JP7333514B2 - Refrigerant work support device - Google Patents

Description

The present invention relates to a refrigerant work support device.

Refrigerant units such as air conditioners and refrigerators require refrigerant work such as refrigerant recovery, vacuuming, airtightness testing, and refrigerant charging. Patent Literature 1 proposes an apparatus for recovering refrigerant liquid without leaking refrigerant gas into the atmosphere.

JP-A-6-2994

When performing refrigerant work, it is necessary to connect different devices to the refrigerant unit for each task. However, conventionally, it was necessary to reconnect the device to the port for each operation, which was troublesome.

SUMMARY OF THE INVENTION The present invention has been made in view of such a background, and an object of the present invention is to provide a technique that enables refrigerant work to be performed while a plurality of refrigerant work-related devices are connected at the same time.

The main invention of the present invention for solving the above problems is a refrigerant work support device, comprising two first openings provided with two pressure sensors, a vacuum pump, a refrigerant cylinder, a nitrogen cylinder and a refrigerant recovery machine. a manifold having a plurality of second openings to which at least two of are connected; first and second valves provided in the first and second openings, respectively; and a control unit capable of controlling each of the first and second valves so that only one of them is open at the same time.

Other problems disclosed by the present application and solutions thereof will be clarified by the section of the embodiment of the invention and the drawings.

According to the present invention, refrigerant work can be performed while a plurality of refrigerant work related devices are connected at the same time.

1 is a perspective view of a refrigerant work support device 1; FIG. 1 is a front view of a refrigerant work support device 1; FIG. 2 is a rear view of the refrigerant work support device 1; FIG. 2 is a top view of the refrigerant work support device 1. FIG. 2 is a bottom view of the refrigerant work support device 1; FIG. 1 is a side view of a refrigerant work support device 1; FIG. FIG. 2 is a cross-sectional view taken along line AA of the refrigerant work support device 1; 2 is a circuit diagram of the refrigerant work support device 1; FIG. 4A and 4B are diagrams for explaining signals input to and output from a control unit 16; FIG. 3A and 3B are diagrams for explaining the operation of the refrigerant work support device 1; FIG. It is a figure explaining the flow of the process which concerns on an airtightness test. It is a figure explaining the flow of the process which concerns on confirmation of a leak. It is a figure explaining the flow of the process which concerns on evacuation work. It is a figure explaining the flow of the process which concerns on a refrigerant|coolant filling operation|work. It is a figure explaining the flow of the process which concerns on a refrigerant|coolant collection|recovery work. FIG. 10 is a diagram showing a modification of the operation of the refrigerant work support device 1 related to the refrigerant charging work; It is a figure explaining the conventional refrigerant|coolant operation|work.

The contents of the embodiments of the present invention are listed and explained. A refrigerant work support device according to an embodiment of the present invention has the following configuration.

