IE852836L

IE852836L - Air duct

Info

Publication number: IE852836L
Application number: IE852836A
Authority: IE
Original assignee: Gebroeders Rock Beheer B V
Priority date: 1984-11-14
Filing date: 1985-11-13
Publication date: 1986-05-14
Also published as: DE3567092D1; DK161040C; EP0183308B1; IE57254B1; EP0183308A1; ATE39568T1; DK520585D0; DK520585A; NL8403473A; DK161040B

Abstract

Air duct formed by a plate-shaped element provided with passages, having a curved course in cross-section and a corrugated course in longitudinal section, whereby rectangular slotted holes have been provided only in the tops of the corrugations in those portions of the plate-shaped element which join the boundary edges of said plate-shaped element that rest on the floor.

Description

This invention relates to a plate-shaped element provided with 20 holes for the passage of air having a curved course in cross-section, thus forming two edges, and a corrugated course in longitudinal section, the element being intended to rest with its edges on the floor of a building so as to form an air duct.

Such elements, usually placed on the floor in a storage room, in such a manner that several such ducts, which can be built up from sections, are thereby arranged at some distance of and parallel to each other. Products to be dried, cooled and/or ventilated can then be brought into the storage room such, that said products are deposited in 30 a heap above and between the air ducts. For drying, cooling and/or ventilating the products air can be supplied to the air ducts continuously or intermittently, which air, whether or not heated, can escape from the air duct via the passages in the plate-shaped element and stream along the products to be treated.

For the use of such elements for drying grains the elements are usually provided with small perforations over their entire surface, (see e.g. US-A-3,054,342). For bigger tuberous or bulbous crops, such as e.g. potatoes, onions and the like such air ducts proved to be unsatisfactory. In connection with this it has been proposed to provide those portions of the plate-shaped elements, which join the boundary edges of the plate-shaped elements, which rest on the floor, 5 with regularly spaced holes with a circular section. Also with such an arrangement, however, no satisfactory results were achieved.

Now according to the invention the plate-shaped element is characterized in that the holes are slotted holes, which are provided 10 only in the tops of corrugations in those portions of the plate-shaped element which join the edges of said plate-shaped element.

Surprisingly it has appeared that the use of such a construction effects a considerably improved operation with regard to drying, 15 cooling and/or ventilating in comparison with the constructions described hereinabove, whilst in addition, because of the provision of holes only in the tops of the corrugations, a robust construction of the plate-shaped element is maintained, so that said plate-shaped element can take comparatively great loads, caused by products lying on 20 the plate-shaped element.

The invention will be further explained hereinafter with reference to embodiments of the construction according to the invention diagrammatically illustrated in the accompanying Figures.

Figure 1 is a diagrammatic perspective view of a few adjacently arranged air ducts; Figure 2 is a diagrammatic view of the end of an air duct; Figure 3 is a top view of a plate-shaped element intended for forming an air duct according to the invention; Figure 4 is a side view of Figure 3, and Figure 5 is a top view of a second embodiment of a plate-shaped element suited for forming an air duct according to the invention.

Figure 1 illustrates a few air ducts 2 located adjacent to each other on a bottom 1, which ducts have been arranged parallel to each other. As will be apparent from Figures 1 and 2 the air ducts have, in cross section, curved, usually semicircular shape, whilst seen in 5 longitudinal section an air duct has a corrugated course. Usually the ducts are thereby made of metal sheet, but of course it will be conceivable to use other materials for this purpose, such as e.g. plastic material. An air duct can be made of a single plate-shaped part, but in particular with longer air ducts a duct will usually be 10 built up from sections which overlap each other at their ends. Such an air duct or a section of an air duct can be formed by bending a corrugated sheet 3 as illustrated in Figures 3 and 4 around its longitudinal axis extending parallel to its boundary edges 4 and 5. As further appears from Figure 3 slotted holes 7 have been provided in the 15 tops 6 of the corrugations in the portions of the corrugated sheet joining the boundary edges 4 and 5 in such a manner that the longitudinal axes of said slotted holes coincide with the longitudinal axes of the corrugations and are therefore perpendicular to the boundary edges 4 and 5. In the bottoms 8 of the corrugations no holes 20 have been provided, as will be apparent from Figures 3 and 4.

