JP6592129B2 - Compressor - Google Patents

Description

  The present invention relates to a compressor that compresses a fluid such as air using a motor as a power source.

  In a compressor such as a scroll compressor, it is necessary to inspect components such as bearings and replace grease, seals, etc. every predetermined operation time. In the conventional products, maintenance is performed every predetermined operation time or every predetermined operation period according to the pressure specifications, but the life of grease and bearings depends on the pressure and temperature during the actual operation of the compressor. Will change.

  As a conventional technique for informing the inspection time by changing the maintenance time in consideration of the pressure and the ambient temperature, Patent Document 1 discloses "a motor, a compression unit that is driven by the motor and discharges compressed gas, and the compression unit. Driving time integrating means for integrating the driving time of the compressor, and inspection time informing means for informing the inspection time of the compression section using the accumulated driving time by the driving time integrating means, wherein the inspection time informing means comprises the compression time An integrated drive time correcting means for correcting the integrated drive time by the drive time integrating means according to the operating conditions of the unit, and when the corrected integrated drive time by the integrated drive time correcting means has reached a predetermined inspection time A compressor characterized by comprising a notification signal output means for outputting a notification signal for notifying the inspection time, wherein the compression section has a pressure in a tank for storing the compressed gas. The upper limit pressure is variably set while stopping when the pressure rises above the limit pressure and driving when the pressure falls below the lower limit pressure, and the integrated drive time correction means sets the upper limit pressure in advance. A compressor configured to correct so as to extend the accumulated drive time by the drive time accumulating means according to the upper limit pressure when set to a pressure higher than the upper limit pressure. ”(Claims 1 and 4) Has been.

JP 2006-97655 A

  In the current product, the maintenance time is set according to the pressure specifications of the product, but this method does not change the maintenance time according to the actual usage status (pressure, temperature, etc.) of the compressor. Therefore, it is necessary to set the maintenance time, and the maintenance time becomes shorter than the period during which operation is possible.

  In the invention described in Patent Document 1, the corrected integrated drive time is calculated in consideration of the upper limit pressure in the tank and the ambient temperature, and the maintenance time is warned when the corrected integrated drive time exceeds the set value. However, the internal temperature of the compressor body changes with pressure. For example, when the pressure increases, the internal temperature increases. It is the internal temperature that affects the components of the compressor body. For this reason, even if the ambient temperature is detected, it is different from the actual internal temperature, and it is difficult to accurately calculate the maintenance time.

  An object of the present invention is to solve these problems and to provide a compressor capable of calculating an accurate maintenance time.

In order to solve the above problems, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-described problems. If an example of the compressor of the present invention is given,
A compressor body for compressing fluid, a motor for driving the compressor main body, a temperature sensor for detecting the temperature of the compressor, a pressure sensor for detecting the pressure of the compressed fluid which is output from the compressor main body, the control With circuit,
The control circuit includes a temperature maintenance coefficient Kmt based on the temperature of the compressor, a pressure maintenance coefficient Kmp based on the pressure of the compressed fluid, a rotation speed maintenance coefficient Kmr based on the rotation speed of the motor, From the operation time T, the corrected operation time Tm is expressed by the following formula:
Tm = T × 1 / (Kmt × Kmp × Kmr)
The cumulative operation time is obtained from the integrated value of the corrected operation time Tm from the start of use of the compressor or from the start of use after maintenance. When the cumulative operation time reaches a preset maintenance set time, a maintenance instruction signal It is characterized by putting out .

  Moreover, the compressor of this invention WHEREIN: It is preferable that the said calculation part changes the weighting of the said temperature according to the operation rate of the said compressor main body.

  According to the present invention, an accurate maintenance time can be obtained in consideration of the internal temperature of the compressor body. When the compressor is used at a high load, the maintenance time is shortened, so that failure can be reliably prevented. Further, when the compressor is used at a low load, the maintenance time is extended, so that the period until the maintenance is performed is extended, resulting in customer merit.

It is a block block diagram of the compressor of Example 1 of this invention. It is a correction map which shows the relationship between the pressure of a compressed fluid, and a pressure maintenance coefficient. It is a correction map which shows the relationship between the ambient temperature of a compressor and a temperature maintenance coefficient in consideration of pressure. It is a block block diagram of the compressor of Example 2 of this invention. It is a correction map which shows the relationship between the rotational speed ratio of a compressor, and a rotational speed maintenance coefficient. It is a figure which shows starting and a stop of a compressor. It is a correction map which shows the relationship between the ambient temperature of a compressor and a temperature maintenance coefficient in consideration of an operation rate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that components having the same function are denoted by the same names and reference numerals in the drawings for describing the embodiments, and repetitive description thereof is omitted.

