JPH01244237A - Air conditioner - Google Patents

Abstract

PURPOSE:To prevent the generation of a drift current in the axial direction of a fan and to prevent the occurrence of surging phenomenon, by a method wherein ribs having a uniform height, width, and mounting pitch are formed on a part of the discharge side of the rear plate to a casing. CONSTITUTION:A rib 4 is measured to be height (b) from the inner surface of a rear plate 3 of a casing, width (t), and length (l), and the ribs are integrally molded at equal pitches of a distance (p). In this constitution, when in the case rib 4 is lacking, draft resistance on the suction side of a cross flow fan 1 is increased due to choking of a filter, a drift current W is about to be generated from the central part of the cross flow fan 1 in the direction of two end parts having low intake air resistance, and in turn surging phenomenon occurs. As against the above, since the ribs 4 are formed, in a section (two end parts) having low air resistance, the draft area of an air discharge passage 9 is decreased and throttled in a position being the downstream thereof, the drift current W flowing from a place having high air resistance to a place having low air resistance can be prevented from generation, resulting in the possibility to prevent the occurrence of surge phenomenon.

Description

[Detailed description of the invention] Industrial applications The present invention relates to an air conditioner.

BACKGROUND OF THE INVENTION Conventionally, various measures have been taken to prevent surging in air conditioners having cross-flow fans.

An example of the conventional air conditioner mentioned above will be described below with reference to the drawings.

FIG. 4 shows the structure of a ventilation circuit of an air conditioner having a conventional cross-flow fan. As shown in the figure, the suction side has a suction grill 5, a heat exchanger 6, etc., and a cross flow fan 1, a casing front plate 2, a casing rear plate 3, etc. constitute a ventilation circuit. In addition, cross flow fan 1
As shown in FIG. 5, an appropriate number of fan blocks 10 are connected to form a long fan rotor.

Problems to be Solved by the Invention However, in the configuration shown in FIG.
etc.) or the shape of the casing of the air flow path (for example, the casing front plate 2, the casing rear plate 3, etc.), the air resistance distribution on the fan suction side becomes uneven along the entire length of the cross-flow fan 1, and the cross-flow fan 1 When rotating, the air volume from the part with large intake air resistance is smaller than the air volume from the part with small resistance, and if a small-scale imbalance in air volume occurs at first, then the air from the large air volume will flow from the part with small air volume. As the wind is attracted, the difference in air volume becomes larger and larger.

By the way, due to the above-mentioned process, the air volume in a certain part became 6th.
Experiments have shown that when the temperature drops below point P on the characteristic curve in the figure, the part in question operates in a so-called unstable region, and a surging phenomenon occurs, causing the entire crossflow fan to generate vibrations and noise. .

The term "unstable region" as used herein refers to a region where the static pressure decreases as the air volume decreases, such as the portion to the left of point P on the characteristic curve--H in FIG.

Here, when the air volume decreases, the static pressure decreases, and a force acts on the fan in the direction of decreasing the air volume, so the force moves in a direction that promotes fluctuations in the air volume. Therefore, in this region, once the air volume fluctuates, it is not stable. The "stable region" in Figure 6 refers to the region on the right side of point P on the characteristic curve, where static pressure decreases as the air volume increases, and increases as the air volume decreases. A fan has arbitrary static pressure and air volume depending on the load condition, and operates stably by balancing the load at a single point.

In view of the above problems, the present invention aims to prevent surging of an air conditioner.

Means for Solving the Problems In order to solve the following problems, the present invention configures a ventilation circuit from a cross flow fan, a casing front plate, and a casing rear plate, and has a high-pitched part on the blowout side of the casing rear plate. difference,
Ribs are formed with uniform width and mounting pitch.

Effects The present invention has the above-described configuration, so even if there is an uneven distribution of suction resistance upstream of the suction port of the cross-flow fan, no drift occurs in the axial direction of the elongated fan rotor.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 3 of the accompanying drawings.

FIG. 1 is an internal sectional view of a separate type air conditioner during an indoor day.

As shown in the figure, there are a suction grill 5, a heat exchanger 6, etc. on the suction side, and a ventilation circuit is formed by a flow fan 1, a casing front plate 2, and a casing rear plate 3.

Ribs 4 of the present invention are formed on the inner surface of the casing rear plate 3 on the outlet side. Further, upper and lower deflection blades 7 and left and right deflection blades 8 are attached to the blowout side.

FIG. 2 is an enlarged perspective view of the air outlet portion of FIG. 1. As shown in the figure, ribs 4 are formed on the inner surface of the outlet side of the casing rear plate 3 (in this figure, the ribs 4 are attached to both ends on the Suita side, where the suction air resistance is low).

FIG. 3 is an enlarged view of the AA cross section in FIG. 2.

As shown in the figure, the ribs 4 have a height h, a width t, and a length e from the inner surface of the casing rear plate 3, and the ribs are integrally formed at equal pitches p.

According to this configuration, if there is no rib 4 and the ventilation resistance on the suction side of the crossflow fan 1 increases due to clogging of the filter, the flow will be biased from the center of the crossflow fan 1 toward both ends where the suction air resistance is low. W (indicated by arrow)
is likely to occur, which in turn causes the surging phenomenon described above. However, because of the presence of the rib 4, the ventilation area of the air Suita passage 9 is located downstream of the area (both ends) with low air resistance. This narrows the aperture and prevents the occurrence of drifting W from the side with higher suction air resistance to the side with lower suction air resistance.
As a result, the occurrence of surging phenomenon can be prevented.

In addition, conventionally, when surging occurs, a square polyethylene film or the like is pasted as a countermeasure, whereas the rib 4 is integrally molded with the casing rear plate a, which can reduce the cost and the number of man-hours for pasting the polyethylene film. Furthermore, if the width t of the rib 4 is made wide, sink marks will occur during molding, but since the width t of the rib 4 is kept to the maximum dimension that does not cause whiskers, there is no need to worry about this.

Effects of the Invention As described above, the air conditioner of the present invention prevents drifting in the axial direction of the fan, thereby preventing the occurrence of surging phenomenon, and creating a quiet and stable air conditioner without noise or vibration. Allows driving.

[Brief explanation of the drawing]

Fig. 1 is an internal sectional view of an indoor unit of a separate air conditioner according to an embodiment of the present invention, Fig. 2 is an enlarged perspective view of the air outlet of the air conditioner in the same room, and Fig. 3 is an enlarged perspective view of the air outlet of the same indoor unit. 4 is an internal sectional view of a conventional indoor unit, FIG. 5 is a plan view of a cross flow fan, and FIG.
The figure shows the characteristics of a crossflow fan. 1 Crossflow fan, 2 Casing front plate, 3
・Casing rear plate, 4 ribs, 5 heat exchanger. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
S + - Re cross flow fan 3rd TI! J)゛4

Claims (1)

[Claims] An air conditioner comprising a crossflow fan, a casing front plate, and a casing rear plate to form a ventilation circuit, and a rib having a uniform height, width, and mounting pitch is formed on a part of the outlet side of the casing rear plate.