JP2015218655A - Compressed air supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compressed air supply system capable of automatically supplying compressed air to an air compressor immediately after an occurrence of power failure without interruption.SOLUTION: The compressed air supply system comprises: a motor driven type compressor 10 which is driven by getting a power supply from a commercial power source; an engine driven type compressor 20 as an auxiliary power source of compressed air on an occurrence of power failure; a control device 30 which starts up the engine driven type compressor 20; and a battery 40 as a power source of the control device 30. The control device 30 also has: power failure detection means 31 which generates a power failure detection signal when detecting the occurrence of the power failure; and a control section 32 which outputs a start-up signal to the engine driven type compressor 20 when receiving the power failure detection signal. The engine driven type compressor 20 also has an operation control device 21 which initiates a start-up process of an engine when receiving the start-up signal.

Description

  The present invention relates to a compressed air supply system, for example, a compressed air supply system that supplies compressed air to pneumatic equipment used in factory facilities and the like.

  In order to drive various devices and tools, or to carry products, paint, air blow, etc., factory facilities require a large amount of compressed air when manufacturing products. Supply of compressed air to machines, appliances, and devices that need to be supplied (collectively referred to as “pneumatic equipment” in this specification) by a compressed air supply system provided in factory facilities, etc. It is also managed to.

  In addition, in such factory facilities, etc., in response to fluctuations in the total amount of compressed air consumed depending on the operating state of the pneumatic equipment, it is possible to cope with fluctuations in the compressed air consumption consumed by the pneumatic equipment. In order to supply the required amount of compressed air stably and economically when needed, a compressed air supply system equipped with multiple motor-driven compressors is constructed to reduce the amount of compressed air used. It has also been proposed to perform an operation control method such as a corresponding number control operation or an alternate operation (see Patent Document 1).

  Even when the power supply to the motor-driven compressor is stopped, the motor-driven compressor is automatically re-installed when the power supply stop is “instantaneous stop” that stops within a predetermined short time. There has also been proposed an automatic restart device for an instantaneous power failure of a compressor that starts (see Patent Document 2).

JP 2008-133781 A JP-A-62-1113877

  Some of the factory equipment will be finished for the reason of the manufacturing method of the product being manufactured, or from the viewpoint of quality maintenance, until the predetermined manufacturing process is completed, or processing of the product in lot units, etc. In some cases, the operation cannot be stopped, and in order to maintain the operation of such equipment, it is necessary to ensure the continuous supply of compressed air to the above-described pneumatic equipment.

  However, in a compressed air supply system installed in factory facilities, etc., it is common to use a motor-driven compressor that is operated by receiving power from a commercial power source as a source of compressed air. If the supply of power is interrupted due to the occurrence of a motor, the motor-driven compressor stops and the compressed air cannot be supplied to the pneumatic equipment, and processing is interrupted during the prescribed manufacturing process or in the middle of a lot. Products may require disposal or reworking due to manufacturing methods or quality control reasons, resulting in significant losses.

  Therefore, even when a power failure occurs, it is desired to maintain the operation of the compressed air supply system and ensure the supply of compressed air continuously.

  As a countermeasure against such a power failure, for example, as shown in FIG. 5, the above-described compressed air supply system 100 is provided with an engine-driven generator 170 as a standby power source, and a power failure detection control device 131 provided in the automatic power supply switching device 130. When the engine detects the occurrence of a power failure, the engine-driven generator 170 is started, and the automatic power switching means 132 supplies the electric power generated by the engine-driven generator 170 to the motor-driven compressor 110 to provide a motor-driven type. It is also conceivable to operate the compressor 110.

  However, the power consumption of the compressed air supply system is so large that it is generally said that it corresponds to 30% of the total power consumption of the factory equipment, and the three types used in the motor-driven compressor 110. Phase AC motors require about three times as much power when starting as compared to rated operation.

  For this reason, when the engine-driven generator 170 is used as a standby power source and power is supplied to the motor-driven compressor 110 of the compressed air supply system 100 by the engine-driven generator 170 in the event of a power failure, it is usually used. As a reserve power source used only in the event of a power failure, it is necessary to always have an expensive large-sized engine-driven generator 170, which requires a large initial investment, and such a large-sized engine drive. It is necessary to secure the space for installing the type generator 170 and to pay for the maintenance and management and the burden of labor.

  Even if the above problem is cleared and a large engine-driven generator 170 is installed as a backup power source, the engine-driven generator 170 as a backup power source starts up to a predetermined voltage after a power failure occurs. Since a predetermined time is required until stable power supply can be started, power supply to the motor-driven compressor 110 is cut off during that time.

  In addition, when the motor-driven compressor 110 is restarted upon receiving power from the standby power supply, the discharge-side pressure rises to a predetermined pressure and stable supply of compressed air can be resumed. However, a predetermined time is required, and as a result, it takes a relatively long time from the occurrence of a power failure until the supply of compressed air is resumed. During this time, the pneumatic device 160 stops.

