Compressor and method for controlling the compressor

Abstract

This invention provides a compressor and a compressor control method that offer improved reliability in high ambient temperature environments. [Solution] In the normal operating mode, when the ambient temperature exceeds the first temperature threshold, or when the difference between the ambient temperature and the discharge area temperature reaches the temperature difference threshold T for HS mode DTH In any case where the pressure exceeds a certain level, the operation of the electric motor 104 is controlled based on either a heat safety mode, which lowers the set pressure that defines the operation of the electric motor 104 in accordance with the pressure in the compressed air storage tank 107, or the following:

Description

[Technical Field]

[0001] The present invention relates to a compressor and a method for controlling a compressor. [Background technology]

[0002] Gas compressors are known for producing compressed gas that is used as a power source in manufacturing lines, as well as an air source for machine tools, presses, and air blowers.

[0003] Furthermore, there are packaged gas compressors that achieve space savings by integrating the compressor body, the motor that drives it, the control circuit, the operation panel, and other components into a single package.

[0004] In these gas compressors, the reliability and durability of the compressor decrease as the ambient temperature rises. Therefore, one solution to ensure a continuous supply of compressed gas is to reduce the load on the gas compressor.

[0005] Patent Document 1 serves as background technology for this invention.

[0006] Patent Document 1 describes a compressor control method that prevents an emergency stop and allows operation to continue by reducing the rotation speed of the drive motor or the compression pressure when any of the sensor-detected values ​​of the discharge air temperature, differential pressure, coil temperature, or current reach a preset upper limit.

[0007] Patent Document 1 describes an operating method for a screw compressor, in which the compressed air temperature detected by an air temperature detection sensor, the first and second pressures detected by first and second pressure detection sensors, the coil temperature detected by a coil temperature detection sensor, and the drive motor current detected by a current detection sensor are input to a controller to determine the differential pressure between the first and second pressures, and when any of these compressed air temperature, differential pressure, coil temperature, or current reaches a predetermined upper limit, the controller switches to an operating load reduction mode, which reduces the operating load of the screw compressor.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] However, since the filing of Patent Document 1, further improvement in reliability has been demanded so that it can operate without problems even in a higher temperature environment.

[0010] The present invention provides a compressor and a method for controlling the compressor with improved reliability in operation under a high ambient temperature environment.

Means for Solving the Problems

[0011] The present invention includes a plurality of means for solving the above problems. For example, it includes an electric motor, a compressor main body having a compressor mechanism driven by the electric motor and discharging compressed air, an ambient temperature sensor for measuring the ambient temperature of the compressor, a discharge temperature sensor for measuring the temperature of the discharge portion region where the compressed air is discharged, and a control unit for controlling the operation of the electric motor based on the pressure in a tank for storing the compressed air and a set pressure. The control unit controls the operation of the electric motor based on either a normal operation mode or a heat safety mode in which the set pressure is decreased when the ambient temperature exceeds a first temperature threshold or when the difference between the ambient temperature and the temperature of the discharge portion region exceeds a second temperature threshold. [[ID=Y]]

Effects of the Invention

[0012] [[ID=Z]] According to the present invention, the reliability of operation in a high ambient temperature environment can be further improved. Problems, configurations, and effects other than those described above will be clarified by the description of the following embodiments.

Brief Description of the Drawings

[0013] [Figure 1] A perspective view showing the external appearance of a compressor in Embodiment 1 to which the present invention is applied. [Figure 2] A perspective view showing the internal configuration of a compressor in Embodiment 1 to which the present invention is applied. [Figure 3] This figure shows the conceptual configuration of a compressor in Embodiment 1 to which the present invention is applied. [Figure 4] A diagram showing the functional block of the control board in a compressor in Embodiment 1 to which the present invention is applied. [Figure 5] A diagram illustrating the overview of the operation of the heat safety mode installed in the compressor in Embodiment 1 to which the present invention is applied. [Figure 6] A diagram showing the operating state flow of a compressor in Embodiment 1 to which the present invention is applied. [Figure 7] A perspective view showing the internal configuration of a compressor in Embodiment 3 to which the present invention is applied. [Figure 8] This figure shows an example of a second temperature threshold for the lower limit setting pressure for each unit in a compressor in Embodiment 3 to which the present invention is applied. [Modes for carrying out the invention]

[0014] Embodiments of the compressor and compressor control method of the present invention will be described below with reference to the drawings. In the drawings used herein, the same or corresponding components are denoted by the same or similar reference numerals, and repeated descriptions of these components may be omitted.

