount can be reduced to prevent an overshoot phenomenon due to a sudden increase in the rotational speed of the motor means. Further, when the temperature of the motor means is high, that is, when the driving load of the motor means is heavy, the driving amount of the motor means can be increased by increasing the adjustment amount with respect to the driving amount. When the driving load is heavy, the motor means can be driven with a large driving amount, and the rotational speed of the motor can be quickly increased.

  According to the motor means control method of the present invention, the control means adjusts the driving amount of the motor means according to the startup of the motor means and the steady time when the driving state of the motor means is stable. It becomes possible to control appropriately according to a drive state.

  Further, according to the air compressor of the present invention, the control means increases or decreases the adjustment amount with respect to the driving amount of the motor means in accordance with the increase in the pressure value in the tank section. When the driving load is light, adjustment of the driving amount can be reduced to prevent the occurrence of an overshoot phenomenon due to a sudden increase in the rotational speed of the motor means. Further, when the pressure value in the tank portion is high and the driving load of the motor means is heavy, the driving amount of the motor means can be increased by increasing the adjustment amount with respect to the driving amount. When the load is heavy, it is possible to quickly increase the number of rotations of the motor.

  Hereinafter, an air compressor according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of an air compressor. The air compressor 1 is roughly configured by a tank unit 2, a compressed air generation unit (compressed air generation unit) 3, a motor unit (motor unit) 4, and a control circuit unit (control unit) 5.

  The tank unit 2 has a storage tank 8 for storing compressed air. The storage tank 8 stores the compressed air having a constant pressure generated by the compressed air generator 3 and is usually maintained at a pressure of about 3.5 MPa to 4.3 MPa.

  The storage tank 8 is provided with a plurality of compressed air outlets 9. In the present embodiment, a high-pressure outlet 9a for taking out high-pressure compressed air and a normal-pressure outlet 9b for taking out normal-pressure compressed air are provided. Each of the outlets 9a and 9b is provided with pressure reducing valves 10a and 10b for reducing the compressed air obtained from the respective outlets 9a and 9b to a desired pressure. In the high pressure outlet 9a, the pressure reducing valve 10a is provided. The pressure of the compressed air taken out is reduced to about 1.5 MPa to 2.50 MPa, and the pressure of the compressed air taken out by the pressure reducing valve 10b is reduced to about 0.7 MPa to 1.5 MPa at the normal pressure outlet 9b. .

  Since the compressed air in the storage tank 8 is normally maintained at a pressure of about 3.5 MPa to 4.3 MPa as described above, the compressed air taken out from the high pressure outlet 9a and the compressed air also taken out from the normal pressure outlet 9b is used. In addition, the desired pressure described above can be maintained by the pressure reducing valves 10a and 10b. In addition, an air hose (not shown) can be attached to and detached from each of the outlets 9a and 9b in order to supply the compressed air decompressed by the pressure reducing valves 10a and 10b to a driving tool such as a nail driver. Yes.

  The storage tank 8 is provided with a pressure sensor (pressure detection means) 12 for detecting the pressure in the storage tank 8. The pressure sensor 12 has a function of converting a pressure change in the storage tank 8 into an electric signal by an internal pressure sensitive element, and the detected electric signal is transmitted to the control circuit unit 5.

  FIG. 3A is a graph showing the correspondence between the output voltage detected by the pressure sensor 12 and the pressure state in the storage tank 8. In the pressure sensor 12 used in the present embodiment, when the pressure in the storage tank 8 is approximately 0 MPa (for example, atmospheric pressure or the like), an output voltage of 0.5 V is detected, and then in the storage tank 8 When the output voltage value rises in proportion to the pressure of 5 and the pressure in the storage tank 8 is 5 MPa, the output voltage of 4.5 V is detected.

  The compressed air generating unit 3 is configured to generate compressed air by reciprocating a piston provided in the cylinder and compressing air drawn into the cylinder from the intake valve of the cylinder. The compressed air is supplied to the storage tank 8 of the tank unit 2 through the connection pipe 14.

  The motor unit 4 has a role of generating a driving force for reciprocating the piston of the compressed air generating unit 3. The motor unit 4 is provided with a stator 16 and a rotor 17 for generating a driving force. The stator 16 is formed with U-phase, V-phase, and W-phase windings 16a, 16b, and 16c, and a rotating magnetic field is formed by passing a current through the windings 16a to 16c. In addition, the stator 16 is provided with a temperature detection circuit (temperature detection means) 18 for detecting the temperature of the winding 16c. A detection signal detected by the temperature detection circuit 18 is transmitted to the control circuit unit 5.