[Item 1]
a manifold having two first openings with two pressure sensors and a plurality of second openings to which at least two of a vacuum pump, a refrigerant cylinder, a nitrogen cylinder and a refrigerant collector are connected;
first and second valves provided in the first and second openings, respectively;
a control unit capable of controlling each of the first and second valves so that only one of the second openings is open at the same time;
A refrigerant work support device comprising:
[Item 2]
The refrigerant work support device according to item 1,
The manifold further has a third opening for discharging the fluid in the manifold to the outside,
each of the third openings is provided with a third valve;
The controller is capable of controlling each of the second and third valves such that only one of the second and third valves is open at the same time;
A refrigerant work support device characterized by:
[Item 3]
The refrigerant work support device according to item 2,
At least the nitrogen cylinder is connected to the second opening,
When the control unit receives an instruction for an airtightness test,
Open each of the first valves and an input valve to which the nitrogen cylinder is connected among the second valves;
measuring a first pressure based on a signal from the pressure sensor;
closing the first valve and the input valve when the measured first pressure reaches a preset specified value;
measuring a second pressure based on the signal from the pressure sensor after a preset time;
Determining whether the airtightness test has passed or failed based on whether the difference between the first and second pressures is equal to or less than a preset threshold;
A refrigerant work support device characterized by:
[Item 4]
The refrigerant work support device according to any one of items 2 to 3,
At least the vacuum pump is connected to the second opening,
When the control unit receives an instruction for evacuation work,
opening each of the first valves and the vacuum valve of the second valve to which the vacuum pump is connected;
If the pressure indicated by the measured value from the pressure sensor does not reach a predetermined threshold value by the time a preset first time elapses, notifying that a leak has occurred;
A third preset time elapses after closing the first valve and the vacuum valve when a second preset time longer than the first time elapses. Notifying that a leak has occurred when the pressure indicated by the measurement value from the pressure sensor falls below a predetermined threshold by
A refrigerant work support device characterized by:
[Item 5]
The refrigerant work support device according to any one of items 2 to 4,
At least the refrigerant cylinder is connected to the second opening,
The control unit is connected to a device that outputs a signal indicating the amount of refrigerant discharged from the refrigerant cylinder,
When the control unit receives a refrigerant charging instruction,
Open each of the first valves and a refrigerant valve to which the refrigerant cylinder is connected among the second valves,
receive the signal from the device;
calculating the filling amount of the refrigerant based on the signal;
Closing the first valve and the refrigerant valve when the calculated charging amount is equal to or greater than a preset threshold;
A refrigerant work support device characterized by:
[Item 6]
A refrigerant work support device according to item 5,
High-pressure side and low-pressure side ports of an air conditioner are connected to the first opening,
The control unit outputs a signal instructing to close the high-pressure side port when the charging amount reaches or exceeds a set value smaller than the threshold value, and the refrigerant cylinder to the low-pressure side port is discharged. controlling the first valve so that the flow rate of the refrigerant is reduced;
A refrigerant work support device characterized by:
[Item 7]
The refrigerant work support device according to item 5 or 6,
The refrigerant collector is also connected to the second opening,
The control unit closes the first valve and the refrigerant valve when the charging amount becomes equal to or greater than the threshold value, and then the refrigerant collector of the second valve is connected. opening a recovery valve to recover the refrigerant remaining in the refrigerant work support device;
A refrigerant work support device characterized by:
[Item 8]
A refrigerant work support device according to any one of items 2 to 6,
At least the refrigerant collector is connected to the second opening,
When the control unit receives a refrigerant recovery operation instruction,
opening each of the first valves and a recovery valve among the second valves to which the refrigerant recovery device is connected;
closing the first valve and the recovery valve in response to instructions;
A refrigerant work support device characterized by:

<Overview>
A refrigerant work support device 1 according to an embodiment of the present invention will be described below. A refrigerant work support device 1 of the present embodiment is a device that supports refrigerant work related to a device that uses a refrigerant, such as an air conditioner or a refrigerator (hereinafter referred to as a refrigerant unit). Refrigerant work includes an airtightness test, vacuum drawing work, refrigerant filling work, refrigerant recovery work, and the like.

The airtightness test is a work to check whether there is any leakage from the piping joint when the refrigerant unit is installed. The vacuuming operation is the operation of removing the air in the pipe for a specified time and performing vacuum drying. A refrigerant filling operation is an operation of filling a refrigerant unit with a refrigerant. The refrigerant collection work is the work of taking out the refrigerant from the refrigerant unit.

These refrigerant recovery operations have conventionally been performed by reconnecting the refrigerant recovery device 25 to the manifold. FIG. 17 is a diagram for explaining a conventional refrigerant work. As shown in the figure, a port 92 of a manifold 91 is connected to a nitrogen cylinder 21 during an airtightness test, to a vacuum pump 22 during a vacuum drawing operation, and to a refrigerant filling operation during a refrigerant charging operation. A cylinder 23 was connected, and a refrigerant collector 25 was connected during refrigerant recovery work.

However, the refrigerant work may be performed continuously, and equipment related to the refrigerant work (hereinafter referred to as refrigerant work-related equipment) such as the refrigerant collector 25, the nitrogen cylinder 21, the vacuum pump 22, the refrigerant filling cylinder 23, etc. ) was troublesome.