[0015] In the following embodiments 1 to 6, a packaged compressor is described as an example in which a scroll compressor, which compresses air by orbiting motion by forming a compression chamber between a fixed scroll and an orbiting scroll, is housed in a casing as the compression method of the compressor body. However, the compressor of the present invention is not limited to the packaged type. Similarly, it is not limited to scroll compressors and can be applied to other compressors such as reciprocating compressors, screw compressors, and turbo compressors. Furthermore, the working fluid is not limited to air and can be applied to other gases as well.

[0016] <Embodiment 1> Embodiment 1 of the compressor and compressor control method of the present invention will be described with reference to Figures 1 to 6.

[0017] First, the overall configuration of the compressor will be explained using Figures 1 to 3. Figure 1 is a perspective view showing the external appearance of the compressor 100 in Embodiment 1, Figure 2 is a perspective view showing the internal configuration of the compressor 100 in Embodiment 1, and Figure 3 is a diagram showing the conceptual configuration of the entire compressor related to Embodiment 1.

[0018] The compressor 100 shown in Figures 1 and 2 is a single-stage compressor consisting of a compressor body 103 and an electric motor 104. The front panel, which forms part of the housing, is detachable from the rest of the housing by a retaining mechanism such as screws. An operating unit 117 for the user to operate the compressor 100 is provided on the front side.

[0019] As shown in Figure 3, the compressor 100 includes a filter 102, a compressor body 103, an electric motor 104, a check valve 105, an aftercooler 106, a tank 107, a dryer 108, a switch 110, a control board 111 that controls the operation of the electric motor 104 based on the pressure in the tank 107 that stores compressed air and a set pressure, a pressure sensor 112, a magnetic switch 113, a body temperature sensor 114, an ambient temperature sensor 115, and the like.

[0020] In the compressor 100, as shown in Figure 3, the air 101 supplied from the outside to the inside of the compressor 100 passes through the filter 102 and is supplied to the compressor body 103.

[0021] The electric motor 104 and the compressor body 103 are connected by a belt, which transmits power from the electric motor 104 to the compressor body 103, driving the compressor body 103. The compressed air in the compressor body 103 passes through the check valve 105 and the aftercooler 106, is temporarily stored in the tank 107, and is supplied to the outside as compressed air 109 through the dryer 108.

[0022] In the compressor 100, the entire compressor is operated and stopped by a switch 110 on the control unit 117, and the operation of each component of the compressor is controlled by the control board 111.

[0023] Furthermore, the control board 111 sends a command to the magnetic switch 113 in response to the pressure inside the tank 107 detected by the pressure sensor 112, thereby controlling the intermittent operation of the compressor body 103.

[0024] Furthermore, the compressor 100 of this embodiment is equipped with a main body temperature sensor 114 that measures the side temperature of the compressor body 103 as the temperature of the discharge area where compressed air is discharged, and an ambient temperature sensor 115 that measures the temperature of the air near the intake port 118 as the ambient temperature of the compressor 100.

[0025] Furthermore, the system controls the system to issue an alarm or malfunction alert if the ambient temperature of the compressor 100, as measured by the ambient temperature sensor 115, is outside the specified range of the compressor 100. In addition, if the temperature difference between the ambient temperature and the temperature of the compressor body 103, as measured by the main unit temperature sensor 114, exceeds a predetermined threshold, the system controls the system to issue an alarm or malfunction alert to prevent failure of the compressor body 103.

[0026] The temperature measured by the main unit temperature sensor 114 is approximately 100°C while the compressor 100 is in operation, as the temperature of the air discharged from the compressor body 103 is approximately 200°C. On the other hand, the temperature measured by the ambient temperature sensor 115 is the temperature of the area where the compressor 100 is operating, since it is located near the intake port 118 of the housing, for example, room temperature (for example, within the range of 0°C to 40°C).

[0027] Furthermore, the discharge temperature measured by the main unit temperature sensor 114 is not limited to the side temperature of the compressor body 103, but can also be configured to measure the temperature of the components between the compressor body 103 and immediately before the aftercooler 106, or the temperature of the compressed air itself in that section.

[0028] Similarly, the ambient temperature measured by the ambient temperature sensor 115 is not limited to the temperature of the air near the intake port 118. It is also possible to directly measure the temperature outside the housing near the intake port 118 or to measure the ambient temperature inside the housing other than the intake port 118.

[0029] Figure 4 is a functional block diagram of the control board 111 in this embodiment 1, and Figure 5 is a diagram showing an overview of the operation of the heat safety mode (sometimes referred to as "HS mode") installed in the compressor of embodiment 1.

[0030] As shown in Figure 4, the control board 111 has the following functional configuration: a pressure control unit 201, an ambient temperature determination unit 202, a pressure setting determination unit 203, a pressure setting change unit 204, a temperature difference determination unit 205, and a recording unit 206.

[0031] The pressure control unit 201 processes the sensor inputs from the pressure sensor 112, the main unit temperature sensor 114, and the ambient temperature sensor 115, and issues an opening and closing command for the magnetic switch 113.