  The system of the present embodiment will be described with reference to FIGS.

  FIG. 1 is a block diagram illustrating a compressor in Embodiment 1 of the present invention. The compressor 1 includes a scroll compressor body 2 that compresses air, a motor 3 that drives the compressor body, a control circuit 4 that controls the entire compressor 1, and an air tank 5 that stores air compressed by the compressor body 2. , A pressure sensor 6 that detects the pressure of the air tank 5, a temperature sensor (ambient) 7 that detects the ambient temperature of the compressor 1, a temperature sensor (main body) 8 that detects the surface temperature of the compressor body 2, a set value, etc. It is composed of a storage circuit 9 for storing data and a display 10 for informing the maintenance execution time.

  In this embodiment, the compressor main body 2 is a scroll compressor, but the type of the compressor main body is not limited to the scroll compressor. Further, although the pressure sensor 6 detects the pressure of the air tank 5, the detection location may be anywhere on the air circuit in the compressor 1 on the output side of the compressor body 2, and may be the case where there is no air tank 5.

  The control circuit 4 uses the pressure detected by the pressure sensor 6 to drive the motor 3 when the fluid pressure in the air tank 5 drops to the lower limit pressure, and stops the motor 3 when the fluid pressure rises to the upper limit pressure. Thus, the pressure in the air tank 5 is kept between the upper limit pressure and the lower limit pressure. Further, a calculation unit (not shown) in the control circuit obtains the operation time of the compressor, and corrects the operation time according to the pressure of the compressed fluid and the ambient temperature, as described below, to obtain the corrected operation time. . Then, the accumulated operation time is obtained by accumulating the corrected operation time from the start of use of the compressor or from the start of use after maintenance, and a maintenance instruction signal is issued when the accumulated operation time reaches a preset maintenance set time.

  FIG. 2 is a correction map showing an example of the relationship between the pressure of the compressed fluid detected by the pressure sensor 6 and the pressure maintenance coefficient Kmp, which is a correction coefficient for the operation time. When the pressure in the tank and the related compressor main body rises, it becomes severe operating conditions, and wear and damage are likely to occur in parts and the like constituting the compressor main body. Therefore, a correction coefficient as shown in the figure is used according to the pressure of the compressed fluid. The correction map of FIG. 2 is obtained by calculating and graphing the deterioration of the bearing and grease at two inflection points, but may be obtained by experiment.

  FIG. 3 is a correction map showing an example of the relationship between the ambient temperature detected by the temperature sensor (ambient) 7 and the temperature maintenance coefficient Kmt which is a correction coefficient for the operation time. When the temperature of the compressor body rises, it becomes severe operating conditions, and grease and seals used in the compressor body tend to deteriorate. Therefore, a correction coefficient as shown in the figure is used according to the ambient temperature. This map includes a curve 3-1 used when the pressure P of the compressed fluid is larger than the threshold value Pk, and a curve 3-2 used when the pressure P of the compressed fluid is equal to or less than the threshold value Pk. The correction map of FIG. 3 may also be obtained in advance by calculation or experiment. 2 or 3 may be stored in advance in the storage circuit 9 as a table, or may be stored in the storage circuit 9 as a calculation formula.

  In the operation of this embodiment, the control circuit 4 calculates the pressure maintenance coefficient Kmp from the detection value of the pressure sensor 6 using the correction map of FIG. Similarly, the control circuit 4 calculates the temperature maintenance coefficient Kmt from the detected value of the temperature sensor (ambient) 7 using the correction map of FIG. When calculating the temperature maintenance coefficient Kmt, the inflection point of the temperature maintenance coefficient Kmt is changed in consideration of the internal pressure of the compressor body, and if the detected value P of the pressure sensor 6 exceeds the threshold value Pk, the curve 3- 1 is used, and the curve 3-2 is used when it is equal to or less than the threshold value Pk. These correction coefficients are calculated based on a correction map table or a calculation formula stored in the storage circuit 9.

  A calculation unit (not shown) in the control circuit 4 obtains a corrected operation time Tm from the following equation 1 from the calculated pressure maintenance coefficient Kmp, temperature maintenance coefficient Kmt, and operation time T of the compressor body 2.

