JPH1163742A - Device for detecting and controlling degree of vacuum in drum of absorptive freezer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent occurrence of rust in a drum and prevent the deterioration of performance, by taking a measure to prevent the discharge and leakage of air promptly, in case that it can be judged that there was air leakage, by enabling the detection of the existence of the air leakage into the drum even in operation stoppage. SOLUTION: Outside air temperature is detected with a means (outside air temperature sensor) 14 for detecting the outside air, and the saturation steam pressure of the drum 1 of an absorptive freezer is obtained from the saturation steam pressure in this outside air temperature, and further the pressure in the drum is detected with a means (in-drum pressure sensor) 15 for detecting the pressure in the drum, and it is compared with the saturation steam pressure. Then, in case that the in-drum pressure is over the saturation steam pressure, a liquid absorptive pump 8 is automatically operated to dive out the air leaked in the drum into an air bleed chamber 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-body vacuum degree detection control device for detecting and controlling the degree of vacuum in a body of an absorption refrigerator used in an absorption chiller / heater or the like.

[0002]

2. Description of the Related Art FIG. 3 is a schematic diagram showing the construction of an absorption refrigerator used in a conventional absorption chiller / heater. An evaporator 2 and an absorber 2 are provided inside a body 1 which is a main part of the absorption refrigerator. Vessel 3 is provided. Non-condensable gas pipes 4 from the lower part of the absorber 3
Is connected to a bleed chamber 6 beside the air tank 5. The air tank 5 is provided with a pressure sensor 7 for detecting the internal pressure.

[0003] An absorbent pump 8 is connected to a pipe provided at the bottom of the body 1 so as to guide the absorbent to the bleed chamber 6 via an absorbent supply pipe 9. The non-condensable gas and the absorbing liquid which are respectively guided to the bleeding chamber 6 via the non-condensable gas pipe 4 and the absorbing liquid supply pipe 9 are guided to the gas-liquid separator 11 via the bleeding pipe 10. Of the absorbing liquid and the non-condensable gas mixed in the bleed pipe 10, only the non-condensing gas is transferred to the air tank 5 via the gas riser pipe 12, and the absorbing liquid is transferred to the cylinder via the absorbing liquid return pipe 13. Returned to Part 1.

Next, a procedure for detecting the degree of vacuum in the apparatus having the above configuration will be described. During operation of the absorption refrigerator, the refrigerant vapor generated in the evaporator 2 is absorbed by the absorber 3, and the non-condensable gas is collected in the absorber 3 by the flow. The absorbing liquid discharged from the absorbing liquid pump 8 passes through the absorbing liquid supply pipe 9 and the bleeding pipe 10 in the bleeding chamber 6.
Flow into At this time, the non-condensable gas collected around the absorber 3 is guided to the bleed pipe 10 through the non-condensable gas pipe 4 by the ejector effect of the absorbing liquid in the bleed chamber 6. Thereafter, the non-condensable gas is led to the air tank 5 via the gas-liquid separator 11 and the gas riser 12. By detecting the pressure inside the air tank 5 to which the non-condensable gas has been guided as described above with the pressure sensor 7, the degree of vacuum in the apparatus can be detected.

[0005] As described above, in the conventional absorption refrigerator,
The generated hydrogen (H2) and mixed air can be stored in the air tank 5 using the ejector effect.
As long as the operation is continued, the inside of the body 1 is always exhausted, and there is no problem such as generation of rust.

[0006]

However, if air leaks into the absorption chiller, rust is generated in the body, which significantly degrades the performance of the absorption chiller. Therefore, it is necessary to constantly control the degree of vacuum inside the body, to detect air leakage, and to immediately detect the air leakage, and to immediately take measures to prevent air leakage and air leakage.

[0007] Based on such a need, in the conventional absorption refrigerator, the pressure sensor 7 provided in the air tank 5 detects a rise in pressure, so that the air tank 5 is cooled.
It detected the rise in the degree of vacuum inside and detected the presence or absence of air leakage into the body. However, in order to detect the degree of vacuum, it is necessary to operate the absorbing liquid pump 8 and convey the non-condensable gas from the inside of the body to the bleeding chamber 6. Therefore, the non-condensable gas in the body part 1 cannot be guided to the air tank 5 unless the absorption refrigerator is in operation, and if air leaks into the body of the absorption refrigerator unit while the operation is stopped. , Vacuum leak,
That is, even if the degree of vacuum is reduced due to air leakage, air leakage cannot be detected until the next operation is started. As a result, a state in which air leaks into the body lasts for a long period of time, causing rust to progress in the body, and there is a problem that the performance of the refrigerator is significantly deteriorated.