[0032] The pressure control unit 201 determines the difference between the ambient temperature and the temperature of the compressor body 103, which is the discharge area, using the temperature difference determination unit 205, based on the ambient temperature and pressure setting determined by the ambient temperature determination unit 202 and the pressure setting determination unit 203, and, if necessary, the pressure setting changed by the pressure setting change unit 204, and executes the operating state flow of the compressor 100 shown in Figure 6.

[0033] Specifically, the pressure control unit 201 of the control board 111 operates in a normal mode and when the ambient temperature exceeds the first temperature threshold, or when the difference between the ambient temperature and the discharge area temperature exceeds the temperature difference threshold T for HS mode. DTH In any case where the pressure exceeds a certain level, the operation of the electric motor 104 is controlled based on either a heat safety mode that reduces the set pressure or another mode.

[0034] Here, the setting pressure to be changed can be one or more of the following: an operation stop pressure (upper limit pressure) which serves as the criterion for stopping the operation when the pressure in tank 107 exceeds a certain predetermined pressure, and an operation recovery pressure (lower limit pressure) which serves as the criterion for restarting the operation when the pressure in tank 107 falls below a certain predetermined pressure. In this embodiment, the case in which only the lower limit pressure is changed will be explained as an example.

[0035] The normal operating mode is activated when the ambient temperature exceeds the first temperature threshold, or when the difference between the ambient temperature and the discharge area temperature reaches the normal mode temperature difference threshold T. DT In any case where the temperature exceeds a certain level, this mode stops the operation of the compressor unit 103 by issuing a warning that the motor 104 has stopped due to abnormal shutdown caused by high temperature.

[0036] On the other hand, the heat safety mode is activated when the ambient temperature exceeds the first temperature threshold, or when the difference between the ambient temperature and the discharge area temperature reaches the HS mode temperature difference threshold T. DTH In any case where the temperature exceeds a certain level, the operation of the motor 104 is stopped, thereby stopping the operation of the compressor body 103. This is the same as in normal operation mode.

[0037] The difference between Heat Safety Mode and HS Mode is that the ambient temperature is below the temperature difference threshold T for HS Mode. DTH If the temperature exceeds a certain threshold, the set pressure (lower limit pressure in this embodiment) is lowered by a predetermined value to delay the return of operation of the electric motor 104, thereby preventing the temperature of the compressor body 103 from rising easily. Furthermore, once the ambient temperature no longer exceeds the temperature threshold, the set pressure is returned to its original value.

[0038] Furthermore, since the user's equipment connected downstream of the compressor 100 requires a specific air pressure, it is desirable to set a lower limit on the setting of the lower pressure to ensure that the pressure does not fall below that required level.

[0039] Temperature difference threshold T for HS mode according to set pressure DTHThis data is recorded as table data in the recording unit 206 within the control board 111, as shown in Figure 8 (Embodiment 3), which will be described later.

[0040] As a heat safety mode, for example, as shown in Figure 5, two modes can be set: a first heat safety mode that lowers the set pressure and changes the temperature threshold when the ambient temperature is 45°C or higher but less than 47°C, and a second heat safety mode that lowers the pressure and changes the temperature threshold when the ambient temperature is 47°C or higher but less than 50°C, and immediately stops operation when it is determined that the ambient temperature is 50°C or higher.

[0041] Furthermore, in the heat safety mode of this embodiment, when the control board 111 is driving the compressor body 103 in heat safety mode, it lowers the control pressure and, in parallel with that, sets the temperature difference threshold T for HS mode according to the set pressure. DTH The temperature difference threshold T for HS mode will be lowered. This is because, in heat safety mode, the temperature of the compressor body 103 does not rise easily, making it difficult to detect whether the compressor is under high-temperature load. Therefore, in order to avoid operation under conditions where it should not be operated when the outside temperature is high, the temperature difference threshold T for HS mode will be lowered to detect faults with greater accuracy. DTH The configuration is designed to lower [the value].

[0042] The user can freely select between normal operation mode and heat safety mode using the control unit 117, and the user's selection is stored in the recording unit 206 of the control board 111.

[0043] Next, the control flow of the compressor 100 in this embodiment will be explained using Figure 6. Figure 6 is a conceptual diagram showing the operation flow of the compressor of Embodiment 1. In Figure 6, the main operating components of each step are the various parts within the control board 111, but in the following explanation, it will be described as the control board 111.

[0044] As shown in FIG. 6, first, after the control board 111 starts the flow (S301) and starts the operation of the compressor 100 (S302), it determines whether the heat safety mode is effective (S303). When it is determined to be effective, the process proceeds to step S308. On the other hand, when it is determined not to be effective, the process proceeds to step S304 and transitions to normal mode control.