As will further appear from Figure 3 the slotted holes 7 located nearest to the boundary edges 4 and 5 lie in a line in the corrugation tops 6 located adjacent to each other, whilst the slotted holes located 25 further away from the boundary edges 4 and 5 in a pair of adjacent corrugation tops 6, seen in the longitudinal direction of the boundary edges 4 and 5, are staggered relatively to each other. As a result of this a better spreading of the air coming out of the air duct via the slotted holes is achieved as well as a better resistance of the air 30 duct to collapsing.

In practice it has appeared that thereby efficient ventilation, drying, cooling or the like can be achieved when five slotted holes are provided in every corrugation top, whereby the length of such a slotted 35 hole is preferably 55 mm and the width 20 mm. With an air speed of 6 to 7 m per second the occurrence of turbulence when the air streams out of the slotted holes appears to be prevented, as a result of which an equal stream of the air through the material to be treated will be achieved.

With a diameter between +1200 mm and 1600 mm of the corrugated sheet bent into a semicircle around its longitudinal axis the centre 5 distance between a pair of rectangular slotted holes located in a corrugation top 6 will preferably be +130 mm, except for those slotted holes which have been arranged comparatively, closely together near the secondary edges 4 and 5 as is illustrated in the Figures and whereby the centre distance between said slotted holes is 65 mm.

Figure 5 shows a development of a plate-shaped portion, which can be used for making air ducts with smaller diameters e.g. between +630 mm and 1025 mm. As is illustrated in this Figure the centre distance between the slotted holes, which for the rest have the same length as in the first mentioned embodiment, has thereby been chosen smaller and is preferably 90 mm here. The centre distance between the slotted holes arranged closely together near the boundary lines 4 and 5 has thereby been kept equal to that of the embodiment discussed first. t The width of the strip of the sheet joining a boundary edge 4 or 5 measured in the direction of the corrugations is preferably less than 1/20 of the width of the developed sheet illustrated in Figures 3 and 5 measured between the boundary edges 4 and 5.

Claims

CLAIMS - 6 -

1. A plate-shaped element provided with holes for the passage of air having a curved course in cross-section, thus forming two edges, and a 5 corrugated course in longitudinal section, the element being intended to rest with its edges on the floor of a building so as to form an air duct, wherein the holes are slotted holes which are provided only in the tops of the corrugations in those portions of the plate-shaped element which join the edges of the said plate-shaped element. 10

2. The element as claimed in claim 1, wherein, seen in the longitudinal direction of the air duct, the slotted holes in successive corrugation tops are staggered relatively to each other. 15

3. The element as claimed in claim 1 or 2, wherein, seen in the longitudinal direction of the air duct, the slotted holes provided in the corrugation tops and located nearest the edges, lie in a line. \

4. The element as claimed in any of the preceding claims, wherein the 20 slotted holes have been provided in such a manner that the longitudinal axes of the slotted holes coincide with the longitudinal axes of the corrugation tops.

5. The element as claimed in any of the preceding claims, wherein the 25 length of a slotted hole is +50 mm and width is ± 20 mm.

6. The element as claimed in any of the preceding claims, wherein the width of the strip, joining the edge of an air duct, in which the slotted holes have been provided, measured in the longitudinal 30 direction of a corrugated top, is not more than 1/20 of the entire length of said corrugation top.

7. An air duct element substantially as described herein with reference to and as shown in the drawings. 35 Dated this 13th day of November, 1985. BY: fOMfctMS & CO., AftjjTjpants' Agents, (Signed) V o&r- 5, Dartmouth Road, DUBLIN 6.