Compressor and control method thereof

Abstract

The invention provides a compressor which can effectively reduce stop pressure according to operation cycle time regardless of continuous operation based on an unloading function or a speed change function based on an inverter. The compressor (100) comprises an electric motor (104), a compressor body (103) driven by the electric motor (104) to generate compressed gas (109), a container (10) for storing the compressed gas (109) generated by the compressor body (103), a pressure detector (112) for detecting the pressure of the compressed gas (109) in the container (107), and a control part (115) for controlling the power supplied to the electric motor (104) according to the detection result of the pressure detector (112). The control unit (115) determines whether or not a pressure increase / decrease period (TOFF + TON) for the pressure reaching the stop pressure (202), the pressure decreasing to the start pressure (204), and the pressure reaching the stop pressure (202) exceeds a first period threshold value (210), and decreases the stop pressure by a first pressure change value (PECO or 2PECO) when the pressure increase / decrease period exceeds the first period threshold value (210).

Description

Technical Field

[0001] This invention relates to compressors and their control methods. Background Technology

[0002] Gas compressors are known to generate compressed gas that is used as a power source in production lines, or as an air source for machine tools, presses, blowers, etc. Additionally, there are box-type gas compressors that have multiple compressor bodies and electric motors driving them, with control circuits, control panels, etc., integrated into a single housing, achieving space savings. In such gas compressors, reducing power consumption is required; one solution is to lower the stop pressure that halts the operation of the gas compressor.

[0003] The background technology of this invention is described in patent documents 1 and 2.

[0004] In Patent Document 1, a reciprocating compressor with unloading function is equipped with a control that switches between intermittent operation control and continuous operation control in a manner that keeps the operation cycle time above a specified reference operation cycle time T0.

[0005] Patent document 2 includes a control that can reduce the stop pressure in accordance with the calculation of container volume and air consumption.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2013-117182

[0009] Patent Document 2: Japanese Patent Application Publication No. 2012-154294 Summary of the Invention

[0010] The technical problem that the invention aims to solve

[0011] Patent Document 1 describes a compressor that reduces the compressor load and power consumption by switching between intermittent and continuous operation control using an unloading function. However, in the compressor described in Patent Document 1, the motor stops when the reference operating cycle time is reached, even if the stop pressure has not been reached, thus stopping the operation of the compressor body. While this reduces power consumption, it is not a control that lowers the stop pressure. Furthermore, because it is not a control that lowers the stop pressure, it is also not a control that raises the stop pressure again in accordance with the operating cycle time.

[0012] For compressors that lack unloading functionality or variable speed control via inverters, continuous operation control is not possible. Therefore, for compressors without variable speed control, intermittent operation control is required to reduce power consumption.

[0013] Furthermore, the technology described in Patent Document 2 does not involve a control that reduces the stop pressure by a certain amount in accordance with the constantly changing operating cycle time. Also, it does not involve a control that increases the previously reduced stop pressure again in accordance with the operating cycle time.

[0014] Because the stop pressure is changed only when the container volume is changed, it is not changed during normal use, thus allowing for reduced power consumption during normal use.

[0015] The purpose of this invention is to provide a compressor and its control method that can effectively reduce the stop pressure in accordance with the operating cycle time, regardless of whether it has a continuous operation achieved by unloading function or a variable speed function achieved by frequency converter.

[0016] Technical means to solve the problem

[0017] To achieve the above objectives, the present invention is configured in the following manner.

[0018] A compressor, characterized in that it comprises: an electric motor; a compressor body driven by the electric motor to generate compressed gas; a container for storing the compressed gas generated by the compressor body; a pressure detector for detecting the pressure of the compressed gas in the container; and a control unit for controlling the electrical power supplied to the electric motor based on the detection result of the pressure detector; wherein the control unit determines whether the pressure increase / decrease cycle from the pressure detector's detection result reaching a stop pressure to a start pressure until the stop pressure is reached again exceeds a first cycle threshold, and if the pressure increase / decrease cycle exceeds the first cycle threshold, the stop pressure is reduced by a first pressure change value.

[0019] Another method for controlling a compressor that stores compressed gas generated by a compressor body driven by an electric motor in a container, detects the pressure of the compressed gas in the container using a pressure detector, and controls the electrical power supplied to the electric motor based on the detection result, is characterized in that: it is determined whether the pressure increase / decrease cycle from the pressure detector reaching a stop pressure to a start pressure until the stop pressure is reached again exceeds a first cycle threshold, and if the pressure increase / decrease cycle exceeds the first cycle threshold, the stop pressure is reduced by a first pressure change value.

