JP4483875B2 - Adsorption type oxygen concentrator - Google Patents

Description

  The present invention relates to an adsorption-type oxygen concentrator. More specifically, the present invention relates to an adsorptive oxygen concentrator capable of stopping operation when an abnormality that affects safety occurs and continuing operation as much as possible when other abnormality occurs.

  Adsorption type (PSA type) is mainly used as an oxygen concentrator used for home oxygen therapy in which patients with respiratory diseases inhale oxygen at home. This adsorption type (PSA type) oxygen concentrator supplies oxygen enriched air to the user in the following manner. First, the outside air is compressed by a compressor and sent to an adsorption cylinder filled with an adsorbent that adsorbs nitrogen. Nitrogen in the compressed air is adsorbed by the adsorbent in the adsorption cylinder, and oxygen-enriched air having a relatively increased oxygen concentration is supplied to the user. At this time, the oxygen concentration, supply amount, and pressure of the oxygen-enriched air are measured by a sensor, and the control means controls a motor that drives the compressor through a motor drive driver circuit (hereinafter simply referred to as a driver) according to the results.

  As a motor used for such an adsorption type oxygen concentrator, a DC brushless motor which is highly efficient and hardly generates noise is generally used. When driving this DC brushless motor, the driver needs to recognize the position of the rotating part (rotor) of the motor, but there are many sensorless type DC brushless motors that do not have a special sensor for detecting the rotor position. Used. In this sensorless type DC brushless motor, the driver measures the voltage supplied to the motor and detects the rotor position from the change. Accordingly, the sensor for detecting the rotor position becomes unnecessary, and as a result, there is no need to provide wiring from the sensor, which contributes to miniaturization and easy design. However, since the change in the supply voltage to be detected is minute, the detection accuracy of the rotor position is greatly affected by noise, and if the noise is too large, detection is impossible. That is, the sensorless type DC brushless motor is particularly vulnerable to noise, and abnormalities such as inability to detect the rotor position may occur accidentally due to the noise.

  Here, when the control means detects an abnormality of the motor or driver, the control means immediately stops the operation of the oxygen concentrator, notifies the user of the abnormality by a buzzer, LED, etc., and prompts the user to contact the manufacturer. . By performing such an abnormality process, even when a serious abnormality leading to a failure or failure of the motor or driver occurs, the abnormality or failure level can be minimized, and the abnormality or failure can be propagated to other locations. It can be avoided.

  However, when the abnormal processing as described above is performed, the operation of the oxygen concentrator is stopped until a response is made by the manufacturer who received the user's communication. It is a big problem for the user that the oxygen concentrator, which is a medical device, is stopped for a long time until the manufacturer supports it. On the other hand, if a complaint is frequently generated for a manufacturer, the cost of handling it becomes a heavy burden. In particular, in an oxygen concentrator using a sensorless type DC brushless motor, an abnormal stop due to noise can easily occur as described above, which is particularly problematic. In addition, the oxygen concentrator is portable, and there is a strong demand for downsizing. Therefore, the components of the oxygen concentrator are designed close to each other and easily affected by radiation noise. Therefore, there is a high probability that the operation will frequently stop.

Therefore, it is distinguished whether the abnormality of the motor or driver is due to a failure or a serious abnormality leading to the failure, or an accidental abnormality caused by noise or the like, for example, the above-described rotor position detection failure or the like. Then, it is desirable to restart automatically after a short stop. Therefore, for example, Patent Document 1 introduces a compressor control device that performs the following processing. That is, when an abnormality of the compressor is detected, the control means abnormally stops the compressor and automatically restarts after the abnormality is released. At this time, the control means counts the number of times of abnormality detection. When the number of times of abnormality detection reaches a predetermined number, the control means does not restart the compressor even after the abnormality is canceled after abnormally stopping the compressor. This is because there may be a failure or a serious abnormality leading to the failure. Further, there is also shown a method of measuring the time from the occurrence of a certain abnormality to the next occurrence of the abnormality and clearing the number of times of abnormality detection when the predetermined time has passed.
Japanese Patent Laid-Open No. 10-16969

  However, since the PSA oxygen concentrator generates compressed air by a compressor, an abnormally high pressure may occur in the equipment. Unconditionally restarting in the event of an abnormally high pressure is a problem, especially considering that the adsorptive oxygen concentrator is mainly used indoors.

  In addition, the oxygen concentrator is strongly required to be non-stop because of its properties as a medical device, and it becomes a problem that the oxygen concentrator cannot be restarted unconditionally when the number of abnormality detection reaches a predetermined value.

  An object of the present invention is to provide an oxygen concentrator that reliably stops operation when an abnormally high pressure occurs, and continues operation when an abnormality that does not impair safety occurs.