For example, after connecting the refrigerant recovery machine 25 to the manifold 91 and performing refrigerant recovery work, the nitrogen tank is reconnected to the manifold 91, the valve of the manifold is closed after nitrogen pressurization, and the pressure after being left at the specified pressure for the specified time Based on the amount of descent, an airtightness test is performed to check for any leaks in the piping. After confirming that there are no leaks in the airtightness test, the nitrogen gas is removed, and the vacuum pump is connected to the manifold 91 to perform vacuuming work. (In some cases, after removing the air, close the manual valve of the manifold, leave it for a specified time, and then check the airtightness with negative pressure to see if the vacuum can be maintained.) and evacuate the piping. After that, the refrigerant filling cylinder 23 can be reconnected to the manifold 91 and the refrigerant charging operation can be performed.

Therefore, the refrigerant work support device 1 of the present embodiment has a plurality of ports each provided with a valve and a mechanism for automatically controlling the valves so that refrigerant work can be performed while a plurality of refrigerant-related devices are connected to the manifold. I'm trying to set up.

<Appearance>
1 to 7 show the appearance of a refrigerant work support device 1 according to this embodiment. FIG. 1 is a perspective view of a refrigerant work support device 1. FIG. FIG. 2 is a front view of the refrigerant work support device 1. FIG. FIG. 3 is a rear view of the refrigerant work support device 1. FIG. FIG. 4 is a top view of the refrigerant work support device 1. FIG. FIG. 5 is a bottom view of the refrigerant work support device 1. FIG. FIG. 6 is a side view of the refrigerant work support device 1. FIG. FIG. 7 is a cross-sectional view of the refrigerant work support device 1 of FIG. 6 taken along the line AA.

The refrigerant work support device 1 is provided with six ports 131 to 136 outside the housing 11, and a purge port (not shown, hereinafter referred to as a discharge port) is provided separately. A display unit 12 such as a touch panel display is provided on the front surface of the refrigerant work support device 1 . In this embodiment, the display unit 12 is capable of receiving input of information from the coolant operator through a touch panel or the like.

Each port 131 to 136 and the outlet are provided with respective valves. As shown in FIG. 7, the refrigerant work support device 1 has seven valves SV1 to SV7. The ports 131 and 132 are provided with motor-operated valves SV1 and SV2, respectively, the ports 133 to 136 are provided with solenoid valves SV3 to SV6, and the outlet is provided with a solenoid valve SV7. be provided. A control unit 16 for controlling the valves SV1 to SV7 is arranged inside the housing 11 . Valves SV1 to SV7 are attached to and communicate with manifold 13 . In this embodiment, the manifold 13 has a form in which the first manifold 14 and the second manifold 15 are connected, but the manifold 13 may be formed as an integral unit.

As shown in FIG. 8, for refrigerant work, a port 131 connected to the valve SV1 and a port 132 connected to the valve SV2 are connected to a refrigerant unit 31 such as an air conditioner. Specifically, the port 131 is connected to the service port 311 on the low pressure side, and the port 132 is connected to the service port 312 on the high pressure side. Ports 131 and 132 are provided with pressure sensors 17 and 18, respectively.

A vacuum pump 22 can be connected to the port 133 provided with the valve SV3. A vacuuming operation is performed by opening the valve SV3 and operating the vacuum pump 22 .

A nitrogen cylinder 21 can be connected to a port 134 provided with a valve SV4. In the airtightness test, after opening the valve SV4 and injecting nitrogen from the nitrogen cylinder 21 to raise the pressure, the valve SV4 is closed and the pass/fail can be determined by the degree of pressure drop measured using the pressure sensors 17 and 18. can.

The refrigerant filling cylinder 23 can be connected to the port 135 provided with the valve SV5. In the refrigerant charging operation, the valve SV5 is opened to operate the refrigerant charging cylinder 23 to inject the refrigerant into the refrigerant unit 31 . A refrigerant cylinder 23 is placed on a charging scale 24 , and the charging scale 24 measures the weight of the refrigerant cylinder 23 . The weight change measured by the charging scale 24 allows the amount of refrigerant charged to be calculated.