[0045] In normal mode control, the control board 111 calculates the temperature difference T between the ambient temperature measured by the ambient temperature sensor 115 and the discharge area temperature measured by the body temperature sensor 114 D and determines whether it is greater than the temperature difference threshold value T DT for the normal mode (S305).

[0046] In step S305, when the temperature difference T D between the ambient temperature and the discharge area temperature is determined to be greater than the temperature difference threshold value T DT for the normal mode, the control board 111 assigns a compressor body abnormality flag (S331), reports an alarm and an abnormality, and then ends the flow (S307).

[0047] On the other hand, when the temperature difference T D is determined to be less than or equal to the temperature difference threshold value T DT for the normal mode, the control board 111 loops the normal control mode (S306).

[0048] When it is determined to be effective in the determination of the effectiveness of the heat safety mode (S303), the control board 111 transitions to heat safety mode control (S308).

[0049] In heat safety mode control, first, the control board 111 determines whether the ambient temperature AT is 45° C. or higher (S309).

[0050] When it is determined that the ambient temperature AT is less than 45°C, the process proceeds to step S310, and the control board 111 determines whether or not the heat safety mode is disabled (S310). If the control board 111 determines that the heat safety mode is disabled, it transitions to normal mode control (S304), and if it determines that it is enabled, it continues to loop the heat safety mode control (S311).

[0051] In contrast, if it is determined in step S309 that the ambient temperature AT is 45°C or higher, the process proceeds to step S312, where the control board 111 then determines whether the ambient temperature AT is 47°C or higher (S312). If it is determined that the ambient temperature AT is 45°C or higher but less than 47°C, the process proceeds to step S313, where the control board 111 determines whether the lower limit pressure setting value Pu is 0.55 MPa or lower (S313).

[0052] If the control board 111 determines that the set value Pu for the lower limit pressure is less than 0.55 MPa, it leaves the set value Pu as is and proceeds to step S315A. If it determines that the set value Pu is 0.55 MPa or greater, it sets the lower limit pressure to 0.55 MPa (S314) and proceeds to step S315A.

[0053] Thus, it is desirable to set a minimum reference value for the lower limit pressure of the set pressure in heat safety mode. Furthermore, it is desirable that the control board 111 keeps the set value unchanged when the lower limit pressure is below the set value in heat safety mode, and only changes it when it exceeds the set value.

[0054] Subsequently, the control board 111 sets the temperature difference threshold T for HS mode, which is a value corresponding to the lower pressure limit. DTH The settings are configured (S315A), and the system transitions to the first heat safety mode control (S316).

[0055] In the first heat safety mode control, the control board 111 detects the temperature difference T between the ambient temperature measured by the ambient temperature sensor 115 and the discharge area temperature measured by the main unit temperature sensor 114.D The temperature difference threshold T for HS mode DTH Determine whether it is greater than or less than (S317).

[0056] In step S317, the temperature difference T between the ambient temperature and the discharge area temperature. D The temperature difference threshold T for HS mode DTH If it is determined to be larger, the control board 111 assigns a compressor body abnormality flag (S331) and terminates the flow (S307).

[0057] In contrast, the temperature difference T D The temperature difference threshold T for HS mode DTH If the following is determined, the control board 111 again determines whether the ambient temperature AT is less than 45°C (S318), and if it is determined to be less than 45°C, the process proceeds to step S333A, changing the lower limit pressure setting value Pu to the user-set pressure and the HS mode temperature difference threshold T DTH The temperature difference threshold T for normal mode DT The process is then raised to step S333A, and then the process proceeds to step S310.

[0058] Thus, even after the control board 111 changes the set pressure according to the ambient temperature, it also adjusts the set pressure and the temperature difference threshold T for HS mode according to the subsequent ambient temperature. DTH The temperature difference threshold T for normal mode DT It is desirable to raise it to that level.

[0059] In response to this, if it is determined that the temperature is 45°C or higher, the process proceeds to step S319, where the control board 111 determines whether the ambient temperature AT is less than 47°C (S319). If it is determined that the temperature is less than 47°C, the process proceeds to step S310A, where the control board 111 determines whether the heat safety mode is disabled (S310A).

[0060] If it is determined to be invalid, the process proceeds to step S333B, and the control board 111 changes the lower limit pressure setting value Pu to the user-set pressure and the temperature difference threshold T for HS mode. DTH The temperature difference threshold T for normal modeDT The temperature is raised (S333B), and then the process proceeds to step S304 to transition to normal mode control (S304). However, if it is determined to be valid in step S310A, the first heat safety mode control is continued in a loop (S321).

