Motor shield for the drainage device of a cooling or air-conditioning system

A motor shield covered on a motor of a drainage device over a cooling vane is disclosed to include a shield body having an arched portion and a straight portion, a guide wall disposed in the shield body and having an arched segment and a straight segment connected to the straight portion of the shield body, an airflow zone defined in the shield body in an interference relationship relative to the cooling vane and surrounded by the arched segment and straight segment of the guide wall and the arched portion and straight portion of the shield body, horizontally extending air outlets and vertically extending air outlets respectively located on the arched portion and straight portion of the shield body, and air inlets located on the periphery of the shield body. During rotation of the cooling vane, a flow of air is induced to carry heat out of the shield body through the vertically and horizontally extending air outlets efficiently.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to drainage device technology and more particularly, to a motor shield for the drainage device of a cooling or air-conditioning system, which provides an airflow guiding function.

2. Description of the Related Art

A drainage device for use in a cooling or air-conditioning system generally uses a motor to provide a dynamic force for drainage of water. However, a motor releases waste heat during operation. Therefore, a drainage device of this type must have a heat dissipation device to assure normal working of the product.

Taiwan Utility Model M308567, issued to the present inventor, discloses a heat dissipation technique entitled “Motor shield with hot airflow guiding function to dissipate heat”. According to this design, an arched guide board is arranged on the surface of the top side of the motor shield for shunting discharged gas so that a part of the discharged gas, subject to the guidance of the arched guide board, is kept flowing within a predetermined distance without scattering, enhancing the stability of the eddy flow of the discharged gas.

However, the aforesaid prior art technique is adapted for guiding the discharged gas that flows out of the motor shield but not for guiding the flow of gas inside the motor shield. According to this design, the heat dissipation effect produced subject to the airflow guiding functioning of the arched guide board is limited.

U.S. Pat. No. 7,252,482, entitled “Motor driven pump with improved motor cooling air flow”, discloses an electric motor-driven pump adapted for pumping condensate from refrigeration and air conditioning systems in which a motor cover mounted on a reservoir cover defines a vertically extending cooling air inlet and horizontally extending discharge ports for the flow of cooling air propelled by a fan. This design does not provide a significant airflow guiding function. The horizontally extending discharge ports simply facilitate outward dispersion of cooling air propelled by the fan. This arrangement does not significantly enhance heat dissipation.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a motor shield for the drainage device of a cooling or air-conditioning system, which greatly enhances heat dissipation.

To achieve this and other objects of the present invention, a motor shield is installed in a drainage device of a cooling/air-conditioning system and covered on a motor of the drainage device over a cooling vane at the motor. The motor shield comprises a shield body defining a chamber for accommodating the cooling vane of the motor and having a top wall thereof divided into an arched portion and a straight portion, a guide wall disposed in the top side in the shield body within the chamber and having an arched segment and a straight segment connected to the straight segment of the guide wall, an airflow zone defined in the chamber inside the shield body in an interference relationship relative to the cooling vane of the motor and surrounded by the arched segment and straight segment of the guide wall and the arched portion and straight portion of the top wall of the shield body, a plurality of horizontally extending air outlets located on the arched portion of the top wall of the shield body, a plurality of vertically extending air outlets located on the straight portion of the top wall of the shield body, and at least one air inlet located on the periphery of the shield body. Thus, when the cooling vane is rotated, a flow of air is induced to carry heat out of the shield body through the vertically and horizontally extending air outlets efficiently.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1˜7, a motor shield10in accordance with a first embodiment of the present invention is shown installed in a drainage device90of a cooling (refrigeration) or air-conditioning system and covered on a motor91.FIGS. 1˜3illustrate the structure of the motor shield10.FIGS. 4˜7illustrate the motor shield10jointed to the drainage device90.

The motor shield10comprises a shield body11defining therein a chamber12. After covering of the shield body11on the drainage device90, the chamber12is adapted for accommodating a motor91having a cooling vane92. A guide wall14is located on the inside of the shield body11at the top. The guide wall14has an arched segment141and a straight segment142. The shield body11has its top wall divided into an arched portion111and a straight portion112. An airflow zone16is defined in the shield body11and surrounded by the arched segment141and straight segment142of the guide wall14and the arched portion111and straight portion112of the top wall of the shield body11. The straight portion112of the top wall of the shield body11and the straight segment142of the guide wall14are connected together. The arched portion111of the top wall of the shield body11defines a plurality of horizontally extending air outlets17. The straight portion112of the top wall of the shield body11defines a plurality of vertically extending air outlets18. Further, the cooling vane92is set in interference with the airflow zone16. The shield body11further has at least one air inlet19defined in the peripheral wall thereof. According to this embodiment, the shield body11has two openings19′ respectively located on the bottom edge of the shield body11at two opposite sides. After the shield body11is covered on the drainage device90, the two openings19′ form two air inlets19in the bottom edge of the peripheral wall of the shield body11at two opposite sides.

According to this embodiment, the vertically extending air outlets18are axially set in a tangential manner relative to the cooling vane92. Further, the guide wall14is a plate member formed integral with the shield body11. Further, the shield body11has a plurality of reinforcing ribs171that are spaced corresponding to the horizontally extending air outlets17to reinforce the structural strength of the shield body11.

The operation of the motor shield10will be described hereinafter.

Referring toFIG. 6andFIG. 7, during operation of the motor91, hot air rises and enters the airflow zone16. At the same time, the cooling vane92is being rotated by the motor91(in the direction as indicated by the arrowhead sign at the cooling vane) to cause flowing of air in the airflow zone16along the border area of the airflow zone16subject to the arrangement of the cooling vane92in interference with the airflow zone16.

During rotation of the cooling vane92to cause flowing of air in the airflow zone16along the border area of the airflow zone16, the induced airflow will disperse outwards when reaches the horizontally extending air outlets17. When the induced airflow reaches the guide wall14, it will flows along the arched segment141toward the straight segment142and will then be stopped by the straight segment142and forced to change its flowing direction toward the outside through the vertically extending air outlets18. Because the vertically extending air outlets18are axially set in a tangential manner relative to the cooling vane92, the induced airflow can be guided out of the vertically extending air outlets18smoothly without interference. Subject to reduced air pressure in the shield body11at this time, outside cooling air is guided into the chamber12through the air inlets19.

As stated above, the motor shield in accordance with the first embodiment of the present invention enables hot air to be forced to flow toward the outside and then to disperse, enhancing dissipation of heat.

FIG. 8illustrates a motor shield20in accordance with a second embodiment of the present invention. This second embodiment is substantially similar to the aforesaid first embodiment with the exception that the vertically extending air outlets28are axially arranged in the shield body21in a radial relationship.

Thus, when the airflow induced in the airflow zone26is forced by the guide wall24to flow toward the vertically extending air outlets28, the radial arrangement of the vertically extending air outlets28facilitates dispersion of the airflow into the outside open space, enhancing heat dissipation efficiency.

The other structural details, operation and effects of this second embodiment are same as the aforesaid first embodiment, and therefore no further detailed description in this regard is necessary.

FIG. 9illustrates a motor shield30in accordance with a third embodiment of the present invention. This third embodiment is substantially similar to the aforesaid first embodiment with the exception that the vertically extending air outlets38are axially arranged in the shield body31in a parallel relationship.

Thus, when the airflow induced in the airflow zone36is forced by the guide wall34to flow toward the vertically extending air outlets38, the parallel arrangement of the vertically extending air outlets38cuts the airflow into multiple currents that flow out of the motor shield30in a parallel manner without interfering with one another, enhancing heat dissipation efficiency.

The other structural details, operation and effects of this third embodiment are same as the aforesaid first embodiment, and therefore no further detailed description in this regard is necessary.

In conclusion, the design of the arched segment141and straight segment142of the guide wall14and the design of the arched portion111and straight portion112of the top wall of the shield body11facilitate expelling of the induced airflow, enhancing heat dissipation efficiency.