JPS6129631A - Fan coil unit - Google Patents

Abstract

PURPOSE:To reduce pressure loss at a heat exchanger and at the same time realize a low cost fan coil unit by a structure wherein space cooling pipings and space heating pipings are respectively connected through a motorized three-way valve to a piping for both space heating and cooling by one at the inlet side of the heat exchanger and through a thermostatic three- way valve to a piping for both space heating and cooling by one at the outlet side of the heat exchanger. CONSTITUTION:Pipings for both space heating and cooling by one 23 and 24 are respectively and singly connected to the inelt side and outlet side of the heat exchanger 1 of a fan coil unit. A space cooling piping 25 and a space heating piping 26 are branched through a motorized three-way valve 29 from the piping for both space heating and cooling by one 23 connected to the inlet side of the heat exchanger. On the other hand, a space cooling piping 27 and a space heating piping 28 are branched through a thermostatic three-way valve 38 from the piping for both space heating and cooling by one connected to the outlet side of the heat exchanger. When space cooling is intended, the motorized three-way valve 29 opens the space cooling piping 25 and the space cooling piping 26, both of which are connected to the inlet side of the heat exchanger. In addition, the thermostatic three-way valve 30 provided at the outlet side of the heat exchanger opens either one of the pipings 27 and 28 connected to the outlet side of the heat exchanger by sensing low temperature/high temperature heat transfer medium.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a fan coil unit for an air conditioner, and particularly to a fan coil unit with a 4-pipe system that can be switched by operating an air conditioning/heating switch! be.

[Prior art]

A conventional fan coil unit as described above will be explained with reference to FIGS. 1 to 4.

In these figures, reference numeral 1 denotes a heat exchanger composed of copper pipes 2 for the current chamber, copper pipes 3 for heating, integral fins 4 for both cooling and heating, and side plates 5 located at both ends of the four rows of fins. The copper tubes 2 and 3 pass through plate-shaped fins 4 and side plates 5 that are arranged parallel to each other at equal pitches to form a heat medium flow path.

6 and 7 are inlet and outlet headers for cooling, and 8 and 9 are inlet and outlet headers for heating. 10 and 11 are an inlet pipe and an outlet pipe for cooling, and 12 is an electric two-way valve for cooling provided in the inlet pipe 10. 1
3 and 14 are inlet piping and outlet piping for heating;
5 is an electric two-way valve for heating provided in the inlet pipe 13. 16 is an operation switch provided in the fan coil unit that can switch between air conditioning and heating; 17. ．． 18 is an electric motor, a fan,
19 is a drain pan that receives condensed water from the heat exchanger 1 during cooling operation, 20.21 is a filter and a blowout grill;
22 is a fan coil unit incorporating a heat exchanger 1, an electric motor 17.7, a drain pan 19, a filter 20, a blow-off grill 21, and the like.

Next, the operation of the conventional fan coil unit configured as described above will be explained. When the operation switch 16 is turned on, the electric motors 17 and 18 rotate to generate wind, and the air passes through the heat exchanger 1 from the filter 20 and is blown out through the blow-off grill 21. At this time, when the air conditioning/heating selector switch is set to the cooling side, the electric two-way cooling valve 12 is opened, the electric two-way heating valve 15 is closed, and only cold water flows into the cooling copper pipe 2 of the heat exchanger 1. Cooling operation is performed by flowing through the air. Conversely, when the air conditioning/heating selector switch is set to the heating side, the electric two-way cooling valve 12 is closed, the electric two-way heating valve 15 is open, and only hot water flows through the heating steel pipe 3 of the heat exchanger 1. heating operation is performed.

Incidentally, recently, there have been an increasing number of fan coil units incorporating a 4-vibe system heat exchanger 1 that can perform cooling or heating operation simply by operating the operation switch 16 built into the fan coil unit that can switch between air conditioning and heating. ing.

This type of fan coil unit is an all-season hydraulic air conditioning system that simultaneously supplies cold water and hot water using a heat pump heat source machine or a combined heat source ff1 of a chiller and a boiler (both not shown).
For example, depending on the time of day or night, the weather, etc., cooling and heating operations can be switched by manually operating a switch on the fan coil unit.

In the case of a conventional fan coil unit, if heating capacity is important, the copper pipes 2 for cooling may be arranged in one row and the copper pipes 3 for heating may be arranged in two rows. If high capacity is required for both, various cases may be used, such as a heat exchanger with two rows of copper pipes 2 and 3 for cooling and heating, for a total of four sides. This heat exchanger is also used for cooling.

Because the fins 4 are used in common during heating, the capacity is higher than that of other 4-vib systems, which are double coils, that is, heat exchangers that combine independent cooling heat exchangers and heating heat exchangers. However, only the fins are shared, and in order to ensure capacity, it is necessary to increase the number of rows of copper tubes, which increases costs and increases the pressure loss of the heat exchanger. There was a problem.

[Summary of the invention]

This invention is an attempt to solve the problems of the conventional ones as described above, and the piping for both cooling and heating is connected to the inlet and outlet sides of the heat exchanger, and the piping for both cooling and heating is connected to the inlet side of the heat exchanger. Standard type heat exchange for both cooling and heating is achieved by connecting the cooling and heating piping on the outlet side via the electric three-way valve to the cooling and heating piping, respectively, via the temperature switching three-way valve. The purpose of the present invention is to provide a 7-uncoil unit with a 4-vib system that allows the use of a 4-vib system.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 5 to 8.

In these figures, 1 is also a heat exchanger, and heat exchanger 1
This is a normal type for both cooling and heating, which has steel pipes 2a and fins 4a for both cooling and heating.

