JPH0643652Y2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial field of application The present invention relates to a multi-type air conditioner that cools and heats a plurality of rooms by connecting a plurality of ceiling-embedded indoor units in parallel to one outdoor unit. .

(B) Conventional technology In a multi-type air conditioner, the indoor units are installed at different heights and distances from the installation location of the outdoor unit, so there is a difference in height between each indoor unit and the indoor and outdoor units are installed. Since the length of the refrigerant pipe to be connected, the bending angle of this refrigerant pipe and the number of bends thereof are different, a difference occurs in the pipe resistance of each indoor unit. For this reason, there is a problem in that a non-uniform flow occurs during the cooling operation in which the liquid refrigerant is split and supplied to each indoor unit, resulting in a difference in the cooling capacity of each indoor unit.

As a countermeasure against this, an air conditioner in which a throttle portion is provided at each of two connection ports of a T-shaped branch pipe that branches the liquid-side refrigerant pipe so as to give a flow resistance to the refrigerant is disclosed in JP-A-60-114662. ing.

(C) Problems to be solved by the invention In the device disclosed in the above publication, the throttle portion is provided integrally with the T-shaped branch pipe, so that the T-shaped branch pipe itself is replaced when adjusting the flow resistance of the refrigerant. In addition, this replacement work is performed after the outdoor unit and the two indoor units are installed on site and the test run is performed. The welding portion between the liquid-side refrigerant pipe and the T-shaped branch pipe had to be removed, and the work was troublesome. Especially in the ceiling embedded type structure where the indoor unit is embedded in the ceiling space,
Since the T-shaped branch pipe is placed in an unspecified place inside the ceiling, the replacement work of the T-shaped branch pipe is extremely troublesome.

Moreover, since the difference in pipe resistance differs depending on the installation condition of each indoor unit, various types of T with different sizes of the two throttles are used.
There was a problem that the mold branch pipes had to be prepared.

The present invention provides an air conditioner that solves these problems.

(D) Means for solving the problem In the present proposal, the indoor unit connected to the liquid-side refrigerant pipe is provided with a pipe connector connected to the liquid-side refrigerant pipe, and the pipe resistance value of the liquid-side refrigerant pipe is adjusted. Accordingly, a squeezing tool detachably attached to the pipe connecting tool is provided.

(E) Action One of the multiple indoor units is embedded in the ceiling of the building, and the other is embedded in the interior of the descending ceiling, which is one step lower than this ceiling, through the ceiling holes to branch out from the outdoor unit installed outdoors. The liquid side refrigerant pipe and the gas side refrigerant pipe are connected. At this time, the piping connectors of the liquid-side refrigerant pipes provided in each indoor unit are screwed with the throttles having different flow resistances considering the pipe resistance difference from the connection ports of the pipe connectors, respectively, and then, Flare connection of the liquid side refrigerant pipe to the connection port. When the piping connection is completed and the cooling test operation is performed, if the liquid refrigerant splitting is bad, pump down operation is performed to store the refrigerant in the outdoor unit, and then insert a hand from the ceiling hole to insert it from the connection port of the pipe connector. When the liquid-refrigerant pipe is removed, the throttle in the pipe connector is extracted, and replaced with another throttle, the refrigerant distribution to each indoor unit is improved and the cooling capacity of each indoor unit is balanced.

(F) Embodiment FIG. 1 is a refrigerant circuit diagram of an air conditioner showing an embodiment of the present invention, in which (1) is a compressor (2), a four-way valve (3), an outdoor heat exchanger (4), and for cooling. Check valve (5) and heating pressure reducing element (6)
The outdoor units with built-in and (7a) (7b) respectively include the indoor heat exchangers (8a) (8b), the check valves (9a) (9b) for heating, and the pressure reducing elements (10a) (10b) for cooling. In the built-in indoor unit, these equipment parts are liquid side refrigerant pipes (13) (13a) (13b) and gas side refrigerant pipes (14) (14a) (14b) welded to the T-shaped branch pipes (11) (12). ) Are the units (1) (7
a) A refrigerant circuit is formed as shown by connecting to the open / close connecting valves (15) (16) fixed to (7b) and flare type piping connectors (17a) (17b) (18a) (18b) It is supposed to be done.

And, the pipe connectors (17a) (17b) connected to the liquid side refrigerant pipes (13a) (13b) are, as shown in FIG. 2 and FIG.
The mounting plate (19) has an annular groove (20) in which the mounting plate (19) is fitted, and the mounting plate (19) is fixed to the exterior plate (21) of the indoor unit (7a) (7b) by screwing (22). Nipple (2
3) and a flare nut (24) that connects the flared liquid-side refrigerant pipes (13a) (13b), and the pipe connection tools (17a) (17b) have this connection port (25). The space (29) into which the throttle (28) formed of the small diameter pipe (27) with the screw (26) is inserted into the end edge (30) of the screw (26) to seal the refrigerant. A step portion (31) is provided. (32) is the throttle (28) and the pipe connector (17
a) A notch groove into which a tool such as a flat-blade screwdriver fits when screwed into (17b), and (33a) (33b) are refrigerant pipes incorporated in the indoor units (7a) (7b), respectively.

FIG. 4 is a schematic structural diagram of the indoor unit (7a). The indoor unit (7a) has a ceiling (35) in which a ring-shaped indoor heat exchanger (8a) and a turbo fan (34) are built. A decorative panel (40) having a main body (37) embedded through a hole (36), a suction port (38) in the center, and outlets (39) (39) in the periphery, and which is attached to the lower surface of a ceiling (35). It consists of and. Incidentally, FIG. 4 shows only a part of the pipe connector (17a), the T-shaped branch pipe (11) and the liquid side refrigerant pipes (13) (13a) (13b). The other indoor unit (7b) also has a structure similar to that shown in FIG.

The air conditioner of the present invention is configured as described above. One indoor unit (7a) is placed inside the ceiling (35) of the building (41), and the other indoor unit (7b) is placed one step above this ceiling (35). The outdoor unit (1) and the liquid-side refrigerant pipes (13) (13a) (13b) and the gas-side refrigerant pipe (which are buried in the ceiling holes (36) inside the lowered ceilings (42) and installed outdoors respectively ( 14) Connect with (14a) (14b). At this time, the liquid side refrigerant pipe (13) provided in each indoor unit (7a) (7b)
a) (13b) pipe connection tools (17a) (17b), each of which has a throttle (28) with a different flow resistance in consideration of the pipe resistance difference, which is screwed into the connection port (25) and then inserted. (twenty five)
The liquid side refrigerant pipes (13a) and (13b) are flared. When this pipe connection is completed, a cooling test run is performed next to check whether the system operates normally. That is, when the four-way valve (3) is set to the solid line state and the compressor (2) is operated, the refrigerant discharged from the compressor (2) causes the four-way valve (3) -the outdoor heat exchanger (4)-
After flowing into the cooling check valve (5) -opening / closing connecting valve (15) -T-shaped branch pipe (11), the liquid is divided in this branch pipe (11) and one of the liquid refrigerants is a pipe connector (17a). -Air conditioning decompression element (10
a) -Indoor heat exchanger (8a) -Pipe connector (18a) and the other liquid refrigerant is the pipe connector (17b) -Cooling decompression element (10b) -Indoor heat exchanger (8b) -Piping Connector (18
b), and both of these gas refrigerants are T-shaped branch pipes (12)
After merging with each other, the cooling cycle is formed in which the flow goes to the open / close connecting valve (16) -four-way valve (3) and returns to the compressor (2).