  In particular, in order to restart the motor-driven compressor 110 that has been stopped after the supply of power has been stopped, a complicated operation such as manually operating switches provided on the operation panel or the like of the motor-driven compressor 110 is required. If necessary, the time required from restarting the supply of compressed air after the occurrence of a power failure is further increased.

  As introduced in Patent Document 2, even if the power supply to the motor-driven compressor is stopped, if the power supply stop is “instantaneous stop”, the motor-driven compressor is Since a restart device for a compressor that can be automatically started has been proposed, the restart device is a compressed air supply system 100 provided with the engine-driven generator 170 of FIG. 5 as a backup power source. It is also conceivable that the motor-driven compressor 110 can be automatically restarted when power supply from the standby power supply is started within a certain time after the occurrence of a power failure.

  However, even if the motor-driven compressor 110 can be automatically restarted, the motor-driven compressor 110 is stopped until power supply from the standby power supply is started after a power failure occurs. Therefore, after the motor-driven compressor 110 is stopped, the compressed air supply to the pneumatic device 160 is stopped until the compressed air can be stably supplied after the motor-driven compressor 110 is restarted. Is unchanged.

  Moreover, if the time from the occurrence of a power failure to the start of power supply by the standby power source exceeds the “instantaneous power outage” for a long time, the restart cannot be performed automatically.

  In the compressed air supply system 100, when the pneumatic device 160 is stopped and the compressed air is not consumed, the motor driven compressor 110 is stopped, and the pneumatic device 160 is started to consume the compressed air. When the operation is resumed, the motor-driven compressor 110 is restarted to resume the supply of compressed air. Therefore, after the pneumatic device 160 resumes operation, the motor-driven compressor 110 is stopped. During the period from the start to the full load operation, the supply of compressed air is insufficient, and the pressure of the compressed air supplied to the pneumatic device 160 temporarily decreases.

  Therefore, even when such a pressure drop of compressed air occurs, the pressure of the compressed air supplied to the pneumatic device 160 is required to maintain a predetermined pressure (for example, operation of the pneumatic device). As shown in FIG. 5, the collecting tank 153 is provided in the supply piping system 150 that connects the motor-driven compressor 110 and the pneumatic device 160 so that the pressure does not drop below the minimum operating pressure of the pneumatic device. Even if the consumption of compressed air by the pneumatic device 160 is resumed by increasing the storage volume of the supply piping system 150 including the collecting tank 153, the pressure in the supply piping system 150 is not reduced to a predetermined value. It does not drop below the pressure (minimum operating pressure of pneumatic equipment).

  Therefore, as the above-described collective tank 153 provided in the compressed air supply system 100, after the occurrence of a power failure, the supply of power from the standby power supply is started and the motor-driven compressor 110 is restarted until the full load operation is started. In the meantime, if a large capacity capable of maintaining the supply of compressed air to the pneumatic equipment 160 is provided, the operation of the factory equipment and the like can be continued without stopping the pneumatic equipment 160 even in the event of a power failure. It becomes possible.

  However, after the power failure occurs, until the engine-driven generator 170 can be started and stable power supply can be started, the subsequent restart of the motor-driven compressor and stable compressed air supply are performed. If a collective tank 153 having a capacity sufficient to supply compressed air to the pneumatic equipment 160 is provided for a relatively long time before restarting, a large collective tank 153 corresponding to the scale of the equipment is provided. Installation of the compressed air supply system 100 is incurred, and the installation space for installing the large collective tank 153 is also required.

  Therefore, the present invention has been made to solve the above-described drawbacks of the prior art, and can supply compressed air to pneumatic equipment automatically and quickly without interruption when a power failure occurs. An object of the present invention is to provide a compressed air supply system that can be used.

  Hereinafter, means for solving the problem will be described together with reference numerals used in the embodiment for carrying out the invention. This code is used to clarify the correspondence between the description of the scope of claims and the description of the mode for carrying out the invention. Needless to say, it is used in a limited manner for the interpretation of the technical scope of the present invention. It is not a thing.

In order to achieve the above object, the compressed air supply system 1 of the present invention comprises:
In a compressed air supply system 1 including a motor-driven compressor 10 driven by power supplied from a commercial power supply as a compressed air supply source,
An engine driven compressor 20 is provided as a preliminary supply source of compressed air at the time of a power failure, a control device 30 for controlling the start of the engine driven compressor 20 and a battery 40 as a power source for the control device 30 are provided.
In the control device 30,
A power failure detection means 31 for detecting stoppage of power transmission from the commercial power source;
A control unit 32 that outputs a start signal to the engine-driven compressor 20 on condition that a power failure detection signal is received from the power failure detection means 31 is provided.
The engine drive type compressor 20 is provided with an operation control device 21 that starts the engine start process of the engine drive type compressor 20 on condition that a start signal is received from the control unit 32 ( Claim 1).

  In the compressed air supply system 1 having the above-described configuration, a charger 33 that charges the battery 40 with electric power supplied from the commercial power supply can be further provided, for example, in the control device 30 (Claim 2).