[0061] In contrast, if it is determined in step S319 that the ambient temperature is 47°C or higher, the process proceeds to step S320, where the control board 111 determines whether the ambient temperature AT is higher than 50°C (S320). If it is determined that the ambient temperature is higher than 50°C, it assigns an ambient temperature abnormality flag (S332), issues an alarm / abnormality, and then terminates the operation (S307).

[0062] In contrast, if it is determined that the temperature is below 50°C, the process returns to step S309 without continuing the first heat safety mode loop, and proceeds to the process of deciding which heat mode to use.

[0063] If it is determined in step S312 that the ambient temperature AT is 47°C or higher, the process proceeds to step S322, where the control board 111 determines whether the ambient temperature AT is 50°C or higher (S322). If the ambient temperature is 50°C or higher, an ambient temperature abnormality flag is added (S332), and the operation is terminated (S307).

[0064] In contrast, if the ambient temperature AT is determined to be between 47°C and 50°C, the process proceeds to step S323, where the control board 111 determines whether the lower limit pressure setting value Pu is 0.45 MPa or less (S323).

[0065] If the control board 111 determines that the set value Pu for the lower limit pressure is less than 0.45 MPa, it leaves the set value Pu as is and proceeds to step S315B. If it determines that the set value Pu is 0.45 MPa or greater, it sets the lower limit pressure to 0.45 MPa (S324) and proceeds to step S315B.

[0066] Subsequently, the control board 111 sets the temperature difference threshold T for HS mode, which is a value corresponding to the lower pressure limit. DTH The settings are configured (S315B), and the system transitions to the second heat safety mode control (S325).

[0067] Note that the temperature difference threshold T for HS mode is set in step S315A. DTH And the temperature difference threshold T for HS mode set in step S315B. DTH As mentioned above, this is a threshold value corresponding to the lower limit pressure; if the lower limit pressure is set to the same value, it will be the same value, and if the lower limit pressure is set to a different value, it will be a different value.

[0068] In the second heat safety mode control, the control board 111 detects the temperature difference T between the ambient temperature measured by the ambient temperature sensor 115 and the discharge area temperature measured by the main unit temperature sensor 114. D The temperature difference threshold T for HS mode DTH Determine whether it is greater than or less than (S326).

[0069] In step S326, the temperature difference T between the ambient temperature and the discharge area temperature is... D The temperature difference threshold T for HS mode DTH If it is determined to be larger, the control board 111 assigns a compressor body abnormality flag (S331) and terminates the flow (S307).

[0070] In contrast, the temperature difference T D The temperature difference threshold T for HS mode DTH If the following is determined, the control board 111 again determines whether the ambient temperature AT is less than 45°C (S327), and if it is determined to be less than 45°C, the process proceeds to step S333A, changing the lower limit pressure setting value Pu to the user-set pressure and the HS mode temperature difference threshold T DTH The temperature difference threshold T for normal mode DT The process is then raised to step S333A, and then the process proceeds to step S310.

[0071] In response to this, if it is determined that the temperature is 45°C or higher, the process proceeds to step S328, where the control board 111 determines whether the ambient temperature AT is less than 47°C (S328). If it is determined that the temperature is less than 47°C, the process returns to step S309 without continuing the second heat safety mode loop, and proceeds to the process of deciding which heat mode to loop in.

[0072] In response to this, if it is determined in step S328 that the ambient temperature is 47°C or higher, the process proceeds to step S329, where the control board 111 determines whether the ambient temperature AT is higher than 50°C (S329). If it is determined that the ambient temperature is higher than 50°C, it sets an ambient temperature abnormality flag (S332) and terminates the operation (S307).

[0073] If it is determined in step S329 that the temperature is 50°C or lower, the process proceeds to step S310B, where the control board 111 determines whether or not the heat safety mode is disabled (S310B).

[0074] If it is determined to be invalid, the process proceeds to step S333B, and the control board 111 changes the lower limit pressure setting value Pu to the user-set pressure and the temperature difference threshold T for HS mode. DTH The temperature difference threshold T for normal mode DT The temperature is raised (S333B), and then the process proceeds to step S304 to transition to normal mode control (S304). However, if it is determined to be valid in step S310B, the second heat safety mode control is continued in a loop (S330).

[0075] Next, the effects of this embodiment will be described.

[0076] The compressor 100 of Embodiment 1 of the present invention described above includes an electric motor 104, a compressor body 103 having a compressor mechanism driven by the electric motor 104 for discharging compressed air, an ambient temperature sensor 115 for measuring the ambient temperature of the compressor 100, a body temperature sensor 114 for measuring the temperature of the discharge area for discharging compressed air, and a control board 111 for controlling the operation of the electric motor 104 based on the pressure in the tank 107 for storing compressed air and a set pressure. The control board 111 has a normal operating mode and a temperature difference threshold T for HS mode when the ambient temperature exceeds a first temperature threshold or when the difference between the ambient temperature and the discharge area temperature is exceeded. DTH In any case where the pressure exceeds a certain level, the operation of the electric motor 104 is controlled based on either a heat safety mode that reduces the set pressure or another mode.

