JPH1194288A - Indoor unit of air-conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a squeak caused by the thermal expansion and contraction of front and base panels immediately after starting or stopping of air- conditioning operation and defrosting operation by providing a means for reduc ing contact surfaces on either or both of contact surfaces of the front and base panels. SOLUTION: Except a part of a contact surface 11 to a base panel 9 of a front panel 8, other greater part 12 is cut out. The thickness of the cutting out 12 is approximately 0.1-0.2 mm to meet the purpose. The cutting-out 12 is formed not only at the lower portion of the contact surface to the base panel 9 of the front panel 8, but also at both of right and left sides, thus the contact area can be reduced to 1/50-1/300. Incidentally it is also effective that the contact surface to the front panel 8 of base panel 9 is left to be uncut and other greater part may be cutout, further, a part of the contact surface of the front panel 8 and the base panel 9 is left, and other greater part may be cutout, thus stick slip vibration can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an indoor unit of an air conditioner.

[0002]

2. Description of the Related Art FIG. 6 shows an indoor unit of a conventional separation type air conditioner. Reference numeral 1 denotes a casing, which is formed by fitting a plastic front panel 8 and a base panel 9 together over the entire circumference.

[0003] 2 is a suction grill provided on the front surface of a front panel 8, 3 is a heat exchanger, 4 is a fan, 5 is a blow grill, 6 is a blow louver disposed on the blow grill 5, 7 is a heat exchanger 3 is a drain pan made of plastic disposed below.

During operation of the air conditioner, the fan 4 rotates,
Refrigerant from an outdoor unit (not shown) circulates through the heat exchanger 3. Then, as indicated by the solid arrow,
The heat is sucked into the casing 1 through the suction grill 2, and is cooled or heated by exchanging heat with the refrigerant in the process of flowing through the heat exchanger 3.

[0005] Next, the air is sucked into the fan 4 through the air passage 10 to be energized. Thereafter, the air is guided from the blow grill 5 to the blow louver 6 and blown into the room again.

[0006]

In the above-mentioned conventional indoor unit, the temperature of the heat exchanger 3 suddenly changes immediately after the start of the cooling operation, the heating operation, and the defrost operation or immediately after the operation is stopped. The front panel 8, the base panel 9, and the drain pan 7 which are in contact with the container 3 thermally expand or contract.

Then, relative displacement occurs at contact points A and B between the front panel 8 and the base panel 9 and at a contact point C between the front panel 8 and the drain pan 7, and based on the relative displacement, a stick-slip vibration (non-linear vibration) is generated. ) Occurs.

The stick-slip vibration excites the front panel 8, the base panel 9, and the drain pan 7, and a squeak sound is generated.

In order to cope with this, as shown in Japanese Patent Publication No. 60-39930 and Japanese Patent Laid-Open Publication No. Sho 61-280329, it has been proposed to sandwich a material having a small coefficient of friction between contact surfaces. This has the problem that the cost is high and the appearance is poor.

Further, as shown in Japanese Utility Model Publication No. 5-39373, a styrene-made drain pan is buried inside a metal box having a large number of cut-and-raised pieces protruding inward and the surface thereof is waterproofed. It has been proposed to cover with sheets, but this has the problem of increasing weight and cost.

[0011]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the gist of the first invention is that a plastic front panel and a base panel are fitted to each other. In an indoor unit of an air conditioner in which a heat exchanger, a drain pan, and the like are disposed inside a casing formed by combining, a contact surface of one or both of the contact surfaces of the front panel and the base panel is provided. An indoor unit of an air conditioner, characterized in that means for reducing the area is provided.

Another feature is that the above-mentioned means is constituted by cutting out a large part of the other surface while leaving a part of the contact surface of the front panel or the base panel.

Another feature is that the means is constituted by providing a large number of minute projections on the contact surface of the front panel or the base panel.

According to still another feature, the above means reduces the contact area between the front panel and the base panel by 1/50 to less.
To reduce it to 1/300.

The gist of the second invention is that a heat exchanger is disposed inside a casing composed of a plastic front panel and a base panel, and a plastic drain pan is provided below the heat exchanger with a front surface thereof. In the indoor unit of the air conditioner, which is disposed so as to be in contact with the front panel, the contact area is reduced on one or both of the front surface of the drain pan and the contact surface of the front panel contacting the drain pan. The indoor unit of the air conditioner is characterized in that the unit is provided.

Another feature is that the means is constituted by providing a large number of microprojections on a front surface of the drain pan or a contact surface of the front panel which comes into contact with the drain pan.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention is shown in FIG. 1, wherein (A) is a partial longitudinal sectional view showing a lower fitting portion between a front panel and a base panel, and (B) is a front panel. It is a perspective view of the lower part of FIG.

A large part 12 of the front panel 8 is cut away while leaving a part of the contact surface 11 of the front panel 8 with the base panel 9.
The thickness of the cut-off 12 is sufficient to be 0.1 to 0.2 mm. The cut-out 12 is formed not only below the contact surface of the front panel 8 with the base panel 9 but also on both left and right sides to reduce the contact area by 1/50. It has been reduced to ~ 1/300.

The front panel 8 of the base panel 9
It is also possible to cut off most of the other surface while leaving a part of the contact surface, and further, it is also possible to cut away most of the other surface while leaving a part of the contact surface of the front panel 8 and the base panel 9.

The vibration speed V of the stick-slip vibration is expressed by the following equation. _{VαP (μ S -μ m) ·} 1 / K where, P; dynamic friction coefficient of the contact surface; static friction coefficient mu _m of the contact surface; equivalent stiffness mu _S of the front panel 8; pressing force K of the front panel 8

[0021] However, in the actual product or to reduce the pressing force P, it is difficult or to increase the equivalent stiffness K, stick-slip vibrations by reducing the difference between the static friction coefficient mu _S and the dynamic friction coefficient mu _m Can be reduced.

The plastic material 2 the relationship between the difference Δμ of the contact area ratio and the static friction coefficient mu _S and the dynamic friction coefficient (high impact polystyrene) mu _m is shown, the contact area ratio, as apparent from FIG. 2 it is possible to reduce the difference Δμ of the static friction coefficient mu _S and the dynamic friction coefficient mu _m by reduced.

FIG. 3 (A) shows the result of measuring the squeak noise immediately after the heating operation was stopped.
It can be seen that the pulse-like squeaking noise has been greatly reduced.

FIG. 4 shows a second embodiment of the present invention. In the second embodiment, the contact surface 11 of the front panel 8 is provided with a large number of minute projections 13 to reduce the contact area with the base panel 9.

It is also possible to provide a large number of fine projections on the contact surface of only the base panel 9 or on both the contact surfaces of the front panel 8 and the base panel 9 so that the two contact each other via these projections. The operation and effect of the second embodiment are the same as those of the first embodiment.

FIG. 5 shows a third embodiment of the present invention. In the third embodiment, the drain pan 7
Are provided with a large number of minute projections 14 on the front surface, that is, the contact surface 15 with the front panel 8.

It is also possible to provide a large number of minute projections on the contact surface of the front panel 8 with the drain pan 7 or on both the contact surface of the front panel 8 and the drain pan 7 so that both contact with each other via these minute projections. it can. This third
The operation and effect of the third embodiment are the same as those of the first embodiment.

[0028]

According to the first aspect of the present invention,
Since one or both of the contact surfaces of the front panel and the base panel are provided with means for reducing these contact areas, the cooling and heating operations of the air conditioner, the front panel and the base immediately after the start or immediately after the defrost operation are stopped. A squeak noise caused by stick-slip vibration generated due to thermal expansion and contraction of the panel can be prevented.

The contact area between the front panel and the base panel can be reduced by leaving a part of the contact surface of the front panel or the base panel and cutting off most of the other parts.

The contact area between the front panel and the base panel can be reduced by a large number of small projections provided on the contact surface of the front panel or the base panel.

If the contact area between the front panel and the base panel is reduced to 1/50 to 1/300, squeak noise can be effectively prevented.

According to the second aspect of the present invention, the air conditioner is provided with a means for reducing the contact area on one or both of the front surface of the drain pan and the contact surface of the front panel which comes into contact therewith. The squeak noise caused by the stick-slip vibration generated based on the thermal expansion and contraction of the front panel and the drain pan immediately after starting or stopping the cooling operation, the heating operation, and the defrost operation can be prevented.

The contact area between the front panel and the drain pan can be reduced by providing a large number of minute projections on the front surface of the drain pan or the contact surface of the front panel that comes into contact with the front.

[Brief description of the drawings]

1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view of a lower fitting portion of a front panel and a base panel, and FIG.
FIG. 3 is a perspective view of a lower portion of the front panel.

FIG. 2 is a diagram showing a relationship between a difference between a coefficient of static friction and a coefficient of dynamic friction and an area ratio of a contact surface.

FIG. 3 shows a measurement result of a noise level immediately after the heating operation is stopped. (A) shows a result of the present invention, and (B) shows a result of a conventional method.

FIG. 4 is a perspective view of a lower portion of a front panel showing a second embodiment of the present invention.

FIG. 5 is a perspective view of a drain pan showing a third embodiment of the present invention.

FIG. 6 is a longitudinal sectional view of an indoor unit of a conventional air conditioner.

[Explanation of symbols]

 8 Front panel 9 Base panel 11 Contact surface 12 Cutting off

Claims (6)

[Claims] 1. An indoor unit of an air conditioner having a heat exchanger, a drain pan, and the like disposed inside a casing formed by fitting a plastic front panel and a base panel to each other, An indoor unit for an air conditioner, characterized in that one or both of the contact surfaces of the panel and the base panel are provided with means for reducing the contact area thereof. 2. The device according to claim 1, wherein said means is formed by cutting off a part of the contact surface of the front panel or the base panel and cutting most of the other part.
The indoor unit of the air conditioner as described. 3. The indoor unit of an air conditioner according to claim 1, wherein said means is constituted by providing a large number of minute projections on a contact surface of said front panel or base panel. 4. The indoor unit of an air conditioner according to claim 1, wherein said means reduces a contact area between said front panel and said base panel to 1/50 to 1/300. 5. A heat exchanger is provided inside a casing comprising a plastic front panel and a base panel, and a plastic drain pan is provided below the heat exchanger such that the front surface thereof is in contact with the front panel. In the indoor unit of the air conditioner arranged, a means for reducing a contact area between one or both of a front surface of the drain pan and a contact surface of the front panel which comes into contact with the drain pan is provided. Air conditioner indoor unit. 6. The air conditioner according to claim 5, wherein said means is provided by providing a large number of minute projections on a front surface of said drain pan or a contact surface of said front panel which contacts said drain pan. Indoor unit.