Furthermore, pressure detecting means Ps2 for detecting the pressure of the compressed air supplied to the pneumatic device 60 is provided,
The control unit 32 of the control device 30 receives a power failure detection signal from the power failure detection means 31, and further, the pressure detection means Ps2 is equal to or lower than a predetermined starting pressure (for example, full load operation return pressure PL). The start signal may be output on condition that the pressure is detected (claim 3).

In addition, the power failure detection means 31 of the control device 30 is configured to be able to output a power recovery detection signal by detecting the resumption of power supply from the commercial power source,
The control unit 32 is configured to output a stop signal to the engine-driven compressor on condition that the power recovery detection signal is received from the power failure detection unit 31;
The operation control device 21 of the engine-driven compressor 20 may start engine stop processing of the engine-driven compressor on the condition that the stop signal is received (claim 4).

In this case, pressure detection means Ps2 for detecting the pressure of the compressed air supplied to the pneumatic device 60 is provided,
In addition to receiving the power recovery detection signal from the power failure detection means 31, the control unit 32 of the control device 30 further has the pressure detection means Ps2 equal to or higher than a predetermined stop pressure (for example, no-load operation start pressure PH). The stop signal may be output on condition that the pressure is detected.

  According to the configuration of the present invention described above, according to the compressed air supply system 1 of the present invention, the following remarkable effects can be obtained.

  When the operation of the motor-driven compressor 10 is stopped due to a power failure, the engine-driven compressor 20 provided as a preliminary supply source of compressed air is automatically and quickly started and the compressed air is supplied to the pneumatic device 60. Can be provided.

  As a result, even if a power failure occurs, the supply of compressed air is continued without stopping the supply of compressed air to the pneumatic equipment 60 and with the pressure drop of the supplied compressed air minimized. We were able to.

  In addition, after the motor-driven compressor 10 is stopped, the engine-driven compressor 20 is quickly started to take over the supply of compressed air. Therefore, after the occurrence of a power failure, the engine-driven compressor 20 takes over. Even if the capacity of the supply piping system 50, specifically, the capacity of the collective tank 53 is reduced, the decrease in the supply pressure that occurs during the process can be suppressed to a relatively low level. The pressure of the compressed air to be supplied can be suitably prevented from dropping below a predetermined pressure (minimum operating pressure) required for the operation of the pneumatic device 60, and the introduction cost of the compressed air supply system can be reduced. In addition, the installation area can be reduced.

  In addition, the motor drive compressor 10 provided as a main supply source of compressed air is not driven by electric power from an engine drive generator as a reserve power supply, but is driven by an engine drive provided as a reserve supply source of compressed air. By adopting a configuration that takes over the supply of compressed air by the mold compressor 20 and incorporating a battery 40 as a power source for the control device 30, it is not necessary to provide an engine-driven generator as a reserve power source, Sometimes it is not necessary to supply any power from outside.

  As a result, it was possible to exclude the compressed air supply system from the power supply target of the standby power supply provided in the factory facilities, etc., and the standby power supply could be greatly downsized.

  Note that pressure detection means Ps2 for detecting the pressure of the compressed air supplied to the pneumatic device 60 is provided, and after receiving the power failure detection signal, the pressure detection means Ps2 has a predetermined pressure (for example, full load operation return pressure PL). When the control unit 32 of the control device 30 outputs a start signal when the following pressure is detected, the engine is stopped when the pneumatic device 60 is stopped and compressed air is not consumed. It was possible to prevent the drive compressor 20 from being started in vain.

  Further, after receiving the power recovery detection signal, the control unit 32 of the control device 30 outputs a stop signal when the pressure detection means Ps2 detects a pressure equal to or higher than a predetermined pressure (for example, no-load operation start pressure PH). In this case, the operation of the engine-driven compressor 20 is continued until the restarted motor-driven compressor 10 is in a state where stable supply of compressed air can be performed. Thus, the pressure of the compressed air supplied in this way can be prevented from dropping below a predetermined pressure, for example, the minimum operating pressure of the pneumatic device 60.

The block diagram of the compressed air supply system of this invention. The block diagram of another compressed air supply system of this invention. Engine driven compressor time chart. The time chart of the engine starting process of an engine drive type compressor. The block diagram of the compressed air supply system provided with the reserve power supply.

  The compressed air supply system 1 of the present invention will be described below with reference to the accompanying drawings.

〔overall structure〕
In FIG. 1, reference numeral 1 denotes a compressed air supply system according to the present invention. This compressed air supply system 1 is used as a compressed air supply source (main supply source) during normal operation and is driven by electric power from a commercial power source. A motor-driven compressor 10 that is used, and an engine-driven compressor 20 that is used as a compressed air supply source (preliminary supply source) and is driven by a built-in engine (not shown) in the event of a power failure. A control device 30 that controls the start of the engine-driven compressor 20 and a battery 40 that is a power source of the control device 30 at the time of a power failure. When a power failure occurs and the motor-driven compressor 10 stops, The apparatus 30 is configured to automatically supply the compressed air by automatically starting the engine-driven compressor 20.

  The compressed air supply system 1 is provided with a supply piping system 50 for supplying compressed air generated by the motor-driven compressor 10 and the engine-driven compressor 20 to the pneumatic equipment 60. In the illustrated embodiment, the discharge pipe 51 communicated with the motor-driven compressor 10 and the discharge pipe 52 communicated with the engine-driven compressor 20 are both communicated with the collective tank 53 so as to be within the collective tank 53. The compressed air can be stored in the air tank 60, and the compressed air can be supplied to the pneumatic equipment 60 via the supply pipe 54 communicating with the collecting tank 53. The discharge pipe 51, 52, the collect tank 53, and the supply pipe 54 constitute the supply pipe system 50 described above.

  In the illustrated embodiment, an engine (not shown) starting battery 40 mounted on the engine-driven compressor 20 is also used as a power source for the control device 30. The battery 40 for the engine may be provided in the control device 30, for example, separately from the battery for starting the engine of the engine-driven compressor 20, or the control device 30 without providing the battery in the engine-driven compressor 20 You may comprise so that the engine of the engine drive type compressor 20 may be started with the battery provided in the inside.

[Motor driven compressor]
The motor-driven compressor 10 is used as a compressed air supply source (main supply source) during normal operation in which power is supplied from a commercial power source, and is driven by power supplied from the commercial power source. And a compressor main body (not shown) driven by the motor 11, and the compressor main body driven by the motor 11 sucks outside air and compresses and discharges it to supply compressed air. It is configured to be able to do.

  As such a motor-driven compressor 10, those of various known configurations can be used.

  In the present embodiment, a known oil-cooled motor-driven compressor is adopted as the motor-driven compressor 10, and the compressor having this configuration is used for lubrication, sealing, and cooling of the compressor body. The compressor body is discharged as a gas-liquid mixed fluid because it is discharged as a gas-liquid mixed fluid between the cooling oil introduced into the compression working space and the compressed air that compresses the sucked outside air. A receiver tank 12 is provided for storing the compressed fluid and separating it into cooling oil and compressed air.

  Then, the compressed air from which the cooling oil is separated in the receiver tank 12 is supplied to the pneumatic device 60 through the discharge pipe 51, the collecting tank 53, and the supply pipe 54 described above.

  The motor-driven compressor 10 is provided with a capacity control device 13 that performs known capacity control so that compressed air can be always supplied to the pneumatic equipment 60 side at a pressure within a certain range. The capacity control device 13 performs opening / closing control of an intake valve (not shown) of the compressor main body and / or rotation speed control of the motor 11, whereby a pressure detection means (Ps3) constituted by a pressure sensor or the like. Is a predetermined full-load operation return pressure in which the discharge-side pressure (pressure in the receiver tank 12 in the illustrated example) detected by the compressor is set higher than the minimum operating pressure (P1) of the pneumatic device 60. (PL) and a capacity control so as to be maintained at a pressure between a predetermined load-less operation start pressure (PH) set to a pressure higher than the full-load operation return pressure (PL). Yes.

  In the illustrated embodiment, the discharge-side pressure of the motor-driven compressor 10 is obtained by measuring the pressure in the receiver tank 12. The pressure detection is not limited to the configuration obtained by measuring the pressure in the receiver tank 12, but is detected in the supply piping system 50 from the motor-driven compressor 10 to the pneumatic device 60, for example, the discharge piping 51, the collect tank 53, and the supply piping 54. It is good also as what detects by providing a means.

  In the configuration shown in FIG. 1, on the basis of the detection signal from the pressure detection means (Ps3), the opening / closing control of the intake port of the compressor body is performed based on the control signal output from the capacity control device 13 which is the electronic control means. The motor 11 is configured to electrically control the rotational speed control of the motor 11, but instead of such electrical control, for example, a known machine that uses regulators that are operated by the discharge side pressure of the compressor body, for example. The above-described capacity control may be performed by general control.

  As described above, when the capacity control device 13 is constituted by an electronic control device, the capacity control device 13 may be provided with a function of a protection circuit for the motor-driven compressor 10, and the motor-driven compressor When 10 is in an operating state corresponding to a preset alarm or emergency stop condition, a warning or the like is displayed by a liquid crystal monitor panel or an indicator lamp provided on an operation panel (not shown) of the motor driven compressor 10. In addition, the motor-driven compressor 10 may be configured to perform an emergency stop when an emergency stop condition is met.

  Examples of such alarm display or emergency stop conditions for the motor-driven compressor 10 include a decrease in the amount of lubricating oil in the compressor body, an increase in the oil temperature of the lubricating oil, filter clogging, and overload. .

[Engine driven compressor]
The engine-driven compressor 20 is used as a compressed air supply source (preliminary supply source) in the event of a power failure, and is a diesel engine (not shown) so that it can operate independently without power supply. ), A compressor body (not shown) driven by the engine, a starter 23 for starting the engine, and an operation control device 21 for controlling the operation of the engine-driven compressor 20. The compressor main body driven by the engine sucks outside air and compresses / discharges it, so that the pneumatic device 60 can be used in place of the motor-driven compressor 10 in the event of a power failure when the supply of commercial power is cut off. Compressed air can be supplied.

  As such an engine-driven compressor 20, various types of known configurations can be used. For example, components necessary for operating independently, such as an engine, a fuel tank, a compressor body, a battery, A known engine-driven compressor called a “package type” in which a starter, various control devices, etc. are housed in a bonnet may be used.

  In the present embodiment, like the motor-driven compressor 10 described above, an oil-cooled type is used as the engine-driven compressor 20, and therefore the engine-driven compressor 20 is connected to the cooling oil. A receiver tank 22 for introducing compressed air discharged as a gas-liquid mixed fluid and separating cooling oil is provided.

  In addition, the pressure in the receiver tank 22 is set so that the engine-driven compressor 20 can supply compressed air at a constant pressure to the consumption side. ) And the no-load operation start pressure (PH).

  In the present embodiment, the operation control device 21 that controls the operation of the engine-driven compressor 20 is provided with an intake port of the compressor body in accordance with the start / stop operation of the engine and the pressure in the receiver tank 22. It has a function as a capacity control device that performs open / close control and / or increase / decrease in engine speed, but the capacity control device may be based on known mechanical control using, for example, a regulator or various sensors. It is possible to use a method such as a method using electronic control using the above or a combination of the electronic control and the mechanical control.

  The above-described operation control device 21 provided in the engine-driven compressor 20 receives a start signal from the control device 30 to be described later, starts the engine-driven compressor 20 according to a predetermined procedure, and also drives the engine-driven compressor. The operating state of the compressor 20 is a power generation signal of an alternator (generator) installed in the engine, a detection signal of a hydraulic pressure detection means for detecting engine hydraulic pressure, a rotational speed detection means for detecting the rotational speed of the engine, and a discharge of the compressor body. Monitoring is performed based on a detection signal from the pressure detection means Ps1 or the like that detects the side pressure, and the result is output to the control device 30 described later.

  Further, when the control unit 32 of the control device 30 to be described later outputs a stop signal, the operation control device 21 receives this stop signal and stops the engine-driven compressor 20 according to a predetermined procedure. good.

  The output from the operation control device 21 to the control device 30 includes an “engine operation signal” indicating that the engine has reached a predetermined rotation speed, and the discharge side pressure of the compressor body is a predetermined pressure (for example, 0 In addition to a “pressure establishment signal” indicating that the pressure exceeds 15 MPa, an “alarm signal” and an “emergency stop signal” indicating an abnormality in the engine-driven compressor are output.

  The operation control device 21 may have a function of a protection circuit that causes the engine-driven compressor to perform an emergency stop when the “alarm signal” and the “emergency stop signal” are output. When the operating state corresponding to the output conditions of the alarm signal and emergency stop signal described above is reached by monitoring the operating state, the alarm signal and emergency stop signal are output to the control unit 32 of the control device 30, and the engine driven compressor 20 may be configured to perform an emergency stop control.

  Such alarm or emergency stop conditions include, for example, a decrease in the oil pressure of the engine lubricating oil provided in the engine-driven compressor 20, a decrease in the oil amount of the lubricating oil, an increase in the oil temperature of the lubricating oil, There are an increase in cooling water temperature, a decrease in engine rotation speed, a shortage of fuel (gas shortage), a decrease in the amount of lubricating oil in the compressor body, an increase in the oil temperature of the lubricating oil, and the like.

  The engine-driven compressor 20 is provided with an instrument panel (not shown) provided with a key switch and the like for starting and stopping the engine-driven compressor 20. Regardless of the presence or absence of a start signal from the control unit 32, the operation control device may be configured to start the engine-driven compressor by operating the key switch.

〔Control device〕
The aforementioned control device 30 receives a power failure detection means 31 for detecting a power failure of the commercial power supply, and a power failure detection signal from the power failure detection means 31 and sends a start signal to the operation control device 21 of the engine-driven compressor 20. In addition to the output, the monitoring result (the aforementioned “engine operation signal”, “pressure establishment signal”, “alarm signal”, “emergency stop signal”) regarding the operation state of the engine-driven compressor 20 received from the operation control device 21 Based on this, a control unit 32 is provided for causing the display means 34 such as a liquid crystal display to display the operating state of the engine-driven compressor, alarms, and the like.

  In FIG. 1, only the power failure detection signal is displayed as the output signal of the power failure detection means 31, but the power failure detection means 31 detects the resumption of power supply by the commercial power source (hereinafter referred to as “recovery”). In this case, the control unit 32 that has received the power recovery detection signal from the power failure detection means 31 can provide the operation control device 21 of the engine driven compressor 20 with the power recovery detection signal. On the other hand, a stop signal for instructing to stop the engine-driven compressor 20 may be output.

  In addition, the control device 30 includes a charger 33 that charges a battery 40 serving as a power source for the control device 30 with power supplied from a commercial power source.