[0077] In recent years, summer temperatures have risen significantly, and users are demanding compressors that can operate without interruption as much as possible, even at high temperatures. In response to this, by using a heat safety mode that lowers the set pressure when high temperatures occur, the amount of heat generated by the compressor is also suppressed as the set pressure decreases, allowing the temperature rise to rise more slowly and enabling continued operation, thereby further improving the reliability of operation in high ambient temperature environments.

[0078] Furthermore, when the compressor body 103 is driven in heat safety mode, the control board 111 sets a temperature difference threshold T for HS mode according to the set pressure. DTH This reduces the heat. In the aforementioned heat safety mode, the compressor operates while suppressing heat generation. Therefore, even at temperatures that would normally cause a high-temperature abnormality and require shutdown in normal operation mode, the compressor may continue operating in heat safety mode. In the control system that detects compressor wear by taking the difference between the discharge air temperature and the ambient temperature, the threshold for detecting wear is changed according to the compressor's set pressure value when the set pressure is reduced. This makes it easier for the compressor to stop when the pressure is reduced, allowing for more appropriate protection of the compressor at high temperatures and ensuring higher reliability even in high ambient temperature environments than conventional compressors.

[0079] Furthermore, even after the control board 111 changes the set pressure according to the ambient temperature, it also adjusts the set pressure and the temperature difference threshold T for HS mode according to the subsequent ambient temperature. DTH The temperature difference threshold T for normal mode DT By raising the temperature, it becomes possible to return the system from a reduced operating state (when operating in heat safety mode is no longer necessary) back to a normal operating state, thereby achieving stable operation.

[0080] Furthermore, by setting a minimum reference pressure for the lower limit of the set pressure in heat safety mode, the minimum necessary pressure is ensured, thereby minimizing the interruption of the compressed air supply and minimizing the risk of the machine or other equipment using compressed air shutting down.

[0081] Furthermore, the control board 111 can also operate according to user settings by keeping the set pressure (upper and lower pressure limits) as is if it is below the set value in heat safety mode, and changing it if it exceeds the set value.

[0082] <Embodiment 2> A compressor and a compressor control method according to Embodiment 2 of the present invention will be described.

[0083] In the compressor 100 of Embodiment 1 described above, only the lower limit pressure, which is the criterion for restarting when the pressure in the tank 107 falls below a predetermined pressure, was changed in the heat safety mode, which lowers the set pressure that defines the operation of the electric motor 104 according to the pressure in the tank 107 that stores compressed air. However, in the compressor of this embodiment, the upper limit pressure, which is the criterion for stopping when the pressure in the tank 107 rises above a predetermined pressure, is changed simultaneously with the lower limit pressure.

[0084] Note that when changing both the upper and lower pressure limits, it is not necessary to change them simultaneously. It is also possible to change only the upper pressure limit while leaving the lower pressure limit unchanged.

[0085] The other configurations and operations are substantially the same as those of the compressor and compressor control method in Embodiment 1 described above, and details are omitted.

[0086] In the compressor and compressor control method of Embodiment 2 of the present invention, substantially the same effects as those of the compressor and compressor control method of Embodiment 1 described above can be obtained.

[0087] Furthermore, by changing the upper pressure limit, it becomes possible to more reliably protect the compressor at high temperatures.

[0088] <Embodiment 3> A compressor and a compressor control method according to Embodiment 3 of the present invention will be described with reference to Figures 7 and 8. Figure 7 is a perspective view showing the internal configuration of the compressor of Embodiment 3, and Figure 8 is a diagram showing an example of a second temperature threshold relative to the lower limit set pressure for each unit in the compressor of Embodiment 3.

[0089] The compressor 100A of this embodiment shown in Figure 7 has multiple compressor bodies 103A, 103B, and 103C. In such a compressor 100A, the control board 111A controls the temperature difference threshold T for HS mode. DTH These are managed independently for each compressor unit, 103A, 103B, and 103C.

[0090] Specifically, the main unit temperature sensor 114A is independently provided on the compressor body 103A, the main unit temperature sensor 114B on the compressor body 103B, and the main unit temperature sensor 114C on the compressor body 103C, and accordingly, the temperature difference threshold T for HS mode is set accordingly. DTH We have decided to manage it independently.

[0091] As shown in Figure 8, the temperature difference threshold T for HS mode depends on the lower limit set pressure. DTH Although it is changed, the compressor body 103C, which is located at the lowest vertical position, has a lower limit setting pressure that is lower than the compressor body 103B, which is located in the vertical center directly above it, at all lower limit setting pressures, compared to the HS mode temperature difference threshold T DTHThe temperature difference threshold T for HS mode is set 10°C lower, and compared to the compressor body 103A located furthest upward in the vertical direction, the temperature difference threshold T for HS mode is set lower at all lower limit pressure settings. DTH The temperature is set 5℃ lower.