  The rotor 17 is composed of a permanent magnet, and the rotor 17 is rotated by a rotating magnetic field formed by a current flowing through the windings 16a, 16b, and 16c of the stator 16. The operation of the piston of the compressed air generating unit 3 is performed by the rotational force of the rotor 17.

  As shown in FIG. 2, the control circuit unit 5 is roughly configured by a microprocessor (MPU: Micro Processing Unit) 20, a converter circuit 21, and an inverter circuit 22.

  The microprocessor 20 is a control means for stabilizing the pressure of the compressed air in the tank unit 2 to 3.5 MPa to 4.3 MPa by performing drive control of the converter circuit 21 and the inverter circuit 22. The microprocessor 20 includes an arithmetic processing unit (CPU: Central Processing Unit), a RAM (Random Access Memory) used as a temporary storage area such as a work memory, a control processing program (a program indicating a motor drive control method) described later, A function such as a ROM (Read Only Memory) in which information indicating the correspondence between the output voltage value in the pressure sensor and the pressure value in the storage tank is recorded is realized by a one-chip LSI.

  The microprocessor 20 receives temperature information of the motor unit 4 detected by the temperature detection circuit 18 and also receives an electrical signal detected by the pressure sensor 12. On the other hand, the microprocessor 20 is configured to be able to output control information (PAM instruction, PWM instruction) to the converter circuit 21 and the inverter circuit 22. In the converter circuit 21 and the inverter circuit 22, drive control of the motor unit 4 is executed based on the control information output by the microprocessor 20.

  The converter circuit 21 is roughly configured by a rectifier circuit 24, a booster circuit 25, and a smoothing circuit 26, and so-called PAM (Pulse Amplitude Modulation) control is executed by the converter circuit 21. Here, the PAM control is a method of controlling the rotation speed of the motor unit 4 by changing the pulse height of the output voltage by the converter circuit 21. On the other hand, the inverter circuit 22 performs so-called PWM (Pulse Width Modulation) control. The PWM control is a method for controlling the rotation speed of the motor unit 4 by changing the pulse width of the output voltage.

  Compared with PWM control, PAM control has a characteristic that the motor unit 4 is less susceptible to lowering efficiency at low rotation and can cope with high rotation by increasing the voltage. It is a control method mainly used during operation and steady operation. On the other hand, the PWM control is a control method mainly used at the time of start-up or voltage drop. The microprocessor 20 executes control by suitably switching between PAM control by the converter circuit 21 and PWM control by the inverter circuit 22 according to the operating state of the air compressor 1.

  The rectifier circuit 24 and the smoothing circuit 26 of the converter circuit 21 have a role of converting into a DC voltage by rectifying and smoothing an AC power supply 28 that is a driving source of the air compressor 1. A switching element 25 a is provided inside the booster circuit 25, and has a role of controlling the amplitude of the DC voltage in accordance with a control command from the microprocessor 20. The booster circuit 25 is controlled via a booster controller 27 that has received a PAM command from the microprocessor 20. When the microprocessor 20 controls the switching element 25 a of the booster circuit 25 via the booster controller 27, the microprocessor 20 controls the converter circuit 21 by adjusting a control amount (rotation control gain) in the booster circuit 25. For example, when the rotation control gain at the time of basic control is set to “10”, gain adjustment (for example, by adjusting the rotation control gain “10” by the adjustment value +2 to the rotation control gain is performed. Is adjusted to “12”), the booster circuit 25 is controlled, and the optimum PAM control in the converter circuit 21 is executed.

  In addition, the converter circuit 21 has a function of shaping the waveform of the input current input to the booster circuit 25 into a phase and waveform similar to the input voltage and reducing wasteful power. It is also possible to function as a PFC (Power Factor Correction) circuit.

  The inverter circuit 22 has a function of converting the DC voltage pulse converted by the converter circuit 21 into positive and negative at regular intervals and converting the DC voltage into an AC voltage having a pseudo sine wave by converting the pulse width. is doing. By adjusting the pulse width, it is possible to control the rotational speed of the motor unit 4 as described above. The microprocessor 20 controls the inverter circuit 22 by adjusting the rotation control gain of the motor unit 4. When controlling the inverter circuit 22, the microprocessor 20 sets the rotation control gain at the time of basic control to “10”, for example, as in the converter circuit 21, and adjusts the gain for this rotation control gain “10”. By doing so, optimal PWM control in the inverter circuit 22 is executed.

  Next, control of the converter circuit 21 and the inverter circuit 22 in the microprocessor 20 will be described.