  In the embodiment shown in FIG. 1, the engine starting battery 40 mounted on the engine driven compressor 20 is also used as the power source battery of the control device 30, so that when the power is supplied from the commercial power source, The battery 40 is charged, and at the time of a power failure, charging can be performed by an alternator (not shown) provided in the engine-driven compressor 20.

  However, the battery for the control device 30 may be provided in the control device 30, for example, separately from the battery provided in the engine-driven compressor 20, and the battery is not mounted in the engine-driven compressor 20. In addition, a battery mounted on the control device 30 may be used for starting the engine of the engine-driven compressor.

[Other configurations]
As shown in FIG. 2, there is provided pressure detection means Ps2 for detecting the pressure of compressed air supplied to the pneumatic equipment 60, for example, the pressure in the supply piping system 50, in the illustrated example, the pressure in the collective tank 53. The control unit 32 of the control device 30 monitors the pressure of the compressed air supplied to the pneumatic device 60 by the detection signal of the pressure detection means Ps2, and detects a power failure detection signal or power recovery detection from the power failure detection means 31. Even when the signal is received, the start signal or the stop signal may not be output if the pressure of the compressed air supplied to the pneumatic device 60 is not in a predetermined pressure state.

  Specifically, even when the control unit 32 receives the power failure detection signal, the pressure detected by the pressure detection means (Ps2) exceeds, for example, the full load operation return pressure (PL) of the motor driven compressor 10. Is configured such that the start signal is not output and the start signal is output when the pressure falls below the full load operation return pressure (PL), for example, the pneumatic device 60 is stopped and the compressed air is consumed. It is possible to prevent the engine-driven compressor from being started in vain when the engine is not in operation.

  Further, even when the control unit 32 receives the power recovery detection signal, the stop signal is detected when the pressure detected by the pressure detection means (Ps2) is less than the no-load operation start pressure (PH) of the motor-driven compressor 10, for example. Is not output, the operation of the engine-driven compressor 20 is continued, and the supply of compressed air by the restarted motor-driven compressor 10 is stabilized and becomes a stop signal when the pressure exceeds the no-load operation start pressure (PH). Is output to stop the engine-driven compressor 20, so that the shortage of compressed air supplied by the motor-driven compressor 10 that is in an unstable operation state immediately after the restart is detected by the compressed air from the engine-driven compressor 20. You may comprise so that it can supplement by supply.

  Although not shown, a control room for controlling and monitoring the operation of the entire compressed air supply system 1 may be provided so that a signal relating to the operating status of the compressed air supply system can be output to the control room. .

[Operation etc.]
(1) During normal operation The compressed air supply system 1 of the present invention configured as described above receives power supplied from the commercial power source during normal operation when power is supplied from the commercial power source. Compressed air generated in the motor-driven compressor 10 to be operated is supplied to the pneumatic device 60 through the discharge pipe 51, the collecting tank 53, and the supply pipe 54 that constitute the supply pipe system 50.

  The capacity control device 13 of the motor driven compressor 10 is configured so that the discharge side pressure (pressure in the receiver tank 12) of the compressor body is based on the detection signal of the pressure detection means Ps3 and the full load operation return pressure (PL) described above. The operation of each part is controlled by the capacity control means 13 so as to control opening and closing of the intake port of the compressor body and to control the rotation speed of the motor 11 so as to be held during the no-load operation start pressure (PH). .

  Specifically, when the pressure detected by the pressure detection means (Ps3) is lower than the full load operation return pressure (PL), the capacity control device 13 opens the compressor main body and opens the motor 11 When full load operation is performed with the rotation speed at the full load rotation speed (maximum rotation speed) and the detected pressure of the pressure detection means (Ps3) becomes equal to or higher than the full load operation return pressure (PL), Open / close control and increase / decrease control of motor rotation speed are performed.

  In the normal operation in which power is supplied from the commercial power source and compressed air is supplied from the motor-driven compressor 10 as described above, the control device 30 charges the battery 40 with the charger 33. The power failure detection means 31 does not output the power failure detection signal and the start signal from the control unit 32 is not output, so the engine drive compressor 20 is in a stopped state.

(2) During a power failure As described above, during a power failure when the power supply from the commercial power supply is stopped, the motor-driven compressor 10 is no longer supplied with power. Stop.

  On the other hand, the power failure detection means 31 provided in the control device 30 detects the occurrence of a power failure at the commercial power source and outputs a power failure detection signal to the control unit 32 (T1 in FIG. 3).

  The control unit 32 that has received the power failure detection signal from the power failure detection means 31 outputs a start signal for instructing the engine start to the operation control device 21 provided in the engine-driven compressor (T2 in FIG. 3). .

  The output of the start signal by the control unit 32 may be performed immediately after receiving the power failure detection signal from the power failure detection means 31, but it may be caused by a momentary power failure (instant power failure) due to lightning or an unexpected voltage fluctuation of the power source. In order to prevent malfunction of the engine driven compressor 20, the power failure detection means 31 detects a power failure and outputs a start signal to the engine driven compressor after the power failure state continues for a predetermined time (2 seconds as an example). A confirmation function may be provided (T1-T2 in FIG. 3).

  Further, in the configuration shown in FIG. 2 in which the control unit 32 of the control device 30 is configured to monitor the pressure of the compressed air supplied to the pneumatic device 60 by the pressure detection means Ps2, after the power failure detection signal is received, , When the pressure detected by the pressure detecting means Ps2 falls below a predetermined pressure set in advance, for example, below the full load operation return pressure (PL), the above start signal may be output. With this configuration, it is possible to prevent the engine-driven compressor 20 from being unnecessarily started in a stopped state of the pneumatic device 60 in which compressed air is not consumed.

  In this way, when the control unit 32 of the control device 30 outputs a start signal, the operation control device 21 that has received the start signal performs a start process of the engine-driven compressor 20 according to a predetermined procedure.

  In the present embodiment in which a diesel engine is mounted on the engine-driven compressor 20, the operation control device 21 is connected to preheating means (glow plug, air heater, etc .: not shown) provided in the engine for a predetermined time (as an example). 5 seconds) Energizing the battery power supply to preheat the engine, the starter 23 is started (cranking) and the engine is started (T2-T3 in FIG. 3).

  During engine start-up operation, the operation control unit 21 generates a power generation signal of an alternator (generator) mounted on the engine, a detection signal of a hydraulic pressure detection means for detecting the hydraulic pressure of the engine, and a rotational speed detection means for detecting the rotational speed of the engine. The engine rotation speed is monitored based on the detection signal from the engine, and when the engine reaches a predetermined rotation speed, an engine operation signal is output to the control unit 32 of the control device 30 (T4 in FIG. 3). The control unit 32 that has received the operation signal stops outputting the start signal.

  The operation control device 21 is configured to start (crank) the starter 23 until the engine starts and reaches a predetermined rotational speed while receiving the start signal from the control unit 32. In the embodiment, as shown in FIG. 4, the control unit 32 of the control device 30 operates the operation control device even if a predetermined time (for example, 10 seconds) elapses after the engine starts cranking by the output of the start signal. When the engine operation signal from the engine 21 cannot be received, the output of the start signal is temporarily stopped, and after waiting for a predetermined time (for example, 15 seconds), the start signal is output again, and the output of such a start signal is If the engine operation signal cannot be received even after repeating three times, the control unit 32 of the control device 30 determines that the engine-driven compressor 20 has fallen into start-up congestion, and starts the start-up congestion with respect to the display means 34 described above. It is configured so as to perform the display of a certain effect.

  Thereafter, the engine-driven compressor 20 is subjected to operation control by a capacity control device realized by the operation control device 21, and the pressure in the receiver tank 22 is changed to the full-load operation return pressure (PL) of the motor-driven compressor 10. The intake port of the compressor body is controlled to be opened and closed so as to be maintained between the engine start pressure (PH) and the no-load operation start pressure (PH), and the rotational speed of the engine is controlled. , Compressed air having a predetermined pressure similar to that during normal operation is continuously supplied to the pneumatic device 60.

  Further, the operation control device 21 includes a pressure switch, a pressure sensor, and the like for the discharge side pressure of the compressor body provided in the engine-driven compressor 20, or the pressure in the receiver tank 22 in the illustrated embodiment. Monitoring is performed based on the detection signal of the pressure detection means Ps1, and when the discharge side pressure of the compressor body exceeds a preset pressure (0.15 MPa as an example), a “pressure establishment signal” is transmitted to the control unit ( T5 in FIG. 3).

  Furthermore, when the operation control device 21 is provided with a function of a protection circuit, the operation control device 21 reduces the oil pressure of the engine lubricating oil provided in the engine-driven compressor 20 and the oil amount of the lubricating oil. , Increase in the temperature of the lubricating oil, increase in the coolant temperature of the engine, decrease in engine speed, insufficient fuel (gas shortage), decrease in the amount of lubricating oil in the compressor body, increase in the temperature of the lubricating oil And the like, and an alarm signal and an emergency stop signal are output to the control unit 32 of the control device 30 based on the monitoring result (after T6 in FIG. 6).

  It should be noted that the operation state remains until a predetermined time (for example, 10 seconds; T4-T6 in FIG. 3) elapses after the engine of the engine-driven compressor 20 is started and until the engine rotation rises and stabilizes. In the present embodiment, in view of the possibility that the above-described protection circuit may malfunction when monitoring the operating state of the engine-driven compressor 20 in this state and performing an alarm display or emergency stop. In this case, after a predetermined time (10 seconds as an example) has elapsed after the output of the engine operation signal, the operation control device 21 forms a protection circuit (T6 in FIG. 3).

(3) At power recovery When the commercial power supply recovers from the power failure state in which compressed air is supplied by the engine-driven compressor 20 as described above, the supply of power to the motor-driven compressor 10 is resumed. Then, the motor driven compressor 10 is restarted.