[0092] The other configurations and operations are substantially the same as those of the compressor and compressor control method described in Embodiment 1 or Embodiment 2 above, and details are omitted.

[0093] Furthermore, the compressor 100A of this embodiment is not limited to the configuration in which only the lower limit pressure is changed, as in the compressor 100 of Embodiment 1. It may also be configured to change both the upper limit pressure and the lower limit pressure, as in Embodiment 2, or even to change only the upper limit pressure.

[0094] In the compressor and compressor control method of Embodiment 3 of the present invention, substantially the same effects as those of the compressor and compressor control method of Embodiment 1 or Embodiment 2 described above can be obtained.

[0095] Furthermore, if there are multiple compressor units 103A, 103B, and 103C, the control board 111A has a temperature difference threshold T for HS mode. DTH By independently managing each compressor unit 103A, 103B, and 103C, it is possible to accommodate situations where the cooling efficiency differs depending on the placement of multiple compressor units.

[0096] <Embodiment 4> A compressor and a compressor control method according to Embodiment 4 of the present invention will be described.

[0097] The compressor of this embodiment, like the compressor 100 of Embodiment 1, records a temperature difference threshold T for HS mode in the recording unit 206 within the control board 111. DTH The temperature difference threshold T for HS mode relative to the set pressure is not recorded as table data according to the set pressure in the recording unit 206. DTH This is a format in which a function with a variable is recorded.

[0098] The other configurations and operations are substantially the same as those of the compressor and compressor control method in any of the embodiments 1 to 3 described above, and details are omitted.

[0099] Furthermore, the function-based approach used in this embodiment is also effective in configurations where both the lower and upper pressure limits are changed, such as in Embodiment 2; configurations where only the upper pressure limit is changed; and even in multi-stage compressors 100A, such as in Embodiment 3. In particular, when used in a multi-stage compressor 100A as in Embodiment 3, different functions can be used for each compressor body 103A, 103B, and 103C. It is also possible to use a table for some stages and a function for others. Moreover, even when a multi-stage compressor 100A like Embodiment 3 changes both the upper and lower pressure limits as in Embodiment 2, different functions can be used for each compressor body 103A, 103B, and 103C, and it is also possible to use a table for some stages and a function for others.

[0100] In the compressor and compressor control method of Embodiment 4 of the present invention, substantially the same effects as those of the compressor and compressor control method of any of the embodiments 1 to 3 described above can be obtained.

[0101] <Embodiment 5> A compressor and a compressor control method according to Embodiment 5 of the present invention will be described.

[0102] In the compressor of this embodiment, when the compressor body 103 is driven in heat safety mode, as in any of the compressors of Embodiments 1 to 4, the temperature difference threshold T for HS mode is set according to the set pressure (lower limit pressure). DTH Instead of lowering it, when the compressor body 103 is driven in heat safety mode, the temperature difference threshold T for HS mode is set by referring to other pressure values, such as the average of the lower and upper pressure limits or the average pressure during compressor operation. DTH This configuration sets the temperature difference threshold T for HS mode according to the average value of the pressure in tank 107 over a certain period in the past. DTH It is possible to create a form that lowers the level.

[0103] The other configurations and operations are substantially the same as those of the compressor and compressor control method described in Embodiments 1 to 4 above, and details are omitted.

[0104] Furthermore, it is possible to use it in conjunction with any of the compressors of Embodiments 1 to 4.

[0105] In the compressor and compressor control method of Embodiment 5 of the present invention, substantially the same effects as those of the compressor and compressor control method of Embodiments 1 to 4 described above can be obtained.

[0106] <Embodiment 6> A compressor and a compressor control method according to Embodiment 6 of the present invention will be described.

[0107] The compressor of this embodiment is a configuration in which, in any of the compressors of Embodiments 1 to 5, operation control by an inverter is employed instead of the magnetic switch 113. In this embodiment, the temperature difference threshold T for HS mode DTH The reference settings for lowering the pressure can refer not only to the set pressure but also to the relationship between the set pressure and the rotational speed, etc.

[0108] The other configurations and operations are substantially the same as those of the compressor and compressor control method in any of the embodiments 1 to 5 described above, and details are omitted.

[0109] In the compressor and compressor control method of Embodiment 6 of the present invention, substantially the same effects as those of the compressor and compressor control method of any of the embodiments 1 to 5 described above can be obtained.

[0110] <Other> The embodiments described above are merely illustrative examples to aid in understanding the concept of the present invention and are not intended to limit the scope of the invention. The embodiments may include additions, deletions, or substitutions of various components without departing from the spirit of the invention.

