Automatic control device

Abstract

To provide an automatic controller that enables a state quantity to be adjusted to a user's desired level, thereby enhancing a user comfort and also attaining an energy-saving effect.SOLUTION: An automatic controller includes a mixed gas sensor 1, and a controller 2 that performs strong notch operation to feedback control a blower 5 so that output from the mixed gas sensor 1 becomes smaller than a target value. If output from the mixed gas sensor 1 is greater than the target value when a first time period has elapsed after starting the strong notch operation, the controller 2 determines whether the output from the mixed gas sensor 1 is in a saturated state, remaining within a first range for a second time period or longer. If the output from the mixed gas sensor 1 is determined to be in the saturated state, a difference between the output from the mixed gas sensor 1 and a first reference value is determined. If the difference is greater than a first threshold, the strong notch operation is continued, but if the difference is smaller than the first threshold, the strong notch operation is stopped.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an automatic control device that controls a ventilation machine that ventilates a room. [Background technology]

[0002] In an automatic control device for a ventilation device having a function of adjusting indoor air quality, a state quantity such as indoor miscellaneous gas concentration or humidity is detected by a state quantity detection means, and the ventilation device is controlled so that the state quantity becomes a target value. For example, when the indoor air becomes polluted below the target value due to cigarette smoke or the like, the device starts operation, exhausts the polluted indoor air to the outside, and introduces fresh outside air, and ventilates until the indoor air reaches a preset cleanliness level. However, the detection output of the state quantity by the state quantity detection means varies depending on the detection capability of the state quantity detection means, the adjustment capability of the state quantity of the controlled object, the installation environment, etc., and therefore tends to be difficult to converge to the target value, and there are cases where the controlled object continues to be controlled in a manner that deviates from the actual state.

[0003] For example, a miscellaneous gas sensor that detects the degree of air pollution reacts to a wide variety of gas components contained in the air, and if the detection target is, for example, an odor component associated with smoking, the sensor may actually reduce the level of the detection target to a target value, but may continue to output an output value that has not been reduced to the target value due to reaction to other components as detection information for a long time. In other words, the sensor falls into a saturated state in which the output of the miscellaneous gas sensor hardly changes and does not converge to the target value for a long time. When the sensor falls into a saturated state, the controlled object continues to be controlled, and the control does not stop for a long time, unlike the operation expected by the user.

[0004] To solve such problems, Patent Document 1 performs a saturation determination process in which it is determined whether the indoor air is polluted when a set time has elapsed since the start of strong notch operation of the ventilation device, and if it is determined that the indoor air is polluted, it is determined that the output of the state quantity detection means is in a saturated state. If the saturation determination is established, the strong notch operation is stopped and the operation is switched to weak notch operation, and if the saturation determination is not established, the strong notch operation is continued. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-310480 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in Patent Document 1, even if the output of the state quantity detection means remains higher than the target value, if the saturation determination is established, the strong notch operation is stopped, and thereafter, the state quantity cannot be adjusted, which is an issue. In other words, if the detection target is, for example, an odor component associated with smoking, even if the atmosphere has a strong odor, if there is no change in the odor, the function to reduce the odor is stopped, and the strong odor atmosphere is maintained.

[0007] The present disclosure has been made in consideration of the above, and aims to obtain an automatic control device that can adjust state quantities to amounts expected by a user, thereby improving user comfort and achieving energy saving effects. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the object, an automatic control device of the present disclosure controls a ventilation machine that ventilates a first space that is an indoor space. The automatic control device includes a first detection unit that detects and outputs a state quantity of an airborne substance in the first space, and a control unit that performs a first operation that feedback controls the ventilation machine so that the output of the first detection unit is smaller than a target value. When a first time has elapsed after the start of the first operation, the control unit performs a first process to determine whether or not the output of the first detection unit is in a saturated state that is within a first range for a second time or more if the output of the first detection unit is greater than the target value, and performs a second process to calculate the difference between the output of the first detection unit and a first reference value if the difference is greater than a first threshold value, and to continue the first operation if the difference is smaller than the first threshold value. Effect of the Invention

