JPH0320669B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides capacity control during low loads of absorption type air conditioners, heaters, or air conditioners (hereinafter collectively abbreviated as "absorption type air conditioners and/or heaters"). Regarding.

Capacity control of an absorption type air conditioner and/or heater is usually performed by detecting the temperature of cold water or hot water and proportionally or stepwise controlling the flow rate of the heating source in the regenerator via a temperature controller. If the heating source is gas or oil, the amount of heating is controlled by a fuel control valve and a combustion air control valve, and if steam is used, the amount of heating is controlled by a steam control valve. The lower limit of the amount of heating that can be continuously controlled is
Although it varies slightly depending on the type of heating source, it is approximately 20%.

When the air conditioning load decreases beyond the above control range, the cold water temperature decreases during cooling, the hot water temperature rises during heating, and the air conditioner automatically stops at a certain set temperature. Thereafter, the air conditioner is automatically restarted as the cold water temperature increases or the hot water temperature decreases.

However, when the air-conditioning equipment that has automatically stopped is restarted, the control valve that controls the amount of heating in the regenerator is fully opened based on the signal from the cold water or hot water temperature detection unit. The solution is rapidly heated, and as a result, the temperature of the cold water reaches a predetermined automatic stop temperature in a short period of time, resulting in automatic stop.

Therefore, when the air conditioning load is relatively small, automatic shutdown and restart are repeated frequently, which is undesirable in terms of the lifespan of the solution pump, refrigerant pump, or auxiliary equipment of the air conditioner. In addition, during cooling operation, in order to prevent the solution from crystallizing inside the machine when the machine is stopped, the solution is circulated for a certain period of time to equalize the internal solution concentration, so in the above case, the regenerator A portion of the heat added to the solution is discarded into the cooling water, causing a decrease in efficiency.

An object of the present invention is to provide an absorption type air conditioner and/or heater that prevents the lifespan of pumps and auxiliary equipment from decreasing and improves efficiency during air conditioning by eliminating the drawbacks of the prior art. There is something to do.

That is, to summarize the present invention, the present invention relates to an absorption cooling and/or heating machine comprising an absorber, an evaporator, a regenerator, a condenser, a heat exchanger, and a refrigerant path and a solution path connecting them. , is equipped with a device that detects the cooling or heating load, and an external resistance added to the cold water or hot water temperature control device to compensate for the detected value, and the amount of load detected by the detection device is lower than the set value. When small (at low load)
The present invention is characterized in that a means for controlling the amount of heating by the external resistance is provided.

In the present invention, a cooling or heating load is detected, and when the detected value is relatively small compared to a predetermined capacity of the absorption type cooling and/or heating machine, control is performed to control the amount of heating in the regenerator. By adding an external resistor to the device, a signal is sent to limit the amount of heating.

Hereinafter, the present invention will be specifically explained based on the accompanying drawings.

FIG. 1 is a system diagram of a dual-effect gas absorption type air-conditioning machine that constitutes one embodiment of the present invention.

In Figure 1, 1 is an absorber, 2 is an evaporator, and 3
is a low-temperature regenerator, 4 is a condenser, 5 is a low-temperature heat exchanger,
6 is a high temperature heat exchanger, 7 is a high temperature regenerator, 8 is a solution pump, 9 is a refrigerant pump, 10 is a cold (hot) water pipe,
11 is a cooling water pipe, 12 is a burner, 13 is a gas cutoff valve, 14 is a fan, 15 is a gas flow rate control valve, 1
6 is a combustion air flow control valve, 17 is a gas pipe, 18
is a control motor, 19 to 21 are cold (warm) water temperature detectors, 22 is a cold (warm) water flow rate detector, 23
is an external calculation device, 24 is a temperature controller, 25 and 2
6 is a cold/warm switching valve.

To explain the internal cycle during cooling, the solution is heated from the absorber 1 by the solution pump 8 via the low-temperature heat exchanger 5 and the high-temperature heat exchanger 6, and sent to the high-temperature regenerator 7. It is heated by high-temperature combustion gas, releases refrigerant vapor, concentrates it, exchanges heat with the low-temperature side solution in the high-temperature heat exchanger 6, and flows into the low-temperature regenerator 3. The solution that has flowed into the low-temperature regenerator 3 is heated again by the high-temperature refrigerant vapor generated in the high-temperature regenerator 7, releases the refrigerant and concentrates, exchanges heat with the low-temperature side solution in the low-temperature heat exchanger 5, and then passes through the absorber. Sprayed on the heat exchanger tubes in 1. On the other hand, the refrigerant vapor generated in the low-temperature regenerator 3 and the refrigerant liquid condensed by heat exchange with the solution in the low-temperature regenerator 3 are condensed and cooled by cooling water passing through the condenser 4, and sent to the evaporator 2. .
The refrigerant that has flowed into the evaporator 2 is spread over the heat transfer tubes in the evaporator 2 by the refrigerant pump 9, where it takes heat from the cold water and evaporates, and the vapor flows into the absorber 1 and is spread inside the absorber 1. absorbed into the solution. The heat absorbed when the solution absorbs refrigerant vapor is released to the cooling water passing through the absorber 1. The solution that has absorbed the refrigerant to reduce its concentration is sent again to the high temperature regenerator 7 by the solution pump 8, and the cycle is repeated.