The refrigerant collector 25 can be connected to the port 136 provided with the valve SV6. In the refrigerant recovery operation, the refrigerant is extracted from the refrigerant unit 31 and recovered in the recovery cylinder 26 by opening the valve SV6 and operating the refrigerant recovery device 25 .

The valve SV7 communicates with the outside of the manifold 13 through a discharge port, and when the valve SV7 is opened, the fluid existing inside the manifold 13 is discharged to the outside through the discharge port.

The valves SV1 to SV7 are controlled by the control unit 16, and the valves are opened and closed according to the refrigerant operation. be able to.

FIG. 9 is a diagram for explaining signals input/output to/from the control unit 16. As shown in FIG. Signals from the pressure sensors 17 and 18 (hereinafter referred to as pressure signals) are input to the controller 16 . Further, the controller 16 outputs a signal for instructing opening/closing of the valves (hereinafter referred to as an opening/closing signal) to the electric valves SV1 and SV2 and the solenoid valves SV3 to SV7. The valves SV1 to SV7 are opened and closed according to an open/close signal from the controller 16. FIG.

From the charging scale 24 , a signal indicating the weight of the object placed thereon (a load cell signal is assumed in this embodiment, but other signals may be used) is input to the controller 16 . . The controller 16 can calculate the amount of refrigerant discharged from the refrigerant cylinder 23 as the amount of refrigerant charged in the refrigerant unit 31 based on the load cell signal from the charging scale 24 .

The control unit 16 is also connected to the display unit 12 and can display a message on the display unit 12 . Further, in this embodiment, the display unit 12 also serves as an input device, and can receive information from the display unit 12 . The control unit 16 is also connected to a buzzer (not shown) provided in the refrigerant work support device 1, so that the control unit 16 can operate the buzzer.

<Action>
The operation of the refrigerant work support device 1 of this embodiment will be described below. 10A and 10B are diagrams for explaining the operation of the refrigerant work support device 1. FIG.

The control unit 16 outputs to the display unit 12 a message instructing to input the refrigerant work to be performed (S31), and when the refrigerant work input by the refrigerant worker is "airtightness test" (S32: airtightness test ), the process shown in FIG. 11 is executed (S33). If the input refrigerant work is "vacuum" (S32: vacuum), the process shown in FIG. 13 is executed (S35). If the entered refrigerant work is "refrigerant charge" (S32: refrigerant charge), the process shown in FIG. 14 is executed (S37). If the entered refrigerant work is "refrigerant recovery" (S32: refrigerant recovery), the process shown in FIG. 15 is executed (S39).

<Airtightness test>
FIG. 11 is a diagram for explaining the flow of processing related to the airtightness test. When performing the airtightness test, it is assumed that the nitrogen cylinder 21 is connected to the port 134 provided with the valve SV4.

The control unit 16 receives inputs of the airtight pressurization pressure, the airtight pressurization time, and the airtight determination threshold via the display unit 12 (S331). The controller 16 opens the valves SV1, SV2 and SV7 (S332). It is assumed that the valves SV3 to SV6 are closed. The controller 16 waits until the pressures of both the pressure sensors 17 and 18 become zero (S333: NO). After the pressure becomes zero (S333: YES), the controller 16 closes the valve SV7 (S334), opens the valve SV4 provided at the port 134 connected to the nitrogen cylinder 21, and the nitrogen from the nitrogen cylinder 21 is released. The manifold 13 and refrigerant unit 21 are filled (S335). The control unit 16 determines whether or not the pressure acquired from the pressure sensors 17 and 18 has reached the airtight pressurizing pressure (S337) until timeout occurs (S336: NO). If the airtight pressurization pressure has not been reached (S337: NO), the process returns to step S336. When the time-out occurs before the pressure reaches the airtight pressurization pressure (S336: YES), the control unit 16 operates a buzzer (not shown) to notify that the pressure increase has timed out (S338), and the pressure increases. A warning message is displayed on the display unit 12 to the effect that it has not been performed (S339), and the process ends.

