Exhaust device having deflection plates

Abstract

An exhaust device having deflection plates comprises a cabinet that is provided with a space therein. An opening is formed in front of the cabinet. The air-extraction hood located at the top of the cabinet is provided at the bottom thereof with an elongate air-extraction slot facing downwards and parallel to the rear plate. A left deflection plate is vertically located in the space in a manner of being relatively oblique to the left lateral plate while a right deflection plate is vertically located in the space in a manner of being relatively oblique to the right lateral plate. Thereby, the air drawn towards the elongate air-extraction slot can flow into the cabinet via the left and the right deflection plates so as to prevent the leakage of pollutants from the opening in front of the cabinet.

Description

TECHNICAL FIELD[0001]The present invention relates to an exhaust device having deflection plates, and more particularly, to an exhaust device that has deflection plates used for guiding the airflow in the cabinet so as to prevent the leakage of pollutants and is suitable for the cabinets in factories and laboratories and the exhaust cabinets in commercial kitchens.BACKGROUND[0002]For performing the function of a conventional exhaust cabinet, a shelter plate with an opening is provided on the upper end of a cabinet, and a flow-guide plate is vertically placed in the rear of the cabinet, where the flow-guide plate is provided with a specially designed opening. Through the opening of the shelter plate and the opening of the flow-guide plate in the rear of the cabinet, harmful gas can be drawn out by using an air-extraction machine and ducts. When the exhaust cabinet is used, the air-extraction machine should be operated correspondingly in order to continue air extraction. During this m...

AI Technical Summary

Benefits of technology

[0006]An object of the present invention is to provide an exhaust device having deflection plates, where an elongate air-extraction slot is provided on the bottom of the air-extraction hood, and a left and a right deflection plates are provided in the space beneath the cabinet so as to exhaust high-temperature pollutants or soot effectively and prevent the leakage of the pollutants or soot.

[0007]Another object of the present invention is to provide an exhaust device having deflection plates, where an elongate air blow part is provided in front of the bottom plate of the cabinet, and a left and right deflection plates are respectively provided in air-supply spaces located at the left and right sides of the elongate air blow slot, so as to confine the airflow inside the cabinet and prevent the leakage of pollutants.

[0008]Another object of the present invention is to provide an exhaust device having deflection plates, where a guiding plate is respectively provided at the front ends of the left and right lateral plates, and a guiding part is provided on the bottom of the front plate, so as to let airflow smoothly flow into the cabinet and reduce the size of the backflow area in order to decrease the possibility of pollutants' leakage.

[0009]In order to achieve above objects, the present invention provides an exhaust device having deflection plates, comprising a cabinet, a left deflection plate, and a right deflection plate. The cabinet includes an air-extraction hood, a bottom plate, a left lateral plate, a right lateral plate, and a rear plate, all of which define a space. An opening is provided in front of the cabinet. An air-extraction part is provided at the bottom of the air-extraction hood. The air-extraction part has an elongate air-extraction slot facing downwards and the elongate air-extraction slot is parallel to the rear plate. The air-extraction part is connected with an air-extraction machine for drawing air upwards. The left deflection plate is vertically located in the space in a manner of being relatively oblique to the left lateral plate, so as to form a first included angle between the left deflection plate and the left lateral plate. The right deflection plate is symmetrical to the left deflection plate and is vertically located in the space in a manner of being relatively oblique to the right lateral plate, so as to form a second included angle between the right deflection plate and the right lateral plate. Thereby, it is able to guide the airflow in the cabinet and prevent its leakage.

Problems solved by technology

However, when the door of the conventional exhaust cabinet is open, based on the principles of Aerodynamics, harmful gas within the cabinet may escape easily around the peripheries of the door.

Moreover, the leakage may be even severer when operators are opening or closing the door, or stand in front of the open cabinet for experimental operations, or when there are ambient drafts or there are people walking by.

The main reason of the leakage is that vortex and turbulence are easily formed around the peripheries of the cabinet door and around operators' chests.

The vortex and turbulence may result in the mass and momentum exchange between the inside and the outside of the cabinet.

Therefore, the leakage of the pollutants in the cabinet is scarcely avoidable.

Unfortunately, there is nearly no conventional exhaust cabinet can be used without opening and closing its door.

Besides, the exhaust cabinet is scarcely placed in the environment where there is no ambient air turbulence or there are no people walking by.

As a result, in the laboratories, factories, or buildings using the conventional exhaust cabinets, people usually smell the sour odor emitted from chemicals because pollutants continue leaking from the cabinets.

Operators and people working thereby may get used to the odor and long-term chemical pollution occurs.

However, because the left and the right lateral plates (e, e1) are completely enclosed ones, experimental results show that unsteady vortex will appear in the cabinet after the air flows in respectively through the gaps between the two ends of the air blow parts (b, b1) and the left and right lateral plates (e, e1).

Consequently, airflow will partially flow out through the two gaps so as to result in the leakage of harmful gas.

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