On the other hand, during heating, the cooling/heating switching valves 25 and 26 are opened. The solution circulation route is the same as during cooling.
The solution passes through a low-temperature heat exchanger 5 and a high-temperature heat exchanger 6 by a solution pump 8, is heated by a high-temperature regenerator 7, releases refrigerant vapor, and passes through a high-temperature heat exchanger 6, a low-temperature regenerator 3, and a low-temperature heat exchanger 5. Return to absorber 1. High temperature regenerator 7
The refrigerant vapor generated passes through the cooling/heating switching valve 25,
It flows into the low-pressure side can body, gives heat to the hot water in the evaporator 2, and condenses. The refrigerant condensed in the evaporator 2 passes through the cooling/heating switching valve 26 and moves to the solution side, and the diluted solution is again sent to the high temperature regenerator 7 by the solution pump 8.

The amount of heating in the high temperature regenerator 7 is determined by the cold (warm) water temperature detected by the cold (warm) water temperature detector 20.
The control motor 18 that drives the gas flow rate control valve 15 and the combustion air flow rate control valve 16 is operated and controlled via the temperature regulator 24 .

In the present invention, the cold (warm) water temperature detector 19
21, and the cold (warm) water temperature and cold (warm) water flow rate detected by the cold (warm) water flow rate detector 22 are input to the external calculation device 23, and the cooling load or heating load calculated by the external calculation device 23 is calculated. If it is determined that the current is relatively small compared to the rated capacity value of the air conditioner, the external arithmetic unit 23 issues a low load command, and the output from the cold (hot) water temperature detector 20 to the temperature controller 24 differs from the actual one. By issuing the signal, the opening degree of the control motor 18 is restricted, and the amount of heating in the high temperature regenerator 7 is restricted.

The attached FIG. 2 specifically shows the above control.

That is, FIG. 2 is an electrical circuit diagram of a temperature detection section showing an embodiment of the present invention. The one shown in Fig. 2 uses a resistance temperature detector Rt as the cold water and hot water temperature detector 20, and the temperature controller 2
It is connected to the A and B terminals of 4.

43X is a relay contact that is energized during cooling, RL, HL
are low load commands for cooling and heating, respectively.
(Figure 2 shows a state without command.) R1 and R2 are external resistances.

(During cooling) If a low load command is not issued, the signal from the resistance temperature detector Rt, which is the chilled water temperature detection section, is directly input to the temperature controller 24 and sent to the control motor 18.
control. Low load command from external computing device 23
When RL is output, external resistance R1
Since they are connected in parallel to Rt, the combined resistance value between AB is smaller than the resistance value Rt of the resistance temperature detector, and as a result, the temperature controller 24 is supplied with a temperature △t ₁ lower than the actual temperature. A signal corresponding to is output, the control motor 18 moves in the closing direction, and the amount of heating is reduced.

(During heating) When the low load command HL is issued, the external resistor R2 is connected in series with the resistance temperature detector Rt, so the combined resistance value between AB becomes larger than the resistance value Rt of the resistance temperature detector. A signal corresponding to a temperature Δt ₂ higher than the actual hot water temperature is output to the temperature regulator 24, the control motor 18 moves in the closing direction, and the amount of heating is reduced.

As described above, by adding an external resistance, the amount of heating in the high temperature regenerator 7 is limited by sending a different signal from the actual one to the temperature controller 24, and when the load is low, the high temperature regenerator 7 It is possible to prevent the solution temperature from rising rapidly and reduce the frequency of start and stop.

As the cold water and hot water temperature detectors, a thermistor type sensor may be used instead of the above-mentioned resistance temperature detector. In this case as well, by adding an external resistor, it is possible to send a signal different from the actual signal.

A calorimeter or the temperature difference between the inlet and outlet of cold water, hot water, or air-conditioned water may be used to detect the cooling load and the heating load, and the temperature difference between the outlet and outlet of the cooling water may be used to detect the cooling load.

In addition, in the absorption cooling and/or heating machine according to the present invention, it is preferable that the low load command be ignored for a certain period of time when the absorption type cooling and/or heating machine is started for the first time.

Next, as an embodiment of the present invention, FIG. 3 shows an example in which the cooling load or heating load is detected based on the temperature difference between the inlet and outlet of air-conditioned water.

That is, FIG. 3 is a partial system diagram of an air-conditioning machine in which the cooling or heating load detection device is a device that detects the inlet/outlet temperature and flow rate of air-conditioned water, as an embodiment of the present invention.

In FIG. 3, 1, 2, 10, 20, 23 and 24 have the same meaning as in FIG. 1, 27 is a heat storage tank, 2
8 is an air conditioner, 29 is a cold/hot water circulation pump, 30 is an air conditioned water circulation pump, 31 is an air conditioned water pipe, 32 is an air conditioned water flow rate detector, and 33 and 34 are air conditioned water temperature detectors.

The external calculation device 23 determines the amount of cooling or heating load, and when the load is low, a signal different from the actual one is output to the temperature controller 24.

Further, as an embodiment of the present invention, an example of a single-effect absorption type air conditioner (freezer) is illustrated in FIG.

That is, FIG. 4 is a system diagram of a single-effect absorption refrigerator using steam as a heating source, which is an embodiment of the present invention.

In Figure 4, 1, 2, 4, 8-11 and 1
9 to 24 correspond to the respective symbols in FIG. 1, 35 is a regenerator, 36 is a heat exchanger, and 37 is a steam control valve.

In the absorption refrigerating machine illustrated in FIG.
The temperature of the cold water is detected, and the steam control valve 37 is controlled via the temperature regulator 24 to adjust the amount of heating in the regenerator 35. As described above, an external calculation device determines the amount of cooling load, and when the load is low, a signal different from the actual one is output from the chilled water temperature detector 20 to the temperature controller 24.

Since the control in the present invention only adds external resistance, it can be applied to both single-effect and double-effect absorption cooling and/or heating machines, and can be used for simultaneous cooling and heating. In the case of operation, it is sufficient to provide one more electric circuit as illustrated in FIG.

As explained in detail above, according to the present invention,
When the cooling or heating load is detected and the detected value is relatively small compared to the predetermined capacity of the absorption cooling and/or heating machine, the regenerator is activated by the action of an additionally installed external resistor. By sending a signal to control the amount of heating to the heating amount controller in the system, rapid heating in the regenerator is prevented during low load, and the frequency of automatic start/stop of absorption cooling and/or heating equipment is reduced. This prevents the lifespan of pumps and auxiliary equipment from being shortened, and improves efficiency during cooling.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a dual-effect gas absorption type air-conditioning machine that constitutes one embodiment of the present invention. FIG. 2 is an electrical circuit diagram of a temperature detection section showing an embodiment of the present invention. FIG. 3 is a partial system diagram of an air-conditioning machine in which the cooling or heating load detection device is a device for detecting the inlet/outlet temperature and flow rate of air-conditioned water, which is an embodiment of the present invention. FIG. 4 is a system diagram of a single-effect absorption refrigerator using steam as a heating source, which is an embodiment of the present invention. 1: absorber, 2: evaporator, 3: low temperature regenerator,
4: Condenser, 7: High temperature regenerator, 10: Cold (hot) water pipe, 11: Cooling water pipe, 12: Burner, 18:
Control motor, 19-21: Cold (hot) water temperature detector, 22: Cold (hot) water amount detector, 23: External calculation device, 24: Temperature regulator, R1 and R2:
External resistance, 27: Heat storage tank, 28: Air conditioner, 32:
Air conditioned water flow rate detector, 33 and 34: Air conditioned water temperature detector, 35: Regenerator, 37: Steam control valve.

Claims (1)

[Scope of Claims] 1. In an absorption type air conditioner, heater, or air conditioner consisting of an absorber, evaporator, regenerator, condenser, heat exchanger, and a refrigerant path and a solution path connecting them, A device for detecting a cooling or heating load;
In order to compensate for the detected value, the cold water or hot water temperature control device is equipped with an external resistance added, and when the load amount detected by the detection device is smaller than the set value (during low load), the external resistance is 1. An absorption type air conditioner, heater, or air conditioner, characterized by being provided with means for controlling the amount of heating by using a resistance. 2. The absorption type air conditioner or heater according to claim 1, wherein the cooling or heating load detection device is an external calculation device that receives input/outlet temperature and flow rate of cold water, hot water, or air-conditioned water. , or air conditioner. 3. The absorption type air conditioner, heater, or air conditioner according to claim 1, wherein the cooling load detection device is a device that detects a temperature difference between an inlet and an inlet of cooling water. 4. The absorption type air conditioner, heater, or air conditioner according to claim 1, wherein the cooling or heating load detection device is a resistance temperature sensor or a thermistor type sensor.