JPS6375451A - Overheat preventive device for absorption refrigerator - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] (b) Industrial application field The present invention relates to an overheat prevention device for an absorption refrigerator.

(b) Conventional technology In absorption refrigerators, when the heat input is greater than the heat output, the Iq heat inside the machine accumulates, so if this is left as is, the temperature and pressure inside the generator will increase. begins to rise, and eventually the temperature and pressure become excessively high, causing an abnormal drop in the liquid level inside the generator, leading to dry firing of the generator, crystallization of the solution, or damage to generator components. There is a risk.

Therefore, as a conventional technology for preventing overheating of absorption refrigerators,
A device equipped with a protection device that stops the heating of the generator when the temperature, pressure, or liquid level inside the generator approaches an abnormal value (for example, JP-A-52-9151, JP-A-52- 45757 and Japanese Utility Model Application Publication No. 52-71153) are known.

(c) Problems to be solved by the invention In the conventional system described above, the protection device operates after a considerable period of time has passed after the absorption chiller begins to overheat. There are problems in that this continues unnecessarily, wastefully consuming heat sources such as fuel, and that the components of the generator deteriorate more quickly.

In addition, in the conventional type, before the pressure, temperature, or liquid level in the generator approaches an abnormal value, for example, when the pressure or temperature becomes slightly higher than the rated value, or
A possible method of solving the above problem is to activate the protection device when the liquid level becomes a little X lower than the rated value. However, in absorption refrigerators, even if the heat balance is maintained, the temperature, pressure, and liquid level inside the generator change depending on the load and cooling water temperature conditions.
When the above-mentioned method is adopted, there is a problem in that the protection device is activated frequently even when no overheating occurs. In other words, in the conventional method, it was difficult to appropriately prevent overheating of the absorption refrigerator, and it was not practical.

In view of these problems, the present invention aims to provide a device that can appropriately and reliably prevent overheating of an absorption refrigerator.

(d) Means for Solving the Problems The present invention provides a measuring device for measuring the heat balance of an absorption chiller and a measuring device for measuring the magnitude of heat input and heat output as a means for solving the above-mentioned problems. An overheat prevention device for an absorption chiller consists of a judgment device that performs comparison and discrimination, and a controller that stops heating the generator based on the signal from the judgment device when the heat input exceeds the allowable range and exceeds the heat output. It is something.

(e) Effect In the device of the present invention, the measuring device directly measures the heat balance during operation of the absorption chiller, and at the same time the determining device measures the heat balance at the point when the absorption chiller is overheated, that is, when the heat input starts to exceed the heat output. Since the controller stops heating the generator, it is possible to appropriately and reliably prevent overheating of the absorption refrigerator.

(f) Embodiment FIG. 1 is a schematic structural diagram showing an embodiment of an overheating prevention device for an absorption refrigerator according to the present invention. In Figure 1,
(A) is an absorption refrigerator, which includes a high temperature generator (1), a low temperature generator (2), a condenser (3), and an evaporator (
4), absorber (5), low temperature, high temperature solution heat exchanger (6)
, (7), The refrigerant liquid pump (P,) and the solution pump (PA) are connected to the refrigerant pipe (8), (9), the refrigerant liquid flow pipe (10), the refrigerant liquid return pipe ( 11) , (
12), pipes for dilute solutions (13), (14), pipes for intermediate concentration solutions (15), (16), and pipes for concentrated solutions (17), (1B) to connect the refrigerant [water]. ] and the solution [lithium bromide aqueous solution] form a circulation path.

(19) is the combustion heating chamber of the high temperature generator (1), (20)
, (20)... are combustion gas passages, (21) are the heaters of the low temperature generator (2), (22) are the coolers of the condenser (3), and (23) are the evaporator (4) The heat exchanger (24) is a cooler for the absorber (5). (25> is the combustion heating chamber (1
9), which is equipped with a fuel flow control valve (VF) and a flow rate detector (S□). Although not shown, when steam is used as the heat source of the high temperature generator (1), a flow rate control valve and a flow rate detector are provided in the steam supply path, and temperature control valves and flow rate detectors are provided at the entrance and exit of the high temperature generator (1), respectively. A detector is provided. (26), (27
) and (28) are cooling water pipes in which coolers (24) and (22) are connected in series, and (29) and (3
0) is a cold water pipe connected to a heat exchanger (23).

Further, (STWI) is a temperature detector provided in the cold water pipe (29), and (sr□), (S, yx) are temperature detectors and flow rate detectors provided in the cold water pipe (30). It is. Furthermore, (S, r□) is a temperature detector provided in the cooling water pipe (26), and (Stw4) and (S*wc) are temperature detectors provided in the cooling water pipe (28). It is a flow rate detector.

(B) is a high temperature generator (1) when the heat input becomes larger than the heat output by exceeding the allowable limit during operation of the absorption chiller (A).
This is an overheating prevention device that stops heating. Overheating prevention device (B
) are the detectors (S□W+), (S□w2>, (St
Lol! A first human heat measuring device (100) receives signals from the fuel flow detector (SFF) and calculates the amount of heat of the chilled water using these detected values to measure the heat absorption amount Q8 of the evaporator (4), and a signal from the fuel flow rate detector (SFF). High temperature generator (1) by calculating the heat source heat amount while receiving
The amount of heat input Q. a second person heat measuring device (101) that measures the temperature of the body, and a heat input calculator (102) that calculates the total heat input amount (Qm-t-qa) of the absorption refrigerator (A) while receiving signals from these measuring devices. and the detector (ST□), (STW4)
, (S□C), calculate the cooling water heat amount based on these detected values, and calculate the heat release amount QA of the absorber (5) and the heat release amount Qc of the condenser (3), that is, the heat release amount Qc of the absorption refrigerator (A). A heat output measuring device (103) measures the amount of heat output (QA+Q,), and while receiving signals from this heat output measuring device and a heat input calculator (102), heat output, that is, the amount of heat output (QA+QC:
l and heat input, that is, amount of heat input [QI! 10 Q0] and a determiner (104) that compares and determines whether the heat input is larger than the heat output beyond the allowable range.
) and a controller (106) that issues a warning in response to a discrimination signal from the high temperature generator (1). Please note that the above allowable range is for absorption chillers (
It is selected based on the ratio of the amount of heat radiated from the component wall of the component equipment to the outside air, ie, the amount of natural heat radiated QN, to the heat input (QII 100 G). This ratio varies depending on conditions such as the type of wall material and outside temperature, but it is usually around 10%. For this reason, a tolerance range is usually selected such that heating of the high temperature generator (1) is stopped when the heat input [QE+00] becomes greater than 1.1 times the heat output (QA+QC:).

The superheated fat stopper device (B> is, as shown in Figure 2,
It is configured as a computer system in which the above components are connected by a BUS for these access signals, and the ROM
%RAM, MPU [microprocessor unit],
It is made up of computer parts such as I/F [interface]. In addition, FIG. 2 is a block diagram showing an example of a computer system of the overheating assistant device (B). In FIG. 2, for example, the RAM for the first person's temperature measuring device (100) includes a detector (Stw+).
, (S, rwz) , (The chilled water inlet/outlet temperature and chilled water flow rate are inputted and recorded as measurement data every second [for example, every second] by the SFWI signal, and the M
The instantaneous cold water inlet/outlet temperature difference and cold water heat amount (endothermic amount Q,) calculated by the PU are recorded as measurement data. Similarly, the RAM for the thermal output measuring device (103) includes:
Detector (S?ws), (StW4), (Srwc
) signals, the cooling water inlet/outlet temperature and cooling water flow rate are input and recorded as measurement data, and the momentary cooling water inlet/outlet temperature difference and cooling water heat amount, that is, heat output amount [QA+Qc], which are calculated by the MPU, are measured. Recorded as data. In addition, a second person fever measuring device (
101), the calorific value per unit flow rate of the fuel used is input by keyboard operation and stored as reference data, and the fuel flow rate is input as measurement data by the signal from the flow rate detector (Syr). At the same time, the amount of heat input Qc calculated by the MPU process of multiplying the calorific value per unit flow rate of fuel, which is reference data, and the flow rate of fuel, which is measured data, is recorded as measured data. The heat absorption amount Q and the heat input amount Q are stored in the RAM for the heat input calculator (102). MP that adjusts
Total heat input i [q*+qa] calculated by processing U
is recorded as measurement data. It should be noted that these measurement data can be appropriately printed out or displayed, for example, via a printout section or a display section of the alarm (105) by operating the keyboard. Furthermore, the amount of heat input (Q
*+Qa) is greater than 1.1 times the heat output (QA+QC), and the MPU performs arithmetic processing to determine whether the heat input [heat input] is 1.1 times the heat output [thermal output]. The controller (106) is activated by the signal from the MPU when the temperature exceeds the limit, and the heating of the high temperature generator (1) is stopped, and the alarm (106) is activated.
05) issues an alarm by, for example, ringing a warning bell. That is, the MPU also functions as a determiner (104). In addition, the heat input [QR+QG
] is larger than 1.1 times the amount of heat output (QA + QC), and arithmetic processing such as multiplication and addition processing is performed by the MPU.
Needless to say, a program is written to execute the program. Furthermore, although not shown in FIG. 2, it goes without saying that the device (B) is equipped with, for example, a clock circuit incorporating a crystal oscillator.

In this way, the device (B) detects the momentary heat balance during operation of the absorption chiller (A), and allows the heat input to exceed the heat output within a preset allowable range [heat input amount QI! + Q a exceeds the range of 1.1 times or less of the heat output Q A + Q c, the heating of the high temperature generator (1) is immediately stopped. Therefore, heat does not accumulate within the absorption refrigerator (A), and overheating thereof can be reliably prevented. In addition, compared to conventional systems that stop heating the high-temperature generator (1) after a considerable amount of time has passed since the heat balance of the absorption chiller (A) is disrupted and excessive heat input occurs, fuel is wasted. consumption is reduced, and deterioration of the components of the high temperature generator (1) due to overheating is also reduced.

In addition, if the absorption chiller (A) has complete insulation between the outer wall and the outside air and natural heat radiation is extremely small, the judgment device when the amount of heat input (QII + QG) becomes larger than the amount of heat output [QA + QC] (104) makes the controller (1
06) may be used. In other words, there is no need to set a tolerance range. Furthermore, it goes without saying that the allowable range may be set as appropriate depending on the degree of insulation.

It goes without saying that the heating of the high temperature generator (1) can be stopped by fully closing the fuel flow control valve (vr) and/or by stopping the operation of the burner (not shown).

(G) Effects of the Invention As described above, the present invention provides a function to directly detect when the heat balance of the absorption chiller is disrupted and excessive heat input occurs, and to immediately stop the heating of the generator. This provides the absorption chiller with the effect of preventing wasteful consumption of the drive heat source of the absorption chiller during excessive heat input, as well as preventing overheating of the generator and accompanying deterioration of the generator components. , is of high practical value as it can accurately prevent overheating of absorption refrigerators.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration explanatory diagram showing one embodiment of the overheat prevention device for an absorption refrigerator according to the present invention, and FIG. 2 is a block diagram showing an example of the overheat prevention device as a computer system. (A)...Absorption refrigerator, (1)...High temperature generator,
(3)... Condenser, (4)... Evaporator, <5
)...Absorber, (STw+>, (Stwt), (S
tw-s), (Stwa)...temperature detector, (S.wc), (SpWt), (Spy)-flow rate detector,
(B)... Overheating prevention device, <100)... First person's temperature measuring device, (101)... Second person's temperature measuring device, (1
02)...Heat input calculator, (103)...Heat output measuring device, (104)...Judgment device, (106)...
・Controller, (”/F)...Flow rate control valve. Applicant: Sanyo Electric Co., Ltd. and one other agent Patent attorney Takuji Nishino and one other person No. 20

Claims (1)

[Claims] (1) A heat output measuring device that measures the heat radiation amount of the absorption chiller by measuring the cooling water inlet/outlet temperature and cooling water flow rate of the absorber and/or condenser and calculating the amount of heat of the cooling water, and the chilled water inlet/outlet of the evaporator. There is a heat input measuring device that measures the heat absorption amount of the evaporator by calculating the amount of heat absorbed by the evaporator while measuring the temperature and flow rate of the cold water, and a heat input measuring device that measures the heat source heat amount by measuring the temperature and flow rate of the heat source fluid in the generator and the flow rate of the fuel. A heat input measuring device calculates and measures the heat input of the generator, and while receiving signals from these heat input measuring devices, the total heat input of the absorption chiller is calculated by adding the heat absorbed by the evaporator to the heat input of the generator. A heat input calculator that calculates the heat input, a determiner that compares and determines the magnitude of the heat input and heat output of the absorption refrigerator while receiving signals from this calculator and the heat output measuring device, and a determiner that compares and determines the magnitude of the heat input and heat output of the absorption refrigerator. and a controller that stops heating the generator in response to a determination signal from a determiner when the temperature increases or exceeds a preset allowable range. Device.