Gas compressor, gas compressor monitoring device, and gas compressor monitoring method

Abstract

To provide a gas compressor capable of estimating effects obtained by upgrading a gas compressor more accurately than before without decomposing the gas compressor, a monitoring device for a gas compressor, and a monitoring method for a gas compressor.SOLUTION: A gas compressor calculates an amount of cooling heat of an air cooler 5 based on a state amount of compressed air detected by a state amount detection unit; calculates an operating condition of the air cooler 5 when replacing a compression mechanism unit 3 from the amount of cooling heat; calculates an operating cost when replacing the compression mechanism unit 3 based on the operating condition; calculates a replacement cost and energy saving effect when replacing the compression mechanism unit 3 based on the operating cost; and displays the calculation results of the replacement cost and energy saving effect on a display device 19.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gas compressor, a gas compressor monitoring device, and a gas compressor monitoring method. [Background technology]

[0002] Patent Document 1 describes a monitoring device and monitoring method for an air compressor. Patent Document 1 states, "For each consumable part, a power loss rate equivalent to the ratio of current power consumption to the power consumption when the part is at a 'normal' level of deterioration, i.e., when the part is new, is calculated. This power loss rate indicates the magnitude of power loss, and can be estimated as the energy-saving effect of eliminating wasted power consumption by replacing the part." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6797528 Summary of the Invention [Problem to be solved by the invention]

[0004] In the technology described in Patent Document 1, the effect of reducing power consumption by replacing a part is calculated based on the ratio of the current power consumption to the power consumption when the part was new.

[0005] 2. Description of the Related Art An air compressor, which is a type of gas compressor, includes a compression mechanism that compresses air and an air cooler that cools the compressed, high-temperature air to a predetermined temperature.

[0006] As described in Patent Document 1, if replacement of consumable parts is encouraged and as a result only the consumable parts are replaced, there is a problem that the amount of compressed air in the compression mechanism increases, and the cooling capacity required of the air cooler also increases accordingly.

[0007] However, like consumables, air coolers can experience a decline in cooling performance during use due to dust clogging between the fins of the heat exchanger, deformation of the fins, or dirt inside the fins or compressed air flow path, etc. Therefore, there is a possibility that the quality standards for the temperature of compressed air supplied to external compressed air consumers may not be met.

[0008] In addition, it became clear that there is a concern that when consumable parts and compression mechanisms, which have a large impact on the power consumption of an air compressor, are replaced with parts with higher performance than new ones, it is impossible to determine whether the cooling capacity of the installed air cooler is sufficient to meet the quality standards for the supply temperature of compressed air due to deterioration of the air cooler over time.

[0009] In other words, even if parts were replaced, it was unclear whether the expected effect would be achieved, and it became clear that there was room for improvement.

[0010] The present invention provides a gas compressor, a gas compressor monitoring device, and a gas compressor monitoring method that make it possible to estimate the effects obtained by upgrading a gas compressor with higher accuracy than conventional methods without disassembling the gas compressor. [Means for solving the problem]

[0011] The present invention includes a plurality of means for solving the above-mentioned problems, and one example thereof is a gas compressor that compresses gas, comprising: a motor; a compression mechanism that compresses gas by rotation of the motor; a gas cooler that cools the compressed gas compressed by the compression mechanism; a state quantity detection unit that detects state quantities related to the operation of the gas compressor; and a monitoring unit that monitors the state of the gas compressor, wherein the monitoring unit calculates a cooling heat quantity of the gas cooler based on the state quantities of the compressed gas detected by the state quantity detection unit, calculates operating conditions of the gas cooler when the compression mechanism is replaced from the cooling heat quantity, calculates operating costs when the compression mechanism is replaced based on the operating conditions, calculates replacement costs and energy-saving effects when the compression mechanism is replaced based on the operating costs, and displays the calculated replacement costs and energy-saving effects on a display unit. [Effects of the Invention]

[0012] According to the present invention, the effects obtained by upgrading a gas compressor can be estimated with higher accuracy than in the past without disassembling the gas compressor. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a configuration diagram of an air compressor according to a first embodiment of the present invention. [Figure 2] 1 is a configuration diagram of a monitoring device according to a first embodiment of the present invention. [Figure 3] FIG. 2 is a configuration diagram of a calculation unit in a monitoring device according to a first embodiment of the present invention. [Figure 4] 4 shows the relationship between the amount of discharged air and the rotation speed of the compression mechanism in the first embodiment of the present invention. [Figure 5] 4 shows the relationship between the amount of discharged air and the rotation speed of the compressed air cooling fan in the first embodiment of the present invention. [Figure 6] 1 shows the relationship between the rotation speed and discharge air volume of the compressed air cooling fan after aging in the first embodiment of the present invention. [Figure 7]4 shows the relationship between the rotation speed of the compressed air cooling fan and the amount of heat cooled by the air cooler in the first embodiment of the present invention. [Figure 8] FIG. 4 is a configuration diagram of an air compressor according to a second embodiment of the present invention. [Figure 9] FIG. 10 is a configuration diagram of a monitoring device according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a configuration diagram of a calculation unit related to a liquid cooling machine according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the gas compressor, the gas compressor monitoring device, and the gas compressor monitoring method of the present invention will be described with reference to the drawings. In the drawings used in this specification, identical or similar reference numerals are used to designate identical or corresponding components, and repeated description of these components may be omitted.