23.24 is a cooling/heating pipe connected to the copper pipe 2a on the inlet side and outlet side, respectively. 25.26 is a cooling/heating pipe 23 on the inlet side connected to the air conditioner via an electric three-way valve 29. 27. 28 is a pipe for cooling and heating on the population side which is branched off from the cooling and heating pipe 24 on the outlet side, and a temperature switching three-way valve 3.
This is the cooling and heating piping on the outlet side that branches through 0. The temperature switching three-way valve 30 has an operating part 32, which expands and contracts in the axial direction due to heat, such as a metal bellows, positioned and installed in a valve housing 31, and truncated conical valve bodies 33, 34 are fixed to both ends of the operating part 32. The valve seats 35 and 36 with which these valve bodies 33 and 34 are in pressure contact are connected to the cooling and heating piping 27 of the valve housing 31.
28 side communication section, and a fluid with a large coefficient of thermal expansion is sealed in the operating section 32.The structure of this embodiment other than the above is different from the conventional structure shown in FIGS. 1 to 4. It is similar to that.

In the fan coil unit of the embodiment configured as described above, when the N-plate switch is turned on to the cooling side, the power on the inlet side is turned off.
! ! The two three-way valves operate so that the cooling pipe 25 is opened and the heating pipe 26 is closed, so that a low-temperature heat medium flows into the heat exchanger 1. Further, the temperature switching three-way valve 30 senses the temperature of the low-temperature heat medium coming out of the heat exchanger 1, and the operating part 32
is shortened in the axial direction, the cooling pipe w27 on the outlet side is opened, and the heating pipe 28 is closed, thereby performing a cooling operation.

Conversely, when the operation switch is turned to the heating side, the heating piping 26 on the inlet side is opened and the cooling piping 25 is closed. The three-way switching valve 30 senses the high-temperature heat medium and operates the operating part 32.
extends in the axial direction, and the heating pipe 28 on the outlet side is opened.
The cooling pipe 27 is operated to close, and heating operation is performed.

The operations of this embodiment other than those described above are the same as those of the conventional one shown in FIGS. 1 to 4.

The 4-pipe system fan coil unit according to this embodiment uses a simple heat exchanger in which the copper tubes 2a of the heat exchanger 1 are standard crab rows, and the external static pressure, air volume, and capacity satisfy the standard specifications. Moreover, the expensive electric three-way valve only needs to be used on the inlet side of the heat exchanger.

〔Effect of the invention〕

As explained above, the present invention provides a heat exchanger of a fan coil unit with one air conditioner on each of the inlet and outlet sides.
Connect the heating and cooling piping, and branch the cooling and heating piping from the cooling and heating piping on the inlet side through an electric three-way valve, and branch the cooling and heating piping from the cooling and heating piping on the outlet side through the temperature switching three-way valve. For cooling, the piping on the shoulder side is branched, and the above-mentioned electric three-way valve is operated by operating the air conditioning/heating selector switch, such as the one built into the operation switch installed in the fan coil unit. The cooling piping on the side opens and the heating piping closes, and during heating, the heating piping on the inlet and outlet sides opens and the cooling piping closes, so that the heat exchanger can perform both cooling and heating. A standard, sturdy heat exchanger for both heating and heating is sufficient, pressure loss can be reduced, and
The temperature 3-way valve on the outlet side of the heat exchanger senses low and high temperature heat medium and opens the cooling piping on the outlet side and the piping on the shoulder side, so it saves expensive electricity! ! ! The lJ3-way valve only needs to be provided on the inlet side, which also has the effect of reducing costs.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of the internal structure of a conventional fan coil unit, Fig. 2 is an enlarged sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is an explanatory diagram of the internal structure of a conventional fan coil unit.
4 is an enlarged front view of the heat exchanger and piping section of FIG. 1, and FIG. 5 is a 7T film unit heat exchanger according to an embodiment of the present invention. cross-sectional view of
Fig. 6 is a plan view of the heat exchanger shown in Fig. 5, Fig. 7 is a front view of the heat exchanger and piping section according to the second embodiment of the invention, and Fig. 8 is a front view of the heat exchanger and piping section according to the second embodiment of the invention. FIG. 3 is an enlarged cross-sectional view of the temperature switching three-way valve of the embodiment. 1... Heat exchanger, 2, 2a, 3... Copper tube, 4, 4a
...Fin, 26...Operation switch that can switch between air conditioning and heating.
ychi, 23゜24...Cooling/heating piping, 25.2
6...Inlet side cooling and heating piping, 27.28...
Outlet side C cooling and heating piping, 29...electric 3-way valve, 3
0...Temperature switching 3-way valve. Note that the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa (2 idiots) Figure 1 Figure 2 Figure 4 Figure 4 Figure 7 Figure 8 Procedural amendment (voluntary) 1. Indication of case Patent application No. 59-151506 No. 2
, Title of the invention Fan coil unit 3 Person making the amendment Representative Hitoshi Katayama Department 4 Agent 5 Subject of amendment 1) Detailed explanation column of the invention in the specification, Contents of the amendment 1) Specification path Page 2 In the 9th line, the statement "Both ends of fin 4 column" is corrected to "Both ends of fin 4 column".

Claims (1)

[Claims] One pipe for both cooling and heating is connected to the heat exchanger in the fan coil unit on the inlet and outlet sides, and one pipe for cooling and heating is branched from the pipe for cooling and heating on the inlet side via an electric three-way valve. Two pipes for heating and cooling on the outlet side,
It is equipped with two pipes for cooling and heating branched from the heating/heating pipe via a temperature switching three-way valve, and the electric three-way valve is operated by operating a heating/cooling switch provided in the fan coil unit. During cooling, the cooling pipes on the inlet and outlet sides are open and the heating pipes are closed, and during heating, the heating pipes on the inlet and outlet sides are open and the cooling pipes are closed. A fan coil unit characterized by: