JPH0219381B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to improvements in bypass air volume control in variable air volume type air conditioning equipment that uses a throttle-type VAV unit with a constant air volume function. [Prior Art] Normally, in variable air volume type air conditioning equipment that uses a throttle-type VAV unit, the air flow rate of the air conditioner is In order to prevent the surging phenomenon of the blower and the increase in the noise generated by the VAV unit due to the increase in the static pressure in the duct, especially when the air flow rate decreases, the number of revolutions of the blower should be controlled and input vents or output dampers should be used. It is common to perform blower control that changes the blower characteristics. However, in direct expansion type air conditioners that do not control the refrigerator in proportion to the air conditioning load, if the air flow rate decreases, low pressure cutting of the refrigerator or refrigerator chatter will occur, leading to refrigerator failure. Air flow cannot be drastically reduced. In variable air volume type air conditioning equipment that uses this type of air conditioner, a so-called bypass system is adopted in which a portion of the air volume is returned directly to the air conditioner, so as not to reduce the air volume of the air conditioner itself. The air flow rate is not controlled. A method of controlling the air volume that returns part of the air flow directly to the air conditioner, that is, a bypass air volume control method, is as follows:
A branch duct is installed in the middle of the air supply duct that connects the air conditioner and the VAV unit.
It is connected in the middle of the return air duct that leads return air from the room to the air conditioner. An air volume adjustment damper that adjusts the bypass air volume is installed in the middle of this branch duct, and by controlling the opening degree of this air volume adjustment damper, the VAV unit reduces the indoor air supply amount according to the decrease in the indoor load. A common method is to return surplus air to the air conditioner in proportion to the air volume. The opening degree control of the above-mentioned air volume adjustment damper using conventional technology detects the pressure inside the air supply duct with a pressure detector installed in the middle of the air supply duct, and adjusts the pressure inside the air supply duct to the set value after construction. , which adjusts the opening degree of the air volume adjustment damper. Alternatively, a spring or the like is installed in the air volume adjustment damper itself to maintain a constant pressure difference between the upstream side and the downstream side of the air volume adjustment damper. In these methods, the relationship between the damper opening degree and the pressure inside the air supply duct is not a temporary one, but a very delicate one, which tends to cause hunting and cannot necessarily be controlled reliably. Furthermore, these methods have the following disadvantages because the pressure must be set to a level necessary to convey the necessary amount of air to each outlet when the maximum room air is supplied. (a) The maximum required static pressure to convey the required air volume from the air conditioner to each outlet is not determined at the time of design, but can only be determined after construction because it is affected by the construction method. However, measurements cannot be taken after construction, and decisions must be made through trial and error while checking the blowout condition. (b) If the indoor air supply air volume is reduced in order to keep the pressure inside the air supply duct constant, the pressure required for blowing air will decrease, resulting in excess pressure, and the VAV unit will only pass the required air volume. In addition, the VAV unit has an internal resistance corresponding to the excess pressure, and as a result, the noise generated by the VAV unit increases significantly. (c) Since the noise generated by the VAV unit is large, it is necessary to install a sound deadening box, and in order to add the air blowing capacity equivalent to the pressure loss of this sound deadening box from the design stage, the blowing power will be increased. (d) Since the change in air volume is very large in response to a change in pressure, a highly accurate pressure detector is required, a so-called micro-pressure gauge is required, and this micro-pressure is very expensive and increases the price of the entire device. and lose economic effectiveness. Air conditioning equipment with a variable air volume control method that performs bypass air volume control is originally intended to perform individual control without increasing equipment costs, but with conventional bypass air volume control technology, the above-mentioned Not only are there many problems, but the equipment cost cannot be reduced to the extent desired, the controllability itself is unsatisfactory, and furthermore, there are drawbacks such as an increase in blowing power already at the time of design. For this reason, it is not often practiced at present. [Object of the Invention] The present invention was made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a variable air volume type air conditioning equipment using bypass air volume control simply and inexpensively. [Features of the Invention] A feature of the present invention is that all the installed variable air volume devices, so-called VAV devices,
Bypass air volume is controlled so that an air volume equal to the air volume corresponding to the load of the air conditioning zone communicating with the VAV equipment passes through, and the throttle valve of at least one VAV equipment is fully open among all the installed VAV equipment. The purpose is to adjust the opening degree of the device. This means keeping the air blowing pressure necessary to supply each air conditioning zone with the air volume required by each air conditioning zone to a minimum, and controlling the pressure inside the duct to the minimum while ensuring the required air volume. It means. In other words, all VAV equipment satisfies the required air volume,
In addition, the fact that the throttle valve of at least one of the VAV devices is fully open means that the throttle valve of the VAV device that communicates with the air conditioning zone where the pressure loss is maximum is supplying the required air volume from the blower to each air conditioning zone. This is because it is fully opened and this is the minimum blowing pressure to supply the required air volume. By controlling in this way, the problems of the prior art can be solved as follows. (a) Since each VAV device connected to each air conditioning zone is the control standard, the information obtained here includes all information such as ductwork, and control can be realized without post-construction adjustment work. (b) To minimize the pressure inside the duct,
The noise generated by the VAV device can be minimized, and the amount of leakage from the duct can be minimized. (c) Since the noise generated by the VAV equipment is small, the specific importance of noise countermeasures is small, and the pressure loss up to the air conditioning zone where the maximum pressure loss is expected at the time of design is reduced by fully opening the throttle valve of the VAV equipment that communicates with that zone. Therefore, there is no need to expect extra resistance loss, and installing this equipment does not involve an increase in blowing power. (d) As mentioned above, since the conventional problems and hassles after construction can be solved, the equipment cost for implementing this equipment is much lower than before, and individual control can be achieved at the desired low equipment cost. can be realized. As described above, the present invention uses a direct expansion type air conditioner that does not perform proportional control of the refrigerator, which was previously considered difficult, and simplifies air conditioning equipment that performs individual control by installing a throttle type VAV device. It is designed to be able to be implemented easily and at low cost. [Description of Embodiment] An embodiment of the air conditioning equipment according to the present invention will be described in detail below with reference to FIGS. 1 to 8 of the accompanying drawings. As shown in FIG. 1, the air conditioning equipment of this embodiment includes an air supply duct 11 for supplying air for conditioning from an air conditioner 1. As shown in FIG. This air supply duct 11 is connected to each branch duct 9a, in order to distribute air conditioning air to each air conditioning zone 10a, 10b, 10c.
It is connected to 9b and 9c. Each branch duct 9
A, 9b, and 9c are installed with throttle type variable air volume devices, so-called VAV devices 2a, 2b, and 2c. The air-conditioning air that has passed through the VAV devices 2a, 2b, 2c is supplied to each outlet 13a, 13b, 13c installed at the terminal of the branch duct 9a, 9b, 9c.
Air is supplied from the air to each air conditioning zone 10a, 10b, 10c. Room thermostats 12a, 1 for detecting air conditioning loads are installed in each air conditioning zone 10a, 10b, 10c.
2b, 12c are installed, and each air conditioning zone 10a,
VAV devices 2a, 2b, communicating with 10b, 10c,
2c, each air conditioning zone 10a, 10b,
In response to increases and decreases in air conditioning load of 10c, each VAV2a,
2b and 2c control the air conditioning zones 10a, 10b, and 10 by adjusting the amount of passing air for air conditioning.
Control the room temperature of c. On the other hand, the return air from each air conditioning zone 10a, 10b, 10c is
Suction ports 14a, 14b, 14 installed in c
Return air ducts 15a, 15 connected from c to each
b, 15c, and the main return air duct 5 where they join together to return air to the air conditioner 1. A bypass duct 4 connects the supply air duct 11 and the main return air duct 5 in the middle, and an air volume adjustment damper 6 for bypass air volume adjustment is installed in the bypass duct 4. The air volume adjusting damper 6 performs closing/opening movements in response to signals from the damper controller 20 to control the bypass air volume. Further, this air volume adjustment damper 6 moves to the second position where the damper air volume is closed when there is a maximum input of the control signal from the damper controller 20, and moves to the first position which is the maximum open position when there is a minimum input. move to position. In addition, each of the above-mentioned VAV units 2a, 2b, 2
c controls the amount of passing air to a desired value and transmits information indicating the current control state to the damper controller 20. That is, based on the control status of each VAV unit 2a, 2b, 2c, the damper controller 20 outputs a control signal, and the air volume adjustment damper 6 controls the damper opening degree in accordance with this control output. The air volume is now controlled. Next, each VAV device 2a, 2b, 2c will be explained. Since these VAV devices 2a, 2b, and 2c have the same configuration, in the following explanation, only the first VAV device 2a will be explained as a representative, and explanations of the other VAV devices 2b and 2c will be omitted. As shown in FIG. 2, the first VAV device 2a has a unit duct 40. As shown in FIG. Air sent from the air conditioner 1 flows in the unit duct 40 from one opening to the other opening in the direction of the arrow shown in the figure. An air volume detector 42 is disposed on the upstream side of the unit duct 40. This air volume detector 42
detects the flow rate of air flowing through the unit duct 40, and outputs an actual air volume signal having the detected flow rate information to the corresponding control device 2aa. This air volume detector 42 is rotatably provided approximately at the center of the unit duct 40, and includes a propeller 44 whose rotational speed changes depending on the wind speed, and a rotational speed detection element that detects the rotational speed of the propeller 44. 46. With this configuration, the wind speed of the air flowing through the unit duct 40 can be detected, and therefore the flow rate of the air can be indirectly detected. A throttle valve 48 is disposed on the downstream side of the unit duct 40 in order to throttle the flow path of air passing through the unit duct 40. This throttle valve 48 is composed of, for example, a plate valve, and is driven by a drive mechanism 50. The throttle valve 48 has a driven shaft 52 in the center thereof that extends horizontally and extends in a direction perpendicular to the air flow direction. The throttle valve 48 is rotatably supported around the driven shaft 52, and is at a position inclined at an angle of approximately 60° with respect to the horizontal direction (as shown by the solid line in FIG. 2).
100% of the air flow inside the unit duct 40 is blocked, and the unit duct 40 is placed in a substantially horizontal position (indicated by the two-dot chain line in Fig. 2).
It is designed to allow 100% air circulation. In addition, at a predetermined position on the inner surface of the unit duct 40, when the throttle valve 48 is in the flow blocking position,
A pair of stoppers 54 that come into contact with both upper and lower end surfaces of the throttle valve 48 are attached. A drive mechanism 50 that drives the throttle valve 48 includes a motor 56 that can rotate in forward and reverse directions. This motor 56 is equipped with a gear head 58 having a speed reduction function. From this gear head 58, the motor 56
A drive shaft 60 that rotates by the driving force of is protruded. This drive shaft 60 has a rotation axis along the direction of air flow within the unit duct 40. A worm 62 is attached to the tip of the drive shaft 60 coaxially therewith. A worm wheel 64 meshes with the worm 62. This worm wheel 64 is fixedly attached to one end of the driven shaft 52 coaxially therewith. This motor 56 is driven and controlled by the control device 2aa. A pair of detectors 66 and 68 are arranged at predetermined positions around the worm wheel 64 with a predetermined distance from each other. One detector 66 is a fully open position detector that detects when the throttle valve 48 is in a fully open state, that is, in a state where the pressure loss experienced by the air passing through the throttle valve 48 is minimal. The other detector 68 is a fully closed position detector that detects that the throttle valve 48 is in a fully closed state. These detectors 6
A limit switch or a reed switch is suitable for 6 and 68. Here, the fully open position of the throttle valve 48 does not mean that it is in a substantially horizontal position, as described above, but rather indicates a position in which it assumes a posture that defines the maximum opening area set in the unit duct 40. It is. This control device 2aa is configured as shown in detail in FIG. 3, and according to the logic shown in Table 1,
Each output A or output B is “H” or “L”
Outputs level signal. In Table 1, the symbol P
is the information amount of the actual air volume signal mentioned above, and is denoted by the symbol T
The amount of information included in the set air volume signal output from the room thermostat 12a is shown.

[Table] In Figure 3, room thermostat 12a
is the first operational amplifier (hereinafter, operational amplifier is simply referred to as
It is connected to the non-inverting input terminal of 78 (abbreviated as OP amplifier). The inverse input terminal of this first OP amplifier 78 is connected to its output terminal. 1st
The output terminal of the OR amplifier 78 is connected to the inverting input terminal of the second OP amplifier 82 via a resistor 80.
and to the non-inverting input terminal of a fourth OP amplifier 88 via a resistor 86, respectively. The inverting input terminal of the second OP amplifier 82 and its output terminal are connected to each other via a resistor 90. Resistors 80 and 90 are the second OP amplifier 8
2 negative feedback loops are formed. On the other hand, the airflow detector 42 is connected to the fifth OP amplifier 9.
2 non-inverting input terminal. This fifth
The inverting input terminal of the OP amplifier 92 is connected to its output terminal. The output terminal of the fifth OP amplifier 8 is connected to the second OP amplifier 82 via a resistor 94.
to the non-inverting input terminal of the third OP amplifier 84 and to the inverting input terminal of the third OP amplifier 84 as well as to the fourth
Each is connected to the inverting input terminal of the OP amplifier 88. The inverting input terminal of the fourth OP amplifier 88 and its output terminal are connected to each other via a resistor 98. Resistors 96 and 98 are the fourth
It forms a negative feedback loop circuit for the OP amplifier 88. The output terminal of the third OP amplifier 84 is connected to a resistor 10
0 through the first bilateral switch 102
is connected to the input terminal of This third OP amplifier 84 functions as a comparator, and outputs "H" when a signal with a higher level than the inverting input terminal is input to the non-inverting input terminal, and outputs "L" in the opposite case. . In other words, the third OP amplifier 84 receives the set air volume signal T from the room thermostat 12a.
is larger than the actual air volume signal P, outputs "H",
When the set air volume signal T from the room thermostat 12a is smaller than the actual air volume signal P, "L" is output. Additionally, the first bilateral switch 102
becomes conductive only when "H" is input to its control input terminal, and outputs "L" or "H" input to its input terminal as is to the next stage. Also, the first bilateral switch 102
When "L" is input to its control input terminal, it becomes non-conductive, and regardless of which "L" or "H" is input to its input terminal, the resistor 164 described later is grounded. Always “L” because
It works in the same way as outputting . The output terminal of the second OP amplifier 82 is a resistor 104
It is connected to the non-inverting input terminal of the sixth OP amplifier 106 via. This 6th OP amp 10
The non-inverting input terminal of 6 has a resistor 1 connected to its output terminal.
It is connected via 08. On the other hand, the fourth OP
An output terminal of the amplifier 88 is connected to a non-inverting input terminal of a seventh OP amplifier 112 via a resistor 110. The non-inverting input terminal of this seventh OP amplifier 112 is connected to its output terminal via a resistor 114. 6th and 7th OP amplifier 1
A common DC power supply 116 having a predetermined output voltage is connected to the inverting input terminals of the input terminals 06 and 112, respectively. The output terminal of the sixth OP amplifier 106 is connected to one input terminal of the throttle valve closing drive circuit 118 and the first OR gate circuit 120.
The output terminal of the seventh OP amplifier 112 is connected to the other input terminal of the throttle valve opening drive circuit 122 and the first OR gate circuit 120. The throttle valve closing drive circuit 118 drives the motor 56 so that the throttle valve 48 further closes the unit duct 40 only when "H" is input thereto. Further, the throttle valve opening drive circuit 122 drives the motor 50 so that the throttle valve 48 further opens the unit duct 40 only when "H" is input thereto.
Note that both circuits 118 and 122 stop driving the motor 56 when "L" is applied to them.
The throttle valve 48 is held in that position. first
The output terminal of the OR gate circuit 120 is connected to the input terminal of a second bilateral switch 126 via a resistor 124. This second bilateral switch 126 is constructed similarly to the first bilateral switch 102 described above. Here, the first and fifth OP amplifiers 78, 92
functions as a voltage follower and outputs the input signal to the next stage with an amplification degree of 1. second or fourth
The OP amplifiers 82 and 88 function as differential amplifiers, amplify the potential difference between the two input terminals according to the ratio of the resistors 80 and 90 or the resistors 96 and 98, and output the amplified amplification to the next stage. For example, if we focus on the second OP amplifier 82, this is the fifth OP amplifier 9.
When the output of the second OP amplifier 78 is higher than the output of the first OP amplifier 78, the difference is amplified and output. On the other hand, the fifth
When the output of the first OP amplifier 92 is lower than the output of the first OP amplifier 78, the second OP amplifier 82 outputs a zero potential. On the other hand, focusing on the fourth OP amplifier 88, it outputs a zero potential when the output of the fifth OP amplifier 92 is higher than the output of the first OP amplifier 78, and outputs an amplified potential when it is lower. 6th or 7th OP amplifier 106, 112
functions as a comparator with hysteresis. The sixth OP amplifier 106 outputs "H" when the input voltage from the second OP amplifier 82 is higher than a predetermined voltage obtained by dividing the voltage between the DC power supply 116 and zero potential using resistors 127a and 127b. When it is low, it outputs "L". Further, the fourth OP amplifier 112 is configured so that the input voltage from the fourth OP amplifier 88 flows through the current power source 11.
When the voltage is higher than the predetermined voltage obtained by dividing the voltage between 6 and zero potential using resistors 127a and 127b, it outputs "H",
Outputs “L” when low. However, as mentioned above, the sixth and seventh OP amplifiers 106 and 112 function as comparators with hysteresis, so in order to output from "H" to "L", the DC power supply
From the predetermined voltage obtained by dividing the voltage between 16 and zero potential using resistors 127a and 127b,
2 or the input voltage from the fourth OP amp 88 must be lowered by a potential difference determined by the ratio of resistors 104 and 108 or the ratio of resistors 110 and 114. The OR gate circuit 120 outputs "L" only when "L" is output from the sixth and seventh OP amplifiers 106, 112, and either one of the OP amplifiers 106, 112 is "H". Sometimes it outputs "H". In other words, room thermostat 1
The OR gate circuit 120 outputs "L" only when the set air volume signal T from 2a and the actual air volume signal P are equal, and outputs "H" when they are not equal. Here, the sixth and seventh OP amplifiers 106 and 112
To prevent "H" from being output at the same time, resistor 1
The ratio of resistors 04 and 108, the ratio of resistors 110 and 114, and the ratio of resistors 127a and 127b are set in combination. On the other hand, in addition to the DC power supply 116 described above, another DC power supply 128 is provided. Other DC power supply 1
28 includes first and second output terminals. The first output terminal is connected to the input terminal of a third bilateral switch 132 via a resistor 130, and the lead switch 6 as a fully open position detector.
6 and one end of a lead switch 68 as a fully closed position detector. The other end of the lead switch 66 is connected to a motor stop circuit 134 and a control input terminal of a third bilateral switch 132. This motor stop circuit 134 is
When the reed switch 66 is closed, in other words, when the throttle valve 48 is fully open, the opening operation of the motor 56 is stopped and the reed switch 6 is closed.
8 is closed, that is, when the throttle valve 48 is fully closed, the closing operation drive of the motor 56 is stopped.
Further, the third bilateral switch 132 is
It has the same configuration as the first bilateral switch 102. The power end of the third bilateral switch 132 is grounded via a resistor 136 and connected to the base of an NPN transistor 138. The emitter of this transistor 138 is grounded. The collector of the transistor 138 is connected to the anode of the diode 142, the positive electrode of the electrolytic capacitor 144, and the eighth through the low resistor 140.