[0015] In the following embodiments, an air compressor that compresses air as a gas to a predetermined pressure will be described, but the gas is not limited to air.

[0016] <First Example> A first embodiment of a gas compressor, a gas compressor monitoring device, and a gas compressor monitoring method according to the present invention will be described with reference to FIGS. 1 to 7. FIG.

[0017] First, the overall configuration of the air compressor will be described with reference to Fig. 1. Fig. 1 shows the configuration of the air compressor in this embodiment.

[0018] The air compressor 1 shown in Figure 1 is a machine that compresses air, and is composed of an intake filter 2, a motor 4 that drives the rotation of a compression mechanism 3 that compresses air by the rotation of the motor 4, an air cooler 5 that cools the high-temperature compressed air compressed by the compression mechanism 3, an air cooling fan 6 that blows cooling air to the air cooler 5, a discharge filter 7, and compressed air piping 8 that connects these.

[0019] The compression mechanism 3 , which is driven to rotate by the motor 4 , compresses the air drawn in from the outside through the suction filter 2 to a predetermined pressure, and then discharges the compressed air into the compressed air pipe 8 .

[0020] Here, the compressed air in the compressed air pipe 8 is at a temperature significantly higher than room temperature, so it is cooled to a predetermined temperature in the air cooler 5 provided downstream of the compression mechanism part 3.

[0021] Thereafter, the compressed air is supplied to a compressed air consuming device (not shown) outside the air compressor 1 via a discharge filter 7.

[0022] The air compressor 1 is equipped with a plurality of sensors (state quantity detection units) that detect state quantities related to the operation of the air compressor 1, such as the temperature and pressure of the air before compression, the temperature and pressure of the compressed air before or after passing through the air cooler 5 after compression, and the rotational speed of the motor 4 that rotates and drives the compression mechanism unit 3.

[0023] A total of two pressure sensors are provided: a first pressure sensor 9 for measuring the pressure downstream of the suction filter 2, and a second pressure sensor 10 for measuring the pressure downstream of the compression mechanism section 3.

[0024] A total of two rotation speed detection means are provided: a first rotation speed detection unit 11 that detects the rotation speed of the motor 4 that rotates and drives the compression mechanism unit 3, and a second rotation speed detection unit 12 that detects the rotation speed of the air cooling fan 6. It is desirable that both the first rotation speed detection unit 11 and the second rotation speed detection unit 12 also have means for detecting the value of the current supplied to the motor 4 or the air cooling fan 6 in addition to the rotation speed.

[0025] A total of three temperature sensors are provided: a first temperature sensor 13 that detects the outside air temperature, a second temperature sensor 14 that detects the temperature of compressed air downstream of the compression mechanism 3, and a third temperature sensor 15 that detects the temperature of compressed air downstream of the air cooler 5.

[0026] The monitoring device 16 is a part that collects, calculates, and outputs status monitoring data from various sensors in order to monitor the status of the air compressor 1, and is a suitable entity that executes each step of the gas compressor monitoring method.

[0027] The configuration of the monitoring device 16 is shown in Fig. 2. The monitoring device 16 is composed of a data collection unit 17 that collects output values ​​from various sensors, a calculation unit 18 that calculates energy-saving performance and cost-reduction effects based on the collected data, and a display device 19 that outputs and displays the calculation results of the calculation unit 18 (energy-saving effects, cost-reduction effects obtained by replacing the compression mechanism unit 3).

[0028] The monitoring device 16 may be configured as hardware using a dedicated circuit board, or may be configured as software executed by a computer. If configured as hardware, it can be realized by integrating multiple arithmetic units that execute processing on a wiring board, or in a semiconductor chip or package. If configured as software, it can be realized by installing a high-speed general-purpose CPU in a computer and running a program that executes the desired arithmetic processing.

[0029] The data collection unit 17 is a part that collects information on pressure, rotational speed, and temperature, and is a part that accepts input of output values ​​from the above-mentioned first pressure sensor 9, second pressure sensor 10, first rotational speed detection unit 11, second rotational speed detection unit 12, first temperature sensor 13, second temperature sensor 14, and third temperature sensor 15, and is connected to each of these sensors by wire or wirelessly (not shown in the illustration for convenience).

[0030] The monitoring device 16 of this embodiment calculates the cooling heat quantity of the air cooler 5 based on the state quantity of the compressed air detected by the state quantity detection unit, calculates the operating conditions of the air cooler 5 when the compression mechanism unit 3 is replaced from the cooling heat quantity, calculates the operating cost when the compression mechanism unit 3 is replaced based on the operating conditions, calculates the replacement cost and energy saving effect when the compression mechanism unit 3 is replaced based on the operating cost, and displays the calculation results of the replacement cost and energy saving effect on the display device 19. Details will be described later.