An adsorption-type oxygen concentrator according to the present invention includes a compressor driven by a DC brushless motor, a motor drive driver circuit that controls the operation of the DC brushless motor, and an adsorption filled with an adsorbent that selectively adsorbs nitrogen. An adsorption type that supplies oxygen-enriched air with a relatively high oxygen concentration by sucking and compressing outside air by the compressor and removing nitrogen in the outside with the adsorbent in the adsorption cylinder It is an oxygen concentrator. And an abnormality detecting means for detecting at least an abnormality in the driver circuit for driving the motor, an abnormality in the DC brushless motor, other abnormality in the compressor, and a pressure in the adsorption oxygen concentrator, and an abnormality occurs. An abnormality notification means for informing the user that the operation has been performed, and a control means for controlling the operation of the adsorption oxygen concentrator based on a determination based on the result detected by the abnormality detection means. Further, when the abnormality detecting means detects any abnormality of the driver circuit for driving the motor, abnormality of the DC brushless motor or other abnormality of the compressor, the control means stops the operation of the compressor, and the pressure There the case of more than the threshold value activates the abnormality notification means together for stopping the operation of the adsorber type oxygen concentrator, when the pressure is less than the threshold value, and characterized in that to restart the compressor To do.

Pressure exceeds the threshold value of the adsorption type in oxygen concentrator According to this configuration, abnormality is informed in case a failure spillover hazards and safety issues may have occurred, and the adsorption-type oxygen concentrator is stopped driving. Therefore, this adsorption type oxygen concentrator effectively suppresses the occurrence of serious failures and safety problems. Further, it is determined that the pressure does not cause problems on the failed spread hazards and safety in the case of not exceeding the threshold value, by restarting the compressor to continue the operation of the oxygen concentrator. This ensures that the oxygen concentrator is not shut down in the event of an accident or minor failure.

Here, the threshold value is determined expediently in a range that does not cause danger or safety problems of failure spread. Specifically, it is determined in consideration of a necessary safety factor within a range in which failure due to pressure, for example, disconnection or breakage of piping or tubes, breakage of various valves or the like does not occur. The abnormality of the peripheral device is also included in the abnormality of the driver circuit for driving the motor, the abnormality of the DC brushless motor, and other abnormality of the compressor. For example, abnormalities such as wiring and signal wiring from a power source connected to a DC brushless motor, a compressor, or a driver circuit for driving a motor are also included. Further, as a matter of course, the restart here refers to restart performed by the control means, and does not include manual restart after the oxygen concentrator is stopped.

  In the adsorption oxygen concentrator according to the present invention, the control means includes a restart number measuring device for measuring the number of times the compressor has been restarted from the start of operation, and the restart recorded in the restart number measuring device. Preferably, when the number of activations is equal to or greater than a predetermined number, the control unit operates the abnormality notification unit.

  According to this configuration, when the number of restarts reaches the predetermined value for the oxygen concentrator, the control means operates only the abnormality notification means while continuing the operation. This allows the user to know that something is wrong before the oxygen concentrator stops. Since the operation does not stop at this time, the user's disadvantage is kept to a minimum. The predetermined value is determined by calculating the number of consecutive occurrences of abnormalities due to accidental causes, arithmetically, experimentally or empirically, and taking into account the necessary safety factor.

  Further, the adsorption oxygen concentrator according to the present invention is configured such that when the number of restarts recorded in the restart number measuring device exceeds a second predetermined number that is greater than the predetermined number, the control means It is preferable that the operation of the oxygen concentrator is stopped and the abnormality notifying means is operated.

  As described above, when the restart occurs many times, that is, when the abnormality occurs many times, the abnormality is not accidental, and it is considered that there is a fundamental reason for the occurrence of the abnormality. If the situation continues even after the abnormality notification means is activated, there is a high possibility that the user cannot take action or the user has not recognized the abnormality notification. In such a case, if it is left unattended that abnormalities occur continuously, there is a possibility that a failure will spread, a serious failure will occur, and a safety problem will occur. According to the above configuration, even when the number of restarts exceeds a predetermined value, the operation of the adsorption oxygen concentrator is stopped and the abnormality notification unit is operated, so that the occurrence of abnormality continues even after the abnormality notification unit is activated. Can be prevented.

  Note that the second predetermined value is set for a proper purpose within a range in which there is no risk of failure and safety problems. Specifically, calculate the number of restarts that may cause problems such as the spread of failure when restarting with a minor failure and continuing the operation, and estimate the required safety factor. Determined.

In the adsorption-type oxygen concentrator according to the present invention, the abnormality detecting means further detects the oxygen concentration of the oxygen-enriched air and the flow rate of the oxygen-enriched air, and the oxygen concentration of the oxygen-enriched air immediately before the stop of the compressor or when the flow rate of the oxygen-enriched air is less than the threshold value also, the control means is preferably to operate the abnormality notification means together for stopping the operation of the adsorber type oxygen concentrator.

The minimum threshold value that serves as an oxygen concentrator, to exceed the oxygen concentration and the oxygen enriched air flow rate of the oxygen enriched air supplied, there is no practical benefit even continue operation. On the other hand, there is a possibility that a failure will spread, a serious failure will occur, a safety problem, etc. may occur. According to the above configuration, in such a case, since the operation of the adsorption oxygen concentrator is stopped and the abnormality notification means is operated, secondary failure due to continuing meaningless operation is prevented, and the user is abnormal. Can be informed.