[0111] For example, the various functional units described in each of the above embodiments may be realized using circuits. The circuits may be dedicated circuits that realize a specific function, or they may be general-purpose circuits such as processors.

[0112] Furthermore, at least a portion of the processing in each of the above embodiments can also be implemented using a general-purpose computer as the basic hardware. The program that implements the above processing may be provided stored on a computer-readable recording medium. The program is stored on the recording medium as an installable file or an executable file. The recording medium may be a magnetic disk, an optical disk (CD-ROM, CD-R, DVD, etc.), a magneto-optical disk (MO, etc.), or a semiconductor memory. Any recording medium that can store a program and is readable by a computer may be used. Alternatively, the program that implements the above processing may be stored on a computer (server) connected to a network such as the Internet, and downloaded to a computer (client) via the network. [Explanation of symbols]

[0113] 100, 100A... Compressor 101...Air 102, 102A, 102B, 102C… filters 103, 103A, 103B, 103C... Compressor body 104,104A,104B,104C…Electric motor 105, 105A, 105B, 105C... Check valves 106, 106A, 106B, 106C, 106D… Aftercooler 107... Tank 108... Hair dryer 109... Compressed air 110... Switch 111,111A... Control board (control unit) 112... Pressure sensor 113, 113A, 113B, 113C… Magnetic switches 114, 114A, 114B, 114C... Main unit temperature sensor (discharge temperature sensor) 115... Ambient temperature sensor 117...Operation unit 118... Air intake 201... Pressure Control Unit 202... Ambient temperature determination unit 203... Pressure setting determination unit 204... Pressure setting change section 205...Temperature difference determination section 206... Records Department AT…Ambient temperature T DT ...Temperature difference threshold for normal mode T DTH ...Temperature difference threshold for HS mode (second temperature threshold)

Claims

1. Electric motor and, A compressor body having a compressor mechanism that is driven by the aforementioned electric motor and discharges compressed air, An ambient temperature sensor that measures the ambient temperature around the compressor, A discharge temperature sensor for measuring the temperature of the discharge area where the compressed air is discharged, The system includes a control unit that controls the operation of the electric motor based on the pressure in a tank for storing compressed air and a set pressure, The control unit controls the operation of the electric motor based on either a normal operating mode or a heat safety mode in which the set pressure is reduced when the ambient temperature exceeds a first temperature threshold or when the difference between the ambient temperature and the discharge area temperature exceeds a second temperature threshold. Compressor.

2. In the compressor according to claim 1, When the control unit is operating the compressor body in the heat safety mode, it lowers the second temperature threshold according to the set pressure. Compressor.

3. In the compressor according to claim 2, After the control unit changes the set pressure according to the ambient temperature, it will raise the set pressure and the second temperature threshold according to the subsequent ambient temperature. Compressor.

4. In the compressor according to claim 1, A minimum reference value is set for the lower limit pressure of the set pressure in the heat safety mode. Compressor.

5. In the compressor according to claim 1, The control unit shall keep the set pressure as is if it is less than or equal to the set value in the heat safety mode, and change it if it exceeds the set value. Compressor.

6. In the compressor according to claim 1, If there are multiple compressor bodies, the control unit manages the second temperature threshold independently for each compressor body. Compressor.

7. A control method for a compressor comprising: an electric motor; a compressor body having a compressor mechanism driven by the electric motor and discharging compressed air; an ambient temperature sensor for measuring the ambient temperature of the compressor; and a discharge temperature sensor for measuring the temperature of the discharge region where the compressed air is discharged, The operation of the electric motor is controlled based on either a normal operating mode or a heat safety mode in which the set pressure is reduced when the ambient temperature exceeds a first temperature threshold or when the difference between the ambient temperature and the discharge area temperature exceeds a second temperature threshold. A method for controlling a compressor.

8. In the compressor control method according to claim 7, When the compressor body is driven in the heat safety mode, the second temperature threshold is lowered according to the set pressure. A method for controlling a compressor.

9. In the compressor control method according to claim 8, Even after changing the set pressure according to the ambient temperature, the set pressure and the second temperature threshold are raised according to the subsequent ambient temperature. A method for controlling a compressor.

10. In the compressor control method according to claim 7, A minimum reference value is set for the lower limit pressure of the set pressure in the heat safety mode. A method for controlling a compressor.

11. In the compressor control method according to claim 7, If the set pressure is less than or equal to the set value in the heat safety mode, the set value will remain unchanged; if it exceeds the set value, it will be changed. A method for controlling a compressor.

12. In the compressor control method according to claim 7, If there are multiple compressor units, the second temperature threshold is managed independently for each compressor unit. A method for controlling a compressor.

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