[0031] In this embodiment, the monitoring device 16 can calculate the operating cost of the compression mechanism unit 3 before replacement based on the current value and rotation speed detected by the state quantity detection unit and the discharge rate of compressed air searched from the first database 20. Also, the monitoring device 16 can calculate the amount of cooled heat based on the temperature and pressure of the compressed air upstream of the air cooler 5 detected by the state quantity detection unit and the temperature of the compressed air downstream of the air cooler 5. Furthermore, the monitoring device 16 can calculate the operating cost of the compression mechanism unit 3 as a replacement candidate based on the discharge rate of the compression mechanism unit 3 before replacement and the discharge rate and rotation speed of the compression mechanism unit 3 as a replacement candidate, which are searched from the second database 22. This will be described in detail later.

[0032] FIG. 3 shows the configuration of the calculation unit 18.

[0033] As shown in FIG. 3, the calculation unit 18 includes an air calculation unit 40, a first database 20 storing information on the performance of the currently installed compression mechanism unit 3 such as information on the rotation speed of the motor 4 and the discharge amount of compressed air, a second database 22 storing information on the performance and cost of the replacement candidate compression mechanism unit 3 such as information on the rotation speed and discharge amount of compressed air of the replacement candidate compression mechanism unit 3, and a third database 23 storing information on the performance and cost of the replacement candidate air cooler 5 such as information on the cooling performance of the replacement candidate air cooler 5.

[0034] As shown in FIG. 3 , the air calculation unit 40 is made up of an air cooler cooling capacity calculation unit 21, a temperature T3′ calculation unit 43 on the downstream side of the air cooler 5 after the compression mechanism unit 3 has been replaced, a determination unit 44 that determines whether the temperature T3′ is lower than the maximum allowable temperature Tdmax of compressed air, an effect calculation unit 45, a processing unit 46, a compression mechanism unit operation upper limit calculation unit 47, and an air cooler required specification calculation unit 48.

[0035] The calculation unit 18 first calculates the amount of heat cooled by the air cooler 5 in the cooling capacity calculation unit 21 of the air cooler based on the various data collected by the data collection unit 17 and information on the currently installed compression mechanism unit 3 recorded in the first database 20.

[0036] Next, in the temperature T3' calculation unit 43, based on the amount of heat cooled by the air cooler 5 calculated by the cooling capacity calculation unit 21 and information related to the replacement candidate compression mechanism unit 3 recorded in the second database 22, the air temperature T3' of the compressed air downstream of the air cooler 5 after replacement with the replacement candidate compression mechanism unit 3 is predicted and calculated for all operating conditions under which the quality of the air compressor 1 must be guaranteed.

[0037] Furthermore, the judgment unit 44 calculates the magnitude relationship between the air temperature T3' downstream of the air cooler 5 predicted and calculated by the temperature T3' calculation unit 43 and a predetermined maximum temperature (e.g., 100°C) set in advance under all operating conditions, and determines whether the air cooler 5 needs to be replaced or whether the operating conditions of the compression mechanism unit 3 after replacement need to be restricted.

[0038] If it is within the range, the effect calculation unit 45 compares the information recorded in the first database 20 and the second database 22, and outputs and displays on the display device 19 the energy saving effect and electricity cost reduction effect resulting from replacing the compression mechanism unit 3, as well as the cost required to replace the compression mechanism unit 3.

[0039] Here, if the rotation speed of the air cooling fan 6 increases because the amount of compressed air increases due to replacement of the compression mechanism unit 3, the resulting increase in power consumption of the air cooling fan 6 is deducted from the energy-saving effect due to replacement of the compression mechanism unit 3 described above.

[0040] On the other hand, even when the rotation speed of the air cooling fan 6 is at its maximum value, if the air temperature downstream of the air cooler 5 after replacement with the replacement candidate compression mechanism unit 3 exceeds a predetermined maximum temperature, the processing unit 46 performs two systems of calculation processing so that two display contents can be selected for display.

[0041] The first calculation process and display content is that the compression mechanism unit operation upper limit calculation unit 47 searches the second database 22 for the upper limit rotation speed (upper limit load rate) of the compression mechanism unit 3 that is a candidate for replacement, at which the air temperature downstream of the air cooler 5 will be below the upper limit temperature, and outputs and displays the energy saving effect and electricity bill reduction effect under those conditions, as well as the cost required to replace the compression mechanism unit 3.

[0042] The second calculation process and display content involves the air cooler required specification calculation unit 48 searching for and displaying replacement candidates for the air cooler 5, which will have an air temperature downstream of the air cooler 5 below an upper limit temperature, from the information recorded in the third database 23, and calculating the compressed air temperature downstream of the replacement candidate air cooler 5 when replaced with the replacement candidate air cooler 5 based on the information recorded in the second database 22 and the third database 23, calculating whether the compressed air temperature is higher or lower than the upper limit value, and determining whether replacement is possible, as well as calculating, outputting, and displaying the energy-saving effects and electricity bill reduction effects obtained when the air cooler 5 is also replaced, and the cost required for replacing the compression mechanism unit 3 and the air cooler 5.

[0043] Next, we will explain how to calculate the energy-saving performance of the compression mechanism 3. The instantaneous energy-saving performance is calculated by dividing the total input power L [W] to the air compressor by the discharge air volume Q air [m 3 / min], the following ratio input η c [W / (m 3 / min)].