When the pressure obtained from the pressure sensors 17 and 18 reaches the set airtight pressurization pressure (S337: YES), the control unit 16 closes the valves SV1, SV2 and SV4 (S340), and then closes the valve SV7. It is opened for 5 seconds to purge (S341). The control unit 16 waits until the set airtight pressurization time elapses (S342: NO), and when the airtight pressurization time elapses (S342: YES), the pressure is obtained from the pressure sensors 17 and 18 (S343).

If the pressure drop is within the permissible range, that is, if the value obtained by dividing the pressure measured by the pressure sensors 17 and 18 by the airtight pressurization pressure is equal to or greater than the airtight determination threshold (S344: YES), the control unit 16 Then, it outputs to the display unit 12 that it has passed the airtightness test (S345), opens the valve SV7 to purge the nitrogen gas (S346), and when the pressure from the pressure sensors 17 and 18 becomes zero (S347: YES). , terminate the process.

On the other hand, if the pressure drop exceeds the allowable range, that is, if the value obtained by dividing the pressure measured by the pressure sensors 17 and 18 by the airtight pressurization pressure is less than the airtight determination threshold value (S344: NO), leakage confirmation processing (S348). FIG. 12 is a diagram for explaining the flow of processing related to confirmation of leakage. The control unit 16 opens the valves SV1 and SV2 (S3481), and 0.5 seconds later, opens the valve SV4 (S3482) to inject nitrogen from the nitrogen cylinder 21 into the refrigerant unit 31. When the pressure obtained from the pressure sensors 17 and 18 reaches the airtight pressurization pressure (S3483: YES), the control unit 16 closes the valve SV4 (S3484), and displays the display unit 12 to confirm the location of the leak. An instructing message is displayed (S3485). A refrigerant operator can, for example, use a bubble or detector to locate the leak and make repairs or the like as necessary. The controller 16 can open the valves SV1, SV2 and SV7 to purge the charged nitrogen according to instructions from the refrigerant operator (S3486). As described above, it is possible to inspect the leak location.

<Evacuation>
FIG. 13 is a diagram for explaining the flow of processing related to the evacuation work. It is assumed that the vacuum pump 22 is connected to the port 133 provided with the valve SV3 when vacuuming is performed.

The control unit 16 receives inputs of the evacuation time, the initial confirmation time, the initial confirmation pressure, the completion confirmation time, and the completion confirmation pressure via the display unit 12 (S351). It should be noted that the end confirmation pressure may be set to a predetermined vacuum negative pressure value.

The controller 16 opens the valves SV1, SV2 and SV7 (S352). It is assumed that the valves SV3 to SV6 are closed. The controller 16 waits until the pressures of both the pressure sensors 17 and 18 become zero (S353: NO). After the pressure becomes zero (S353: YES), the controller 16 closes the valve SV7 (S354) and opens the valve SV3 provided at the port 133 to which the vacuum pump 22 is connected (S355).

Here, the vacuum pump 22 is started (S356). It should be noted that the control unit 16 and the vacuum pump 22 may be connected to send a signal from the control unit 16 to the vacuum pump 22 to start the vacuum pump 22 . Before the initial confirmation time elapses (S357: NO), the pressure does not reach the initial confirmation pressure (S358: NO), and if the initial confirmation time elapses (S357: YES), a leak occurs. is displayed on the display unit 12 (S359), and the process ends.

If the pressure reaches the initial confirmation pressure (S358: YES) before the initial confirmation time elapses (S357: NO), the control unit 16 causes the valve to SV1, SV2 and SV3 are closed (S361). Here, the vacuum pump 22 is stopped (S362). The vacuum pump 22 is stopped by connecting the control unit 16 and the vacuum pump 22 and sending a signal from the control unit 16 to the vacuum pump 22, or by the control unit 16 shutting off the outlet of the vacuum pump 22. You may make it

After waiting until the end time elapses (S363: YES), if the pressure falls below the end confirmation pressure (S364: NO), the process proceeds to step S359, and the display unit 12 displays that a leak has occurred. (S359). If the pressure is equal to or higher than the end confirmation pressure (S364: YES), the process ends normally.