  On the other hand, the power failure detection means 31 that has detected the power recovery of the commercial power supply outputs a power recovery detection signal to the control unit 32 (T7 in FIG. 3). A stop signal is output to the operation control device 21 of the mold compressor 20 (T8 in FIG. 3).

  The stop signal may be output immediately upon receipt of the power recovery detection signal from the power failure detection means 31. However, the engine-driven compressor 20 is used until the voltage of the commercial power source is stabilized at the time of power recovery. In order to continue the operation, even if the power failure detection means 31 detects a power recovery, after the power supply voltage is stabilized and a predetermined time (between T7 and T8 in FIG. A confirmation function for outputting a stop signal to the machine 20 may be provided.

  Further, in the configuration shown in FIG. 2 in which the control unit 32 of the control device 30 monitors the pressure of the compressed air supplied to the pneumatic device 60 by the pressure detection unit Ps2, the control unit 32 includes the power failure detection unit. After receiving the power recovery detection signal from 31, when the pressure detection means Ps2 detects that the pressure has reached a preset stop pressure, for example, the no-load operation start pressure (PH) of the motor-driven compressor. The motor-driven compressor 20 may be configured to output a stop signal to the engine-driven compressor 20, and in this configuration, the motor-driven compressor is in a state where sufficient compressed air cannot be supplied immediately after restarting. The supply of compressed air by the compressor may be supplemented by the supply of compressed air from the engine driven compressor.

  In this way, when the control unit 32 outputs a stop signal (T8 in FIG. 3), the operation control device 21 of the engine-driven compressor 20 that has received the stop signal from the control unit 32 performs an engine process according to a predetermined processing procedure. A stop process of the drive compressor 20 is performed.

  As an example, in the present embodiment, the operation control device 21 that has received the stop signal closes the intake port of the compressor main body and performs no-load operation in which the engine rotation speed is reduced to the no-load rotation speed for a predetermined time ( After the cooling operation performed between T8 and T9 in FIG. 3 (60 seconds as an example), the engine is stopped (T9 in FIG. 3), and the engine-driven compressor 20 is stopped (T10 in FIG. 3). The motor-driven compressor 10 shifts to a normal operation in which compressed air is supplied.

1 Compressed air supply system 10 Motor driven compressor 11 Motor 12 Receiver tank (of motor driven compressor)
DESCRIPTION OF SYMBOLS 13 Capacity control apparatus 20 Engine drive type compressor 21 Operation control apparatus 22 Receiver tank 23 Starter 30 Control apparatus 31 Power failure detection means 32 Control part 33 Charger 34 Display means 40 Battery 50 Supply piping system 51 Discharge piping (motor drive type compressor) side)
52 Discharge piping (engine driven compressor side)
53 Collecting tank 54 Supply piping 60 Pneumatic equipment Ps1, Ps2, Ps3 Pressure detection means 100 Compressed air supply system 110 Motor driven compressor 130 Automatic power supply switching device 131 Power failure detection control device 132 Automatic power supply switching device 150 Supply piping system 151 Discharge Piping 153 Collecting tank 154 Supply piping 160 Pneumatic equipment Ps4 Pressure detection means

Claims (5)

In a compressed air supply system comprising a motor-driven compressor driven by power supplied from a commercial power source as a compressed air supply source,
An engine driven compressor is provided as a preliminary supply source of compressed air at the time of a power failure, a control device for controlling the start of the engine driven compressor, and a battery as a power source for the control device are provided,
In the control device,
A power failure detection means for detecting stoppage of power transmission from the commercial power source;
Provided with a control unit that outputs a start signal to the engine-driven compressor on condition that a power failure detection signal is received from the power failure detection means,
A compressed air supply system, wherein the engine drive type compressor is provided with an operation control device for starting the engine start process of the engine drive type compressor on condition that a start signal is received from the control unit.   The compressed air supply system according to claim 1, further comprising a charger that charges the battery with electric power supplied from the commercial power source. In addition to providing pressure detection means for detecting the pressure of compressed air supplied to pneumatic equipment,
In addition to receiving the power failure detection signal from the power failure detection means, the control unit of the control device further outputs the start signal on condition that the pressure detection means detects a pressure equal to or lower than a predetermined start pressure. The compressed air supply system according to claim 1 or 2. The power failure detection means of the control device is configured to detect a resumption of power supply from the commercial power supply and output a power recovery detection signal,
The controller is configured to output a stop signal to the engine-driven compressor on condition that the power failure detection means receives the power recovery detection signal.
The compression according to any one of claims 1 to 3, wherein the operation control device of the engine-driven compressor starts a stop process of the engine-driven compressor on condition that the stop signal is received. Air supply system. In addition to providing pressure detection means for detecting the pressure of compressed air supplied to pneumatic equipment,
In addition to receiving a power recovery detection signal from the power failure detection means, the control unit of the controller further outputs the stop signal on condition that the pressure detection means detects a pressure equal to or higher than a predetermined stop pressure. The compressed air supply system according to claim 4.

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