[0020] Invention Effects

[0021] According to the present invention, a compressor and its control method are provided that can effectively reduce the stop pressure based on the operating cycle time, even for compressors that do not have unloading function for continuous operation control and variable speed control for variable speed control implemented by frequency converter. Attached Figure Description

[0022] Figure 1 This is a conceptual diagram of the compressor as described in Embodiment 1 of the present invention.

[0023] Figure 2 This is a conceptual diagram showing the time waveform of the pressure of a compressor according to one embodiment of the present invention.

[0024] Figure 3 This is a conceptual diagram illustrating the operating state flow of the compressor in Embodiment 1 of the present invention.

[0025] Figure 4 This is a functional block diagram of the control circuit board (control unit) in Embodiment 1 of the present invention.

[0026] Figure 5 This is a conceptual diagram of the compressor as described in Embodiment 2 of the present invention.

[0027] Figure 6 This is a conceptual diagram showing the time waveform of the pressure in the compressor of Embodiment 2 of the present invention.

[0028] Figure 7 This is a functional block diagram of the control circuit board (control unit) in Embodiment 3 of the present invention.

[0029] Figure 8 This is a conceptual diagram illustrating the operating state flow of the compressor in Embodiment 5 of the present invention.

[0030] Figure 9 This is a conceptual diagram illustrating the operating state flow of the compressor in Embodiment 6 of the present invention.

[0031] Figure 10 This is a conceptual diagram illustrating the operating state flow of the compressor in a modified example of Embodiment 6 of the present invention.

[0032] Figure 11 This is a conceptual diagram illustrating the operating state flow of the compressor in Embodiment 7 of the present invention. Detailed Implementation

[0033] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0034] Example

[0035] (Example 1)

[0036] In this embodiment 1, we will take a product with a compressor body as an example. The compression method is to form a compression chamber between a fixed scroll component and a rotating scroll component, and to compress air through rotational motion.

[0037] Figure 1This is a conceptual diagram of the compressor 100 according to Embodiment 1 of the present invention. Embodiment 1 consists of a single-stage compressor body 103. Air 101 supplied from outside the compressor 100 passes through a filter 102 and is supplied to the compressor body 103. The compressor body 103 is driven by an electric motor 104, and the compressed air passes through a check valve 105, an aftercooler 106, a container 107, and a dryer 108 to be supplied to the outside as compressed air (compressed gas) 109.

[0038] The compressor 100 is started / stopped by switch 110, and the components of each part of the compressor 100 are controlled by control circuit board 111. The compressor body 103 is intermittently controlled by sending a command from control circuit board 111 to magnetic switch 113 in response to the pressure detected by pressure sensor (pressure detector) 112.

[0039] The control unit 115 is formed by the control circuit board 111 and the magnetic switch 113. The control unit 115 controls the power (electrical power) supplied to the motor 104 in accordance with the detection result of the pressure detector 112.

[0040] Figure 2 This is a conceptual diagram showing the time waveform of the pressure in the compressor 100 of Embodiment 1 of the present invention, with the vertical axis representing pressure and the horizontal axis representing time.

[0041] Figure 2 In the process, compressor 100 starts operating at the beginning of operation, and the pressure gradually rises until it stops at the specified pressure (P). MAX )202 stops compressor 100. After compressor 100 is stopped, the pressure decreases until it reaches the starting pressure (P). MIN The time until restarting is taken as the stopping cycle (circle) time (T). OFF 205 count. The pressure will then be reached again at the stop pressure (P). MAX The time of 202 is used as the cycle time (T) ON )206 count.

[0042] Use the stop cycle time (T) OFF )205 and operating cycle time (T) ON The number obtained by adding 206 (pressure increase / decrease cycle) and the ECO mode cycle time (T) ECO The period time judgment formula 207 (T) is compared with 210 (first period threshold). OFF +T ON >T ECO The judgment is made based on the time (T) of the ECO mode cycle. ECO In the case of 210, the stopping cycle time (T) is used. OFF)205 and operating cycle time (T) ON )206 Comparison of ON-OFF (Run-Stop) Time Judgment Formula 208 (T) OFF >T ON The judgment is then made. Afterwards, the pressure change value (P) is determined. ECO )209, and reflects the changed stop pressure (P') after the time 206 of the next operating cycle. MAX 203.

