JPS6041473Y2 - Anti-frost device in air ventilation fans - Google Patents

Description

[Detailed description of the invention] This invention relates to a frost prevention device for an air conditioning ventilation fan for preventing frost from forming on the heat exchanger of the air conditioning ventilation fan in a cold region.

Conventionally, as shown in Fig. 1, air conditioning ventilation fans have two separate air passages: an air supply system 101 that sucks in outside air and supplies it indoors, and an exhaust system 102 that sucks in indoor air and exhausts it to the outdoors. The air supply system 101 and the exhaust system 102 intersect in a heat exchanger 103 while remaining independent.

In such an air conditioning ventilation fan, depending on the air conditions on the two suction sides of the heat exchanger 103, condensation or frost may form inside the heat exchanger 103, causing ventilation problems in the heat exchanger 103. The lower limit is generally about -10°.

Therefore, in cold regions where the usage conditions are not met, it is necessary to preheat the intake air (outside air).

Preheating of the intake air is carried out by providing a heating device such as a heater or by mixing a portion of the exhaust air flow into the supply air flow, but the former requires an extra heater and associated components; The latter had problems such as incomplete ventilation and reduced efficiency.

The purpose of this invention is to be able to preheat outside air and send it to the heat exchanger without installing a heating device, and to prevent the mixing of the supply air flow and the exhaust air flow, thereby preventing frost formation on the heat exchanger even in cold regions. To provide a frost prevention device for an air conditioning ventilation fan, which can substantially prevent ventilation obstruction caused by air conditioning.

Next, the configuration of the present invention will be specifically explained based on an embodiment shown in the drawings.

The air conditioning ventilation fan as an application example of the present invention shown in FIG. In other words, a supply air blower 3 and an exhaust air blower 4 are respectively incorporated.

The outer box 1 has an air supply port 5 at the top of the front surface on the indoor side (right side in the drawing) for discharging outside air into the room, and an indoor suction port 6 at the bottom for sucking indoor air. , an indoor air exhaust lower is opened in the upper part of the front surface on the outdoor side (left side in the figure), and an outdoor suction port 8 for sucking in outside air is opened in the lower part.

The total heat exchanger 2 has two intersecting air passages arranged in multiple stages, and is mounted approximately in the center of the outer box 1 by several mounting plates 9.

The mounting plate 9 supports the total heat exchanger 2 and connects the space inside the outer box 1 to the indoor suction chamber S1 where the suction part of the exhaust passage of the total heat exchanger 2 faces, and the exhaust passage of the total heat exchanger 2. an outdoor-side discharge chamber S2 facing the discharge section of the total heat exchanger 2, an outdoor-side suction chamber S3 facing the inlet section of the air supply passage of the total heat exchanger 2, and a room side facing the discharge section of the air supply passage of the total heat exchanger 2. It is divided into a discharge chamber S4.

However, the indoor discharge chamber S4 and the outdoor discharge chamber S2, the indoor discharge chamber S4 and the indoor suction chamber S1, and the outdoor discharge chamber S2 and the outdoor suction chamber S3 are independent from each other by the mounting plate 9. However, the indoor suction chamber S1 and the outdoor suction chamber S3 are partitioned not by the mounting plate 9 but by a duct 10, which will be described later.

The air supply blower 3 is installed in the indoor discharge chamber S4 with its discharge port facing the air supply port 5, and the outdoor discharge chamber S2
An exhaust blower 4 is installed with its discharge port facing the exhaust lower.

The air supply blower 3 connects the outdoor suction port 8 to the outdoor suction chamber S3.
, the total heat exchanger 2, and the indoor discharge chamber S4 to form an air supply flow in the air supply passage leading to the air supply port 5.

Further, the exhaust blower 4 forms an exhaust flow in an exhaust passage from the indoor suction port 6 to the exhaust lower via the indoor suction chamber S1, the total heat exchanger 2, and the outdoor discharge chamber S2.

However, the above-mentioned air supply flow is particularly provided in the outdoor suction chamber S3 between the outdoor suction port 8 and the total heat exchanger 2, and connects the outdoor suction port 8 and the total heat exchanger 2. It passes through the inside of the preheating duct 10.

The preheating duct 10 is made of a material with good thermal conductivity, and its middle portion is arranged in a meandering manner in the indoor suction chamber S1 through which the exhaust flow passes, and is connected to the indoor air sucked from the indoor suction port 6. The outside air sucked in from the outdoor suction port 8 comes into thermal contact with the outside air in an independent state to exchange heat.

Therefore, even if the outside air that is conducted from the outdoor suction port 8 to the total heat exchanger 2 is extremely low temperature and would cause frost to form on the total heat exchanger 2, this outside air can pass through the duct 10. As a result, heat is received from the indoor warm air sucked in from the indoor suction port 6, preheated by the exhaust flow, and then conducted to the total heat exchanger 2, so that frost formation in the total heat exchanger 2 is prevented as much as possible. It will become.

Note that the duct 10 can also prevent dew condensation on the total heat exchanger 2 during cooling by its heat exchange function.

As is clear from the above description of the embodiments, the anti-frost device for the air conditioning ventilation fan of the present invention is designed to provide thermal conductivity between the outdoor air intake of the air supply passage and the introduction to the heat exchanger. This duct is installed in the part of the exhaust passage related to indoor air before reaching the heat exchanger, and the exhaust flow and supply air flow are connected through the duct before heat exchange by the heat exchanger. Since the heat exchanger exchanges heat between the heat exchangers, there is no mixing of the supply air flow and the exhaust air flow, which would lead to a decrease in efficiency, and the outside air introduced into the heat exchanger can be preheated without the need for additional heating devices such as heaters. It is possible.

This makes it possible to prevent troubles caused by frost on the heat exchanger in cold regions as much as possible, and expand the conditions under which the air conditioning ventilation fan can be used.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view showing a conventional air-conditioning ventilation fan in an installed state, and FIG. 2 is a vertical cross-sectional view showing an air-conditioning ventilation fan as an example of application of the present invention in an installed state. 1...Outer box, 2...Total heat exchanger, 3.
...Air supply blower, 4...Exhaust blower, 5...Air supply port, 6...Indoor suction port,
7...Exhaust port, 8...Outdoor intake port, 1
0...Duct, W...Wall structure.

Claims (2)

[Scope of utility model registration request] (1) In an air conditioning ventilation fan that simultaneously exhausts indoor air to the outdoors through an exhaust passage and supplies outside air into the room through an air supply passage through a built-in heat exchanger, A duct with good thermal conductivity is constructed between the outside suction port and the introduction part to the heat exchanger, and this duct is arranged in the exhaust passage before reaching the heat exchanger, so that the outside air flowing through the duct is 1. A frost prevention device for an air conditioning ventilation fan, characterized in that heat exchange between the air flow and the exhaust air flow is performed before conduction to the heat exchanger. (2) A frost prevention device for an air conditioning ventilation fan according to claim 1, wherein the duct is arranged in a meandering manner in the exhaust passage before reaching the heat exchanger.