The inverting input terminal of the OP amplifier 146 is connected to the inverting input terminal of the OP amplifier 146. The negative electrode of the electrolytic capacitor 144 is grounded. The first output terminal of the other DC power supply 128 is connected to the anode of the diode 142 described above via a resistor 148. The cathode of the diode 142 is connected to the non-inverting input terminal of the eighth OP amplifier 146 and is grounded via a resistor 150. The second output terminal of the other DC power supply 128 is connected to the non-inverting input terminal of the eighth OP amplifier 146 via a resistor 152. This eighth OP amplifier 146 functions as a comparator,
When a voltage higher than the inverting input terminal is applied to the non-inverting input terminal, "H" is output, and when a lower voltage is applied, "L" is output. The output terminal of the eighth OP amplifier 146 is connected to the first and second bilateral switches 102 and 126.
is connected to the control input terminal of Here, when the reed switch 66 is closed, the motor 56 is locked and a voltage is applied to the control input terminal of the third bilateral switch 132. Becomes conductive. As a result, a bias current flows from the DC power supply 128 to the transistor 138 via the resistor 130, and the transistor 138 is turned on. Therefore, the electric charge charged in the electrolytic capacitor 144 is transferred to the resistor 140 and the transistor 13.
8. As a result, a voltage obtained by dividing the output voltage from the second output terminal of the other DC power supply 128 by the resistors 150 and 152 is applied to the non-inverting input terminal of the eighth OR amplifier 146.
On the other hand, since the inverting input terminal of the eighth OP amplifier 146 is connected between the discharging electrolytic capacitor 144 and the resistor 148, a higher voltage is applied to the non-inverting input terminal than the inverting input terminal. Become. In this manner, when the reed switch 66 is closed, the eighth OP amplifier 146 outputs "H". Also, when the reed switch 66 is opened, the third
Since no voltage is applied to the control input terminal of the third bilateral switch 132, the third bilateral switch 132 becomes non-conductive. Therefore, no bias voltage is applied to the base of the transistor 138, and the transistor 138 becomes inactive. For this reason, the electrolytic capacitor 14
4 interrupts the discharge and is charged via the resistor 148 by the output voltage from the first output terminal of the DC power supply 128. When charging of the electrolytic capacitor 144 is completed after a predetermined period of time, the eighth OP
A lower voltage will be applied to the non-inverting input terminal of amplifier 146 than to the inverting input. In this way, when the reed switch 66 is opened, the eighth
The OP amplifier 146 outputs "L". In this way, the eighth OP amplifier 146 outputs "H" when the throttle valve 48 is fully open, and outputs "L" when it is not fully open. Therefore, the first and second bilateral switches 102, 126 are connected to the throttle valve 4.
8 was fully open, and the “H” input to this,
Alternatively, even if "L" is output as is, and "H" or "L" is input to this in a state that is not fully open, the resistors 164 and 166, which will be described later, are grounded, so a constant "L" will always be output. It works in the same way as what is being output. This first and second bilateral switch 1
The output terminals of 02 and 126 are the first and second output terminals, respectively.
is connected to the anodes of diodes 154 and 156. and the first and second diodes 1
The cathodes 54 and 156 are output A and output B, respectively. In this way, the logic shown in Table 1 is realized. The output line groups of output A and output B of the VAV devices 2a, 2b, and 2c are bundled according to the "wired or" configuration, respectively, and are connected to a common damper controller 2.
Connected to 0. This "wired or" configuration means that when multiple output lines are bundled, if at least one output line "H" is output before binding, the other "L" will be ignored and the final “H”
The configuration is such that it outputs . However, when all the output lines before bundling are outputting "L", "L" is finally output. Next, details of the damper controller 20 will be explained using FIG. 4. The damper controller 20 outputs a control signal for controlling the air volume adjusting damper 6 based on the "H" and/or "L" level signals from the outputs A and B, according to the logic shown in Table 2.

[Table] Output A shown in FIG. 4 is connected to input terminal D of first D-type flip-flop 160, and output B is connected to input terminal D of second D-type flip-flop 162. Here, each connection line is grounded via resistors 164 and 166. 1st
The first output terminal Q of the flip-flop 160 is
Second OR gate circuit 1 with five input terminals
68, one input terminal of the first AND gate circuit 170, and one input terminal of the second AND gate circuit 172, respectively. In addition, the first flip-flop 16
The second output terminal of 0 is connected to the first input terminal of a third OR gate circuit 174 having five input terminals. On the other hand, the first output terminal Q of the second flip-flop circuit 162 is connected to the other input terminal of the second AND gate circuit 172, and the second output terminal is connected to the other input terminal of the first AND gate circuit 170. , are connected to each other. 1st AND
The output terminal of the gate circuit 170 is connected to the second and third gate circuits.
The respective second OR gate circuits 168 and 174
is connected to the input terminal of The output terminal of the second AND gate circuit 172 is connected to the third input terminal of the second RO gate circuit 168 and the third input terminal of the third RO gate circuit 174 via the inverter 176, respectively. has been done. The damper controller 20 includes a clock generator circuit 178. This clock generator circuit 178 has a timer function.
IC180, two resistors 182, 184 and two capacitors 18 connected to this IC180
6,188. These resistors 18
By appropriately selecting the values of capacitors 186 and 188, the pulse width and frequency of the clock pulse output from the clock output terminal 3 of the IC 180 are defined. The clock output terminal 3 of this IC 180 is the clock input terminal of each of the first and second flip-flops 160 and 162.
CLK, second and third OR gate circuits 168,
174, respectively. The aforementioned second and third OR gate circuits 16
The output terminals of 8 and 174 are connected to the first up/down counter 194, a countdown input terminal e, and a countup input terminal f, respectively. This first up/down counter 19
4 is composed of a so-called presettable and synchronous up/down 4-bit counter IC, and when combined with the second up/down counter 196, forms an 8-bit up/down counter. That is, the carry output terminal g and the borrow output terminal h of the first up/down counter 194 are connected to the count up input terminal f and the count down input terminal e of the second up/down counter 196, respectively. Further, the clearing input terminals i of both counters 194 and 196 are connected to each other and grounded. First up/down counter 19
The first, second, and fourth preset input terminals a, b, and d of 4 and the second preset input terminal b of the second up/down counter 196 are each grounded. Each up/down counter 194, 196 is
The value of the digital quantity to be output is decreased according to the number of pulses input to the count-down input terminal e, and the value of the digital quantity to be output is increased according to the number of pulses input to the count-up input terminal f. In addition, each up/down counter 194, 196 is currently outputting when no pulse is output to the counter-down input terminal e and the count-up input terminal f, that is, when a constant level signal is input. Holds and outputs digital quantities. The first to fourth output terminals j, k, l, and m of the first up/down counter 194 sequentially define the first to fourth digits of the 8-bit digital quantity, and are respectively It is connected to the first to fourth input terminals. The first to fourth output terminals j of the second up/down counter 196,
k, l, and m sequentially define the 5th to 8th digits of an 8-bit digital quantity, and are connected to the 5th to 8th input terminals of the D/A converter 198, respectively. This D/A converter 198 is a circuit for converting an input digital quantity into an analog quantity, and when 00000000 is input, 0
(DCVolt), and when 11111111 is input, outputs 10 (DCVolt), and 0 to 10 (DCVolt)
DC voltage is output in proportion to the 8-bit digital quantity within the range of . The output terminal of this D/A converter 198 is connected to the non-inverting input terminal of the ninth OP amplifier 200. This 9th OP amp 20
The output terminal of 0 is connected to its own inverting input terminal, and is also connected to the input terminal of the air volume adjustment damper 6. That is, the output terminal from the ninth OP amplifier 200 is defined as the output terminal of the damper controller 20. This damper controller 20 has a DC power supply 20.