Tm = T × 1 / (Kmp × Kmt) (Equation 1)
The accumulated operation time is obtained from the integrated value of the corrected operation time Tm from the start of use of the compressor or from the start of use after maintenance, and a maintenance instruction signal is issued when the accumulated operation time reaches a preset maintenance set time.

  The display 10 displays the accumulated operation time obtained by the control circuit 4 and notifies the user that it is the maintenance time according to the maintenance instruction signal.

  The pressure maintenance coefficient Kmp according to the pressure of the compressed fluid in FIG. 2 takes a large value in a region where the pressure is low, decreases as the pressure increases from the inflection point, and becomes a small value in a region where the pressure is high. Therefore, from Equation 1, when the pressure is high, the operation time is corrected to increase, and when the pressure is low, the operation time is corrected to decrease. Therefore, the maintenance time is shortened in a high pressure operation state where the deterioration of the components of the compressor body is large, and the maintenance time is extended in a low pressure operation state where the deterioration of the components of the compressor body is small.

  The temperature maintenance coefficient Kmt according to the ambient temperature in FIG. 3 takes a large value (1.0) in the region where the ambient temperature is low, and decreases with increasing temperature from the inflection point. Further, the inflection point varies depending on the pressure, and a curve 3-1 that decreases from a low temperature is used when the pressure is larger than the threshold Pk, and a curve 3-2 that decreases at a high temperature when the pressure is equal to or lower than the threshold Pk. Is used. Therefore, from Equation 1, when the ambient temperature is high, correction is performed so as to increase the operation time, and when the pressure is high, correction is performed so as to increase the operation time from a lower ambient temperature. Therefore, the maintenance time is shortened in a high-temperature operating state where the components of the compressor body are greatly deteriorated, and the correction is made so that the maintenance time is further shortened at high pressures where the internal temperature of the compressor body rises. Done. Since the ambient temperature of the compressor is different from the internal temperature, the maintenance time corresponding to the actual internal temperature can be obtained by switching the correction coefficient according to the pressure.

  Switching between the curve 3-1 and the curve 3-2 in FIG. 3 is changing the weighting of the temperature. That is, the temperature weighting is increased when the pressure is greater than the threshold value Pk, and the temperature weighting is decreased when the pressure is less than or equal to the threshold value Pk.

  In the correction map of FIG. 3, the pressure region is divided into two regions according to the threshold value Pk. However, if the corresponding correction curve is set by dividing the pressure region into three or more pressure regions, the maintenance time can be obtained more accurately. be able to.

  In this embodiment, the temperature sensor (ambient) 7 is used for temperature detection, but a temperature sensor (main body) 8 may be used. The temperature sensor (main body) 8 is provided on the surface of the compressor main body and the like, and the internal temperature of the compressor main body cannot be detected.

  In this embodiment, the number of the compressor main bodies 2 is one, but a plurality of compressor main bodies may be provided to control the operation.

  According to the present embodiment, since the correction operation time is obtained by changing the weighting of the temperature according to the pressure of the compressed fluid and the maintenance time is calculated, an accurate maintenance time can be obtained. And when a compressor is used with high load, since maintenance time is shortened, failure prevention can be performed reliably. Further, when the compressor is used at a low load, the maintenance time is extended, so that the period until the maintenance is performed is extended, resulting in customer merit.

  The system of the present embodiment will be described with reference to FIGS. The same components as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  FIG. 4 is a block diagram of the compressor in the present embodiment. A change from the first embodiment is that an inverter circuit 11 is provided to control the rotation speed of the motor 3.

  The inverter circuit 11 performs inverter control on the rotation speed of the motor 3 so that the pressure in the air tank 5 detected by the pressure sensor 6 is constant.

  FIG. 5 is a correction map showing an example of the relationship between the rotation speed ratio and the rotation speed maintenance coefficient Kmr, which is a correction coefficient for operation time. Here, the rotation speed ratio is the ratio of the motor rotation speed detected by the inverter circuit 11 to the maximum rotation speed. When the rotational speed is low, the deterioration of the bearing or the like is reduced, and therefore the rotational speed maintenance coefficient increases as the rotational speed ratio decreases.

  In the operation of this embodiment, as in the first embodiment, the control circuit 4 calculates the pressure maintenance coefficient Kmp and the temperature maintenance coefficient Kmt. Further, based on the motor rotation speed detected by the inverter circuit 11, a rotation speed maintenance coefficient Kmr is calculated based on the correction map table or calculation formula shown in FIG.