[0044]

number

[0045] The first database 20 has previously stored therein the relationship between the input power and the current value and rotation speed of the motor 4. This allows the effect calculation unit 45, the compression mechanism operation upper limit calculation unit 47, or the required specification calculation unit 48 to calculate the input power of the motor 4 based on the rotation speed and current value of the motor 4 detected by the first rotation speed detection unit 11.

[0046] Similarly, for the air cooling fan 6, the input power can be calculated by the air cooler required specification calculation unit 48 from the relationship between the current value and rotation speed, which are implemented in the third database 23, and the input power.

[0047] The total input power L of the air compressor 1 is the sum of the input power of the motor 4 that rotates the compression mechanism 3 and the input power of the air cooling fan 6 .

[0048] Discharge air volume Q air is calculated in cooling capacity calculation unit 21 from the relationship between the rotation speed and discharge air volume of compression mechanism unit 3 shown in Figure 4, which is implemented in first database 20. Since the discharge air volume of air compressor 1 is particularly strongly affected by the outside air temperature, suction pressure, and discharge pressure, it is calculated from the relationship between the rotation speed and discharge air volume of compression mechanism unit 3, which is implemented in first database 20, based on the output values ​​of first temperature sensor 13, first pressure sensor 9, second pressure sensor 10, and first rotation speed detection unit 11.

[0049] The annual electricity cost X [yen] (operating cost) is calculated by the effect calculation unit 45, the compressor mechanism operation upper limit calculation unit 47, or the required specification calculation unit 48. t [m 3 ], ratio input η c This can be calculated using the following formula (2) by multiplying the contracted power rate A [¥ / kWh] by the contracted power rate A.

[0050]

number

[0051] In addition, the specific input η of the replacement candidate compression mechanism part 3 c Since the effect of replacing the compression mechanism unit 3 has already been evaluated before the replacement of the compression mechanism unit 3, it is possible to calculate the effect of reducing the electricity cost by replacing the compression mechanism unit 3 using equation (2).

[0052] Furthermore, from this electricity bill reduction effect, various energy conservation effects such as the amount of reduction in power consumption and the amount of CO2 reduction achieved by that reduction can be calculated.

[0053] The amount of heat cooled by the air cooler 5 in the cooling capacity calculation unit 21, q air Explain how to calculate [W].

[0054] Cooling heat amount q air is the density ρ of compressed air calculated based on the output values ​​of the second pressure sensor 10 and the second temperature sensor 14. air [kg / m 3 ] and specific heat c air , the discharge air volume Q obtained by the above method air [m 3 / min] and the difference between the output values ​​of the second temperature sensor 14 and the third temperature sensor 15, using the following formula (3). Note that the first database 20 contains physical property values ​​of compressed air, and the density ρ of compressed air is calculated based on the output values ​​of the second pressure sensor 10 and the second temperature sensor 14. air [kg / m 3 ] and specific heat c air It is possible to calculate [J / (kg·K)].

[0055]

number

[0056] The third database 23 stores the relationship between the discharge air volume and the rotation speed of the air cooling fan 6 shown in Fig. 5 for each pressure ratio condition when the air compressor 1 is new. Therefore, it is desirable for the monitoring device 16 to periodically (for example, once a month) evaluate the relationship between the discharge air volume and the rotation speed of the air cooling fan 6 based on monitoring data obtained when the actual machine is in use.

[0057] Figure 6 shows the relationship between the discharge air volume and the rotation speed of the air cooling fan 6 when the pressure ratio is 7.0. The dashed line represents the specifications when the product was new, and the solid line represents the evaluation results (point cloud) after the product has been used for a certain period of time and an approximation calculated from these values. As the air cooler 5 deteriorates over time, its cooling efficiency decreases, and the condition for the discharge air volume to reach the maximum rotation speed of the air cooling fan 6 decreases.

[0058] Figure 7 shows the relationship between the rotation speed of the air cooling fan 6 and the amount of cooled heat calculated by equation (3) under the same conditions as in Figure 6. The amount of cooled heat of the air cooler 5 at the maximum rotation speed of the air cooling fan 6 is the maximum cooling capacity of the air cooler 5 after deterioration over time. When the compression mechanism 3 is replaced with a new one or one with higher performance, if it is expected that the maximum value of the discharge air temperature calculated from the maximum cooling capacity of the air cooler 5 shown in Figure 7, which is implemented in the third database 23, will exceed the product quality level, i.e., the upper limit temperature, the following procedure will be followed.

[0059] That is, the methods are divided into lowering the upper limit rotation speed (upper limit load rate) of the compression mechanism 3, replacing the air cooler 5 with a more efficient one registered in the third database 23, and replacing the air cooling fan 6 with a more efficient one, and the energy saving effect and electricity bill reduction effect of each case, as well as the cost required for the replacement, are output and displayed on the display device 19.

[0060] As described above, when replacing the compression mechanism 3 of the air compressor 1 with a new one or one with higher performance, it is possible to estimate whether an increase in the amount of discharged air will cause the supply temperature of the compressed air to fall below the upper limit temperature, which is the quality standard of the product, and if it will exceed the upper limit temperature, to take measures in advance and estimate the energy saving effect taking this into consideration, thereby making it possible to present the energy saving effect and cost to the customer while still satisfying the quality standard.

[0061] Note that the first rotation speed detection unit 11 and the second rotation speed detection unit 12 are not limited to those that directly detect the rotation speed using a pulse signal or the like, but may also use an indirect detection method in which the rotation speed is estimated based on the command frequency of the inverter, or calculated based on the operating conditions of the air compressor 1 and the detected values ​​of the input current and power of the motor 4 and the air cooling fan 6.

[0062] The air cooler 5 may be of a water-cooled type instead of an air-cooled type as in this embodiment. In this case, the air cooling fan 6 in this embodiment replaces an electromagnetic valve or the like that controls the flow rate of cooling water, and determines the maximum amount of cooling heat of the air cooler 5 when the valve is fully open.

[0063] Next, the effects of this embodiment will be described.

[0064] The air compressor 1 for compressing air of the first embodiment of the present invention described above includes a motor 4, a compression mechanism unit 3 that compresses air by rotation of the motor 4, an air cooler 5 that cools the compressed air compressed by the compression mechanism unit 3, a state quantity detection unit that detects a state quantity of the compressed air in the compression mechanism unit 3, and a monitoring device 16 that monitors the state of the air compressor 1, and the monitoring device 16 calculates the cooling heat quantity of the air cooler 5 based on the state quantity of the compressed air detected by the state quantity detection unit, calculates the operating conditions of the air cooler 5 when the compression mechanism unit 3 is replaced from the cooling heat quantity, calculates the operating cost when the compression mechanism unit 3 is replaced based on the operating conditions, calculates the replacement cost and energy saving effect when the compression mechanism unit 3 is replaced based on the operating cost, and displays the calculated replacement cost and energy saving effect on a display device 19.

[0065] In a normal machine, the amount of exhaust heat tends to decrease as the performance improves, whereas in a gas compressor such as the air compressor 1 illustrated in the examples, the amount of exhaust heat tends to increase as the performance improves (i.e., the amount of compressed air increases). Therefore, when simply upgrading parts, it is unclear whether the expected cost-effectiveness, such as energy saving effects, will be obtained.

[0066] In contrast, according to the present invention, it is possible to estimate the cooling capacity of a compressed air cooler that has deteriorated over time based on various state quantities of the gas compressor, and when replacing the compression mechanism 3 with a new one or one with higher performance, it becomes possible to determine whether the cooling capacity satisfies the required capacity without disassembling and inspecting the air compressor 1. This makes it possible to more accurately estimate than before the various effects, such as energy saving effects and electricity bill reduction effects, that result from upgrading the compression mechanism 3, without disassembling the air compressor 1.

[0067] For example, when the compression mechanism part of a gas compressor, which has a particularly large impact on power consumption, is replaced with a new or more powerful part, in addition to the energy-saving effect or power consumption reduction effect of the replacement, it becomes possible to estimate the supply temperature of compressed air and determine whether the quality level can be achieved.

[0068] The air compressor 1 further includes a first database 20 relating to the rotational speed of the motor 4 and the amount of compressed air discharged. The state quantity detection unit detects the value of the current input to the motor 4 and the rotational speed of the motor 4. The monitoring device 16 calculates the operating cost of the compression mechanism unit 3 before replacement based on the current value and rotational speed detected by the state quantity detection unit and the amount of compressed air discharged retrieved from the first database 20. This makes it possible to more accurately determine the difference in operating cost due to replacement, and to provide the user of the air compressor 1 with more information about the effects obtained by replacement.

[0069] Furthermore, the state quantity detection unit detects the temperature and pressure of the compressed air upstream of the air cooler 5 and the temperature of the compressed air downstream of the air cooler 5, and the monitoring device 16 calculates the amount of cooled heat based on the temperature and pressure of the compressed air upstream of the air cooler 5 and the temperature of the compressed air downstream of the air cooler 5 detected by the state quantity detection unit, thereby enabling accurate calculation of the amount of cooled heat.

[0070] The monitoring device 16 also includes a second database 22 relating to the rotational speed and compressed air discharge volume of the compression mechanism unit 3 of the replacement candidate, and calculates the operating cost of the compression mechanism unit 3 of the replacement candidate based on the discharge volume of the compression mechanism unit 3 before replacement, the discharge volume retrieved from the second database 22, and the rotational speed of the compression mechanism unit 3 of the replacement candidate.This makes it possible to reflect the operating conditions after replacement in the evaluation results, and provides information for making more appropriate decisions such as whether or not to perform replacement.

[0071] Furthermore, the monitoring device 16 predicts the temperature of the compressed air downstream of the air cooler 5 after replacement with the compression mechanism unit 3 that is a candidate for replacement, and calculates the magnitude relationship with a preset upper limit value, thereby making it possible to reflect the effect of replacing the air cooler 5 in conjunction with replacement of the compression mechanism unit 3, and further provide information for making decisions such as whether or not to perform an appropriate replacement.

[0072] In addition, the monitoring device 16 is further provided with a third database 23 relating to the cooling performance of the replacement candidate air cooler 5, and by calculating the temperature of the compressed air downstream of the replacement candidate air cooler 5 when replaced with the replacement candidate air cooler 5 and calculating the magnitude relationship with the upper limit value, it is possible to determine whether there are any problems with replacing with the replacement candidate air cooler 5, and to obtain more accurate energy saving effects, electricity bill reduction effects, etc.

[0073] <Second Example> A gas compressor, a gas compressor monitoring device, and a gas compressor monitoring method according to a second embodiment of the present invention will be described with reference to Figures 8 to 10. This embodiment relates to an air compressor, just like the first embodiment, and the same parts as in the first embodiment will be described with the same reference numerals.

[0074] The air compressor 1A of this embodiment shown in FIG. 8 is configured such that, in addition to the air compressor 1 of the first embodiment, a configuration for supplying lubricating oil to the inside of the compression mechanism 3 is provided, and a lubricating oil calculation unit 32 related to the lubricating oil cooler 25 is added.

[0075] The purpose of supplying lubricating oil to the compression mechanism 3 is to lubricate the sliding parts, seal minute internal gaps, and cool the compressed air.

[0076] The lubricating oil supplied into the compression mechanism 3 is discharged from the compression mechanism 3 in a state mixed with the discharge air, and flows into the centrifugal separator 24 .

[0077] The centrifugal separator 24 separates the compressed air compressed by the compression mechanism 3 from the liquid supplied to the compression mechanism 3.

[0078] The compressed air separated in the centrifugal separator 24 flows into the compressed air pipe 8, is cooled to a predetermined temperature in the air cooler 5, and is then supplied to an external compressed air consuming device (not shown).

[0079] The lubricating oil separated in the centrifugal separator 24 flows into the lubricating oil cooler 25, where it is cooled to a predetermined temperature, and then passes through the lubricating oil filter 26 before flowing back into the compression mechanism 3. The centrifugal separator 24, the lubricating oil cooler 25, the lubricating oil filter 26, and the compression mechanism 3 are connected by a lubricating oil pipe 27.

[0080] As with the compressed air piping 8, in order to detect the temperature and pressure of the liquid upstream of the lubricant oil cooler 25 and the temperature of the liquid downstream of the lubricant oil cooler 25, the lubricant oil cooler 25 also has a fourth temperature sensor 28 and a fifth temperature sensor 29 on the upstream and downstream sides, respectively, as state quantity detection units, and also has a lubricant oil cooling fan 30 that blows cooling air to the lubricant oil cooler 25 and a third rotational speed detection unit 31 that detects the rotational speed and current value of the lubricant oil cooling fan 30.

[0081] The configuration of the monitoring device 16A is shown in Fig. 9. The monitoring device 16A is composed of a data collection unit 17A that collects output values ​​from various sensors, a calculation unit 18A that calculates energy-saving performance and the like based on the collected data, and a display device 19 that outputs and displays the calculation results of the calculation unit 18A (energy-saving effect, cost reduction effect obtained by replacing the compression mechanism unit 3).

[0082] The data collection unit 17A is a part that accepts input of output values ​​from the first pressure sensor 9, the second pressure sensor 10, the first rotational speed detection unit 11, the second rotational speed detection unit 12, the first temperature sensor 13, the second temperature sensor 14, the third temperature sensor 15, as well as the fourth temperature sensor 28, the fifth temperature sensor 29, and the third rotational speed detection unit 31.

[0083] In the monitoring device 16A of the present embodiment, in addition to performing the calculation processing of the monitoring device 16 of the first embodiment, the monitoring device 16A calculates the cooling heat quantity of the lubricant oil cooler 25 based on the state quantity of the liquid detected by the state quantity detection unit, calculates the operating conditions of the lubricant oil cooler 25 when the compression mechanism unit 3 is replaced from the cooling heat quantity, calculates the operating cost when the compression mechanism unit 3 is replaced based on the operating conditions, calculates the replacement cost and energy saving effect when the compression mechanism unit 3 is replaced based on the operating cost, and executes processing to display the calculation results of the replacement cost and energy saving effect on the display device 19.

[0084] 10 shows the configuration of the calculation unit 18A of this embodiment. The calculation unit 18A includes an air calculation unit 40 that calculates the energy saving effect and the like resulting from replacing the compression mechanism unit 3 from the amount of heat cooled by the air cooler 5, a first database 20, a second database 22, and a third database 23, as well as a lubricant oil calculation unit 32 that calculates the energy saving effect and the like resulting from replacing the compression mechanism unit 3 from the lubricant oil cooler 25, and a fourth database 41 that stores information on the cooling performance of the lubricant oil cooler 25 that is a replacement candidate.

[0085] In this embodiment, the monitoring device 16A can calculate the amount of cooled heat based on the temperature and pressure of the liquid upstream of the lubricant oil cooler 25 and the temperature of the liquid downstream of the lubricant oil cooler 25, which are detected by the state quantity detection unit. The monitoring device 16A can also predict the temperature of the liquid downstream of the lubricant oil cooler 25 after replacement with the replacement candidate compression mechanism unit 3, and calculate the magnitude relationship between this temperature and a preset upper limit value. Furthermore, the monitoring device 16A can calculate the temperature of the liquid downstream of the replacement candidate lubricant oil cooler 25 when replaced with the replacement candidate lubricant oil cooler 25, and calculate the magnitude relationship between this temperature and the upper limit value.