2 are connected. That is, the output terminal of the DC power supply 202 is connected to the third preset input terminal c of the first up/down counter 194 via the resistor 202 to the IC of the clock generator circuit 178.
The clear input terminal CLR of the first flip-flop 160 and the preset input terminal of the second flip-flop 162 are connected to the reset terminal 4 and the Vcc terminal 8 of the flip-flop 180 through a common resistor 206.
Ps, and to the first, third, and fourth preset input terminals a, c, and d of the second up/down counter 196 via a common resistor 208, respectively. Therefore, when the power is turned on, "H" is output to the clear input terminal CLR of the first flip-flop 160 and the preset input terminal Ps of the second flip-flop 162, respectively. The damper controller 20 also includes a lower limiter circuit 210 and an upper limiter circuit 210.
is connected. That is, the lower limiter circuit 21
At 0, the first up/down counter 1
The second to fourth output terminals k, l, m of the 94 and the first to fourth output terminals j, k, l, m of the second up/down counter 196 are connected to the first switch circuit 214, respectively. It is connected to second to eighth input terminals of a first NAND gate circuit 216 having eight input terminals. Although the details are not shown, the first switch circuit 214 has an inverter and an ON-
It has an OFF switch connected in series.
Further, the first input terminal of the first NAND gate circuit 216 is connected to the second input terminal.
The output terminal of the first NAND gate circuit 216 is connected to the fifth input terminal of the second OR gate circuit 168 via an inverter 218. With such a configuration, the lower limiter circuit 2
10 has a function of stopping further countdown when the counter counts down to a predetermined value set by the first switch circuit 214. For example, all switches in the first switch circuit 214
When brought to the ON state, the lower limit limiter circuit 210 stops the countdown leaving "00000001". In addition, the first switch circuit 214
If all switches are turned off, the lower limiter circuit 210 will not count down at all. On the other hand, in the upper limiter circuit 212, the second to fourth up/down counters 194
output terminals k, l, m and the first to fourth output terminals j, of the second up/down counter 196,
k, l, m are respectively the second switch circuits 22
0, a second with 8 input terminals
It is connected to the second to eighth input terminals of the NAND gate circuit 222. Second switch circuit 22
0 has an inverter and a changeover switch in each connection line, although details are not shown. That is, each connection line is connected directly to one fixed contact of each changeover switch and to the other fixed contact via an inverter. A movable contact of each changeover switch is connected to a corresponding input terminal of the second NAND gate circuit 222. Also, the second
A first input terminal of the NAND gate circuit 222 is connected to a second input terminal. This second
The output terminal of the NAND gate circuit 222 is connected to the third OR gate circuit 17 via the inverter 224.
The fifth input terminal of 4 is connected to the fifth input terminal. With this configuration, the upper limiter circuit 212
When the count up reaches a predetermined value set by the switch circuit 220, further count up is stopped. For example, the second
When all the switches in the switch circuit 220 are set so that one fixed contact and one movable contact are coupled, the count is increased to "11111110".
Moreover, if all the switches of the second switch circuit 220 are set so that the other fixed contact and the movable contact are coupled, once the countdown has been made to "00000001", the count-up will not be performed at all. Furthermore, a so-called "power-on reset" circuit 226 is connected to the damper controller 20. In this power-on reset circuit 226, the DC power supply 202 is connected to both third AND gate circuits 230 via a variable resistor 228. Additionally, the third AND gate circuit 230
Both input terminals of the on-off switch 23 are grounded via a capacitor 232.
It is grounded via 4. This on-off switch 234 is normally in the OFF state and is provided for manually performing presetting, which will be described later. Note that a third resistor is connected to both ends of the variable resistor 228.
Diode 23 for protection of NAD gate circuit 230
6 are connected in parallel with the cathode connected to the side to which the DC power supply 202 is connected. When the DC power supply 202 is turned off, this diode 236
In order to prevent the voltage stored in the capacitor 232 from acting directly on the third AND circuit 230, the third AND circuit 230 is provided to discharge the voltage stored in the capacitor 232 through this circuit. The output terminal of the third AND gate circuit 230 is connected directly to the preset input terminal Ps of the first flip-flop circuit 160, to the clear input terminal CLR of the second flip-flop circuit 162, and to the first and second up/down counters. To each load input terminal n of 194 and 196,
It is connected via an inverter 238. This "power-on reset" circuit 226 resets the capacitor 23 through a variable resistor 228 when a switch (not shown) of the DC power supply 202 is turned on, that is, when the damper controller 36 is powered on.
Current flows to charge the battery. However, since the current is limited by the variable resistor 228, it takes a predetermined time to complete charging of the capacitor 232. Until this charging, the 3rd
Both input terminals of the AND gate circuit 230 of
“L” is input, and therefore, the third AND gate circuit 230 outputs “L”. That is, "L" is input to the preset input terminal Ps of the first flip-flop 160 and the clear input terminal of the second flip-flop 162 until charging. Therefore, the first flip-flop 160 is
No matter what the input state to the data input terminal D is, "H" is output from the first output terminal Q and the second output terminal of the second flip-flop 162.
"L" is output from the second output terminal Q of the first flip-flop 160 and the first output terminal Q of the second flip-flop 162, respectively. In addition, the first and second up/down counters 19
"H" is input to each of the 4,196 load input terminals n. In this manner, the first and second up/down counters 194, 196 output to the D/A converter 198 in a predetermined preset state for a predetermined period of time until the power-up capacitor 232 is charged. Therefore, since this "power-on reset" circuit 226 is connected,
There is no risk that the damper controller 36 will exhibit irregular behavior peculiar to digital circuits when the power is turned on.
It is always first brought into a constant operating state. Thereafter, when charging of the capacitor 232 is completed, "H" is input to both input terminals of the third AND gate circuit 230, and therefore "H" is output from the output terminal. Therefore, "H" is input to the preset input terminal Ps and the clear input terminal CLR of the first and second flip-flops 160, 162, and both flip-flops 160, 162 are input with "H".
162, in response to the input of a clock pulse to the clock input terminal CLK, the input state to the input terminal D is directly transmitted from the first output terminal Q, and the input state to the input terminal D is inverted and transmitted to the second output terminal. Output each from. In addition, in response to the "H" output of the third AND gate circuit 230, the first and second up/down counters 194 and 196 are released from their predetermined operating states, and the up input terminal f and the down input terminal e It will output a digital amount according to the input state. Next, the steady operating state of the damper controller 36 will be explained with reference to the time charts shown in FIGS. 5A to 5K. First, as shown in FIGS. 5A and 5B, from time t ₁ to t ₂ the first flip-flop 16
Assume that "H" is input to the input terminal D of the second flip-flop 162 (that is, "H" from the output A), and "L" (that is, "L" from the output B) is input to the input terminal D of the second flip-flop 162. Here, a constant clock pulse is inputted to each clock input terminal CLK of the first and second flip-flops 160 and 162 from a clock generator circuit 178 shown in FIG. 5C. Therefore, as shown in FIG. 5D, from the first output terminal Q of the first flip-flop 160,
"H" is output, and "L" is output from the second output terminal as shown in FIG. 5E. Further, as shown in FIG. 5F, "L" is output from the first output terminal Q of the second flip-flop 162, and the second
"H" is output from the output terminal of the circuit as shown in FIG. 5G. Therefore, the first AND gate circuit 17
0, "H" is output as shown in FIG. 5H, and "L" is output from the second AND gate circuit 172 as shown in FIG. 5I. Since "H" is input to at least one input terminal of the second A and fifth OR gate circuits 168, 174, even if a clock pulse is input, both OR gate circuits 168, 174 Figure 5 J
And as shown in FIG. 5K, a constant "H" is output. That is, both up/down counters 194,1
96 holds the output state. In this way, when "H" is output from output A and "L" is output from output B, damper controller 20 does not change the content of the current control output signal. Further, as shown in FIGS. 5A and 5B, from time t ₂ to time t ₃ , the input terminal D of the first flip-flop 160 is set to "L" (that is, from output A to "L"). Assume that "H" is input to the input terminal D of the second flip-flop 16 (that is, "H" from the output B). The first output terminal Q of the first flip-flop 160 outputs "L" as shown in FIG. 5D, and the second output terminal outputs "H" as shown in FIG. 5E. is output. Further, from the first output terminal Q of the second flip-flop 162,
"H" is output as shown in FIG. 5F, and "L" is output from the second output terminal as shown in FIG. 5G. Therefore, the first AND gate circuit 1
70 outputs "L" as shown in FIG. 5H, and the second AND gate circuit 172 also outputs "L" as shown in FIG. 5I. Here, since no signal exhibiting an "H" state other than the clock pulse is input to the input terminal of the second OR gate circuit 168, the second OR gate circuit 168 operates as shown in FIG. 5J. Outputs a clock pulse to On the other hand, the third OR gate circuit 1
Since "H" is input to at least one input terminal of the third OR gate circuit 17, even if a clock pulse is input, the third OR gate circuit 17
4 outputs a constant "H" as shown in FIG. 5K. That is, both up/down counters 194,
196 is brought to a state of countdown.
In this way, when "L" is output from output A and "H" is output from output B, damper controller 20 changes the content of the current control signal so as to decrease. Further, as shown in FIGS. 5A and 5B, from time _t3 to time _t4 , the input terminal D of the first flip-flop 160 is set to "H" (that is, from the output A to "H"). , it is assumed that "H" is input to the input terminal D of the second flip-flop 162 (that is, "H" from the output B). The first output terminal Q of the first flip-flop 160 outputs "H" as shown in FIG.
As shown in Figure E, "L" is output. Also,
The first output terminal Q of the second flip-flop 162
As shown in Figure 5F, "H" is output from
From the second output terminal, as shown in Figure 5G,
“L” is output. Therefore, the first AND gate circuit 170 outputs "L" as shown in FIG. 5H.
is output, and the second AND gate circuit 172 outputs "H" as shown in FIG. 5I. Here, at least one of the second OR gate circuits 168
Since "H" is input to two input terminals,
Even if a clock pulse is input, the second
The OR gate circuit 168 outputs a constant "H" as shown in FIG. 5J. On the other hand, since no signal exhibiting an "H" state other than the clock pulse is input to the input terminal of the third OR gate circuit 174, the third OR gate circuit 174 operates as shown in FIG. 5K. Outputs clock pulse. That is,
Both up/down counters 194, 196 are brought to a counter down state. In this way, when "H" is output from output A and "H" is output from output B, damper controller 20 changes the content of the current control signal so as to increase. Furthermore, as shown in FIGS. 5A and 5B, the time
From time t ₄ to time t ₅ , the input terminal D of the first flip-flop 160 goes "L" (that is, the output A goes to "L"), and the input terminal D of the second flip-flop 162 goes low (that is, the output B goes low). Assume that "L") is input from The first flip-flop 160
As shown in FIG. 5D, from the output terminal Q of
is output, and "H" is output from the second output terminal as shown in FIG. 5E. Further, the first output terminal Q of the second flip-flop 162 outputs "L" as shown in FIG. 5F, and the second output terminal outputs "H" as shown in FIG. 5G. Output. Therefore, the first AND gate circuit 17
0 outputs "L" as shown in FIG. 5H, and the second AND gate circuit 172 outputs the fifth
As shown in Figure I, "L" is output. here,
Since no signal exhibiting an "H" state other than the clock pulse is input to the input terminal of the second OR gate circuit 168, the second OR gate circuit 168
68 outputs a clock pulse as shown in FIG. 5J. On the other hand, since "H" is input to at least one input terminal of the third OR gate circuit 174, even if a clock pulse is input, the third OR gate circuit 174 is As shown in the figure, a constant "H" is output.
That is, both up/down counters 194 and 196
is brought into countdown state. In this manner, damper controller 20 changes the content of the current control signal to decrease. In this way, the logic shown in Table 2 is realized. Here, when "L" is output from output A and "L" is output from output B, as can be easily understood from Table 1, P=T, that is, the amount of information contained in the actual air volume signal and the room thermometer. This is a case in which the amount of information contained in the set air volume signals from the data points is equal to each other. Therefore, originally a "hold" operation must be performed. However, if the "hold" operation is executed in this state, the other output A in Table 1 becomes "L",
When the output B is in the meaning expressed by "L", that is, when the throttle valve 48 is not fully open, it becomes impossible to open the damper device 32 and lead the throttle valve 48 to the fully open state. Therefore, in the above case, the control content is defined as "open". However, if the throttle valve 48 is fully open and the control content continues to be "open", the passing air volume will decrease, so the output will change from "L" to "H".
, output A goes “H”, output B goes “L”
There is an output, which leads to the "hold" state. The operation of the air conditioning equipment having the bypass air volume control device configured as described above will be explained below. First, assume that indoor air supply is stopped. In this case, all VAV devices 2a, 2b, 2
Since the throttle valve 48 of c is in the fully open state, the output of the damper controller 20 is reduced. As a result of the air volume adjustment damper 6 opening in this way,
The bypass duct 4 is in a fully open state. At this time, the supply air volume is completely bypassed. Next, assume that the indoor air supply air volume is set by a room thermostat. At this time, each VAV device opens until the air volume set by the room thermostat 12a and the air volume detected by the air volume sensor 42 (actual air volume) match. In this case, if the set air volume and the air volume detected by the air volume sensor 42 match when the throttle valve 48 of each VAV device 2a, 2b, 2c is not fully open (position between fully open and fully closed), the damper controller 20 Since the output remains at the minimum value, the air volume adjustment damper 6 remains fully open. Next, when the throttle valve 48 of the VAV device is fully open and the air volume detected by the air volume sensor 42 is lower than the set air volume, the damper controller 20 increases the output;
The air volume adjustment damper 6 is moved to close. As a result, the supply air duct 11 and the main return air duct 5
As the resistance between the VAV device 2a and the
The amount of air passing through the VAV device 2a increases. When the air volume detected by the air volume sensor 42 becomes equal to the set air volume, the output of the damper controller 20 stops increasing, and the position of the air volume adjustment damper 6 is maintained in order to maintain the output state. At this time, the output of each branch duct 9a, 9b increases, causing an inconvenience that the amount of air passing through the VAV device communicating with other air conditioning zones increases. However, in this embodiment, each air volume sensor 42 of the VAV devices 2a, 2b, 2c causes the propeller 44 to rotate faster as the volume of air flowing through the corresponding unit duct 40 increases.
Therefore, the signal P indicating the actual air volume from the rotation detection element 46 becomes large. In other words, the actual air volume P is the set air volume T.
becomes larger than Therefore, the throttle valve closing operation circuit 11 is connected via the second and sixth OR amplifiers 82 and 106.
8 is output. Here, "L" is output to the throttle valve opening operation circuit 122. This throttle valve closing operation circuit 118 operates to operate the motor 56 to close the throttle valve as long as the throttle valve 48 is not in the fully closed state, that is, unless the fully closed position detector 68 is turned on and the motor stop circuit 134 is operated. 45 in the direction to close it. As a result, the opening area of each unit duct 40 of the VAV devices 2a, 2b is reduced, and the air volume is reduced. This closing operation of the throttle valve 48 continues until the actual air volume P becomes equal to the set air volume T and "H" is no longer output to the throttle valve closing operation circuit 118 via the second and sixth OP amplifiers 82 and 106. It will be done. Motte VAV device 2a,
2b maintains the air volume passing through each unit duct 40 at a predetermined set air volume. Further, in this embodiment, the VAV device 14,1
Each of the air volume sensors 42 8 and 28 causes the propeller to rotate slowly as the volume of air flowing through the corresponding unit duct 40 decreases. Therefore, the amount indicating the actual airflow rate via the rotation detection element 46 is made small. That is, the actual air volume P becomes smaller than the set air volume T. Therefore, the fourth and seventh OP amplifiers 88,
112, "H" is output to the throttle valve opening operation circuit 122. Here, "L" is output to the throttle valve closing operation circuit 118. The throttle valve opening operation circuit 122 operates the motor 56 to open the throttle valve 48 unless the throttle valve 48 is fully open, that is, unless the fully open position detector 66 is turned on and the motor stop circuit 134 is operated. Rotate it in the direction to open it. This allows the first
The opening area of each unit duct 40 of the third VAV devices 2a, 2b, and 2c is increased, and the air volume is increased. This opening operation of the throttle valve 48 is performed until the actual air volume P becomes equal to the set air volume T. Consequently, the VAV devices 2a, 2b, 2c maintain the air volume passing through each unit duct 40 at a predetermined set air volume. In the above manner, each VAV device 2a, 2
The constant air volume maintenance function in b and 2c is completed. The control process in this damper controller 20 will be explained with reference to the flowchart shown in FIG. The air volume adjustment damper 6 is controlled so that the throttle valve 48 of at least one VAV device is in the fully open position. That is, when the throttle valve 48 of any VAV device is fully open, it means that the amount of passing air is satisfied or insufficient. On the other hand, the fact that the throttle valve 48 of any VAV device is not fully open means that the pressure is in an excessive state. Therefore, in step S1, at least one
It is determined whether the throttle valve 48 of the VAV device is fully open. If it is determined to be “ON” here, that is,
When "L" is output from output A and "L" is output from output B, the air volume adjustment damper 6 is opened and the energy related to indoor air supply through the VAV device, that is, the pressure inside the air supply duct, decreases. The amount of air passing through the VAV devices decreases, and each VAV device opens its respective throttle valve 48 in an attempt to maintain a predetermined amount of air. This control to reduce the bypass air volume by opening the air volume adjustment damper 6 is performed on at least one VAV.
This is continued until it is determined that the throttle valve 48 of the device is fully open. That is, if the determination in step S1 is "YES", the determination in step S2 is executed next. In step S2, it is determined whether the set air volume T is larger than the actual air volume P. Here, “YES”
If it is determined that “H” is output from output A and “H” is output from output B, the air volume adjustment damper will
Closed. This is because this judgment means that the energy, or pressure, required for indoor air supply is insufficient. If it is determined in step S2 that the set airflow rate T is larger than the actual airflow rate P, then the determination in step S3 is performed. In step S3, if it is determined "NO" that the set air volume T is equal to the actual air volume P, the air volume adjustment damper 6 is opened. This is because this judgment means that the energy, or pressure, required for indoor air supply is excessive. Further, in step S3, if it is determined as "YES" that the set air volume T is equal to the actual air volume P, the air volume adjustment damper 6 is maintained at its opening position. This is because the fact that the set air volume T and the actual air volume P are equal through the above process means that the optimal indoor air supply air volume is obtained when the resistance between the air conditioner and the outlet is the lowest. Because there is. In one embodiment as described above, each VAV device 2a,
2b and 2c use an airflow sensor 42 and a throttle valve 8 to automatically control a constant airflow. Therefore,
Each set indoor air supply air volume is accurately guaranteed. Furthermore, as shown as a modification in FIG. 7, the air volume adjustment damper 6 installed to control the bypass air volume can be replaced with an air volume control device 30 with a constant air volume function. At this time, when there is a maximum input from the damper controller 20, the air volume control device 30 with a constant air volume function
The bypass air volume is closed, that is, it is moved to a position where the maximum set air volume of the air volume control device 30 with a constant air volume function is passed when there is a minimum input from the damper controller 20 by closing the bypass air volume until it is fully closed. In other words, the damper controller 20 outputs a control signal based on the control state of each VAV unit 2a, 2b, 2c, and the air volume controller 3 with a constant air volume function appropriately controls the air volume corresponding to the magnitude of this control signal.
0 is bypassed. Note that this invention is not limited to the configuration of the above-described embodiment, and can be modified in various ways without departing from the spirit of the invention. Below, another embodiment of an air conditioner equipped with a bypass air volume control device according to the present invention will be described with reference to FIG. Note that the same parts as those in the above-mentioned embodiment are given the same reference numerals, and the explanation thereof will be omitted. In the embodiment described above, the fully open position of the throttle valve 48 was directly detected by a limit switch or a reed switch. However, without being limited to such a configuration, the eighth
It may be configured as shown in the figure. That is, the fully open position detector 240 has first and second pressure chambers 244 and 24 separated by a diaphragm 242.
The main body 248 has a diameter of 6. The first pressure chamber 244 communicates with a portion of the unit duct 40 upstream of the portion where the throttle valve 48 is provided via a first communication path 250, and communicates with the second pressure chamber 246.
A second communication passage 2 is provided in a part of the unit duct 40 downstream of the part where the throttle valve 48 is provided.
It communicates via 52. This diaphragm 2
A strain gauge 254 is attached to 42. The strain gauge 254 detects the amount of deformation of the diaphragm 242 due to the pressure difference inside the unit duct 40 before and after the throttle valve 48, and outputs an electric signal corresponding to this amount of deformation. That is, by reaching the fully open state of the throttle valve 48, the pressure difference between the first and second pressure chambers 244, 246 is minimized. Therefore, the amount of deformation of the diaphragm 242 depending on this pressure difference is minimized, and this state is detected as a fully open state via the strain gauge 254. Note that the diaphragm 242 in FIG. 8 can be replaced with a piston.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram schematically showing an embodiment of air conditioning equipment according to the present invention, and FIG. 2 is a configuration diagram showing a first VAV.
A side sectional view schematically showing the device, FIG.
Circuit diagram showing the configuration of the control device of the VAV device, No. 4
The figure is a circuit diagram showing the configuration of the damper controller, each of FIGS. 5A to 5K is a timing chart for explaining the operation of the damper controller, and FIG. 6 is a flow chart for explaining the control contents of the damper controller. FIG. 7 is a block diagram schematically showing a modification of the air conditioning equipment, and FIG. 8 is a side sectional view schematically showing an air volume control device used in the air conditioning equipment of another embodiment. 1... Air conditioner, 2a, 2b, 2c... VAV device, 2aa... Control device, 4... Bypass duct,
5... Main return air duct, 6... Air volume adjustment damper, 9a, 9b, 9c... Branch duct, 10a,
10b, 10c...Air conditioning zone, 11...Air supply duct, 12a, 12b, 12c...Room thermostat, 13a, 13b, 13c...Blowout port, 14a, 14b, 14c...Suction port, 15
a, 15b, 15c... Return air duct, 20...
damper controller.

Claims (1)

[Scope of Claims] 1. Air conditioning equipment that supplies air from an air conditioner through a duct, is equipped with a variable air volume device, and is equipped with a bypass air volume control device that bypasses the air conditioning zone and returns excess air directly to the air conditioner. , each air volume control device is installed in each air supply branch duct that connects the air conditioner and the plurality of air conditioning zones, and each of these air volume control devices is equipped with an air volume sensor that detects the amount of air passing through the air volume control device. a throttle valve that is movable between a first position in which the air volume control device is in a maximum open state and a second position in which it is in a fully closed state; a first drive mechanism that drives the throttle valve; A first control mechanism is provided in which the passing air volume can be set and controls the drive device so that the set passing air volume matches the air volume detected by the air volume sensor; A bypass duct is provided in the middle of a main return air duct that passes return air from the air conditioning zone, and a third position in which the bypass duct is placed in a maximum open state and a fourth position in which the bypass duct is in a fully closed state is provided in the middle of this bypass duct. a damper movable between the damper; a second drive mechanism for driving the damper; In an air volume control device in which the damper is moved to open until the valve reaches the first position, and the throttle valve is in the first position, if the air volume detected by the air volume sensor is less than the set air volume, the passing air volume is increased. In an air volume control device in which the damper is moved to close as shown in FIG. 1. An air conditioning equipment comprising: a damper device having a second control mechanism for controlling the air conditioner; 2. Each of the air volume control devices includes a first comparator that outputs a first level signal when the set air volume is smaller than the detected air volume, and a second level signal when the set air volume is larger than the detected air volume, and a first comparator that outputs a second level signal when the set air volume is larger than the detected air volume. A second comparator outputs a first level signal when the set air volume is equal to the detected air volume, and outputs a second level signal when the set air volume is not equal to the detected air volume; When the valve is in the first position, the input signal is output as is, and when the valve is not in the first position, the first level signal is always output.
output means; the second control mechanism includes a logic operation circuit that receives outputs from both output means and outputs a calculation signal; and a logic operation circuit that is connected to the logic operation circuit and operates the damper device according to the calculation signal. a conversion circuit that outputs an instruction signal that defines a damper position;
When receiving a level signal, outputs a calculation signal to open the damper position of the damper device, and when receiving a second level signal from the first output means and a first level signal from the second output means, outputs a calculation signal to open the damper position of the damper device. A calculation signal for maintaining the damper is output, a second level signal is output from the first output means, and a second level signal is output from the second output means.
2. The air conditioning equipment according to claim 1, wherein the air conditioning equipment outputs a calculation signal for closing the damper position of the damper device when receiving the level signal. 3. The conversion circuit includes an up/down counter that outputs a digital amount according to the operation signal of the logic operation circuit, and a D/A that is connected to this up/down counter and outputs an analog amount that corresponds to the digital amount.
3. The air conditioning equipment according to claim 2, further comprising a converter, wherein the damper device defines the opening degree of the damper according to an analog quantity from a D/A converter. 4. The air volume control device includes a power-on reset circuit connected to an up/down counter,
4. The air conditioning equipment according to claim 3, wherein the power-on reset circuit operates an up/down counter and outputs a predetermined digital amount for a predetermined period of time from power-on. 5. The air volume control device includes a countdown limiter circuit and a countup limiter circuit connected to an up/down counter, and the countdown limiter circuit defines a lower limit value of the digital amount output from the up/down counter. 5. The air conditioning equipment according to claim 4, wherein the count up limiter circuit defines an upper limit value of the digital amount output from the up/down counter. 6. The air conditioning equipment according to claim 1, wherein the first control mechanism can be set from the outside at an air volume that is less than or equal to a maximum allowable passing air volume. 7. The air conditioning equipment according to claim 1, wherein the first control mechanism can be set internally at an air volume that is less than or equal to a maximum allowable passing air volume.