  As described above, the microprocessor 20 controls the converter circuit 21 and the inverter circuit 22 by adjusting the gain of the rotation control gain. The gain value to be adjusted is determined based on the pressure in the storage tank 8 obtained from the output voltage of the pressure sensor 12 and the temperature in the motor unit 4 obtained from the detection signal from the temperature detection circuit 18.

  FIG. 3B is a list showing adjustment values corresponding to the pressure values obtained from the output voltage of the pressure sensor 12. Generally, there is a difference in the driving load of the motor unit 4 when the air compressor 1 is started (starting operation) and when it is stationary (normal operation). For this reason, as shown in FIG. 3B, different adjustment values are set depending on whether the driving state of the air compressor 1 is a start-up state or a steady state.

  For example, when the pressure value in the storage tank 8 detected at the time of activation is 0 MPa to 1.0 MPa, the rotation control gain is adjusted by +2. Similarly, when the pressure value is 1.0 MPa to 2.0 MPa, the rotation control gain is adjusted by +3, and when the pressure value is 2.0 MPa to 3.0 MPa, the rotation control gain is only +4. When the pressure value is 3.0 MPa to 4.3 MPa, the rotation control gain is adjusted by +5. Further, when the pressure value in the storage tank 8 is 0 MPa to 2.0 MPa in a steady state, the rotation control gain is adjusted by +1, and when the pressure value is 2.0 MPa to 4.3 MPa, the rotation control gain is adjusted. Adjust + by +2.

  On the other hand, FIG. 3C is a list showing adjustment values corresponding to the temperature in the motor unit 4 obtained from the detection signal of the temperature detection circuit 18. As shown in FIG. 3C, the rotation control gain is not adjusted when the temperature is less than 60 degrees, and the rotation control gain is adjusted by +2 when the temperature is 60 degrees or more. In addition, the adjustment value of the rotation control gain based on the temperature is the same value at the start time and at the steady time.

  Next, a process in which the microprocessor 20 adjusts the rotation control gain when the air compressor 1 is started will be described. FIG. 4 is a flowchart showing the processing contents (motor drive control method) of the microprocessor 20 when the air compressor 1 is started.

  First, the microprocessor 20 acquires the output voltage detected by the pressure sensor 12 (step S10), and determines whether the acquired output voltage is less than 0.5V or more than 4.5V (step S10). S11). When the acquired output voltage is less than 0.5V or more than 4.5V (Yes in step S11), the pressure value of the compressed air stored in the storage tank 8 is as shown in FIG. An abnormal value (for example, 5 MPa or more) is indicated, or it can be determined that the pressure sensor 12 is out of order. In this way, when an output voltage that cannot be detected in normal use is detected, the microprocessor 20 stops driving the motor unit 4 and, if necessary, an error notification (such as an error or warning lamp) Process) is executed (step S12).

  On the other hand, when the acquired output voltage is 0.5 V or more and 4.5 V or less (No in Step S11), the pressure in the storage tank 8 is based on the output voltage detected by the pressure sensor 12. A value is determined (step S13), and an adjustment value (pressure gain) of the corresponding rotation control gain is determined from the list shown in FIG. 3B based on the obtained pressure value (step S14).

  Next, the microprocessor 20 acquires a detection signal from the temperature detection circuit 18 (step S15), and determines the temperature in the motor unit 4 based on the acquired detection signal (step S16). Then, based on the determined temperature, the microprocessor 20 determines an adjustment value (temperature gain) of the corresponding rotation control gain from the list shown in FIG. 3C (step S17).

  Thereafter, the microprocessor 20 converts the rotation control gain adjustment value (pressure gain) based on the pressure value determined in step S14 and the rotation control gain adjustment value (temperature gain) based on the temperature determined in step S17. Based on this, a rotation control gain for rotationally driving the motor unit 4 is calculated (step S18), and a control command (PAM command or PWM) is sent to the converter circuit 21 or the inverter circuit 22 according to the driving state of the air compressor 1. Command) is output (step S19).

  The converter circuit 21 that receives the PAM command or the inverter circuit 22 that receives the PWM command rotates the motor unit 4 based on the rotation control gain calculated in step S18 in accordance with the received control command (PAM command, PWM command). Drive. When the air compressor 1 is started, the PWM control by the inverter circuit 22 is often performed as described above.

  On the other hand, the processing of the microprocessor 20 when the air compressor 1 is in a steady state (during normal operation) is also executed with the same processing content as the flowchart shown in FIG. When the air compressor 1 is in steady operation, for example, the pressure value in the storage tank 8 reaches 3.0 MPa to 4.3 MPa, and the microprocessor 20 sets the pressure value in the storage tank to 3.5 MPa to 4.MPa. A state in which drive control of the motor unit 4 is performed to maintain the pressure at 3 MPa is shown. At regular time, the microprocessor 20 executes the processing shown in FIG. 4 periodically (for example, every 40 ms).