[0086] As shown in FIG. 10, the lubricant oil calculation unit 32 is composed of a lubricant oil cooler cooling capacity calculation unit 33, a temperature T5' calculation unit 34 for the temperature T5' downstream of the lubricant oil cooler 25 after the compression mechanism unit 3 has been replaced, a determination unit 35 for determining whether the temperature T5' is lower than the maximum allowable temperature Tomax of the lubricant oil, an effect calculation unit 36, a processing unit 37, an operation upper limit calculation unit 38 for the compression mechanism, a required specification calculation unit 39 for the lubricant oil cooler 25, and the like.

[0087] The processing of these parts is different from that of the air calculation part 40 for the air cooler 5 in that the only difference between the functions of the lubricant calculation part 32 and the air calculation part 40 is that the medium to be cooled in the air calculation part 40 described in the first embodiment is replaced by lubricant oil instead of compressed air, and therefore the explanation will be omitted.

[0088] The other configurations and operations are substantially the same as those of the gas compressor, gas compressor monitoring device, and gas compressor monitoring method of the first embodiment described above, and details thereof will be omitted.

[0089] In an oil-lubricated air compressor 1A such as that of this embodiment, quality standards regarding the upper limit temperature are set not only for the compressed air but also for the lubricant, from the viewpoint of preventing oxidation and deterioration of the lubricant.

[0090] When the compression mechanism 3 is replaced with a new one or one with higher performance than the new one, the amount of discharged air increases, and the temperature of the lubricating oil that exchanges heat with the high-temperature discharged air tends to rise. If the lubricating oil cooler 25 is left installed, there is a concern that the upper limit temperature may be exceeded.

[0091] Therefore, when replacing the compression mechanism 3 of the air compressor 1A with a new one or one with higher performance, the lubricant calculation unit 32 in this embodiment estimates whether the increase in the discharge air volume will cause the maximum temperature of the lubricant to fall below the upper limit temperature, which is the quality level of the product, and if it will exceed the upper limit temperature, it estimates countermeasures in advance and energy-saving effects taking this into consideration, making it possible to present the energy-saving effects and costs to the customer while still satisfying the quality level.

[0092] <Other> It should be noted that the present invention is not limited to the above-described embodiment, and includes various modifications. The above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the described configurations. [Explanation of symbols]

[0093] 1,1A...Air compressor 2...Suction filter 3...Compression mechanism 4...Motor 5...Air cooler (gas cooler) 6...Air cooling fan 7...Discharge filter 8...Compressed air piping 9...First pressure sensor (state quantity detection unit) 10...Second pressure sensor (state quantity detection unit) 11...First rotation speed detection unit (state quantity detection unit) 12...Second rotation speed detection unit (state quantity detection unit) 13...First temperature sensor (state quantity detection unit) 14... Second temperature sensor (state quantity detection unit) 15...Third temperature sensor (state quantity detection unit) 16,16A…Monitoring device (monitoring section) 17, 17A...Data collection section 18,18A…Arithmetic unit 19...Display device 20...First Database 21…Cooling capacity calculation section 22...Second database 23...Third Database 24...Centrifuge (separation section) 25…Lubricating oil cooler (liquid cooler) 26...Lubricating oil filter 27…Lubricating oil piping 28...Fourth temperature sensor (state quantity detection unit) 29... Fifth temperature sensor (state quantity detection unit) 30...Lubricant cooling fan 31...Third rotation speed detection unit (state quantity detection unit) 32...Lubricant calculation section 33…Cooling capacity calculation section 34...Arithmetic section 35…Judgment section 36...Effect calculation section 37...Processing section 38...Operation upper limit calculation unit 39...Required specification calculation section 40...Air calculation unit 41...The fourth database 43...Arithmetic section 44...Judgment section 45...Effect calculation section 46...Processing section 47...Compression mechanism operation upper limit calculation unit 48...Required specification calculation section

Claims

1. A gas compressor that compresses gas, A motor; a compression mechanism that compresses gas by rotation of the motor; a gas cooler that cools the compressed gas compressed by the compression mechanism; a state quantity detection unit that detects a state quantity related to the operation of the gas compressor; a monitoring unit that monitors the state of the gas compressor, The monitoring unit a cooling heat quantity of the gas cooler based on the state quantity of the compressed gas detected by the state quantity detection unit; an operating condition of the gas cooler when the compression mechanism unit is replaced from the cooling heat quantity; an operating cost when the compression mechanism unit is replaced based on the operating conditions; a replacement cost and an energy saving effect when the compression mechanism unit is replaced based on the operating cost; and a display unit that displays the calculation results of the replacement cost and the energy saving effect. Gas compressor.

2. 2. The gas compressor according to claim 1, a first database relating to the rotation speed of the motor and the discharge amount of the compressed gas; the state quantity detection unit detects a current value input to the motor and a rotation speed of the motor; The monitoring unit calculates an operating cost of the compression mechanism unit before replacement based on the current value and the rotational speed detected by the state quantity detection unit and the discharge amount of the compressed gas searched from the first database. Gas compressor.

3. 2. The gas compressor according to claim 1, the state quantity detection unit detects a temperature and a pressure of the compressed gas upstream of the gas cooler and a temperature of the compressed gas downstream of the gas cooler; The monitoring unit calculates the amount of cooled heat based on the temperature and pressure of the compressed gas upstream of the gas cooler and the temperature of the compressed gas downstream of the gas cooler, which are detected by the state quantity detection unit. Gas compressor.