On the other hand, the temperature of the absorbing liquid and the temperature of the refrigerant when the apparatus is stopped depend on the outside air temperature. Further, since the degree of vacuum in the body changes according to the saturated vapor pressure determined by the temperature of the absorbent and the temperature of the refrigerant, it has been extremely difficult to judge the presence or absence of a vacuum leak by simply detecting the pressure in the body.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and detects the presence or absence of air leakage even during operation stoppage, and immediately takes measures to prevent air discharge and leakage. It is another object of the present invention to provide a control apparatus for detecting the degree of vacuum in a body of an absorption refrigerator, which can prevent rust in the body and prevent performance deterioration.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention comprises a temperature detecting means for detecting the outside air temperature around the body of an absorption refrigerator, Pressure detecting means for detecting the inside pressure of the body, a calculating unit for calculating the saturated vapor pressure in the body during the stop of the absorption refrigerator based on the detected outside air temperature, and the inside of the body during the stop of the absorption refrigerator. The pressure and the calculated saturated vapor pressure are compared, and a comparison determination unit that determines whether the in-body pressure is equal to or more than a predetermined amount from the saturated vapor pressure, and when it is determined that the in-body pressure has increased by a predetermined amount or more. And a control unit for discharging non-condensable gas in the body.

According to this configuration, the condition in the body is constantly monitored, and pressure fluctuations can always be accurately recognized. If air leaks, the air can be quickly discharged. .

In order to achieve the above object, the present invention is characterized in that in the above-mentioned apparatus, when the pressure in the cylinder is higher than the saturated vapor pressure by 2 mmHg or more, the non-condensable gas in the cylinder is discharged. And

According to this configuration, it is possible to quickly discharge the leaked air.

In order to achieve the above-mentioned object, the configuration of the present invention is characterized in that it comprises an alarm means for issuing an alarm when an increase in pressure in the body is detected.

Here, the alarm means is an alarm by voice or display, and may also be used to specify a location where an abnormality has occurred.

According to this configuration, it is possible to quickly take measures against air leakage of the absorption refrigerator.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an absorption refrigerator equipped with an in-body vacuum degree detection control device according to an embodiment (hereinafter, referred to as an embodiment) of the present invention. An evaporator 2 and an absorber 3 are provided inside a body 1 which is a main part of the machine. An uncondensable gas pipe 4 extends from the lower part of the absorber 3 and a bleed chamber 6 next to the air tank 5.
It is connected to the. The air tank 5 is provided with a pressure sensor 7 for detecting the internal pressure.

An absorbent pump 8 is connected to a pipe extending downward from the bottom of the body 1 so as to guide the absorbent to the bleed chamber 6 via an absorbent supply pipe 9. The non-condensable gas such as air or hydrogen and the absorbing liquid, which are respectively guided to the bleeding chamber 6 via the non-condensable gas pipe 4 and the absorbing liquid supply pipe 9, are guided to the gas-liquid separator 11 via the bleeding pipe 10. Of the absorbing liquid and the non-condensable gas mixed in the bleed pipe 10, the non-condensing gas is transferred to the air tank 5 via the gas riser pipe 12, and the absorbing liquid is transferred to the body via the absorbing liquid return pipe 13. It is to be returned to 1. As described above, the main configuration of the absorption refrigerator is the same as the conventional one shown in FIG.

A characteristic feature of the present embodiment is that an outside air temperature sensor 14 for detecting an outside air temperature is provided around the body 1, and an inside pressure sensor 15 for detecting an inside pressure in the body 1 is provided.
Is provided, and a control unit 16 is provided which performs a predetermined calculation using the outputs of the outside air temperature sensor 14 and the body pressure sensor 15 as inputs, and controls the operation of the absorbent pump 8 based on the calculation result. By the way. Note that, in the present embodiment, the case where the control unit 16 includes a comparison determination unit based on a calculation result is shown, but a comparison determination unit may be separately provided.

Next, the operation of the control device 16 will be described with reference to FIG.

