Refrigerant Recovery Equipment

Abstract

To provide a refrigerant recovery device which can suppress increase in the cost, and can reduce attention of an operator to a temperature during refrigerant recovery.SOLUTION: A refrigerant recovery device 1 for recovering a refrigerant of air-conditioning equipment by sucking and compressing the refrigerant and sending the refrigerant to a recovery cylinder includes: an operation unit 15 for receiving selection of the refrigerant to be recovered from two or more refrigerants; a pressure measurement unit 12 for measuring a pressure of the refrigerant sent to the recovery cylinder; a determination unit 161 for determining whether the measured pressure exceeds a threshold value associated with the selected refrigerant or not; and a warning unit 162 for issuing a warning when the measured pressure exceeds the threshold value.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a refrigerant recovery device. [Background technology]

[0002] Air conditioners and other air conditioners, refrigeration and freezing equipment, and the like use a refrigerant to lower the temperature inside a room. When removing such air conditioners and the like, the refrigerant is collected in a collection cylinder. In the process of collecting the refrigerant, the refrigerant is compressed and then collected in the collection cylinder (see, for example, Patent Document 1). In the process of compressing the refrigerant, the temperature and pressure of the refrigerant increase due to the heat of condensation. This increase in temperature and pressure is one of the factors that reduces the efficiency of the collection operation. For example, as the refrigerant is compressed and sealed in the collection cylinder, the temperature of the refrigerant increases, causing internal expansion, which may damage the collection cylinder.

[0003] Therefore, the recovery cylinder is equipped with a safety valve called a fusible plug. The fusible plug has the property of melting at a certain temperature, and melts when the inside of the recovery cylinder becomes hot, releasing the gas inside. This prevents the danger of the refrigerant in the recovery cylinder becoming hot and high pressure.

[0004] However, if a fusible plug melts, the gas inside is released, causing the recovery process to be interrupted. Therefore, Patent Document 2 discloses a device that can prevent the melting of a fusible plug without damaging the recovery container. The device described in Patent Document 2 receives temperature information about the fusible plug from a temperature sensor attached to the fusible plug, and outputs warning information if it receives temperature information that is lower than the melting temperature and equal to or higher than a preset reference temperature. In this way, the melting of the fusible plug is prevented. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2005-344988 A [Patent Document 2] JP 2014-145536 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, since devices that recover refrigerant generally handle high-pressure gas, they have a sensor that measures pressure but no sensor that measures temperature. For this reason, the device described in Patent Document 2 needs to be provided with a separate temperature sensor that directly measures the temperature of the fusible plug, which can lead to problems with increased costs for the device.

[0007] Therefore, one example of an object of the present invention is to provide a refrigerant recovery device that can suppress an increase in costs and reduce the need for workers to pay attention to temperature when recovering a refrigerant. [Means for solving the problem]

[0008] In order to achieve the above object, a refrigerant recovery device according to one aspect of the present invention comprises: A refrigerant recovery device that draws in and compresses a refrigerant from an air conditioner, sends the refrigerant to a recovery cylinder, and recovers the refrigerant, An operation unit that accepts a selection of a refrigerant to be recovered from two or more refrigerants; A pressure measuring unit for measuring the pressure of the refrigerant sent to the recovery cylinder; a determination unit that determines whether the measured pressure exceeds a threshold value associated with the selected refrigerant; a warning unit that issues a warning when the measured pressure exceeds the threshold value; Equipped with. Effect of the Invention

[0009] According to the present invention, it is possible to suppress an increase in costs and reduce the need for workers to pay attention to temperature when recovering a refrigerant. [Brief description of the drawings]

[0010] [Figure 1]FIG. 1 is a diagram illustrating a configuration for explaining refrigerant recovery using a refrigerant recovery device. [Diagram 2] FIG. 2 is a block diagram showing the configuration of the refrigerant recovery device. [Diagram 3] FIG. 3 is a diagram illustrating an example of the display unit. [Figure 4] FIG. 4 is a flow diagram showing the operation of the refrigerant recovery device. [Diagram 5] FIG. 5 is a flow diagram showing the operation of the refrigerant recovery device when the threshold value is set. [Figure 6] FIG. 6 is a block diagram showing the configuration of a modified refrigerant recovery device. [Figure 7] FIG. 7 is a flow chart showing the operation of the refrigerant recovery device of the modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A refrigerant recovery device according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a diagram showing a configuration for explaining refrigerant recovery using a refrigerant recovery device 1. The refrigerant recovery device 1 is connected to an air conditioner 2 and a recovery cylinder 3.

[0012] The air conditioner 2 is a device that uses a refrigerant to cool or heat the interior space of a building, a vehicle, a ship, an airplane, or the like.