4. 2. The gas compressor according to claim 1, a second database relating to the rotation speed of the compression mechanism unit that is a replacement candidate and the discharge amount of the compressed gas; The monitoring unit calculates the operating cost of the replacement candidate compression mechanism unit based on the discharge amount of the compression mechanism unit before replacement, the discharge amount searched from the second database, and the rotation speed of the replacement candidate compression mechanism unit. Gas compressor.

5. 5. The gas compressor according to claim 4, The monitoring unit predicts a temperature of the compressed gas downstream of the gas cooler after replacement with the replacement candidate compression mechanism unit, and calculates a magnitude relationship between the temperature and a preset upper limit value. Gas compressor.

6. 6. The gas compressor according to claim 5, a third database relating to the cooling performance of candidate gas coolers for replacement; The monitoring unit calculates the temperature of the compressed gas downstream of the replacement candidate gas cooler when the replacement candidate gas cooler is replaced with the replacement candidate gas cooler, and calculates the magnitude relationship between the temperature and the upper limit value. Gas compressor.

7. A gas compressor that compresses gas, A motor; a compression mechanism that compresses gas by rotation of the motor; a separation unit that separates the compressed gas compressed by the compression mechanism unit from the liquid supplied to the compression mechanism unit; a liquid cooler that cools the liquid separated in the separation unit; a state quantity detection unit that detects a state quantity related to the operation of the gas compressor; a monitoring unit that monitors the state of the gas compressor, The monitoring unit a cooling heat quantity of the liquid cooler based on the state quantity of the liquid detected by the state quantity detection unit; an operating condition of the liquid cooler when the compression mechanism unit is replaced based on the cooling heat quantity; an operating cost when the compression mechanism unit is replaced based on the operating conditions; a replacement cost and an energy saving effect when the compression mechanism unit is replaced based on the operating cost; and a display unit that displays the calculation results of the replacement cost and the energy saving effect. Gas compressor.

8. 8. The gas compressor according to claim 7, a first database relating to the rotation speed of the motor and the discharge amount of the compressed gas; the state quantity detection unit detects a current value input to the motor and a rotation speed of the motor; The monitoring unit calculates an operating cost of the compression mechanism unit before replacement based on the current value and the rotational speed detected by the state quantity detection unit and the discharge amount of the compressed gas searched from the first database. Gas compressor.

9. 8. The gas compressor according to claim 7, the state quantity detection unit detects a temperature and a pressure of the liquid upstream of the liquid cooler and a temperature of the liquid downstream of the liquid cooler; The monitoring unit calculates the amount of cooled heat based on the temperature and pressure of the liquid upstream of the liquid cooler and the temperature of the liquid downstream of the liquid cooler, which are detected by the state quantity detection unit. Gas compressor.

10. 8. The gas compressor according to claim 7, a second database relating to the rotation speed of the compression mechanism unit that is a replacement candidate and the discharge amount of the compressed gas; The monitoring unit calculates the operating cost of the replacement candidate compression mechanism unit based on the discharge amount of the compression mechanism unit before replacement, the discharge amount searched from the second database, and the rotation speed of the replacement candidate compression mechanism unit. Gas compressor.

11. 11. The gas compressor according to claim 10, The monitoring unit predicts the temperature of the liquid downstream of the liquid cooler after replacement with the replacement candidate compression mechanism unit, and calculates the magnitude relationship between the temperature and a preset upper limit value. Gas compressor.

12. 12. The gas compressor according to claim 11, a fourth database relating to the cooling performance of the liquid cooling unit as a replacement candidate; The monitoring unit calculates the temperature of the liquid downstream of the replacement candidate liquid cooler when the replacement candidate liquid cooler is replaced, and calculates the magnitude relationship between the temperature and the upper limit value. Gas compressor.

13. A monitoring device for a gas compressor that compresses gas, comprising: calculating a cooling heat quantity of a gas cooler that cools the compressed gas compressed by a compression mechanism that compresses the gas by rotation of a motor based on a state quantity of the compressed gas in the compression mechanism; calculating an operating condition of the gas cooler when the compression mechanism unit is replaced based on the amount of cooled heat; calculating an operating cost in the case where the compression mechanism unit is replaced based on the operating conditions; calculating replacement costs and energy-saving effects when the compression mechanism unit is replaced based on the operating costs; The calculation results of the replacement cost and the energy saving effect are displayed on a display unit. Gas compressor monitoring device.

14. A method for monitoring a gas compressor that compresses gas, comprising: calculating a cooling heat quantity of a gas cooler that cools the compressed gas compressed by a compression mechanism that compresses the gas by rotation of a motor, based on a state quantity of the compressed gas in the compression mechanism; calculating an operating condition of the gas cooler when the compression mechanism unit is replaced based on the amount of cooled heat; calculating an operating cost when the compression mechanism unit is replaced based on the operating conditions; calculating a replacement cost and an energy saving effect when the compression mechanism unit is replaced based on the operating cost; and displaying the calculation results of the replacement cost and the energy saving effect on a display unit. A method for monitoring a gas compressor.

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