Incidentally, substantially calculated from a medical point of view or empirical standpoint of oxygen concentration and the oxygen enriched air flow rate can be said that by supplying oxygen enriched air, can be determined the threshold value based on such values.

  In the adsorption oxygen concentrator according to the present invention, the control means further includes an abnormality occurrence interval measuring device for measuring an abnormality occurrence time interval, and the abnormality occurs when the time interval is equal to or less than a predetermined value. Even when an abnormality has occurred continuously for a predetermined number of times or more, it is preferable that the control means stops the operation of the adsorption oxygen concentrator and activates the abnormality notification means.

  If the abnormality continues to occur at short time intervals and is repeated, such an abnormality is not accidental and it is considered that there is a fundamental reason for the occurrence of the abnormality. According to the above configuration, even when an abnormality occurs when the time interval is equal to or less than the predetermined value and the abnormality occurs continuously more than a predetermined number of times, the operation of the adsorption oxygen concentrator is stopped and the abnormality notification unit is Since the operation is performed, it is possible to prevent the failure from spreading by continuing the operation when it is considered that there is a fundamental reason for the occurrence of the abnormality.

  Note that the predetermined value of the time interval and the predetermined number of occurrences of abnormality are determined as appropriate within a range that does not cause a risk of failure and a safety problem. Specifically, if the operation is continued by continuing the restart while a minor failure has occurred, the predetermined time interval and the predetermined number of times that the failure may spill over may be experimentally or empirically determined. Calculated and determined based on the necessary safety factor.

  The adsorption oxygen concentrator according to the present invention is configured such that if the oxygen concentration of the oxygen-enriched air is equal to or less than a predetermined value, it is determined that an oxygen concentration abnormality has occurred, and the control means stops the operation of the compressor. And, within a certain period after the restart, the control means can continue the operation of the compressor regardless of the oxygen concentration of the oxygen-enriched air.

  In the adsorption-type oxygen concentrator, once the compressor is stopped, the oxygen concentration of the oxygen-enriched air becomes lower than that during normal operation for a certain period after the restart. This is a phenomenon that naturally occurs due to the structure of the adsorption oxygen concentrator, and the oxygen concentration is recovered by continuing the operation. However, if the compressor is stopped due to an oxygen concentration abnormality before the oxygen concentration is recovered, the oxygen concentration is lowered again at the time of restarting. Therefore, restarting and stopping of the compressor are frequently repeated, and the oxygen concentration is not recovered. According to the above configuration, the control means continues the operation of the adsorption oxygen concentrator regardless of the oxygen concentration of the oxygen-enriched air in a certain period after the restart, so that the compressor is restarted and stopped. Never repeat.

Here, the predetermined value relating to the oxygen concentration of the oxygen-enriched air is a value determined as follows. Even when the oxygen concentrator is operated in a state where no trouble has occurred, the oxygen concentration of the generated oxygen-enriched air changes due to normal deterioration of the adsorbent and measurement errors. The lower limit value of the oxygen concentration caused by such a normal change is calculated experimentally or empirically, and the predetermined value is determined in consideration of a necessary safety factor. The same predetermined value may be the same as "minimum threshold value which serves as an oxygen concentrator" described above, but usually the predetermined value becomes a larger value. Also, for the above-mentioned fixed period, when the compressor operation is temporarily stopped and then restarted in the normal operation state, the time during which the oxygen concentration of the oxygen-enriched air is equal to or greater than the predetermined value is calculated experimentally or empirically. It is determined in anticipation of the necessary safety factor.

  The adsorption-type oxygen concentrator according to the present invention further includes a recording unit that records the type of abnormality when the abnormality occurs, and when the control unit determines that the oxygen concentration abnormality has occurred within the certain period of time, It can be configured to record in the recording means while distinguishing into different types from when it is determined that the oxygen concentration abnormality has occurred outside the predetermined period.

  According to this configuration, it is possible to record the oxygen concentration abnormality of the oxygen-enriched air that occurred within a certain period after restarting, distinguishing it from the oxygen concentration abnormality of the oxygen-enriched air during normal operation, so it is convenient for investigating abnormality history Will improve.

  According to the present invention, it is possible to provide an oxygen concentrator that reliably stops operation when a high pressure abnormality occurs and continues operation when an abnormality that does not impair safety occurs.

  (First embodiment)

  Hereinafter, an embodiment of an adsorption oxygen concentrator embodying the present invention will be described with reference to FIGS.

  FIG. 1 is a block diagram of an adsorptive oxygen concentrator according to the first embodiment. This oxygen concentrator basically operates as follows. First, the air taken in by the compressor 1 and pressurized to a certain pressure is sent to the first adsorption cylinder 3 and the second adsorption cylinder 4 via the intake valves 21 and 22, respectively. The first adsorption cylinder 3 and the second adsorption cylinder 4 are each filled with an adsorbent that adsorbs nitrogen in the air, such as zeolite. Oxygen-enriched air having a relatively increased oxygen concentration is stored in the accumulator tank 5 by adsorbing nitrogen in the first adsorption cylinder 3 and the second adsorption cylinder 4. The compressor 1 is driven by a DC brushless motor 2. The pressure sensor 10 is provided in the pipe from the adsorption cylinders 3 and 4 to the accumulator tank 5 and the outlet pressure of the adsorption cylinders 3 and 4 is measured. If there is an abnormality, the exhaust valves 23 and 24 are opened and compressed. Air is exhausted.

  The oxygen-enriched air stored in the accumulator tank 5 is adjusted to a predetermined pressure by the pressure reducing valve 6, adjusted to the flow rate set by the flow rate regulator 7, and then released to the supply destination (medical site). An oxygen concentration sensor 11 and an oxygen-enriched air flow sensor 12 are provided in the pipe between the pressure reducing valve 6 and the flow rate regulator 7 to monitor the oxygen concentration and flow rate of the supplied oxygen-enriched air.

  FIG. 2 is a block diagram for explaining the configuration of the control means of the adsorption oxygen concentrator and its peripheral devices. In addition, the same code | symbol was attached | subjected about the same part as FIG.

  The microcontroller 31 which is a control means incorporates a CPU 32, an operation RAM 33, a program storage ROM 34, an abnormality occurrence interval measurement counter 35, an after-restart operation time counter 36 and a restart number counter 37.

  The CPU 32 controls the adsorption oxygen concentrator using the arithmetic RAM 33 in accordance with the execution program stored in the program storage ROM 34. When an abnormality is detected by various sensors, which will be described later, the abnormality occurrence interval measurement counter 35 is actuated at the time of occurrence to measure the occurrence interval of the abnormality. When the compressor 1 is restarted, the restart count recorded in the restart count counter 37 is incremented by 1, and the operation time after restart of the post-restart operation time counter 36 is counted.

  Devices that transmit various signals including the occurrence of abnormality to the microcontroller 31 include a pressure sensor 10, an oxygen concentration sensor 11, an oxygen-enriched air flow sensor 12, a setting operation unit 39, and a motor driver circuit 41. The pressure sensor 10 measures the pressure in the pipe connecting the first and second adsorption cylinders 3, 4 and the accumulator tank 5 and transmits it to the microcontroller 31. The oxygen concentration sensor 11 and the oxygen-enriched air flow sensor 12 measure the oxygen concentration and the flow rate of the oxygen-enriched air supplied to the user, and transmit them to the microcontroller 31. The setting operation unit 39 includes a main power switch, a flow rate setting knob, and the like, and transmits a signal set by the user or manufacturer as necessary to the microcontroller 31. The motor driver circuit 41 transmits to the microcontroller 31 signals indicating the operation and stop status of the DC brushless motor 2 and the occurrence of an abnormality.

  In response to the transmission from the various devices, the microcontroller 31 controls the compressor 1, the abnormality notifying means 38, the various display units 40, and the electromagnetic valves 6, 21, 22, 23, 24 via the motor driver circuit 41. Note that a data storage memory (EEPROM; ROM capable of erasing and writing data) 42 stores a history of the type and number of abnormalities and subsequent processing methods.

  Examples of the abnormality notification means 38 that informs the user that an abnormality has occurred and prompts the manufacturer to contact the manufacturer include a buzzer and an LED (light emitting diode). Examples of the various display units 40 include various setting contents, a display indicating normality or abnormality, a panel displaying an air flow state, an LED, a display, and the like.

  The compressor 1 is driven by a DC brushless motor 2, and the DC brushless motor 2 is directly controlled by a motor driver circuit 41. As described above, in order to drive the DC brushless motor 2, it is necessary to detect the position of the rotor. However, the motor driver circuit 41 measures the supply voltage to the DC brushless motor 2 without installing a special sensor for that purpose. A sensorless system that detects the rotor position based on the change is employed. Therefore, if noise enters the supply voltage, the rotor position cannot be detected, and the DC brushless motor 2 cannot be driven, and an abnormality may occur.

  The noise generation source includes an external source and an internal source. As external noise, for example, radiation noise of a dryer, a television, a fluorescent lamp or the like can be raised. It is difficult to take individual measures for these. Examples of internal components include noise generated by the motor driver circuit 41 itself, a power supply circuit (not shown) for generating a DC voltage from a commercial power supply, and the DC brushless motor 2. As oxygen concentrators are becoming more compact due to the need for portability, the tendency of these components that are sources of noise to be placed close to each other is increasing. It has also become difficult.

  However, abnormalities due to the occurrence of noise are accidental, and do not cause failure or peripheral failures. On the other hand, oxygen enrichment is a medical device, and continuous operation is strongly desired. Therefore, if the operation of the oxygen concentrator is stopped due to such abnormality, the user is disadvantaged. In addition, for the manufacturer, handling of complaints from the user that occurs each time the operation is stopped becomes excessive. Therefore, the adsorption oxygen concentrator according to the first embodiment performs the following control when an abnormality occurs.