As described above, a large leak (S358: NO, S357: YES) in which pressure is lost in a short time is confirmed, and a slow leak (S364: NO) in which pressure is gradually lost is confirmed. It can be confirmed that the evacuation has been reliably performed.

<Refrigerant charging>
FIG. 14 is a diagram for explaining the flow of processing related to refrigerant charging work. When the refrigerant charging operation is performed, the refrigerant charging cylinder 23 is connected to the port 135 provided with the valve SV5.

The control unit 16 receives inputs of a filling amount threshold, a pressure equalization confirmation time, and a pressure equalization confirmation threshold via the display unit 12 (S371).

The controller 16 opens the valves SV1, SV2 and SV5 (S372). It is assumed that valves SV3, SV4, SV6 and SV7 are closed. Here, the refrigerant cylinder 23 is opened (S373), and the refrigerant from the refrigerant cylinder 23 is injected into the refrigerant unit 31 through the manifold 13.

The control unit 16 receives the load cell signal from the charging scale 24 (S374), and calculates the amount of refrigerant charged in the refrigerant unit 31 (filling amount) based on the load cell signal (S375). The control unit 16 records the amount of change in the filling amount per unit time in a recording medium (not shown) such as a memory, and determines whether or not the amount of refrigerant that is equal to or greater than the pressure equalization confirmation threshold has moved during the pressure equalization confirmation time. determines whether or not pressure equalization (state in which the output pressure from the refrigerant cylinder 23 and the pressure on the high pressure side of the refrigerant unit 31 match) is reached (S376). (S376: YES), a message is displayed on the display unit 12 instructing to operate the refrigerant unit 31, close the service valve on the high pressure side of the refrigerant unit 31, and throttle the service valve on the low pressure side (S377). When the operator works according to this message, it becomes possible to move the refrigerant in the manifold 13 from the low pressure side of the refrigerant unit 31 to the refrigerant unit 31 .

If the amount of refrigerant charged into the refrigerant unit 31 is less than the threshold amount of charge (S378: NO), the process from step S374 is repeated. If the calculated filling amount is equal to or greater than the filling amount threshold (S378: YES), the controller 16 closes the valves SV1, SV2 and SV5 (S379). Here, the refrigerant charging cylinder 23 is also closed (S380). Here, the control unit 16 may display on the display unit 12 a message instructing to close the refrigerant cylinder 23 so that the operator closes the refrigerant cylinder 23, or the refrigerant cylinder 23 may be electrically operated. A valve or an electromagnetic valve may be provided, and this valve may be connected to the control unit 16 so that the control unit 16 controls the opening and closing of the refrigerant filling cylinder 23 . The refrigerant operator confirms the operation of the refrigerant unit 31 (S381), and if the amount of refrigerant charged is insufficient, instructs the display unit 12 of the refrigerant work support device 1 to charge, and the control unit 16 , the valves SV1, SV2 and SV5 are opened accordingly, and the valves SV1, SV2 and SV5 are closed according to instructions from the refrigerant operator (S382). The refrigerant charging operation is performed in this manner.

After the refrigerant unit 31 is completely charged with the refrigerant, the control unit 16 opens the SV 6 (S383), displays on the display unit 12 a message instructing to start the refrigerant recovery device 25, and starts the refrigerant recovery device 25. Start up (S384). It should be noted that the refrigerant recovery machine 25 and the control unit 16 may be connected and the refrigerant recovery machine 25 may be operated by a signal from the control unit 16 . As a result, the refrigerant remaining in the manifold 13 can be recovered, and the outflow of the refrigerant can be reliably prevented.

<Refrigerant recovery>
FIG. 15 is a diagram illustrating the flow of processing related to refrigerant recovery work. It is assumed that the refrigerant collector 25 is connected to the port 136 provided with the valve SV6 when the refrigerant recovery operation is performed.

The controller 16 opens the valves SV1, SV2 and SV6 (S391). It is assumed that valves SV3 to SV5 and SV7 are closed. Here, the refrigerant collector 25 is activated (S392). It should be noted that the refrigerant recovery machine 25 and the control unit 16 may be connected and the refrigerant recovery machine 25 may be operated by a signal from the control unit 16 . When the control unit 16 receives an instruction to end the refrigerant recovery work via the display unit 12 (S393: YES), the control unit 16 ends the process.

As described above, according to the refrigerant work support device 1 of the present embodiment, the plurality of valves provided in the manifold 13 can be automatically controlled to open and close. While connected, the refrigerant work can be performed by opening the valve of the refrigerant work-related equipment to be used. Therefore, it is possible to reduce the trouble of replacing the equipment related to refrigerant work.

In addition, according to the refrigerant work support device 1 of the present embodiment, since the valves can be automatically opened and closed by the control unit 16, it is possible to prevent mistakes in the order and timing of opening and closing the valves. , the refrigerant work can be performed reliably.

In addition, the display unit 12 provided on the front surface of the refrigerant work support device 1 of the present embodiment displays work instructions related to the refrigerant work, and the worker can perform the work while looking at the explanation displayed on the display unit 12. Therefore, even a worker unfamiliar with refrigerant work can reliably perform the refrigerant work, and even an inexperienced worker can perform maintenance of the refrigerant unit 31 .

Although the present embodiment has been described above, the above-described embodiment is intended to facilitate understanding of the present invention, and is not intended to limit and interpret the present invention. The present invention can be modified and improved without departing from its spirit, and the present invention also includes equivalents thereof.

For example, in the present embodiment, one refrigerant work is designated at the time of operation, but a plurality of refrigerant work may be designated. Alternatively, a work combining a plurality of refrigerant works may be specified. Furthermore, the order of a plurality of refrigerant tasks may be specified. In this case, the processes shown in FIGS. 11 to 15 may be executed in the designated order.

Further, in the present embodiment, only the minimum information to be displayed on the display unit 12 has been described, but various types of information related to refrigerant work can be displayed. For example, the control unit 16 can display a description of the refrigerant work on the display unit 12 when the refrigerant work is specified. The control unit 16 can also display the progress of the processing shown in FIGS. 11 to 15 on the display unit 12. FIG. For example, the control unit 16 can display the pressure obtained from the pressure sensors 17 and 18 and the filling amount calculated based on the load cell signal received from the charging scale 24 on the display unit 12 . In addition, the control unit 16 displays on the display unit 12 an instruction to the refrigerant worker to operate the nitrogen cylinder 21, the vacuum pump 22, the refrigerant filling cylinder 23, the refrigerant recovery device 25, etc. regarding the refrigerant work. can also

Further, in this embodiment, in the refrigerant charging operation, the flow rate (charging speed) of the refrigerant moving from the refrigerant charging cylinder 23 to the refrigerant unit 31 is constant, but the charging speed may be lowered at the end. . FIG. 16 is a diagram showing a modified example of the operation of the refrigerant work support device 1 related to the refrigerant charging work shown in FIG. 4 shows an example of processing for making adjustments so that In the example of FIG. 16, when the amount of refrigerant charged into the refrigerant unit 31 reaches a value obtained by subtracting a preset value from the threshold value of the amount of charge (S401: YES), the controller 16 closes SV5. , and opens after a short period of time to reduce the filling speed of the refrigerant in the refrigerant unit 31 (the amount of refrigerant transferred per unit time) (S402). The momentum of the refrigerant discharged from the refrigerant charging cylinder 23 is often strong, and after receiving the load cell signal from the charging scale 24 immediately before reaching the charging amount threshold, until the next load cell signal is received, It can happen that the fill volume exceeds the fill volume threshold. Therefore, by lowering the charging speed slightly before reaching the charging amount threshold value, it is possible to charge the refrigerant so as to accurately reach the charging amount threshold value.

Also, in the present embodiment, it is described that the airtightness test, vacuuming, refrigerant charging, and refrigerant recovery are performed as separate operations, but it is also possible to perform two or more operations continuously. In this case, a mode in which a plurality of operations are performed continuously may be set in advance and the operator may specify the mode, or the operator may specify the operations to be performed and their order. good too.