  In a calculation unit (not shown) in the control circuit, the pressure maintenance coefficient Kmp, the temperature maintenance coefficient Kmt, the rotation speed maintenance coefficient Kmr calculated by the control circuit 4 and the operation time T of the compressor main body 2 are calculated from the following formula 2. The corrected operation time Tm is obtained.

Tm = T × 1 / (Kmp × Kmt × Kmr) (Formula 2)
Similar to the first embodiment, when the accumulated operation time is obtained from the integrated value of the corrected operation time Tm from the start of use of the compressor or from the start of use after maintenance, and the accumulated operation time reaches a preset maintenance set time. A maintenance instruction signal is issued.

  The display 10 displays the accumulated operation time obtained by the control circuit 4 and notifies the user that it is the maintenance time according to the maintenance instruction signal.

  In the inverter-controlled compressor, the number of revolutions of the motor 3 is inverter-controlled so that the pressure in the air tank 5 is constant, but the pressure setting means is provided so that the set pressure can be changed. You may do it.

  According to the present embodiment, in addition to the effects of the first embodiment, in a variable speed compressor equipped with an inverter, it is possible to accurately calculate a maintenance time considering a load change due to a change in compressor rotation speed.

  In this embodiment, the maintenance time is notified to the user without using the display 10 in the compressor of the first or second embodiment.

  The control circuit 4 controls the motor 3 according to the maintenance instruction signal issued from the control circuit 4 to reduce the upper limit pressure of the compressor 1 or the rotational speed of the compressor body 2 to reduce the performance of the product, thereby reducing the maintenance time. Notify the user. Alternatively, the compressor main body 2 may be stopped by a maintenance instruction signal.

  According to the present embodiment, the display 10 for notifying the maintenance execution time described in the first embodiment is not necessary.

  The system of the present embodiment will be described with reference to FIGS.

In this embodiment, the temperature weighting is changed based on the operating rate R ₀ of the compressor body.

FIG. 6 is a diagram showing a driving situation when the compressor is ON-OFF driven. When the compressor is driven for a period of T _ON 1, the fluid pressure gradually rises, and when the upper limit pressure is reached, the compressor stops. Then, the fluid pressure gradually decreases, and when the lower limit pressure is reached, the compressor is driven again for a period of T _ON 2. The compressor repeats this operation. The sum of up to operating time _{T ON 1~T} ON n of the compressor body 2, defined as operating rate _{R 0} of the compressor body 2 divided by the total time _{T 0} (Equation 3).

FIG. 7 is a correction map showing an example of the relationship between the ambient temperature detected by the temperature sensor and the temperature maintenance coefficient Kmt which is a correction coefficient for the operation time. When the temperature of the compressor body rises, it becomes severe operating conditions, and grease and seals used in the compressor body tend to deteriorate. Therefore, a correction coefficient as shown in the figure is used according to the ambient temperature. In addition, this map includes a curve 3 used when the operation rate R ₀ is 0.8 or more, a curve 2 used when the operation rate R ₀ is 0.5 or more, and an operation rate R ₀ of less than 0.5. Curve 1 used in the case. The correction map in FIG. 7 may be obtained in advance by calculation or experiment.

  The correction map of FIG. 7 may be stored in advance in the storage circuit 9 as a table, or may be stored in the storage circuit 9 as a calculation formula.

In the operation of the present embodiment, first, in the block diagram of the compressor of the first embodiment, the control circuit 4 calculates the operating rate R ₀ of the compressor body 2. Curves 1 to 3 having different inflection points of the temperature maintenance coefficient shown in FIG. 7 are selected according to the calculated operation rate R ₀ , and a temperature maintenance coefficient Kmt corresponding to the ambient temperature is obtained.

  Similar to the first embodiment, the corrected operation time Tm is calculated from the calculated temperature maintenance coefficient Kmt, pressure maintenance coefficient Kmp, and operation time T based on Equation 1. The accumulated operation time is obtained from the integrated value of the corrected operation time Tm from the start of use of the compressor or from the start of use after maintenance, and a maintenance instruction signal is issued when the accumulated operation time reaches a preset maintenance set time.

  The display 10 displays the accumulated operation time obtained by the control circuit 4 and notifies the user that it is the maintenance time according to the maintenance instruction signal.

The temperature maintenance coefficient Kmt according to the ambient temperature in FIG. 7 takes a large value (1.0) in a region where the ambient temperature is low, and decreases with increasing temperature from the inflection point. Further, the inflection point varies depending on the operation rate R _0, and a curve 3 that decreases from a low temperature is used when the operation rate is large, and a curve 1 that decreases at a high temperature is used when the operation rate is small. Therefore, from Equation 1, when the ambient temperature is high, correction is performed to increase the operation time, and when the operation rate is high, correction is performed to increase the operation time from a lower ambient temperature. Therefore, the maintenance time is shortened in high-temperature operating conditions where the components of the compressor body are greatly deteriorated, and when the operating rate at which the internal temperature of the compressor body rises is high, the maintenance time is further shortened. Is done. Since the ambient temperature of the compressor is different from the internal temperature, the maintenance time corresponding to the actual internal temperature can be obtained by switching the correction coefficient according to the operating rate.

  Switching the curves 1 to 3 in FIG. 7 is to change the temperature weighting. When the operation rate is large, the temperature weighting is increased, and when the operation rate is small, the temperature weighting is decreased.

In the present embodiment, in addition to the effects of the first embodiment, the maintenance execution time including the operating rate R ₀ that affects the life of the compressor body 2 is changed, so that accurate maintenance time can be calculated. .

  The present embodiment is configured such that in the compressor of the first or second embodiment, the remaining time until the maintenance is performed is estimated and notified to the user. In the control circuit 4, the remaining time until the maintenance can be obtained can be obtained by subtracting the accumulated operation time obtained in the first embodiment from the preset maintenance setting time. The obtained remaining time is displayed on the display 10.

  According to the present embodiment, the remaining time until the maintenance is performed is displayed, so that the remaining operation time can be known, and user convenience is improved.

DESCRIPTION OF SYMBOLS 1 Compressor, 2 Compressor body, 3 Motor, 4 Control circuit, 5 Air tank, 6 Pressure sensor, 7 Temperature sensor (Ambient), 8 Temperature sensor (Compressor body), 9 Memory circuit, 10 Display, 11 Inverter circuit.

Claims (11)

A compressor body for compressing fluid;
A motor for driving the compressor body;
A temperature sensor for detecting the temperature of the compressor;
A pressure sensor for detecting the pressure of the compressed fluid output from the compressor body;
A control circuit,
The control circuit includes:
From the temperature maintenance coefficient Kmt based on the temperature of the compressor, the pressure maintenance coefficient Kmp based on the pressure of the compressed fluid, the rotational speed maintenance coefficient Kmr based on the rotational speed of the motor, and the operating time T of the compressor body The corrected operation time Tm is expressed by the following formula:
Tm = T × 1 / (Kmt × Kmp × Kmr)
Sought by
The accumulated operation time is obtained from the integrated value of the corrected operation time Tm from the start of use of the compressor or from the start of use after maintenance, and a maintenance instruction signal is issued when the accumulated operation time reaches a preset maintenance set time. Compressor characterized by. The compressor according to claim 1 ,
The compressor characterized in that the rotational speed maintenance coefficient Kmr is a small value when the rotational speed of the motor is large, and is a large value when the rotational speed of the motor is small.   The compressor according to claim 1,
  The compressor is characterized in that the temperature maintenance coefficient Kmt takes a large value in a region where the temperature of the compressor is low, decreases as the temperature rises from an inflection point, and is a small value in a region where the temperature is high.   The compressor according to claim 1,
  The compressor is characterized in that the pressure maintenance coefficient Kmp takes a large value in a region where the pressure of the compressed fluid is low, decreases as the pressure increases from an inflection point, and has a small value in a region where the pressure is high. The compressor according to any one of claims 1 to 4 , further comprising:
A compressor comprising a display mechanism for displaying an accumulated operation time calculated by the control circuit . The compressor according to any one of claims 1 to 4 , further comprising:
The control circuit calculates the time until the maintenance of the compressor body,
A compressor comprising a display mechanism for displaying a time until maintenance is performed. In the compressor given in any 1 paragraph of Claims 1-4 ,
When the maintenance execution time calculated by the control circuit is reached, the compressor main body is stopped. The compressor according to claim 1,
A compressor comprising an inverter circuit, wherein the motor is inverter-controlled based on a pressure detected by the pressure sensor. In the compressor given in any 1 paragraph of Claims 1-4 ,
When the maintenance execution time calculated by the control circuit is reached, the rotation speed of the motor is reduced. In the compressor given in any 1 paragraph of Claims 1-4 ,
When the maintenance execution time calculated by the control circuit is reached, the compressor main body is operated by lowering the target pressure of the compressed fluid. In the compressor given in any 1 paragraph of Claims 1-4 ,
A compressor comprising pressure setting means for the compressed fluid, wherein the set pressure can be changed by the pressure setting means.

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