  First, the microprocessor 20 acquires the output voltage detected by the pressure sensor 12 (step S10), and determines whether the acquired output voltage is less than 0.5V or more than 4.5V (step S10). S11). When the acquired output voltage is less than 0.5V or more than 4.5V (Yes in step S11), it can be determined that the pressure sensor 12 is out of order, so that the motor unit 4 is driven. Is stopped and error processing is executed (step S12).

  On the other hand, when the acquired output voltage is 0.5 V or more and 4.5 V or less (No in Step S11), the pressure in the storage tank 8 is based on the output voltage detected by the pressure sensor 12. A value is determined (step S13), and an adjustment value (pressure gain) of the corresponding rotation control gain is determined from the list shown in FIG. 3B based on the obtained pressure value (step S14).

  Next, the microprocessor 20 acquires a detection signal from the temperature detection circuit 18 (step S15), and determines the temperature in the motor unit 4 based on the acquired detection signal (step S16). Then, based on the determined temperature, the microprocessor 20 determines an adjustment value (temperature gain) of the corresponding rotation control gain from the list shown in FIG. 3C (step S17).

  Thereafter, the microprocessor 20 uses the rotation control gain adjustment value (pressure gain) based on the pressure value determined in step S14 and the rotation control gain adjustment value (temperature gain) based on the temperature determined in step S17. Then, a rotation control gain for rotationally driving the motor unit 4 is calculated (step S18), and a control command (PAM command or PWM command) is given to the converter circuit 21 or the inverter circuit 22 according to the driving state of the air compressor 1. Is output (step S19).

  The converter circuit 21 that receives the PAM command or the inverter circuit 22 that receives the PWM command rotates the motor unit 4 based on the rotation control gain calculated in step S18 in accordance with the received control command (PAM command, PWM command). Drive. When the air compressor 1 is in a steady state (normal operation), the PAM control by the converter circuit 21 is often performed as described above.

  As described above, the microprocessor 20 determines the pressure value in the storage tank 8 and the temperature in the motor unit 4, and changes the driving amount (rotation control gain) of the motor unit 4 based on the determined value. Thus, it is possible to perform appropriate drive control of the motor unit according to the load state of the motor unit 4.

  Specifically, when the pressure in the storage tank 8 is low and the driving load for driving the motor unit 4 is low, such as when the air compressor 1 is started, the rotation control gain is higher than that when the pressure value is high. Rotation control gain using a low adjustment value (in FIG. 3B, adjustment value +2 of 0 MPa to 1.0 MPa is lower than adjustment value +5 of 3.0 MPa to 4.3 MPa). Is calculated. For this reason, the motor unit 4 is driven with a high rotation control gain in a state where the driving load is low, and the motor unit 4 rises significantly exceeding a predetermined rotation speed (for example, 3300 rpm) (so-called overshoot). It becomes possible to prevent.

  On the other hand, when the pressure value is increased by driving the motor unit 4 in a state where the pressure in the storage tank 8 is high (for example, the pressure value is 3.0 MPa to 3.5 MPa), the pressure value is already high. Therefore, the driving load for driving the motor unit 4 is high. Thus, in a situation where the driving load is high, an adjustment value higher than that when the pressure value is low (adjustment value of 3.0 MPa to 4.3 MPa + 5 rather than adjustment value +2 of 0 MPa to 1.0 MPa in FIG. 3B) By calculating the rotation control gain using a higher adjustment value, the motor unit 4 can be actively driven with a high rotation control gain when the driving load is high, and the storage tank 8 can be quickly operated. It is possible to increase the internal pressure value to a predetermined pressure value (for example, 4.0 MPa).

  Similarly, when the temperature of the motor unit 4 is a predetermined temperature, for example, 60 degrees or more, the motor unit 4 is already driven, and if the motor unit 4 is further driven, the driving load becomes heavy. Judgment can be made. For this reason, when the temperature of the motor unit 4 is high, the motor unit 4 is actively driven with a high rotation control gain by calculating the rotation control gain using the adjustment value shown in FIG. be able to. For this reason, for example, the process of increasing the pressure value in the storage tank 8 to a predetermined pressure value (for example, 4.0 MPa), or the rotation speed of the motor unit 4 to a predetermined rotation speed (for example, silent power saving mode (1800 rpm)) To the normal operation mode (3300 rpm)) can be quickly executed.

