RU25177U1 - PULL OUT DROBE - Google Patents

Abstract

A fume hood, including a work table with a worktop and a working chamber placed on it, placed in a housing, moreover, an opening is made in the front wall of the working chamber, closed by a movable frame with a transparent insert, and inside the chamber there is a screen equipped with fasteners to the rear wall of the working chamber and installed with a gap relative to the countertop and top of the working chamber, characterized in that the working chamber and the countertop are rigidly interconnected, and the width of the countertop is greater than the depth of the working chamber, the upper part of the working the first chamber is made with a bevel from the side of its rear wall, the width of the opening made in the front wall of the working chamber is less than the width of this wall, while the upper and side edges of the opening are provided with visors connected to the metal case, and the rear wall of the working chamber is equipped with pockets designed for placement of screen mounting elements in them to the rear wall of the camera, the pockets being placed so that it is possible to change the gap between the screen and the tabletop and the gap between the screen and the top of the working chamber .

Description

PULL OUT DROBE

The utility model relates to ventilation technology, namely, devices designed to remove harmful substances directly from the place of their formation, and can be used when working with chemical reagents in laboratory conditions.

Fume hoods are known that are used as laboratory workstations (see, for example, USSR Av. No. 1759485, published September 7, 1992, Russian PM Certificate No. 19486, September 10, 2001, US patent No. 5318473, class. B08B 15/02, published on 06/07/1994).

The bottom of such cabinets is a desktop with a worktop, and the top is a working chamber with an exhaust pipe. An opening is made in the front wall of the working chamber, which is closed by a movable frame with a transparent element inserted in it, for example, glass.

IPC: V08V 15/02 allowing you to observe what is happening in the working chamber process. The exhaust pipe is connected to the ventilation system. Due to the rarefaction of air created by the fan, harmful substances formed in the working chamber are removed through the exhaust pipe without entering the laboratory premises. These fume hoods are characterized by the presence in their design of a large number of metal elements (metal working chamber, metal fasteners, etc.), which causes their significant drawbacks, namely: -limited scope. Such cabinets can only be used for working with chemicals that are neutral with respect to the metal used in the construction of these cabinets. - the fragility of the design. Over time, metal structural elements corrode, the mechanical functions of these elements are violated. Fume hoods are also known in which the working chamber is made of glass, see the prospectus of the American company LABCONCO Protector Class Mate Hoods, 2000 (A copy of the analogue is attached).

solely for illustrative purposes, for example, to demonstrate chemical onytes in educational laboratories.

The closest technical essence to the claimed one is a fume hood, including a work table with a worktop and a working chamber placed on it, placed in a housing, moreover, an opening is made in the front wall of the working chamber, closed by a movable frame with a transparent insert, and a screen is located inside the camera, equipped with fasteners to the rear wall of the cooking chamber, see prospectus of the Spanish company Flores Valles Fume Cupboards, Mod. 521. (A copy of the prototype is attached).

In this technical solution, the countertop of the desktop and the working chamber of the fume hood are made of plastic, neutral with respect to the action of an aggressive working environment, i.e. those harmful substances for which the device is intended to work. In comparison with the described analogues, such a fume hood has a significantly higher durability.

However, the prototype has significant disadvantages:

1) Elements for attaching the screen to the rear wall of the working chamber, with which the screen forms an exhaust channel, are made of metal in the prototype. the technical solution is less than the depth of the working chamber. In this regard, for the convenience of the laboratory assistant, the countertop is additionally equipped with a painted metal visor. Since the latter is in the working area, harmful things and things will inevitably fall on him. These circumstances determine the manifestation in the prototype of the above-described disadvantages inherent in known fume hoods, containing metal structural elements, and, ultimately, reducing the durability of the cabinet structure. The fragility of the prototype design is also due to the fact that the countertop and the working chamber are not connected into a single whole; they are only fastened with a sealant, which, like metal elements, will collapse over time under the influence of harmful things; 2) In the considered technical solution, the aperture in the front wall of the working chamber is made in the entire width of the working chamber. In this regard, there is a gap between the working chamber and the metal casing, as well as the fastening elements of the frame with glass. Hazardous substances from the working chamber inevitably fall into this gap, thereby reducing the efficiency of the fume hood and polluting the laboratory room. Another disadvantage of the low efficiency of the known device is that the screen in the prototype

permanently fixed (hung on metal bolts and nuts) on the rear wall of the working chamber, with gaps fixed relative to the table top and top of the working chamber. This does not allow to optimize the operating conditions of the fume hood taking into account the degree of volatility of the removed harmful substances, since for efficient operation of the fume hood, the values of the indicated gaps should change with a change in the degree of volatility of harmful substances.

This utility model is aimed at solving the problem of eliminating the possibility of destruction of the design of the fume hood under the influence of an aggressive working environment, as well as optimizing the conditions of its operation.

To solve this problem, in a fume hood including a work table with a worktop and a working chamber placed on it, placed in a housing, moreover, an opening is made in the front wall of the working chamber, closed by a movable frame with a transparent insert, and a screen equipped with fastening elements is located inside the chamber to the back wall of the working chamber and installed with a gap relative to the countertop and the top of the working chamber, the working chamber and the countertop are rigidly interconnected, moreover, the width of the countertop is greater than the depth of the working chamber, upper I part of the working chamber is beveled from the side of its rear wall, the width of the opening made in the front wall of the working chamber is less than the width of this wall, while

the upper and lateral edges of the opening are provided with visors associated with the metal case, and the rear wall of the working chamber is equipped with pockets designed to accommodate screen mounting elements to the rear wall, and the pockets are placed so that it is possible to change the gap between the screen and the tabletop and the gap between the screen and the top of the working chamber.