[0009] According to the automatic control device of the present disclosure, it is possible to adjust the state quantity to a quantity expected by the user, thereby improving the comfort of the user and achieving an energy saving effect. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram showing a configuration of an automatic control device according to a first embodiment. [Diagram 2] A flowchart showing the operation procedure of the control unit of the automatic control device according to the first embodiment. [Diagram 3] A time chart for explaining the control operation of the automatic control device according to the first embodiment. [Figure 4] FIG. 11 is a block diagram showing a configuration of an automatic control device according to a second embodiment. [Diagram 5] A flowchart showing the operation procedure of a control unit of an automatic control device according to a second embodiment. [Figure 6] FIG. 11 is a block diagram showing a configuration of an automatic control device according to a third embodiment. [Figure 7] A flowchart showing the operation procedure of a control unit of an automatic control device according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an automatic control device according to an embodiment will be described in detail with reference to the drawings.

[0012] Embodiment 1 FIG. 1 is a block diagram showing the configuration of an automatic control device according to a first embodiment. The controlled object of the automatic control device according to the first embodiment is a ventilation device having a ventilation function capable of adjusting state quantities including gas concentration and humidity in a certain room, which is a first space. The ventilation device is provided with a blower 5, which is a ventilation machine. The automatic control device is incorporated in the ventilation device and includes a miscellaneous gas sensor 1 as a first detection unit that detects state quantities, a control unit 2 including a microcomputer, and a drive circuit including a strong notch operation drive circuit 3 and a weak notch operation drive circuit 4. The miscellaneous gas sensor 1 detects and outputs state quantities including the gas concentration in the room. The weak notch operation drive circuit 4 drives and controls the blower 5 so as to perform weak notch operation. The strong notch operation drive circuit 3 drives and controls the blower 5 so as to perform strong notch operation, which is an operation with a stronger air volume than weak operation. The strong notch operation by the strong notch operation drive circuit 3 corresponds to the first operation. The control unit 2 feedback controls the blower 5 by the drive circuit so that the output of the miscellaneous gas sensor 1 is smaller than a preset target value.

[0013] Fig. 2 is a flowchart showing the operation procedure of the control unit 2 of the automatic control device according to the first embodiment. Fig. 3 is a time chart for explaining the control operation of the automatic control device according to the first embodiment. The vertical axis of the upper diagram of Fig. 3 is the output of the miscellaneous gas sensor 1, and the horizontal axis is time. The vertical axis of the lower diagram of Fig. 3 is the fan speed of the blower 5, and the horizontal axis is time. In Fig. 3, strong notch operation is abbreviated as strong operation, and weak notch operation is abbreviated as weak operation.

[0014] The control operation of the automatic control device in the first embodiment will be described with reference to Figs. 2 and 3. The automatic control device starts automatic operation (step S100). For example, when smoke is generated indoors due to smoking, the miscellaneous gas sensor 1 reacts to the smoke and shows a steep rise in output (voltage) as shown in Fig. 3. The control unit 2 takes in the output of the miscellaneous gas sensor 1. When the output of the miscellaneous gas sensor 1 becomes larger than a preset target value C1 (time t0, step S110: Yes), the control unit 2 operates the blower 5 in strong notch mode via the strong notch operation drive circuit 3 (step S120). When the output of the miscellaneous gas sensor 1 is equal to or smaller than the target value C1 (step S110: No), the control unit 2 stops the blower 5 (step S115).