  Although the air compressor and motor drive control method according to the present invention have been described in detail with reference to the drawings, the air compressor and motor drive control method according to the present invention are not limited to those described above. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention.

  For example, as shown in the flowchart of FIG. 4, the air compressor 1 according to the above-described embodiment adjusts the rotation control gain based on both the pressure value of the storage tank 8 and the temperature of the motor unit 4. It is the composition to do. However, the rotation control gain is not necessarily adjusted based on both pressure and temperature values. For example, the rotation control gain may be adjusted based only on the pressure value of the storage tank 8, or the rotation control gain may be adjusted based only on the temperature of the motor unit 4. .

  Further, the air compressor 1 according to the present embodiment is configured to adjust the rotation control gain corresponding to the pressure value of the storage tank 8 in accordance with the adjustment values in the list shown in FIG. The value of the adjustment value corresponding to the pressure value is not limited to the value shown in FIG. 3B, and the rotation control gain may be increased or decreased based on another adjustment value. Similarly, even when the rotation control gain corresponding to the temperature of the motor unit 4 is adjusted, the value of the adjustment value is not limited to the value shown in FIG. The rotation control gain may be increased or decreased based on the above.

  Further, in the above-described embodiment, the case where the motor drive control method according to the present invention is used for the air compressor 1 has been described. However, the motor drive control method according to the present invention is not necessarily limited to the motor unit of the air compressor 1. However, the present invention is not limited to drive control No. 4, and can be used for drive control of motor means in other products.

It is a block diagram which shows schematic structure of the air compressor which concerns on embodiment. It is a block diagram which shows the control circuit part of the air compressor which concerns on embodiment. (A) is the graph which showed the relationship between the output voltage detected in a pressure sensor, and the pressure value in the storage tank corresponding to an output voltage, (b) is the rotation corresponding to the pressure value of a storage tank. It is a table | surface which shows the adjustment value of a control gain, (c) is a table | surface which shows the adjustment value of the rotation control gain corresponding to the temperature of a motor part. It is the flowchart which showed the processing content (motor drive control method) of the microprocessor which concerns on embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Air compressor 2 ... Tank part 3 ... Compressed air production | generation part (compressed air production | generation means)
4 ... Motor part (motor means)
5 ... Control circuit section (control means)
DESCRIPTION OF SYMBOLS 8 ... Storage tank 9 ... Compressed air outlet 9a ... High pressure outlet 9b ... Normal pressure outlet 10a, 10b ... Pressure reducing valve 12 ... Pressure sensor (pressure detection means)
14 ... Connection pipe 16 ... Stator 16a, 16b, 16c ... Winding 17 ... Rotor 18 ... Temperature detection circuit (temperature detection means)
DESCRIPTION OF SYMBOLS 20 ... Microprocessor 21 ... Converter circuit 22 ... Inverter circuit 24 ... Rectifier circuit 25 ... Booster circuit 25a ... Switching element 26 ... Smoothing circuit 27 ... Booster controller 28 ... AC power supply

Claims (7)

The control means for controlling the drive amount of the motor means adjusts the drive quantity of the motor means according to the startup time of the motor means and the steady time when the drive state of the motor means is stable. Motor drive control method. The control means includes
The motor drive control method according to claim 1, wherein the drive amount of the motor means is adjusted based on temperature information detected by a temperature detection means for detecting a temperature in the motor means. Compressed air generating means for generating compressed air;
A tank section for storing the compressed air generated by the compressed air generating means;
Motor means for driving the compressed air generating means;
Control means for controlling the drive amount of the motor means,
The tank part has pressure detection means for detecting the pressure state of the compressed air stored in the tank part,
The air compressor characterized in that the control means adjusts the driving amount of the motor means based on the pressure state detected by the pressure detection means. The control means includes
4. The air compressor according to claim 3, wherein an adjustment amount with respect to the drive amount is increased or decreased according to an increase in a pressure value in the tank portion detected by the pressure detection unit. The control means includes
5. The air compressor according to claim 3, wherein an adjustment amount for the drive amount is changed in accordance with a start time of the motor unit and a steady state in which the drive state of the motor unit is stable. . The motor means includes
Having temperature detecting means for detecting the temperature in the motor means;
The air compressor according to any one of claims 3 to 5, wherein the control unit adjusts a driving amount of the motor unit based on temperature information detected by the temperature detection unit.   The air compressor according to claim 6, wherein the control unit increases or decreases an adjustment amount with respect to the drive amount in accordance with an increase in temperature detected by the temperature detection unit.

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