  FIG. 3 is a flowchart showing the control performed by the microcontroller 31 when an abnormality (hereinafter simply referred to as a motor system abnormality) relating to the motor 2, the compressor 1, and the motor driver circuit 41 occurs. Hereinafter, the operation before and after an abnormality will be described with reference to FIG.

  When the normal operation time of the oxygen concentrator continues for a predetermined time or longer (step S1), the microcontroller 31 deletes the history related to the occurrence of the restart so far. Specifically, the restart number counter 37 and the post-restart operation time counter 36 are reset (steps S2 and S3). This is because if the restart due to the occurrence of an abnormality is not performed for a long time, the abnormality that has occurred so far cannot be considered to have a fundamental reason, and the probability of determining that a failure has occurred is low.

When a motor system abnormality occurs (step S4), first, the operation of the compressor 1 is stopped by stopping the operation of the motor 2 (step S5). Then check the pressure in the pipe is not an upper limit value (threshold value) or more by the pressure sensor 10 (step S6), and the oxygen concentration because the safety problem may have occurred if the high voltage of the upper limit value it takes The apparatus is stopped (step S15), an abnormality is notified (step S16), and an abnormality history is recorded in the data storage memory 42 (step S17).

  On the other hand, even if the pressure in the pipe is less than the upper limit value (step S6), if the number of restarts up to the previous time is equal to or greater than the predetermined value (A) (step S7), the abnormality notifying means 38 is operated to indicate an abnormality. The user is informed that the restart is continuing (step S8). This is because there seems to be a fundamental cause of abnormality. Further, if the number of restarts is equal to or greater than the predetermined value (B) (step S9), the oxygen concentrator is stopped (step S15), an abnormality is notified (step S16), and the abnormality history is recorded in the data storage memory 42. (Step S17). This is because it is considered that the fundamental cause of the abnormality has not been solved, and it is considered that there is a risk of a spillover of failure if the operation is continued. Here, the predetermined value (A) is calculated arithmetically, experimentally, or empirically as the number of times that it can be determined that the occurrence of abnormality is not due to an accidental cause but has a root cause and is continuously occurring. Determine the necessary safety factor. The predetermined value (B) is a value larger than the predetermined value (A), and the number of restarts that may cause a problem such as a spillover of the failure when the operation is continued while a slight failure has occurred is experimentally or Calculated empirically and determined based on the required safety factor.

  When the number of restarts is less than the predetermined value (A) (step S7) and when the number of restarts is less than the predetermined value (B) (step S9), the time interval from the previous abnormality occurrence to the current abnormality occurrence is abnormally generated. It confirms with the space | interval measurement counter 35 (step S10). If the time interval is equal to or less than the predetermined value, it is further confirmed whether or not the occurrence of an abnormality with the time interval equal to or less than the predetermined value continues for a predetermined number of times (step S11). If an abnormality that has occurred at a time interval of a predetermined value or less has occurred continuously for a predetermined number of times or more, the oxygen concentrator is stopped (step S15) and the abnormality is notified (step S16), and the abnormality history is stored in the data storage memory. 42 (step S17).

  When the time interval from the previous occurrence of the abnormality to the occurrence of the current abnormality exceeds a predetermined value, or when the number of consecutive occurrences of the abnormality is less than the predetermined number, the compressor 1 is restarted by restarting the operation of the motor 2. Start (step S12). This is because in such a case, there is a high possibility of an accidental abnormality due to noise or the like. Thereafter, the number of restarts stored in the restart counter 37 is incremented by 1 (step S13), the post-restart operation time counter 36 is operated (step S14), and the normal operation is resumed.

  According to the adsorption oxygen concentrator of the above embodiment, the following effects can be obtained.

(1) In the above embodiment, after the microcontroller 31 stops the compressor 1 when an abnormality occurs, since when the pipe pressure is equal to or greater than the threshold value stop the operation of the oxygen concentrator, to notify an abnormality, When a failure with a safety problem occurs, the operation can be stopped reliably and an abnormality can be notified.

(2) In addition, be less than the pipe pressure threshold value, number of restarts microcontroller 31 if the predetermined value (A) or to operate the abnormality notification unit. Therefore, the user can recognize the possibility that some unintentional abnormality has occurred, and can take countermeasures. In addition, since the operation of the oxygen concentrator continues, the user is not immediately disadvantaged.

  (3) Furthermore, if the number of restarts is equal to or greater than the predetermined value (B), the microcontroller 31 stops the operation of the oxygen concentrator and notifies the abnormality. Therefore, it is possible to effectively prevent the occurrence of a failure or a safety problem by leaving a non-accidental abnormality.

  (4) Furthermore, even when an abnormality occurs when the time interval is equal to or less than a predetermined value and the abnormality occurs continuously more than a predetermined number of times, the microcontroller 31 stops the operation of the adsorption oxygen concentrator. The abnormality notification means is activated. Therefore, it is possible to effectively prevent the occurrence of a failure or a safety problem by leaving a non-accidental abnormality.

  (5) In the above embodiment, when none of the above (1), (3), and (4) is satisfied, the microcontroller 31 restarts the motor 2 to restart the compressor 1, so that the operation of the oxygen concentrator is performed. Can continue. Therefore, the operation of the oxygen concentrator is not stopped in the event of accidental or minor failure that does not affect the spread of safety or safety. Therefore, it is possible to reduce the burden of manufacturers' complaints by suppressing the disadvantages of users who cannot use oxygen concentrators as medical instruments for a long time and by reducing complaints due to accidental abnormalities that do not cause failure and safety problems. it can.

  In addition, you may change the said embodiment as follows.

  (Modification 1) It is not indispensable to measure the number of restarts by the restart number counter 37 and to measure the time interval of occurrence of the abnormality by the abnormality occurrence interval measurement counter 35, either or both are omitted. May be. In short, it is only necessary to stop the operation of the oxygen concentrator when an abnormal high pressure occurs, and to continue the operation of the oxygen concentrator when an abnormal condition that does not impair safety occurs. 1 may be restarted, and the operation of the oxygen concentrator may be stopped if the upper limit is exceeded. Such a configuration simplifies the structure and contributes to the development period and production cost reduction in the oxygen enrichment period.

  (Modification 2) In the first embodiment, the buzzer and the LED are adopted as the abnormality notification means, but other notification means may be used. For example, the occurrence of an abnormality may be displayed on a display, or a configuration for notifying the occurrence of an abnormality at another place (manufacturer or the like) through a communication line may be employed.

  (Modification 3) In the first embodiment, an EEPROM (ROM capable of erasing and writing data) is used as the data storage memory 42. However, other nonvolatile memories such as a flash memory may be used. A media medium such as a hard disk or an IC card may be used. In particular, when an IC card or the like is used, it is easy to remove, so that an abnormality history can be analyzed with an external computer or the like, which is preferable.

  (Modification 4) Further, in the first embodiment, if the oxygen concentration of the oxygen-enriched air is equal to or lower than a predetermined value, it is determined that an oxygen concentration abnormality has occurred, and the microcontroller 31 stops the operation of the compressor 1. In addition, the microcontroller 31 can continue the operation of the compressor 1 regardless of the oxygen concentration of the oxygen-enriched air within a certain period after the restart of the compressor 1.

  According to the above modification, even if the oxygen concentrator is configured to stop the compressor when an oxygen concentration abnormality occurs, the compressor is restarted and stopped due to an oxygen concentration abnormality that naturally occurs in a certain period after the restart. Never repeat.

  (Modification 5) In addition to the above modification, when it is determined that an oxygen concentration abnormality has occurred within a certain period after the compressor 1 is restarted, the oxygen concentration abnormality is outside the certain period after the compressor 1 is restarted. It is possible to adopt a configuration in which data is recorded in the data storage memory 42 while being distinguished by a different type from when it is determined that the occurrence has occurred. According to this configuration, it is possible to record the oxygen concentration abnormality of the oxygen-enriched air that occurred within a certain period after restarting, distinguishing it from the oxygen concentration abnormality of the oxygen-enriched air during normal operation, which is convenient for investigating abnormal history Will improve.

  (Second Embodiment)

  Next, a second embodiment of the adsorption oxygen concentrator embodying the present invention will be described with reference to FIG. Note that the second embodiment has a configuration in which the processing method at the time of occurrence of abnormality in the first embodiment is changed, and the device configuration is the same as that in FIGS. 4 will not be described in detail for the same parts as in FIG.

  FIG. 4 is a flowchart showing the control performed by the microcontroller 31 when a motor system abnormality occurs. Hereinafter, the operation before and after an abnormality will be described with reference to FIG.

  When the normal operation time of the oxygen concentrator continues for a predetermined time or more (step S21), the microcontroller 31 resets the restart count counter 37 and the restart operation time counter 36 (step S22, step S23). . This is because if the restart due to the occurrence of an abnormality is not performed for a long time, the abnormality that has occurred so far cannot be considered to have a fundamental reason, and the probability of determining that a failure has occurred is low.

When a motor system abnormality occurs (step S24), the operation of the compressor 1 is first stopped by stopping the operation of the motor 2 (step S25). Then check the pressure in the pipe is not an upper limit value (threshold value) or more by the pressure sensor 10 (step S26), the oxygen concentration because the safety problem may have occurred if the high voltage of the upper limit value it takes The apparatus is stopped (step S35), an abnormality is notified (step S36), and an abnormality history is recorded in the data storage memory 42 (step S37).

On the other hand, be less than the upper limit value of the pressure in the pipe (step S26), if the operation of the compressor 1 is less than the oxygen concentration and flow rate threshold value of the oxygen enriched air immediately before stopping, it stops the oxygen concentrator (step S35), the abnormality is notified (step S36), and the abnormality history is recorded in the data storage memory 42 (step S37). This is because even if the operation is continued while the oxygen concentration and the flow rate of the oxygen-enriched air to be supplied are extremely low, the function of the oxygen concentrator is not exhibited and there is no actual benefit of continuing the operation. On the other hand, there is a probability that a failure will spread, a serious failure will occur, or a safety problem may occur.

In the case of oxygen concentration and flow rate of the oxygen enriched air is the threshold value anomaly, if the reboot count up to the previous predetermined value (A) above (step S27), the abnormality and re actuates the abnormality notification means 38 The user is informed that the activation is continuing (step S29). This is because there seems to be a fundamental cause of abnormality. Unlike the first embodiment, the predetermined value (B) is not set, and only when the number of restarts is large, the oxygen concentrator is stopped (step S35) and an abnormality is notified (step S36). There is no. Even fundamental cause of the abnormality is not resolved, if the oxygen concentration and flow rate of the oxygen-enriched air or more threshold values, because large benefits of possible to continue the operation. Here, the predetermined value (A) is calculated arithmetically, experimentally, or empirically as the number of times that the occurrence of abnormality is not due to an accidental cause but has a root cause and can be determined to occur continuously. Determine the necessary safety factor.

  Furthermore, the time interval from the occurrence of the previous abnormality to the occurrence of the current abnormality is confirmed by the abnormality occurrence interval measurement counter 35 (step S30). If the time interval is equal to or less than the predetermined value, it is further confirmed whether or not the occurrence of an abnormality with the time interval equal to or less than the predetermined value continues for a predetermined number of times (step S31). If an abnormality that has occurred at a time interval of a predetermined value or less has occurred continuously for a predetermined number of times or more, the oxygen concentrator is stopped (step S35), and the abnormality is notified (step S36), and the abnormality history is stored in the data storage memory. It is recorded in (EEPROM) 42 (step S37).

  When the time interval from the previous occurrence of the abnormality to the occurrence of the current abnormality exceeds a predetermined value, or when the number of consecutive occurrences of the abnormality is less than the predetermined number, the compressor 1 is restarted by restarting the operation of the motor 2. Start (step S32). This is because in such a case, there is a high possibility of an accidental abnormality due to noise or the like. Thereafter, the number of restarts stored in the restart counter 37 is incremented by 1, and the operation time counter 36 after restart is operated to return to normal operation.

  According to the adsorption oxygen concentrator of the second embodiment, the following effects can be obtained.

(1) In the above embodiment, after the microcontroller 31 stops the compressor 1 when an abnormality occurs, since when the pipe pressure is equal to or greater than the threshold value stop the operation of the oxygen concentrator, to notify an abnormality, When a failure with a safety problem occurs, the operation can be stopped reliably and an abnormality can be notified.

(2) If the operation of the compressor 1 is less than the oxygen concentration and flow rate threshold value of the oxygen enriched air immediately before stop, notifies the abnormality to stop the oxygen concentrator. For this reason, the oxygen concentrator continues to operate substantially without any profit, and on the contrary, it is possible to prevent the occurrence of failure, occurrence of serious failure, safety problems, and the like.

  (3) Furthermore, if the number of restarts is equal to or greater than the predetermined value (A), the microcontroller 31 activates the abnormality notifying means. Therefore, the user can recognize the possibility that an abnormality having some fundamental reason has occurred, and can take countermeasures. In addition, since the operation of the oxygen concentrator continues, the user is not immediately disadvantaged.

  (4) Furthermore, even when an abnormality occurs when the time interval is equal to or less than a predetermined value and the abnormality occurs continuously more than a predetermined number of times, the microcontroller 31 stops the operation of the adsorption oxygen concentrator. The abnormality notification means is activated. Therefore, it is possible to effectively prevent the occurrence of a failure or a safety problem by leaving a non-accidental abnormality.

  (5) In the above embodiment, if none of the above (1), (2), and (4) is satisfied, the microcontroller 31 restarts the motor 2 to restart the compressor 1, so that the operation of the oxygen concentrator is performed. Can continue. Therefore, the operation of the oxygen concentrator is not stopped in the event of accidental or minor failure that does not affect the spread of safety or safety. Therefore, by suppressing the disadvantages of users who cannot use the oxygen concentrator as a medical device for a long time, and reducing the complaints due to accidental abnormalities that do not cause failure and safety problems, the load of the manufacturer's complaints can be reduced. The reliability of the oxygen concentrator can be increased.

  Also in the above-described embodiment, the same changes as (Modification 1) to (Modification 5) shown in the first embodiment are possible. Furthermore, the changes shown in the following (Modification 6) are also possible.

(Modification 6) In the second embodiment, the predetermined value (B) of the number of restarts is not set, but the number of restarts exceeds the predetermined value (B) as in the first embodiment. In this case, the oxygen concentrator may be stopped and an abnormality may be notified. In such a case, there is the oxygen concentration and flow rate of the oxygen enriched air is the oxygen concentrator even thresholds abnormality is stopped, but the convenience of the user decreases, and the effect of suppressing the spread of failure, improved safety Useful.

The block diagram which shows the whole structure of the 1st Embodiment about the adsorption type oxygen concentrator which concerns on this invention. The block diagram explaining the structure of the microcontroller employ | adopted as the motor control circuit of the embodiment. The flowchart which shows the example of a process sequence at the time of motor system abnormality generation | occurrence | production of the microcontroller employ | adopted for the adsorption type oxygen concentrator of the embodiment. The flowchart which shows the process sequence example at the time of motor system abnormality generation | occurrence | production of the microcontroller employ | adopted as the adsorption type oxygen concentrator of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Compressor 2 Motor 3 1st adsorption cylinder 4 2nd adsorption cylinder 5 Accumulator tank 6 Pressure-reducing valve 7 Flow regulator 10 Pressure sensor 11 Oxygen concentration sensor 12 Oxygen-concentrated air flow sensor 21, 22 Intake valve 23, 24 Exhaust valve 31 Microcontroller 32 CPU
33 RAM for calculation
34 Program storage ROM
35 Anomaly occurrence interval measurement counter 36 Operation time counter after restart 37 Number of restart counters 38 Abnormality notification means 39 Setting operation section 40 Various display sections 41 Motor driver circuit 42 Memory for data storage

Claims (7)

A compressor driven by a DC brushless motor;
A motor driving driver circuit for controlling the operation of the DC brushless motor;
An adsorption cylinder filled with an adsorbent that selectively adsorbs nitrogen,
In the adsorption-type oxygen concentrator for supplying oxygen-enriched air having a relatively high oxygen concentration by sucking and compressing outside air by the compressor and removing nitrogen in the outside air with the adsorbent in the adsorption cylinder,
An abnormality detection means for detecting at least an abnormality of the driver circuit for driving the motor, an abnormality of the DC brushless motor, other abnormality of the compressor, and a pressure in the adsorption oxygen concentrator;
An abnormality notification means for informing that an abnormality has occurred;
Control means for controlling the operation of the adsorption oxygen concentrator based on the determination based on the result detected by the abnormality detection means,
When the abnormality detecting means detects any of the abnormality of the driver circuit for driving the motor or the abnormality of the DC brushless motor or other abnormality of the compressor, the control means stops the operation of the compressor,
If the pressure is not less than the threshold value activates the abnormality notification means together for stopping the operation of the adsorber type oxygen concentrator,
If the pressure is less than the threshold value, the adsorption type oxygen concentrator, characterized in that to restart the compressor. The adsorption oxygen concentrator according to claim 1,
The control means comprises a restart number measuring device for measuring the number of times the compressor has been restarted from the start of operation,
When the number of restarts recorded in the restart number measuring device is a predetermined number or more,
The adsorption oxygen concentrator, wherein the control means operates the abnormality notifying means. The adsorption oxygen concentrator according to claim 2,
When the restart count recorded in the restart count measuring device exceeds a second predetermined count greater than the predetermined count,
The adsorption oxygen concentrator, wherein the control means stops the operation of the adsorption oxygen concentrator and activates the abnormality notification means. In the adsorption type oxygen concentrator described in any one of claims 1 to 3,
The abnormality detecting means further detects the oxygen concentration of the oxygen-enriched air and the flow rate of the oxygen-enriched air;
Even when the oxygen concentration or flow rate of said oxygen enriched air of the oxygen-enriched air in the stop just before the compressor is less than the threshold value,
The adsorption oxygen concentrator characterized in that the control means stops the operation of the adsorption oxygen concentrator and activates the abnormality notification means. In suction Chakushiki oxygen concentrator described in any one of claims 1 to 4,
The control means further comprises an abnormality occurrence interval measuring device that measures an abnormality occurrence time interval,
Even when the time interval is not more than a predetermined value and an abnormality has occurred, and the abnormality has occurred continuously for a predetermined number of times,
The adsorption oxygen concentrator, wherein the control means stops the operation of the adsorption oxygen concentrator and activates the abnormality notification means. The adsorption-type oxygen concentrator according to claim 4 or 5, wherein if the oxygen concentration of the oxygen-enriched air is equal to or less than a predetermined value, it is determined that an oxygen concentration abnormality has occurred, and the control means stops the operation of the compressor. In
Within a certain period after restart, regardless of the oxygen concentration of the oxygen enriched air,
The adsorption oxygen concentrator, wherein the control means continues the operation of the compressor. The adsorption oxygen concentrator according to claim 6,
It further comprises recording means for recording the type of abnormality when an abnormality occurs,
When the control means determines that the oxygen concentration abnormality has occurred within the predetermined period, it is recorded in the recording means by distinguishing it from a different type from when it is determined that the oxygen concentration abnormality has occurred outside the predetermined period. An adsorptive oxygen concentrator.

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