First, the outside air temperature T around the body is obtained from the outside air temperature sensor 14. Further, the in-body pressure P of the absorption refrigerator is acquired by the in-body pressure sensor 15, which is a means for detecting the in-body pressure (S100). By the way, when the operation of the absorption refrigerator is stopped for a long time, the absorption liquid temperature and the refrigerant temperature of the absorption refrigerator become equal to the outside air temperature. Therefore, by measuring the outside air temperature T, it can be regarded as the body temperature. Also, during operation stop, the refrigerant vapor and the non-condensable gas are
Are uniformly distributed within.

Next, the controller 16 calculates a saturated vapor pressure Pw based on the outside air temperature T (S101). At this time, the pressure in the body of the absorption refrigerator in which the non-condensable gas does not leak during the stop of the absorption refrigerator is generally substantially equal to the saturated vapor pressure of water. Therefore, the outside air temperature sensor 1 which is a means for detecting the outside air temperature
4 reads the outside air temperature T detected by the control unit 16 into the control unit 16,
The saturated vapor pressure of water at this temperature can be obtained by the conversion operation of the control unit 16.

Subsequently, the comparison / determination section in the control section 16 adds 2 mmHg to the conversion result of the in-body pressure P and the saturated vapor pressure Pw.
(S102).

If P ≧ Pw + 2, it is determined that air has leaked into the body 1, and the absorbent pump 8 is operated (S
103), the air leaking into the body 1 is expelled into the air tank 5 through the bleed chamber 6. As a result, it is possible to prevent the occurrence of rust in the body 1 and to prevent performance degradation of the absorption refrigerator. In the present embodiment, a change of 2 mmHg or less from the past data is regarded as an error range, and (S
Although the judgment of 102) was made, the criterion may be appropriately changed within a range where rust does not occur.

When the absorbing liquid pump 8 is automatically operated by the above-described processing, the control section 16 sends an abnormality signal to the abnormality alarm device 17 to issue an alarm (S104).
In this case, the alarm is an alarm visually displayed on a monitor such as a rotating light, or an alarm by a siren or a sound announcement. In addition, if the leak position of air or the like can be specified, the leak position may be displayed via a monitor or the like. As described above, when it is determined that air leakage has occurred in the body 1, by providing a means for immediately issuing an abnormality report,
It is possible to quickly take measures to prevent leakage of non-condensable gas such as air into the body 1.

In the case of NO in (S102), (S1
00), and the following operation is executed again.

[0027]

According to the present invention, even when air leaks into the body while the absorption type refrigerator is stopped, the rise in the body pressure due to the air leak is taken into consideration in consideration of the influence of the outside air temperature. By accurately detecting and automatically operating the absorbing liquid pump as needed, air can be discharged from the inside of the body to the bleeding chamber, thereby preventing rust inside the body.

Further, when it is determined that air has leaked into the body, an abnormal signal is issued by the abnormal alarm device so that measures to prevent air leakage can be taken immediately.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an absorption refrigerator equipped with an in-body vacuum degree detection control device showing a preferred embodiment of the present invention.

FIG. 2 is a flowchart showing an operation of the in-body vacuum degree detection control device shown in FIG. 1;

FIG. 3 is a schematic configuration diagram of a conventional absorption refrigerator.

[Explanation of symbols]

1 body, 5 air tank, 6 bleeding chamber, 7 pressure sensor, 8 absorbent pump, 14 outside air temperature sensor, 15
In-body pressure sensor, 16 control device, 17 abnormality alarm device

Claims (3)

[Claims] A temperature detecting means for detecting an outside air temperature around a body of the absorption refrigerator; a pressure detecting means for detecting a pressure inside the body of the body; and an absorption system based on the detected outside air temperature. A calculating unit for calculating the saturated vapor pressure in the cylinder when the refrigerator is stopped, and comparing the calculated internal vapor pressure with the calculated internal vapor pressure when the absorption refrigerator is stopped, and the internal pressure is calculated from the saturated vapor pressure. A comparison determination unit that determines whether the pressure is equal to or more than a predetermined amount; and
A control unit for discharging non-condensable gas in the body, and a control device for detecting the degree of vacuum in the body of the absorption refrigerator, comprising: 2. The apparatus according to claim 1, wherein when the pressure in the body is higher than the saturated vapor pressure by 2 mmHg or more, the non-condensable gas in the body is discharged. . 3. An in-body vacuum degree detection control of an absorption refrigerator as set forth in claim 1, further comprising an alarming means for issuing an alarm when an increase in the inside pressure of the body is detected. apparatus.