The applicant has not identified any technical solutions that have the same set of features as the claimed solution. This, according to the applicant, allows us to conclude that the claimed object meets the criterion of "novelty.

The proposed utility model is illustrated by drawings, which depict:

figure 1 is a General view of the device in a perspective view,

figure 2 - placement of the working chamber in the housing,

in Fig.Z - mounting the screen to the back of the camera

figure 4 is a rear view of the working chamber.

The fume hood contains a table 1 with a countertop 2, on which a working chamber 3 is installed, placed in a metal casing 4. At the same time, the countertop 2 and chamber 3 are made of plastic and are rigidly connected, in this example glued together, forming a single whole. The width of the countertop 2 is greater than the depth of the chamber 3, due to which the leading edge

tabletops protrudes forward relative to the front wall (not indicated by a separate position) of chamber 3, which is necessary for the convenience of the laboratory assistant. An opening is made in the front wall of the chamber 3 (not indicated by a separate position), closed by a frame 5 with tempered glass (not indicated by a separate position), mounted for movement along plastic guides 6. The opening width is less than the width of the front wall of the chamber 3, and the opening itself equipped with upper and side visors 7, rigidly fastened through plastic guides 6 with the housing 4, which prevents the ingress of harmful substances from the working chamber 3 into the metal housing 4 and protects the latter from destruction. A screen 9 is fixed on the rear wall 8 of the chamber 3. To accommodate the fasteners and install the screen 9 on the wall 8, pockets 10 are made. At the top of the working chamber, a protective bar 11 is fixed, made of the same material as the screen 9. Between the screen 9 , a strip 11 and a rear wall 8 of the chamber 3 are formed exhaust channel (a separate position is not indicated), associated with the exhaust pipe 12, combined with the working chamber 3 and connected to the ventilation system (not shown). In this case, the upper part of the chamber 3, on which the protective strip 11 is mounted, has a bevel 13 from the side of the rear wall 8. This form of the working chamber 3 makes it easy to fasten the strip 11 with plastic elements

fastenings without using metal ones. Sink 14 and faucet 15 are designed to flush reagents.

Thus, all the structural elements of the working chamber 3, including the exhaust pipe 12 and the fastening elements of the screen 9 and the protective strip 11 to the rear wall 8 of the chamber 3, are made of plastic, which is selected taking into account its resistance in a particular aggressive working environment.

The proposed fume hood operates as follows.

Depending on the degree of volatility of the harmful substances that you have to work with, screen 9 is installed in one of three possible positions that allow you to optimize the operating conditions of the device depending on the specified parameter of harmful substances.

In this case, the upper position of the screen 9, in which the gap between the countertop 2 and the screen 9 is maximum, and between the top of the working chamber 3, i.e. the strap 11 and the screen 9 is minimal, it is used when working with heavy harmful substances that are concentrated at the bottom of the working chamber 3. Accordingly, when working with light harmful harmful substances concentrating in the upper part of the camera 3, the screen 9 is set to the lower position, in which the gap between the top of the camera 3 and screen 9 is maximum, and between countertop 2 and screen 9 is minimal. When working with harmful substances that are a mixture

substances with varying degrees of volatility (heavy and light) screen 9 is installed in the middle position. In this particular example, in FIG. 1, the screen 8 is set to the upper position, in FIG. 2 and FIG. 3, in the middle position.

Through a raised frame 5 with glass, harmful substances, for example chemical reagents, are placed on the countertop 2 of the working table 1. By connecting the exhaust pipe 12 to the ventilation system in the working chamber 3, an air discharge is created, as a result of which the harmful substances enter the exhaust duct formed by the back the wall 8 of the chamber 3, the screen 9 and the protective strip 11, from where they are removed through the exhaust pipe 12. In this case, the visors 7 of the opening made in the front wall of the chamber 3 and the guides 6 reliably protect the metal casing 4 from penetration of harmful substances into it. The remaining reagents are washed into the sink 14 with water supplied from the faucet 15.

Thus, in the proposed utility model, unlike the prototype, the possibility of destruction of the structural elements of the exhaust hood under the influence of an aggressive working environment is excluded. the structural elements of the working chamber are made of plastic, selected taking into account its durability in a specific aggressive working environment, and the metal parts of the housing are protected from the penetration of harmful substances into it.

In addition, the proposed technical solution allows you to create optimal operating conditions for the fume hood taking into account the degree of volatility of the harmful substances to be removed; by removing them by changing the position of the screen relative to the table top and top of the working chamber.

These new properties of the claimed object provide increased durability and efficiency of the fume hood.

The proposed utility model can be implemented using conventional, widely known materials and devices, which, according to the applicant, indicates the compliance of the claimed object with the criterion of "industrial applicability.

Claims (1)

A fume hood including a work table with a worktop and a working chamber placed on it, placed in the housing, moreover, an opening is made in the front wall of the working chamber, closed by a movable frame with a transparent insert, and inside the chamber there is a screen equipped with fasteners to the rear wall of the working chamber and installed with a gap relative to the countertop and top of the working chamber, characterized in that the working chamber and countertop are rigidly interconnected, and the width of the countertop is greater than the depth of the working chamber, the upper part of the working the first chamber is made with a bevel from the side of its rear wall, the width of the opening made in the front wall of the working chamber is less than the width of this wall, while the upper and side edges of the opening are provided with visors connected to the metal case, and the rear wall of the working chamber is equipped with pockets designed for placement of screen mounting elements in them to the rear wall of the chamber, the pockets being placed so that it is possible to change the gap between the screen and the tabletop and the gap between the screen and the top of the working chamber .