As a result of such a cooling test operation, when it is found that the liquid refrigerant is not diverted to an appropriate amount in the T-shaped branch pipe (11) and the cooling capacity of each indoor unit (7a) (7b) is unbalanced, one opening and closing connection After closing the valve (15) and operating the compressor (2) to collect the refrigerant in the pipe into the outdoor unit (1), the other opening / closing connection valve (16) is closed. The so-called pump down operation is performed. After that, remove the decorative panel (40) of one or both of the indoor units (7a) (7b), insert a hand through the ceiling hole (36), remove the flare nut (24), and connect the pipe connection tool (17a) ( 17b) connection port (25) to liquid side refrigerant pipe (13a)
Remove (13b), pull out the diaphragm (28), and replace it with another diaphragm. Then, the air in the other pipes except the pipe in the outdoor unit (1) is removed by the air purging work, and the flare nut (24) is used again to re-liquefy the refrigerant pipes (13a) (13b).
When the pipes are connected to the pipe connectors (17a) and (17b) respectively, the pipe connection work is completed, and the liquid refrigerant in the T-shaped branch pipe (11) is shunted well, so that the indoor units (7a) and (7b) The cooling capacity becomes balanced.

After switching the four-way valve (3) to the broken line during heating operation, the refrigerant discharged from the compressor (2) flows to the four-way valve (3) -open / close connecting valve (16) -T-type branch pipe (12). , One of the gas refrigerants split by the branch pipe (12) is connected to the pipe connector (18
a) -Indoor heat exchanger (8a) -Heating check valve (9a) -Pipe connector (17a) and local gas refrigerant is pipe connector (18b) -Indoor heat exchanger (8b)- Check valve for heating (9
b) -flows to the pipe connection tool (17b), and after both of these liquid refrigerants merge in the T-shaped branch pipe (11), the on-off connection valve (15) -pressure reducing element for heating (6) -outdoor heat exchanger (4) -A heating cycle is formed, which flows to the four-way valve (3) and returns to the compressor (2). Even during such an operation, the liquid refrigerant is adjusted to have a flow rate according to the pipe resistance difference when passing through the restrictor (28) in the pipe connector (17a) (17b).
a) The heating capacity of (7b) becomes balanced.

(G) Effect of the Invention According to the present invention, in the multi-type air conditioner, the indoor unit is provided with the pipe connector that is connected to the liquid-side refrigerant pipe, and according to the pipe resistance value of the liquid-side refrigerant pipe, Since the pipe fitting is equipped with a restrictor that can be detachably attached, if the amount of refrigerant flowing through each indoor unit is unbalanced due to the difference in piping resistance, remove only the restrictor from the pipe connector and replace it with another restrictor. It is possible to balance the amount of refrigerant flowing through each indoor unit.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a refrigerant circuit diagram of an air conditioner, FIG. 2 is a sectional view of a pipe connector, FIG. 3 is an exploded sectional view of the pipe connector, and FIG. It is a schematic structure figure of an indoor unit. (1) ... Outdoor unit, (7a) (7b) ... Indoor unit, (13a) (13b) ... Liquid side refrigerant pipe, (17a) (17b) ...
… Piping connector, (25) …… connection port, (27) …… small diameter pipe, (28) …… squeezer.

Front page continuation (72) Inventor Haruaki Suzuki 180, Sakata, Oizumi-cho, Gunma-gun, Toyo Sanyo Electric Co., Ltd. In-house (72) Creator Masakazu Nakajima 180 Sakata, Oizumi-cho, Ora-gun, Gunma Tokyo Sanyo Electric Co., Ltd. (56) , U)

Claims (3)

[Scope of utility model registration request] 1. An air conditioner in which a plurality of indoor units are branched into one outdoor unit and connected in parallel by a liquid-side refrigerant pipe and a gas-side refrigerant pipe, wherein the indoor unit has the liquid-side refrigerant pipe. An air conditioner provided with a pipe connector connected to the pipe connector and a throttle device detachably attached to the pipe connector according to a pipe resistance value of the liquid-side refrigerant pipe. 2. The air conditioner according to claim 1, wherein the indoor unit is embedded in the ceiling of the building. 3. The air conditioner according to claim 1, wherein the restrictor is formed of a small-diameter pipe screwed into the connector from a connection port of the pipe connector.