1 refrigerant work support device 11 housing 12 display unit 13 manifold 14 first manifold 15 second manifold 16 control unit 17 pressure sensor 18 pressure sensor 21 nitrogen cylinder 22 vacuum pump 23 refrigerant charging cylinder 24 charging scale 25 refrigerant recovery machine 26 Recovery cylinder SV1 valve SV2 valve SV3 valve SV4 valve SV5 valve SV6 valve SV7 valve

Claims (7)

a manifold having two first openings with two pressure sensors and a plurality of second openings to which at least two of a vacuum pump, a refrigerant cylinder, a nitrogen cylinder and a refrigerant collector are connected;
first and second valves provided in the first and second openings, respectively;
a control unit capable of controlling each of the first and second valves such that only one of the second openings opens at the same time as the first opening;
with
At least the nitrogen cylinder is connected to the second opening,
When the control unit receives an instruction for an airtightness test,
Open each of the first valves and an input valve to which the nitrogen cylinder is connected among the second valves;
measuring a first pressure based on a signal from the pressure sensor;
closing the first valve and the input valve when the measured first pressure reaches a preset specified value;
measuring a second pressure based on the signal from the pressure sensor after a preset time;
Determining whether the airtightness test has passed or failed based on whether the difference between the first and second pressures is equal to or less than a preset threshold;
A refrigerant work support device characterized by : The refrigerant work support device according to claim 1,
The manifold further has a third opening for discharging the fluid in the manifold to the outside,
each of the third openings is provided with a third valve;
The controller can control each of the second and third valves such that only one of the second and third valves opens at the same time as the first opening. to be,
A refrigerant work support device characterized by: The refrigerant work support device according to claim 1 ,
At least the vacuum pump is connected to the second opening,
When the control unit receives an instruction for evacuation work,
opening each of the first valves and the vacuum valve of the second valve to which the vacuum pump is connected;
If the negative pressure indicated by the measurement value from the pressure sensor does not reach a predetermined threshold value by the time a preset first time elapses, announcing that a leak has occurred,
A third preset time elapses after closing the first valve and the vacuum valve when a second preset time longer than the first time elapses. Notifying that a leak has occurred when the negative pressure indicated by the measurement value from the pressure sensor falls below the predetermined threshold value by
A refrigerant work support device characterized by: The refrigerant work support device according to claim 1 ,
At least the refrigerant cylinder is connected to the second opening,
The control unit is connected to a device that outputs a signal indicating the amount of refrigerant discharged from the refrigerant cylinder,
When the control unit receives a refrigerant charging instruction,
Open each of the first valves and a refrigerant valve to which the refrigerant cylinder is connected among the second valves,
receive the signal from the device;
calculating the filling amount of the refrigerant based on the signal;
Closing the first valve and the refrigerant valve when the calculated charging amount is equal to or greater than a preset threshold;
A refrigerant work support device characterized by: The refrigerant work support device according to claim 4 ,
High-pressure side and low-pressure side ports of an air conditioner are connected to the first opening,
The control unit outputs a signal instructing to close the high-pressure side port when the charging amount reaches or exceeds a set value smaller than the threshold value, and the refrigerant cylinder to the low-pressure side port is discharged. controlling the first valve so that the flow rate of the refrigerant is reduced;
A refrigerant work support device characterized by: The refrigerant work support device according to claim 4 ,
The refrigerant collector is also connected to the second opening,
The control unit closes the first valve and the refrigerant valve when the charging amount becomes equal to or greater than the threshold value, and then the refrigerant collector of the second valve is connected. opening a recovery valve to recover the refrigerant remaining in the refrigerant work support device;
A refrigerant work support device characterized by: The refrigerant work support device according to claim 5 ,
At least the refrigerant collector is connected to the second opening,
When the control unit receives a refrigerant recovery operation instruction,
opening each of the first valves and a recovery valve among the second valves to which the refrigerant recovery device is connected;
closing the first valve and the recovery valve in response to instructions;
A refrigerant work support device characterized by: