EXTRACTION DEVICE

Abstract

The utility model relates to the field of eliminating and purifying polluted air in a work area and can be used, in particular, during manicure / pedicure work, polishing products, and other work involving the generation of fine particles in the air. The technical result consists of increasing the efficiency of an exhaust device. The exhaust device consists of a housing, the upper part of which contains a work surface with an inlet, an air intake grille, and a filter element, while the other part contains a fan and an outlet. The air intake grille has a dome-shaped shape, and the cell area and thickness of the grille decrease from the base to the top. 1 c.p. f-ly, 3 ill.

Description

[0001] Technical field

[0002] The utility model relates to the field of eliminating and purifying polluted air in the work area and can find its application, in particular, during manicure / pedicure work, polishing of products and other work that involves the formation of fine particles in the air.

[0003] Technology Level

[0004] From the prior art (RU 206258 U1, 09 / 02 / 2021), an exhaust device is known, consisting of a housing, in the upper part of which are located: a horizontal working surface with an inlet opening, an air intake grille located on the said working surface, and a filter element, and in the other part of which a fan and an outlet opening are located.

[0005] A disadvantage of the known solution is that the air intake grille is aligned with the horizontal surface. This design results in an uneven distribution of air velocity across the filter surface, increasing localized clogging and reducing filter life due to a smaller area being utilized. Furthermore, grille cells with a fixed opening area, located in the same plane, do not ensure uniform flow of filtered air to the fan air intake. Uneven velocity increases resistance due to air spreading across the filter surface, further reducing the efficiency of this device.

[0006] Also known from document US 20250072578 A1, 06.03.2025, is an exhaust device consisting of a housing, the upper portion of which contains a work surface with an inlet, an air intake grille, and a filter element. The other portion contains a fan and an outlet. In this known solution, the air intake grille has a variable curvature and a variable aperture area. However, the change in the area of ​​these apertures is directed from one end of the device to the other, while the dust generated during operation is uniformly distributed over the surface of the device. This results in the same drawback of localized filter clogging and reduced efficiency.

[0007] The proposed utility model is aimed at overcoming the shortcomings of the state of the art and, when implemented, allows for the achievement of a technical result consisting in increasing the efficiency of the exhaust device.

[0008] Disclosure of Utility Model

[0009] To achieve the specified technical result, an exhaust device is proposed, consisting of a housing, in the upper part of which a working surface with an inlet opening, an air intake grille and a filter element are located, and in the other part of which a fan and an outlet opening are located, characterized in that the air intake grille has a dome-shaped form, and the area of ​​the cells and the thickness of the grille decrease from the base to the top.

[0010] In a further embodiment, it is assumed that the cell walls are oriented towards the fan.

[0011] Implementation of a utility model

[0012] To clarify the essence of the utility model, the description is supplemented with references to non-excluding embodiments of the illustration, according to which the following is presented:

[0013] Fig. 1 - exhaust device, top view;

[0014] Fig. 2 - section of the exhaust device;

[0015] Fig. 3 - exhaust device, side view.

[0016] As shown in Fig. 2, the exhaust device consists of a housing, the upper portion of which contains a work surface with an inlet opening (1). The device is equipped with an air intake grille (2). The dome-shaped grille may be understood as the embodiment shown in Fig. 2, in which the grille walls form a truncated dome. The grille cells may have any shape, such as round, rectangular, trapezoidal, etc.

[0017] In a preferred embodiment, the exhaust device uses a replaceable flat filter element (not shown), which can be placed, for example, on a platform (3). The device can be conditionally divided into an upper and another (lower, main) part, the second of which provides a place for installing a fan (4). The fan can be a centrifugal fan, sucking air from the side of the inlet opening and directing the air flow to the outlet opening (5) located on the side of the device, according to Fig. 3. However, the utility model is not limited to this embodiment and assumes the possibility of using other types of fans (axial, diagonal, etc.) with the outlet opening located in a part of the housing corresponding to the effective direction of operation of the fan.

[0018] As is known, in installations with cellular filters of all types and with dry filters, uneven speeds cause an increase in resistance due to the spread of air over the filter surface (Guide to the design of air purification from dust in supply ventilation and air conditioning systems, Moscow, Stroyizdat, 1984, p. 18-[1]).

[0019] The advantage of the utility model is that the air intake grille is designed in such a way that it has a dome-shaped form, and the cell area and the thickness of the grille decrease from the base to the top.

[0020] In the proposed solution, the total effective cross-section decreases as it approaches the dome's apex, resulting in increased local resistance along the radial plane: small cells at the top create slightly higher specific resistance than large cells at the base. This results in some of the flow from the central zone being redistributed toward the periphery, leveling the velocity field above the flat filter installed on the platform. However, this resistance for small cells should not be too high, as this could lead to air stagnation and reduce the uniformity of the air velocity field. To address this issue, additional improvements have been made to the proposed device, as shown below.

[0021] In the proposed solution, the dome-shaped grille increases the effective inlet area (over the dome surface) with the same projection onto the work surface (e.g. table), so the average suction speed per unit area of ​​the grille can be lower with the same flow rate, which reduces localized areas of high air velocities.

[0022] At the same time, it is known that the hydraulic resistance in the grate depends on the ratio of the grate thickness to the diameter (i.e., to the area) of the hole 1 / d (G.I. Derbunovich et al., Hydraulic Resistance of Perforated Gratings, Scientific Notes of TsAGI, Vol. XV, No. 2, 1984 - [2]). Thus, with the same grate thickness, too much resistance may arise in holes with a smaller diameter, leading to flow turbulence, a decrease in throughput and, as a consequence, a violation of the uniformity of the velocity field and a decrease in the efficiency of the exhaust device.

[0023] In the proposed utility model, as the cell area decreases from base to top, the grate thickness is simultaneously reduced, meaning the channel length in smaller cells will be shorter than in larger cells. This reduces the resistance of the decreasing cells while maintaining flow uniformity and the efficiency of the exhaust device. The ratio of grate thickness to cell opening area can be determined based on empirical relationships known from [2].

[0024] The proposed solution involves further development, whereby the cell walls forming the channels are oriented toward the fan. This will reduce friction of dust particles against the channel walls and their accumulation in the cells, while maintaining the throughput, uniformity of the velocity field, and the efficiency of the exhaust device. Within the scope of the utility model, the orientation of the walls can be understood not only as their strict orientation toward the fan inlet channel but also as a design in which the channel walls are tilted away from the central axis of the cell. Thus, the exhaust device can be adapted to effectively operate with fans of different types, sizes, and locations within the device housing.

Claims

1. An exhaust device consisting of a housing, in the upper part of which a work surface with an inlet opening, an air intake grille and a filter element are located, and in the other part of which a fan and an outlet opening are located, characterized in that the air intake grille has a dome-shaped form, and the area of ​​the cells and the thickness of the grille decrease from the base to the top.

2. An exhaust device according to paragraph 1, characterized in that the cell walls are oriented towards the fan.

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