[0015] By operating the blower 5 at the strong notch, the air in the room is gradually purified, and the output of the miscellaneous gas sensor 1 also decreases accordingly (time t0 to t1). The control unit 2 counts the elapsed time from when the blower 5 started to operate at the strong notch. When the elapsed time has passed a preset first time T0 (step S130: Yes), the control unit 2 judges whether the output of the miscellaneous gas sensor 1 is greater than the target value C1 (step S140). When the output of the miscellaneous gas sensor 1 is smaller than the target value C1 (step S140: No), the control unit 2 operates the blower 5 at the weak notch via the weak notch operation drive circuit 4, and then stops the blower 5 after the set time has elapsed (step S150). After this, the procedure proceeds to step S110.

[0016] When the output of the miscellaneous gas sensor 1 is greater than the target value C1 (step S140: Yes), the control unit 2 performs a saturation determination to determine whether or not the output of the miscellaneous gas sensor 1 is saturated (steps S160, S170). In the saturation determination, it is determined whether or not the output of the miscellaneous gas sensor 1 has been within a first range between an upper limit value and a lower limit value for a period of a preset second time T2 or more.

[0017] For example, if the output of the miscellaneous gas sensor 1 at time t1 when the first time T0 has elapsed since the output of the miscellaneous gas sensor 1 exceeded the preset target value C1 is set as a value A, A+α(V) is set as the upper limit value Amax of the saturation judgment region, and A-α(V) is set as the lower limit value Amin of the saturation judgment region. V is in volts. α is a preset value, for example, 0.1. Then, the control unit 2 stores the output of the miscellaneous gas sensor 1 at times t2, t3, and t4, which are times for each fixed time T1 (for example, 10 minutes) obtained by dividing the second time T2 (for example, 30 minutes) into a plurality of periods, in a memory (not shown) in the control unit 2. If the output of the miscellaneous gas sensor 1 at all times including times t1, t2, t3, and t4 is within the range between the upper limit value Amax and the lower limit value Amin, the control unit 2 determines that the miscellaneous gas sensor 1 is saturated (step S170: Yes).

[0018] If it is determined that the miscellaneous gas sensor 1 is not saturated (step S170: No), the control unit 2 shifts the procedure to step S110. Note that in the second and subsequent saturation determinations, the upper limit value Amax and the lower limit value Amin for the saturation determination are reset and the saturation determination is executed. The processes from step S100 to step S170 correspond to the first process.

[0019] When the control unit 2 determines that the miscellaneous gas sensor 1 is saturated (step S170: Yes), it compares the output of the miscellaneous gas sensor 1 with a judgment reference value K (step S180). The judgment reference value K corresponds to a first reference value. The judgment reference value K is a value for determining whether or not there is still room for the indoor air to be purified. The control unit 2 stores in memory, as the judgment reference value K, the minimum output of the miscellaneous gas sensor 1 in the past (for example, within 24 hours). The judgment reference value K may be determined by selecting the minimum output of the past and multiple outputs close to the minimum output, and using the average value of the selected multiple outputs.

[0020] When the saturation determination is established, the control unit 2 compares the output of the miscellaneous gas sensor 1 at time t4, which is the last time in the saturation determination period, with the determination reference value K, and determines whether the difference between the output of the miscellaneous gas sensor 1 at time t4 and the determination reference value K is equal to or greater than the threshold value C2, which is the first threshold value (step S190). If the difference is equal to or greater than the threshold value C2 (step S190: Yes), the control unit 2 determines that there is still room for the indoor air to be purified, and operates the blower 5 at the strong notch via the strong notch operation drive circuit 3 to continue the strong notch operation (step S200). On the other hand, if the difference is less than the threshold value C2 (step S190: No), the control unit 2 determines that there is no room for the indoor air to be purified any more, and switches the blower 5 to the weak notch operation via the weak notch operation drive circuit 4 (step S210). After the process of step S200 or the process of step S210 is executed, the procedure proceeds to step S140. In this way, when the output of the miscellaneous gas sensor 1 at time t4 is greater than the judgment reference value K by the threshold value C2 or more, the control unit 2 determines that there is still room for purification of the indoor air, and continues the strong notch operation. The processing from step S170 to step S210 corresponds to the second processing.

[0021] 3, the difference between the output of the miscellaneous gas sensor 1 and the judgment reference value K is equal to or larger than the threshold value C2, so the strong notch operation continues. Also, at time t5, the difference between the output of the miscellaneous gas sensor 1 and the judgment reference value K is smaller than the threshold value C2, so the strong notch operation is switched to the weak notch operation.

[0022] In Patent Document 1, when the saturation determination is made, the blower 5 is always switched to weak notch operation, so the miscellaneous gas sensor output and fan speed during the period from time t4 to time t5 in Fig. 3 are shown by the dashed line. In contrast, in the first embodiment, when the saturation determination is made, if there is still room for the indoor air to be purified, strong notch operation is continued, and if there is no room for purification, the notch operation is switched to weak notch operation.

[0023] In this way, in the first embodiment, the state quantity of the gas concentration can be adjusted to the amount expected by the user, improving comfort. Also, when there is no room to adjust the state quantity of the gas concentration to the amount expected by the user, the operation level is lowered to achieve an energy saving effect.

[0024] The output of the miscellaneous gas sensor 1 may fluctuate or become difficult to converge due to the influence of the installation environment of the automatic control device, the conditions of use, the season, the characteristics of the miscellaneous gas sensor 1, etc. As a result, the blower 5 of the ventilation system may not switch to weak notch operation for a long time, which is different from the operation expected by the user. However, in the first embodiment, even if the air is saturated, if there is no room for purification, the operation is quickly switched to weak notch operation.

[0025] Also, if the detection target is, for example, odor components associated with smoking, a person who has been in the room for a long time may become accustomed to the strong odor and not feel uncomfortable, but a person who comes from a weak odor atmosphere into a strong odor atmosphere will often feel uncomfortable because they have not acclimatized to the odor. In the first embodiment, even if the saturation state is reached, the purification operation will continue if there is room for purification, so it is also effective in such cases.

[0026] In the above description, the minimum past output of the miscellaneous gas sensor 1 stored in memory is within 24 hours. This makes it possible to eliminate the influence of the installation environment, operating conditions, seasons, etc. of the automatic control device on the output of the miscellaneous gas sensor 1, but if it is desired to eliminate the influence of factors that cause the output of the miscellaneous gas sensor 1 to fluctuate in units of hours, for example, this can be achieved by changing the minimum past output of the miscellaneous gas sensor 1 stored in memory to, for example, within one hour.

[0027] A method for changing how many hours back in the past the output of the miscellaneous gas sensor 1 to be stored in the memory can be realized, for example, by installing a volume resistor or the like in the control unit 2 and having the user operate the volume resistor. In this way, by allowing the user to change how many hours back in the past the output of the miscellaneous gas sensor 1 to be stored in the memory, it is possible to realize operation according to the user's preference.

[0028] As described above, when the control unit 2 determines that there is no room to purify the air in the room when the saturation judgment is made, it switches the operation of the ventilation device's blower 5 from a strong notch to a weak notch, but it may also switch the blower 5 from operating to stopped.

[0029] Furthermore, the first time T0, the second time T2, the third time T3, the target value C1, and the threshold value C2 may be set to appropriate values ​​taking into consideration the ventilation capacity of the ventilation device and the conditions in the room in which the ventilation device is installed.

[0030] Furthermore, in the above description, a ventilation device has been taken as an example, but similar effects can be obtained by controlling an air purifier that circulates and purifies indoor air in the same way.

[0031] The automatic control device of the first embodiment can also be adapted to control objects having a function of adjusting state quantities such as humidity, temperature, dust, and carbon dioxide by changing the state quantity detection means to a humidity sensor, a temperature sensor, a dust sensor, or a CO2 sensor. It is also possible to provide several types of state quantity detection means in parallel and switch the state quantity detection by the switching means, allowing the combination to be selected. By adopting such a configuration, it is possible to control operations according to the user's preferences.

[0032] Embodiment 2 Fig. 4 is a block diagram showing the configuration of an automatic control device according to embodiment 2. In embodiment 2, in addition to miscellaneous gas sensor 1 that detects and outputs the state quantity of gas concentration in a room, which is a first space, there is a miscellaneous gas sensor 6 that is provided in a second space different from the first space and detects and outputs the state quantity of airborne substances in the second space. Miscellaneous gas sensor 6 detects gas concentration in a corridor or outdoors, for example. Other configurations are the same as those in embodiment 1, and overlapping explanations will be omitted.

[0033] Fig. 5 is a flowchart showing the operation procedure of the control unit 2 of the automatic control device according to embodiment 2. The control operation of the automatic control device in embodiment 2 will be described with reference to Fig. 5. The procedure from step S100 to step S170 in Fig. 5 is the same as the procedure from step S100 to step S170 in Fig. 2, and therefore repeated explanations will be omitted.

[0034] When the output of the miscellaneous gas sensor 1 is determined to be saturated (step S170: Yes), the control unit 2 compares the current output of the miscellaneous gas sensor 1 with the current output of the miscellaneous gas sensor 6 (step S300). If the difference between the outputs is equal to or greater than the threshold C3 (step S310: Yes), the control unit 2 determines that there is still room for the indoor air to be purified, and operates the blower 5 at the strong notch via the strong notch operation drive circuit 3 to continue the strong notch operation (step S320). On the other hand, if the difference is less than the threshold C3 (step S310: No), the control unit 2 determines that there is no room for the indoor air to be purified, and switches the blower 5 to the weak notch operation via the weak notch operation drive circuit 4 (step S330). The processes from step S170 to step S330 correspond to the second process.

[0035] After the process of step S320 or the process of step S330 is executed, the procedure proceeds to step S140.

[0036] According to the second embodiment, whether or not there is still room for purification of the air in the first space is determined based on the state quantity of the gas concentration in the second space different from the first space, so that the state quantity of the gas concentration can be adjusted to the amount expected by the user regardless of the time interval of factors that affect the outputs of the miscellaneous gas sensors 1 and 6, improving comfort. Note that although a difference in the outputs of the miscellaneous gas sensors 1 and 6 may occur due to differences in the environments of the first and second spaces, by adjusting the threshold C3, this can be adjusted so that the difference in the environments of the first and second spaces does not become a problem.

[0037] Embodiment 3 Fig. 6 is a block diagram showing the configuration of an automatic control device according to embodiment 3. In embodiment 3, whether to perform the control of steps S180 to S210 in embodiment 1 or the control of steps S300 to S330 in embodiment 2 is determined depending on the number of people entering the first space, which is a room where the state quantity of gas concentration is detected by the miscellaneous gas sensor 1. The other configuration is the same as in embodiment 1 and embodiment 2, so duplicated explanations will be omitted.

[0038] As shown in Fig. 6, the automatic control device of the third embodiment is additionally provided with an entry detection unit 7. The entry detection unit 7 detects the number of people entering the room where the state quantity of gas concentration is being detected by the miscellaneous gas sensor 1. The entry detection unit 7 may be, for example, a human sensor that detects infrared rays emitted by the human body, and the control unit 2 is connected to the human sensor via a wired or wireless connection to obtain a signal output by the human sensor. Other methods include obtaining information on the opening and closing of doors and locks, obtaining information from a surveillance camera, and obtaining operation information for lighting or air conditioning by connecting to an IoT (Internet of Things) network.

[0039] Fig. 7 is a flowchart showing the operation procedure of the control unit 2 of the automatic control device according to the third embodiment. The control operation of the automatic control device in the third embodiment will be described with reference to Fig. 7. The procedures from step S100 to step S170 and from step S300 to step S330 in Fig. 7 are the same as the procedures from step S100 to step S170 and from step S300 to step S330 in Fig. 5, and therefore overlapping descriptions will be omitted. In Fig. 7, the control method of the second embodiment is applied, but the control method of the first embodiment may also be applied.

[0040] When the output of the miscellaneous gas sensor 1 is determined to be saturated (step S170: Yes), the control unit 2 determines whether the number of entries detected by the entry detection unit 7 is equal to or greater than the threshold C4 (step S400). When the number of entries is equal to or greater than the threshold C4 (step S400: Yes), the control unit 2 determines that the indoor air needs to be purified until there is no more room to purify, and executes the above-mentioned control from step S300 to step S330.

[0041] On the other hand, if the number of entries is less than threshold C4 (step S400: No), the control unit 2 determines that the indoor air does not need to be purified regardless of whether there is room for purification, and switches the blower 5 to weak notch operation via the weak notch operation drive circuit 4 (step S330). The processes in steps S170 and S300 to S330 correspond to the second process.

[0042] Thus, according to embodiment 3, even if there is still room for the air in the room to be purified, if no or very few people enter the room, a situation in which a person who has been in a weak-smelling atmosphere enters a strong-smelling atmosphere and feels uncomfortable because they have not adapted to the odor will not occur or will occur very rarely, so the strong notch will not be switched over and energy saving will be prioritized.

[0043] In the above, whether or not to perform control is determined depending on whether the number of entries is greater than or equal to threshold C4, but the control method for the controlled object may also be determined based on the entry frequency, which is the number of entries per single period of time.

[0044] The configurations shown in the above embodiments are examples of the contents of the present disclosure, and may be combined with other known technologies, and parts of the configurations may be omitted or modified without departing from the gist of the present disclosure. [Explanation of symbols]

[0045] 1, 6 miscellaneous gas sensor, 2 control unit, 3 strong notch operation drive circuit, 4 weak notch operation drive circuit, 5 blower, 7 entry detection unit.

Claims

1. An automatic control device for controlling a ventilation machine that ventilates a first space that is a room, A first detection unit that detects and outputs a state quantity of the airborne substance in the first space; a control unit that performs a first operation of feedback-controlling the ventilation machine so that an output of the first detection unit is smaller than a target value; Equipped with The control unit is performing a first process for determining whether or not the output of the first detection unit is in a saturated state within a first range for a second time or more when a first time has elapsed since the start of the first operation and the output of the first detection unit is greater than the target value; When it is determined that the output of the first detection unit is in the saturated state, a difference between the output of the first detection unit and a first reference value is calculated, and when the difference is greater than a first threshold value, the first operation is continued, and when the difference is smaller than the first threshold value, a second process is performed to stop the first operation. An automatic control device comprising:

2. The first reference value is a value based on a past output of the first detection unit that has been stored.

2. The automatic control device according to claim 1 .

3. The first reference value is the smallest value among the past outputs of the first detection unit that have been stored.

3. The automatic control device according to claim 2.

4. The first reference value is an output of a second detection unit that is provided in a second space different from the first space and detects and outputs a state quantity of an airborne substance in the second space.

2. The automatic control device according to claim 1 .

5. A third detection unit that detects and outputs the number of times a person enters the first space, the control unit, when determining that the output of the first detection unit is in the saturated state, determines whether or not the output of the third detection unit is greater than a second threshold value, and, when the output of the third detection unit is greater than the second threshold value, calculates a difference between the output of the first detection unit and the first reference value; When the output of the third detection unit is greater than the second threshold value and the difference is greater than the first threshold value, the first operation is continued; When the output of the third detection unit is greater than the second threshold value and the difference is smaller than the first threshold value, the first operation is stopped.

5. An automatic control device according to claim 1, wherein the automatic control device is a control device for controlling a vehicle.

Images