[0013] The recovery cylinder 3 stores the refrigerant sucked from the air conditioner 2 by the refrigerant recovery device 1. Although not shown, the recovery cylinder 3 has a fusible plug. When the pressure inside the container becomes high and reaches a certain temperature, the fusible plug melts and releases the gas inside the recovery cylinder 3.

[0014] The refrigerant recovery device 1 is a device for recovering refrigerant from air conditioners 2. Note that the refrigerant recovery device 1 may also be a device for recovering refrigerant from refrigeration and freezing equipment. The refrigerant recovery device 1 has a suction port 1A and a discharge port 1B. The suction port 1A is connected to the air conditioners 2 via a hose 4A. The discharge port 1B is connected to the recovery cylinder 3 via a hose 4B. The refrigerant recovery device 1 compresses the refrigerant sucked from the air conditioners 2 via the hose 4A, and sends it to the recovery cylinder 3 via the hose 4B. That is, the compressed refrigerant is stored in the recovery cylinder 3.

[0015] The refrigerant becomes hot by being compressed by the refrigerant recovery device 1. Therefore, if the temperature of the refrigerant sent from the refrigerant recovery device 1 to the recovery cylinder 3 is high, the fusible plug of the recovery cylinder 3 may melt and the internal gas may be released. Therefore, the refrigerant recovery device 1 measures the pressure of the refrigerant discharged from the refrigerant recovery device 1, and issues a warning sound if the measured pressure is equal to or higher than a threshold value. By issuing a warning sound, the worker performing the refrigerant recovery is prompted to stop the recovery work, cool the recovery cylinder 3, or adjust the opening of the valve that opens and closes during recovery.

[0016] Furthermore, the temperature change of the refrigerant differs depending on the type of refrigerant. Specifically, some refrigerants reach high temperatures at low pressure, while others reach high temperatures at high pressure. Therefore, the refrigerant recovery device 1 changes the threshold value used to determine the measured pressure depending on the type of refrigerant. This makes it possible to avoid a decrease in recovery work efficiency compared to when the same threshold value is always used regardless of the type of refrigerant.

[0017] For example, when the threshold is set to a high pressure, if an attempt is made to collect a refrigerant that is heated at a low pressure, no warning sound will be emitted even though the temperature is heating up. In this case, the fusible plug will melt, releasing the gas in the collection cylinder 3, and the collection operation will be interrupted. Also, when the threshold is set to a low pressure, if an attempt is made to collect a refrigerant that is heated at a high pressure, a warning sound will be emitted even though the temperature is not heating up. In this case, the collection operation will also be interrupted. For this reason, by appropriately changing the threshold depending on the type of refrigerant, a decrease in the efficiency of the collection operation can be avoided.

[0018] The following provides a detailed explanation of the refrigerant recovery apparatus 1. FIG.

[0019] The refrigerant recovery device 1 includes a recovery pump 11, a pressure measuring unit 12, a display unit 13, a speaker 14, an operation unit 15, and a control unit 16.

[0020] The recovery pump 11 is a pump for transporting the refrigerant from the air conditioner 2 to the recovery cylinder 3. The recovery pump 11 is driven by, for example, an electric motor. The recovery pump 11 sucks the gaseous refrigerant from the air conditioner 2 through the hose 4A, compresses the sucked refrigerant, and sends it to the recovery cylinder 3 through the hose 4B.

[0021] The pressure measuring unit 12 includes a sensor that measures the pressure of the refrigerant sucked by the recovery pump 11, and a sensor that measures the pressure of the refrigerant discharged by the recovery pump 11 and sent to the recovery cylinder 3 (hereinafter referred to as discharge pressure). Note that the pressure measuring unit 12 is capable of measuring both fluorocarbon refrigerants and non-fluorocarbon refrigerants.

[0022] FIG. 3 is a diagram showing an example of display unit 13. Display unit 13, which is a display, displays, for example, the pressure measured by pressure measuring unit 12. Display unit 13 represents the measured pressure as a numerical value and a bar. Display unit 13 also displays the selected refrigerant to be recovered. The operation of selecting the refrigerant is accepted by operation unit 15, which will be described later. Note that display unit 13 may also display the operating status of refrigerant recovery device 1 (for example, stopped, operating, etc.). Also, the display mode of display unit 13 is an example and can be changed as appropriate.

[0023] The speaker 14 outputs a buzzer as a warning sound.

[0024] The operation unit 15 is, for example, a button or a dial that accepts operations of the refrigerant recovery device 1. The operation unit 15 accepts the selection of a refrigerant to be recovered from two or more refrigerants. In this embodiment, the refrigerant recovery device 1 is capable of selecting between "refrigerant A" and "refrigerant B". Examples of "refrigerant A" and "refrigerant B" include R22 refrigerant and R134a refrigerant. The refrigerant recovery device 1 may be capable of selecting between three or more types of refrigerant. The operation unit 15 also accepts, for example, operations to start and stop the recovery pump 11, to open and close the suction port 1A and the discharge port 1B, to open and close the valves of the recovery pump 11, and the like.

[0025] The control unit 16 performs various controls of the refrigerant recovery device 1, such as drive control of the recovery pump 11, display control of the display unit 13, and output control of a warning sound from the speaker 14. The control unit 16 includes, for example, a CPU, a RAM, and a ROM, and has various functions by executing a predetermined program stored in the ROM. Note that the various functions of the control unit 16 may be realized by software, hardware, or a combination of both.

[0026] The control unit 16 has the functions of a determination unit 161 and a warning unit 162 .

[0027] The determination unit 161 compares the threshold value associated with the refrigerant selected by the operation unit 15 with the discharge pressure measured by the pressure measurement unit 12. Then, the determination unit 161 determines whether the measured discharge pressure exceeds the threshold value. The threshold value is, for example, associated with the refrigerant in advance and stored in a memory (ROM). The determination unit 161 obtains the threshold value associated with the selected refrigerant from the memory.

[0028] In this embodiment, the threshold value "P TA (<3MPa)" is associated with "Refrigerant B", and the threshold "P TB In this case, when "refrigerant A" is selected, the determination unit 161 determines whether the threshold value P TA The pressure measuring unit 12 compares the discharge pressure measured by the pressure measuring unit 12 with the threshold value P TB is compared with the discharge pressure measured by the pressure measuring unit 12.

[0029] The refrigerant recovery device 1 may be capable of selecting three or more types of refrigerant, and a threshold value may be associated with each refrigerant.

[0030] The warning unit 162 issues a warning when the measured discharge pressure exceeds a threshold value as a result of the judgment by the judgment unit 161. For example, the warning unit 162 outputs a buzzer from the speaker 14. Note that the warning unit 162 may issue a warning by flashing characters or marks on the display unit 13, or the like.

[0031] In this embodiment, regardless of the type of refrigerant, the determination unit 161 compares the discharge pressure measured by the pressure measurement unit 12 with a threshold value of "3 MPa." If the comparison result indicates that the measured discharge pressure exceeds 3 MPa, the warning unit 162 outputs a buzzer from the speaker 14, and the control unit 16 forcibly stops driving the recovery pump 11. The threshold value "3 MPa" used at this time is just an example, and may be 3 MPa or more.

[0032] The following describes the operation of the refrigerant recovery device 1. Fig. 4 is a flow diagram showing the operation of the refrigerant recovery device 1. Note that the operation described below is an example, and the operation of the refrigerant recovery device 1 is not limited to Fig. 4.

[0033] The control unit 16 receives a selection of a refrigerant from the operation unit 15 (S1). At this time, the control unit 16 displays the selected refrigerant on the display unit 13. Next, when an operation to start driving the recovery pump 11 is input from the operation unit 15, the control unit 16 drives the recovery pump 11 to start recovering the refrigerant (S2).

[0034] The control unit 16 measures the discharge pressure by the pressure measuring unit 12 (S3). The control unit 16 judges whether the refrigerant selected in S1 is "Refrigerant A" (S4). If the selected refrigerant is "Refrigerant A" (S4: YES), the judgment unit 161 of the control unit 16 judges whether the refrigerant is a threshold value P TA The measured discharge pressure is calculated based on the threshold value P TA It is determined whether the measured discharge pressure is equal to or greater than the threshold value P TA If so (S5: YES), the warning unit 162 of the control unit 16 outputs a buzzer from the speaker 14 for a predetermined time to warn the user (S7).

[0035] The measured discharge pressure is the threshold P TA If it is not the same (S5: NO), or after issuing the warning in S7, the control unit 16 judges whether the operator has pressed the stop button to stop operation (S8). If operation is to be stopped (S8: YES), the control unit 16 stops the recovery pump 11 (S11). If operation is not to be stopped (S8: NO), the process of S9 is executed.

[0036] In S4, if the refrigerant selected is not "Refrigerant A" (S4: NO), that is, if the refrigerant selected in S1 is "Refrigerant B", the determination unit 161 of the control unit 16 determines the threshold value P TB The measured discharge pressure is calculated based on the threshold value P TB It is determined whether the measured discharge pressure is equal to or greater than the threshold value P TBIf so (S6: YES), the warning unit 162 of the control unit 16 outputs a buzzer from the speaker 14 for a predetermined time to warn the user (S7).

[0037] The measured discharge pressure is the threshold P TB If it is not the above (S6: NO), or after issuing the warning in S7, the control unit 16 judges whether the operator has pressed the stop button to stop operation (S8). If operation is to be stopped (S8: YES), the control unit 16 stops the recovery pump 11 (S11). If operation is not to be stopped (S8: NO), the process of S9 is executed.

[0038] The determination unit 161 of the control unit 16 determines whether the measured discharge pressure is 3 MPa or more (S9). If the measured discharge pressure is 3 MPa or more (S9: YES), the warning unit 162 of the control unit 16 outputs a buzzer from the speaker 14 to warn (S10). Then, the control unit 16 stops the recovery pump 11 (S11). That is, the refrigerant recovery device 1 is forcibly stopped when the discharge pressure becomes 3 MPa or more, regardless of the type of refrigerant. If the measured discharge pressure is not 3 MPa or more (S9: NO), the process from S3 is executed.

[0039] As described above, according to the refrigerant recovery device 1 of the present embodiment, when the measured discharge pressure of the refrigerant is equal to or higher than the threshold value corresponding to that refrigerant, a warning sound is generated to prompt the worker recovering the refrigerant to take action such as stopping the recovery work. This reduces the need for the worker to pay attention to the temperature during refrigerant recovery. In addition, since the refrigerant recovery device 1 estimates the temperature of the recovery cylinder 3 from the discharge pressure, it is not necessary to provide a separate sensor for measuring the temperature, and therefore costs can be suppressed.

[0040] (Variation 1) In the present embodiment, the threshold value is described as being associated with the refrigerant in advance and stored in a memory or the like. However, the threshold value may be input by an operator. The input operation of the threshold value is accepted by the operation unit 15, for example.

[0041] FIG. 5 is a flow diagram showing the operation of the refrigerant recovery device 1 when the threshold value is set.

[0042] When the control unit 16 is in a threshold setting mode (S21), it accepts the selection of a refrigerant (S22). Then, when the control unit 16 accepts an input of a threshold corresponding to the selected refrigerant (S23), it associates the threshold with the refrigerant accepted in S22 and stores the threshold in a memory (e.g., RAM) (S24).

[0043] By allowing the threshold value to be input in this manner, the refrigerant recovery device 1 can be applied to the recovery of a wide variety of refrigerants.

[0044] (Variation 2) In this embodiment, when the measured discharge pressure exceeds the threshold value, only a warning is issued, but it is also possible to forcibly stop recovery pump 11 and stop refrigerant recovery. FIG. 6 is a block diagram showing the configuration of refrigerant recovery device 1 of the modified example. Control unit 16 of refrigerant recovery device 1 of the modified example further includes a stop unit 163. When determination unit 161 determines that the measured discharge pressure exceeds the threshold value, stop unit 163 stops recovery pump 11 and stops recovery of refrigerant.

[0045] Fig. 7 is a flow diagram showing the operation of the refrigerant recovery device 1 of the modified example. The processes from S21 to S27 are similar to the processes from S1 to S7 in Fig. 4, and therefore a description thereof will be omitted. After issuing a warning in S27, the control unit 16 stops the recovery pump 11 (S30). This allows the refrigerant recovery device 1 to forcibly stop the refrigerant recovery operation.

[0046] The processing from S28 to S30 is similar to the processing from S9 to S11 in FIG. 4, and therefore a description thereof will be omitted.

[0047] In this way, when the discharge pressure exceeds the threshold value, the recovery pump 11 can be stopped without the operator's operation, and the refrigerant recovery operation can be forcibly stopped. As a result, the operator's attention to the temperature during refrigerant recovery can be further reduced. [Explanation of symbols]

[0048] 1 Refrigerant recovery equipment 1A suction port 1B Discharge port 2 Air conditioning equipment 3. Recovery cylinder 4A, 4B hose 11 Recovery pump 12 Pressure measurement section 13 Display section 14 Speaker 15 Control section 16 Control section 161 Judgment Department 162 Warning section 163 Stop part

Claims

1. A refrigerant recovery device that draws in and compresses a refrigerant from an air conditioner, sends the refrigerant to a recovery cylinder, and recovers the refrigerant, An operation unit that accepts a selection of a refrigerant to be recovered from two or more refrigerants; A pressure measuring unit that measures a suction pressure of the refrigerant drawn from the air conditioner and a delivery pressure of the refrigerant delivered to the recovery cylinder; a determination unit that determines whether the discharge pressure exceeds a threshold value associated with the selected refrigerant; a warning unit that issues a warning when the delivery pressure exceeds the threshold value; A display unit that displays the suction pressure, the delivery pressure, the selected refrigerant, and an operating status of the refrigerant recovery device; Equipped with The display unit displays the suction pressure and the delivery pressure using numerical values ​​and bars. Refrigerant recovery equipment.

2. The operation unit receives an input of a selection of the refrigerant and a threshold value corresponding to the selected refrigerant, The determination unit determines whether or not the delivery pressure exceeds a received threshold value.

2. The refrigerant recovery apparatus of claim 1.

3. A stop unit that stops recovery of the refrigerant when the discharge pressure exceeds the threshold value. The refrigerant recovery apparatus according to claim 1 or 2, further comprising:

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