[0043] Additionally, pressure is stopped until the change is reached (P'). MAX The cycle time judgment formula 207 up to 203 determines that it is less than the ECO mode cycle time (T). ECO In the case of 210, the stopping pressure stabilization judgment formula 211 (T) is used. OFF +T ON <C ST *T ECO Determine if a change is needed to the stop pressure (P') after the change. MAX 203. C ST *T ECO It is the threshold of the second cycle. C ST It is a tolerance that can be set arbitrarily, for example, it can be set to within 5%.

[0044] Figure 3 This is a conceptual diagram illustrating the operating state flow of the compressor 100 according to Embodiment 1 of the present invention.

[0045] Figure 3 In the process, control begins according to step 301. Compression operation begins in step 302, and the ECO mode control cycle continues in step 303. When compression operation begins in step 302, the control circuit board 111 executes... Figure 3 The process is shown below.

[0046] For the stopping cycle time (T) OFF ) and operating cycle time (T) ON Does the total value exceed the ECO mode cycle time (T)? ECO The cycle time is determined using cycle time judgment formula 207 in cycle time judgment step 304. Stop cycle time (T) OFF ) and operating cycle time (T) ON The total value exceeds the ECO mode cycle time (T). ECO In the case of setting the ECO flag in step 308, proceed to step 309 to determine the ON-OFF (run-stop) time.

[0047] In step 309, the ON-OFF time judgment formula 208 is used to determine the stopping cycle time (T).OFF ) and operating cycle time (T) ON The comparison is performed. In step 309, the stopping cycle time (T) is... OFF ) compared to the operating cycle time (T) ON If the timeframe is short, proceed to step 310 and determine the stop pressure P' after the change. MAX (P') MAX =P MAX -P ECO ).

[0048] In step S309, the stop cycle time (T) OFF ) compared to the operating cycle time (T) ON If the pressure is long, proceed to step 311 and decide to change the stop pressure P'. MAX (P') MAX =P MAX -2P ECO ).

[0049] After processing in step 310 or step 311, proceed to step 305, and use the stopping pressure stabilization judgment formula 211 to determine the stopping cycle time (T). OFF ) and operating cycle time (T) ON Is the total value of ) lower than the ECO mode cycle time (T)? ECO Multiply by the stabilization factor (C) ST The value obtained (second cycle threshold). If it is "Yes" (lower than), the stop pressure (P) remains unchanged. MAX ) or the stop pressure after the change (P') MAX Return the value of ) in the loop.

[0050] In step 305, if the result is "No" (not lower than), proceed to step 306 to determine whether the ECO flag has been set.

[0051] If the ECO flag is not set in step 306, return to the loop. If the ECO flag is set in step 306, proceed to step 312, make the change, and then stop the pressure (P'). MAX Resetting (P') MAX = P' MAX +P ECO That is, to make the stopping pressure (P) MAX Increase the pressure change value (P) ECO ).

[0052] Next, proceed to step 313 to modify and stop the pressure (P'). MAX Is it related to the initial stopping pressure (P)? MAX The same stop pressure is used for judgment. The stop pressure after the change (P')MAX ) and the initial stopping pressure (P) MAX If the conditions are the same, proceed to step 314, delete the ECO flag, and return to the loop. The stop pressure (P') is changed in step 313. MAX ) and the initial stopping pressure (P) MAX In different cases, return directly to the loop.

[0053] The processes in steps 304-306 and 308-314 are repeated while the compressor 100 is running, and end when the compressor 100 stops running (step 307).

[0054] according to Figure 3 As shown in the flowchart, the configuration is such that if the pressure increase / decrease cycle (T) OFF +T ON During the ECO mode cycle time T ECO tolerance C ST If the pressure is within the specified range, the stopping pressure P will not be changed. MAX The settings.

[0055] Figure 4 This is a functional block diagram of the control circuit board 111 in Embodiment 1.

[0056] Figure 4 In the control circuit board 111, there are pressure control unit 1110, cycle time judgment unit 1111, stop pressure change unit 1112, and ECO flag setting unit 1113.

[0057] The pressure control unit 111 executes the following based on the cycle time determined by the cycle time determination unit 1111, the stop pressure changed by the stop pressure change unit 1112, and the ECO flag setting unit 1113. Figure 3 The operating status flow of the compressor 100 is shown.

[0058] Embodiment 1 of the present invention, as described above, is configured to operate within a cycle time (T). OFF T ON Adjust the stopping pressure P accordingly. MAX Therefore, a compressor and its control method can be developed that can effectively reduce the stop pressure in accordance with the operating cycle time, regardless of whether it has an unloading function to achieve continuous operation or a frequency converter to achieve variable speed function.

[0059] Set to P ECO Or 2P ECO The change value is defined as the first pressure change value, and will be set to P. ECO The change value is defined as the second pressure change value.

[0060] In the above example, the control unit 115 increases the stop pressure by a predetermined value when the pressure increase / decrease cycle is less than a predetermined time. However, in Embodiment 1, a structure is also included that divides the stop pressure into multiple modes and increases the predetermined value for each mode according to the ratio of the stop cycle time to the operation cycle time of the pressure increase / decrease cycle.

[0061] In addition, the stabilization coefficient (C) ST It can be set arbitrarily for each product (compressor).

[0062] Alternatively, the control unit 115 may include a frequency converter or a speed controller.

[0063] (Example 2)

[0064] Next, Embodiment 2 of the present invention will be described.

[0065] Example 2 is an example of reducing power consumption by counting the operation cycle time of continuous operation control as the stop cycle time in the case of compressor 100 with frequency converter.

[0066] Figure 5 This is a conceptual diagram of the compressor 100A according to Embodiment 2 of the present invention.

[0067] Figure 1 In the case of compressor 100 in Embodiment 1, which is a fixed-speed compressor, compressor 100A in Embodiment 2 is not equipped with magnetic switch 113. Control circuit board 111A is also used as a frequency converter, and signals are supplied to motor 104 from control circuit board 111A.

[0068] In Embodiment 1, the control circuit board 111 and the magnetic switch 113 form the control unit 115. In Embodiment 2, the control circuit board 111A, which also serves as a frequency converter, corresponds to the control unit 115.

[0069] Figure 6 This is a conceptual diagram showing the time waveform of the pressure in the compressor 100A of Embodiment 2 of the present invention, with the vertical axis representing time and the horizontal axis representing time.

[0070] Figure 6 In the diagram, the dashed line represents the rotational speed waveform of the motor controlled by the control circuit board (which also functions as a frequency converter) 111A; the dashed line represents the pressure waveform of the constant speed unit (Example 1); and the solid line represents the pressure waveform of the control circuit board 111A (Example 2). The pressure waveform of the constant speed unit (Example 1) (dashed line) during the initial stop cycle (T...) OFF )205 and 206 operating cycle time (T) ON The waveform of the pressure after 206 is the same as that of the inverter machine (Example 2).

[0071] like Figure 6 As shown by the dotted line, when the motor 104 starts, it accelerates to its maximum speed to generate compressed gas. Then, the rotational speed is changed according to the pressure to adjust the amount of compressed gas generated.

[0072] The speed of motor 104 reaches the set lower limit value RS. MIN At 213, instead of continuing to decrease, the rotation stops. This is a minimum speed (lower limit RS) set to protect the compressor body 103. MIN 213).

[0073] Even if the following limits RS MIN 213 is running, and the pressure still reaches P. MAX In this case, the motor 104 is stopped rotating, and the pressure is allowed to reach P. MIN .

[0074] The operating status flow of compressor 103 is the same as that in Example 1. Figure 3 The same. Furthermore, the functional modules of control circuit board 111A (omitting the frequency converter) are the same as those in Embodiment 1. Figure 4 Same (but magnetic switch 113 is omitted).

[0075] In Example 2, the pressure of compressor 103 also fluctuates between stop pressure and recovery pressure, thus enabling energy saving by using cycle time as shown in Example 1.

[0076] That is, according to Embodiment 2, a compressor and its control method are capable of effectively reducing the stop pressure in accordance with the operating cycle time, regardless of whether it has a continuous operation achieved by unloading function or a variable speed function achieved by frequency converter.

[0077] (Example 3)

[0078] Next, Embodiment 3 of the present invention will be described.

[0079] Figure 7 This is a functional block diagram of the control circuit board 111 in Embodiment 3. Figure 4 The functional modules in Embodiment 1 shown are Figure 7 The difference between the functional modules shown is that, Figure 7 A user setting unit 114 has been added, which can, from outside the control circuit board 111, enable the pressure control unit 1110 to invalidate part or all of the judgment formula, or to set parameters (first cycle threshold 210, stabilization coefficient C) according to the user's settings. ST First pressure change value (P) ECO Or 2P ECO ), second pressure change value (P) ECO ECO mode cycle time T ECOChange part or all of it to any value.

[0080] The operation of compressor 100 can be appropriately modified through user settings.

[0081] The other structures and operations are the same as in Embodiment 1 or Embodiment 2.

[0082] According to Embodiment 3, the same effect as in Embodiment 1 can be obtained, and the user can appropriately correct the operation of the compressor 100.

[0083] (Example 4)

[0084] Next, Embodiment 4 of the present invention will be described.

[0085] In Examples 1 and 2, the stopping cycle time (T) OFF )205 and operating cycle time (T) ON )206. Distinguish and compare them to make a judgment.

[0086] In this regard, in Example 4, the stopping cycle time (T) is not distinguished. OFF )205 and operating cycle time (T) ON )206, by adjusting the cycle time (stop cycle time (T) OFF 205+ Operation cycle time (T) ON )206) and ECO mode cycle time (T) ECO )210 compares to achieve simple control.

[0087] The other structures and operations are the same as in Example 1 or Example 2.

[0088] According to Example 4, a compressor and its control method are provided that can meet the requirements with simple control, and can effectively reduce the stop pressure in accordance with the operating cycle time, regardless of whether it has an unloading function to achieve continuous operation or a variable speed function to achieve variable speed.

[0089] (Example 5)

[0090] Next, Embodiment 5 of the present invention will be described.

[0091] Example 1 is about determining the stop cycle time (T) in the pressure increase / decrease cycle. OFF ) and operating cycle time (T) ON Example 5 is an example where the first cycle threshold 210 is determined by averaging the time of multiple pressure increase / decrease cycles instead of using one pressure increase / decrease cycle.

[0092] Figure 8This is a conceptual diagram illustrating the operating state flow of the compressor in Embodiment 5 of the invention.

[0093] Figure 8 The operational status flow of Example 3 shown is as follows: Figure 3 The difference between the operational status flow of Embodiment 1 shown is that, Figure 7 The process in Figure 3 Multiple cyclic execution steps 303A and averaging steps 303B have been added between steps 303 and 304 of the process. Figure 8 Other steps and Figure 3 The steps are the same.

[0094] In step 303A, multiple cycles are executed, and in step 303B, the stop cycle time (T) executed in the multiple cycles is calculated. OFF The average value of ) and the cycle time (T) executed in multiple cycles. ON The average value of ) is used in subsequent steps as the stopping cycle time (T). OFF ) and operating cycle time (T) ON ).

[0095] The number of cycles can be set to any value greater than 2.

[0096] According to Example 5, the same effect as in Example 1 can be obtained, and by averaging the pressure fluctuations, a compressor and its control method capable of stable pressure control can be realized.

[0097] (Example 6)

[0098] Next, Embodiment 6 of the present invention will be described.

[0099] Example 6 is based on Example 1, but with a stopping pressure P'. MAX Examples of cases where the lower limit value is specified.

[0100] Figure 9 This is a conceptual diagram illustrating the operating state flow of the compressor in Example 6. Figure 9 The operating status process shown is consistent with Figure 3 The difference in the operational flow shown is that, Figure 9 The operational status flow shown is in Figure 3 Step 317 was added between steps 308 and 309, step 315 was added between steps 306 and 312, and step 316 was added between steps 315 and 314.

[0101] The necessary minimum pressure is determined by the device used by the user of the compressed gas, and is therefore set to be no lower than this pressure.

[0102] In step 317, the stopping pressure P' is determined. MAX Not lower than the lower limit of the stop pressure (and P) MIN The lower limit of the pressure difference C LMT (P) MIN +C LMT Stop pressure P' MAX If the pressure is below the lower limit, the stopping pressure P' will not be changed. MAX The settings proceed from step 317 to the next step 305.

[0103] Stop pressure P' in step 317 MAX Not lower than the lower limit of the stop pressure (and P) MIN The lower limit of the pressure difference C LMT Proceed to step 309 if the condition is met.

[0104] Next, step 315 will be explained.

[0105] In step 315, the period time T is determined. OFF +T ON It won't be too short. Cycle time T OFF +T ON If the cycle time is too short, the opening and closing frequency of the magnetic switch (electromagnetic switch) 113 increases, thus shortening its lifespan. In order to protect the magnetic switch (electromagnetic switch) 113 (extend its lifespan), the stopping pressure needs to be controlled in a way that ensures the cycle time is not too short.

[0106] Therefore, in step 315, T is determined. OFF +T ON Is it less than C? RS *T ECO In less than C RS *T ECO Proceed to step 316 and set P' MAX Set as P MAX .

[0107] The other actions are the same as in Example 1.

[0108] Example 6 has a smaller energy-saving effect than Example 1, but it can balance user convenience and device reliability.

[0109] (Variation Example 1)

[0110] Next, a modified example of Example 6 will be described.

[0111] Figure 10 This is a conceptual diagram illustrating the operating state flow of the compressor in a modified example of Embodiment 6.

[0112] Figure 9 The example shown is similar to Figure 10The difference in the examples shown is that, Figure 10 The middle part is omitted Figure 9 Steps 315 and 316 are shown.

[0113] In steps 315 and 316, the period time T is made... OFF +T ON The process is not too short, but if the protection of the magnetic switch (electromagnetic switch) 113 is not required (long life), steps 315 and 316 can be omitted.

[0114] (Example 7)

[0115] Next, Embodiment 7 of the present invention will be described.

[0116] Example 7 is an example of Example 1 with the addition of a thermal safety mode.

[0117] Figure 11 This is a conceptual diagram illustrating the operational flow of the compressor 100 in Embodiment 7. Additionally, Figure 11 In this context, HS represents thermal safety, AT represents ambient temperature, and PS represents pressure switch.

[0118] Figure 11 In step 401, the compressor is started, and in step 402, the compressor begins to run. In step 403, it is determined whether the ECO mode is valid or invalid. If valid, the process proceeds to the ECO mode cycle in step 413. If the ECO mode is invalid in step 403, the process proceeds to the pressure switch control cycle in step 404.

[0119] In step 405, compressor 100 is controlled using pressure switch control (PS mode control). Next, in step 406, it is determined whether the thermal safety mode is active or inactive. If active, the process proceeds to step 421. If inactive in step 406, the process proceeds to step 407, which determines whether to notify of an abnormal ambient temperature. If no abnormal ambient temperature is not notified in step 407, the process proceeds to step 408, which determines whether to issue a high ambient temperature alarm. If no high ambient temperature alarm is not notified in step 408, the process proceeds to step 409, ending in step 410 if the pressure switch control cycle is terminated. If the compressor is not stopped in step 409, the process returns to step 404 to continue pressure switch control.

[0120] If the ambient temperature is determined to be greater than 45℃ in step 407, an abnormality flag is set in step 411, the pressure switch control cycle is exited, and the compressor 100 is stopped.

[0121] If the ambient temperature AT is determined to be greater than 40℃ in step 408, an alarm sign is set in step 412, an alarm is issued, and pressure switch control continues.

[0122] If the ECO mode is valid in step 403, proceed to step 413 to begin the ECO mode control cycle. In step 414, determine whether the thermal safety mode is valid or invalid. If valid, proceed to step 421 for the thermal safety mode; if invalid, proceed to step 415 to perform the usual ambient temperature anomaly / alarm assessment.

[0123] In step 415, it is determined whether an abnormal temperature occurs where the ambient temperature AT exceeds 45°C. If the temperature is abnormal, an abnormality flag is set in step 417, the ECO mode control cycle is exited, and the compressor 100 is stopped.

[0124] If the ambient temperature AT is below 45°C in step 415, proceed to step 416 to determine if an abnormal temperature has occurred where the ambient temperature AT exceeds 40°C. If it exceeds 40°C, set an alarm flag in step 418. Then, issue an alarm and continue ECO mode control.

[0125] If the ambient temperature AT is below 40°C in step 416, proceed to step 419 to control the compressor 100 using ECO mode. Then, in step 420, execute the ECO mode control cycle, and return to step 413 without stopping the compressor 100 to continue ECO mode control.

[0126] If the thermal safety mode is effective in step 406 or step 414, proceed to step 421 to determine if the ambient temperature AT is greater than 45°C. If it is greater than 45°C, proceed to step 422 to control the AT45 mode.

[0127] In step 422, the AT45 mode control cycle begins, and in step 423, the compressor 100 is controlled using the AT45 mode control.

[0128] If the ambient temperature AT is determined to be less than 45°C in step 424, the AT45 mode control loop exits and proceeds to step 426. If the ambient temperature AT is not determined to be less than 45°C in step 424, the AT45 mode continues. That is, in step 425, the system returns to step 422 and continues AT45 mode control until the AT45 mode control loop ends.

[0129] In step 426, if the thermal safety mode is effective in steps 406 and 414, and the ambient temperature is determined to be less than 45°C and greater than 40°C, the process transitions to AT40 mode control step 427, initiating the AT40 mode control cycle. Then, in step 428, the compressor 100 is controlled using AT40 mode control.

[0130] If the ambient temperature AT is determined to be less than 40℃ in step 429, the AT40 mode control loop exits. If the ambient temperature AT is not determined to be less than 40℃ in step 429, proceed to step 430. If the ambient temperature AT is determined to be greater than 45℃ in step 430, the AT40 mode control loop exits, returns to step 422, and proceeds to the AT45 mode control loop. If the ambient temperature AT is not determined to be greater than 45℃ in step 430, proceed to step 431 and continue in AT40 mode. In step 431, the AT40 mode control loop ends, returns to 427, and continues AT40 mode control.

[0131] If the ambient temperature AT is not greater than 40°C in step 426, then in step 432, it is determined whether to return to the ECO mode control cycle or the pressure switch control cycle.

[0132] Example 7 achieves the same effect as Example 1, and is configured to operate the compressor 100 in a thermal safety mode when the ambient temperature exceeds a certain temperature, and to operate the compressor 100 by setting an error flag or alarm flag corresponding to the ambient temperature AT when the thermal safety mode is not effective. Therefore, a compressor and its control method that can achieve safer and more stable operation can be realized.

[0133] The above embodiments are merely specific examples that help to understand the concept of the present invention and are not intended to limit the scope of the present invention. Various constituent elements can be added, deleted, or modified within the scope of the spirit of the present invention.

[0134] The various functional units described in the above embodiments can also be implemented using circuits. A circuit can be a dedicated circuit that performs a specific function, or it can be a general-purpose circuit such as a processor.

[0135] At least some of the processes described in the above embodiments can also be implemented using a general-purpose computer as the basic hardware. The program implementing the above processes can be provided stored on a computer-readable recording medium. The program is stored on the recording medium as an installable or executable file. The recording medium can be a disk, optical disk (CD-ROM, CD-R, DVD, etc.), magneto-optical disk (MO, etc.), semiconductor memory, etc. The recording medium can be any recording medium capable of storing programs and readable by a computer. Alternatively, the program implementing the above processes can be stored on a computer (server) connected to a network such as the Internet and downloaded to a computer (client) via the network.

[0136] Explanation of reference numerals in the attached figures

[0137] 100, 100A…Compressor, 101…Air, 102…Filter, 103…Compressor body, 104…Motor, 105…Check valve, 106…Aftercooler, 107…Container, 108…Dryer, 109…Compressed air (compressed gas), 110…Switch, 111, 111A…Control circuit board, 112…Pressure sensor (pressure detector), 113…Magnetic switch, 114…User setting unit, 115…Control unit, 201…Start of operation, 202…Stop pressure (P) MAX ), 203……Stop pressure after change (P') MAX ), 204……Starting pressure (P) MIN ), 205……stopping cycle time (T) OFF ), 206……Operating cycle time (T) ON ), 207……Cycle time judgment formula, 208……ON-OFF (operation-stop) time judgment formula, 209……Pressure change value (P) ECO ), 210……ECO mode cycle time (T) ECO(First cycle threshold), 211...Stop pressure stabilization judgment, 301...Process start step, 302...Compressor start step, 303...ECO mode control step, 304...Cycle time judgment step, 305...Stop pressure stabilization judgment step, 306...ECO flag presence / absence judgment step, 307...Process end step, 308...ECO flag setting step, 309...ON-OFF time judgment step, 310...Stop pressure setting after change step, 311...Stop pressure setting after change step, 312...Change The following steps are followed by a series of steps: 313...Stop pressure judgment step; 314...ECO flag deletion step; 401...Operation start; 402...Compressor control; 403...ECO mode judgment step; 404...Pressure switch type control cycle start step; 405...Pressure switch type control; 406...Thermal safety mode judgment step; 407...Ambient temperature anomaly judgment step; 408...Ambient temperature alarm judgment step; 409...Pressure switch type control cycle end step; 410...Operation end; 411...Abnormal flag setting step. 412... Alarm flag setting step, 413... ECO mode control cycle start step, 414... Thermal safety mode judgment step, 415... Ambient temperature anomaly judgment step, 416... Ambient temperature alarm judgment step, 417... Anomaly flag setting step, 418... Alarm flag setting step, 419... ECO mode control, 420... ECO mode control cycle end step, 421... AT45 mode judgment step, 422... AT45 mode control cycle start step, 423... AT45 mode control, 424... AT45 mode transition 425...AT45 mode control cycle end step, 426...AT40 mode judgment step, 427...AT40 mode control cycle start step, 428...AT40 mode control, 429...AT40 mode transfer judgment step, 430...AT45 mode judgment step, 431...AT40 mode control cycle end step, 432...ECO mode control judgment step, 1110...Pressure control unit, 1111...Cycle time judgment unit, 1112...Stop pressure change unit, 1113...ECO flag setting unit, C ST ...tolerance, C ST *T ECO ...the threshold for the second period, T OFF +T ON ...the cycle of pressure increase and decrease.

Claims

1. A compressor, characterized in that, include: Electric motor; The compressor body, driven by the electric motor, is capable of generating compressed gas; A container for storing the compressed gas generated by the compressor body; A pressure detector, used to detect the pressure of the compressed gas inside the container; and The control unit controls the electrical power supplied to the motor based on the detection result of the pressure detector; The control unit determines whether the pressure increase / decrease cycle from the pressure detector reaching the stop pressure to the start pressure and then back to the stop pressure exceeds a first cycle threshold. If the pressure increase / decrease cycle exceeds the first cycle threshold, the control unit reduces the stop pressure by a first pressure change value.

2. The compressor as described in claim 1, characterized in that: When the pressure increase / decrease cycle is lower than the first cycle threshold, the control unit increases the stop pressure by a second pressure change value.

3. The compressor as described in claim 1, characterized in that: The control unit divides the stop pressure into multiple modes and increases them to predetermined values ​​based on the ratio of the stop cycle time to the operation cycle time of the pressure increase / decrease cycle.

4. The compressor as described in claim 1, characterized in that: The control unit also functions as a frequency converter.

5. The compressor as described in claim 2, characterized in that: The control unit has a user setting unit that allows the user to set a first cycle threshold, a second cycle threshold, a first pressure change value, or a second pressure change value as parameters.

6. The compressor as described in claim 1, characterized in that: The control unit averages the time of multiple pressure increase / decrease cycles and uses the averaged value to determine whether the first cycle threshold is exceeded.

7. The compressor as described in claim 1 or 2, characterized in that: If the control unit determines that the stop pressure after reducing the first pressure change value is lower than the lower limit of the stop pressure, it will not change the setting of the stop pressure.

8. The compressor as described in claim 2, characterized in that: If the pressure increase / decrease cycle (T) OFF +T ON If the pressure is within a predetermined tolerance of the first cycle threshold, the control unit will not change the stop pressure P. MAX The settings.

9. A method for controlling a compressor, comprising storing the compressed gas generated by a compressor body driven by an electric motor in a container, detecting the pressure of the compressed gas in the container by a pressure detector, and controlling the electrical power supplied to the electric motor based on the detection result, the method for controlling the compressor being characterized in that: Determine whether the pressure increase / decrease cycle from the point where the pressure detector detects the stop pressure, decreases to the start pressure, and then reaches the stop pressure again exceeds a first cycle threshold. If the pressure increase / decrease cycle exceeds the first cycle threshold, reduce the stop pressure by the first pressure change value.

10. The compressor control method as described in claim 9, characterized in that: If the pressure increase / decrease cycle is lower than the first cycle threshold, the stop pressure is increased by a second pressure change value.

11. The compressor control method as described in claim 9, characterized in that: Based on the ratio of the stop cycle time to the operation cycle time of the pressure increase / decrease cycle, the stop pressure is divided into multiple modes and each mode is increased to a predetermined value.

12. The compressor control method as described in claim 10, characterized in that: Users can use the user settings section to set the first cycle threshold, the second cycle threshold, the first pressure change value, or the second pressure change value as parameters.

13. The compressor control method as described in claim 9, characterized in that: The time of multiple pressure increase / decrease cycles is averaged to determine whether it exceeds the first cycle threshold.

14. The compressor control method as described in claim 9 or 10, characterized in that: If the calculated stop pressure is lower than the lower limit of the stop pressure, the setting of the stop pressure is not changed.

15. The compressor control method as described in claim 10, characterized in that: If the pressure increase / decrease cycle (T) OFF +T ON If the stop pressure P is within the predetermined tolerance of the first cycle threshold, then the stop pressure P remains unchanged. MAX The settings.

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