Preheating oven, particularly for panels to be molded

Abstract

 A preheating oven (1), particularly for panels (20) to be molded, comprising, inside a preheating chamber (2), two mutually spaced wingfitted conveyors (3,4). The wings (10) of the two conveyors (3,4) engage the opposite edges of panels (20) being preheated in order to support them at a substantially horizontal plane of arrangement and convey in succession the panels (20) being treated from an inlet region (30) to an outlet region (31).

Description

[0001] The present invention relates to a preheating oven, particularly for panels to be molded.

[0002] As it is commonly known, during operations for molding extruded panels made of plastics preheating ovens are used which are meant to raise the heat level of the panels to be subsequently processed.

[0003] Conventional ovens are constituted by a chamber inside which a star conveyor is provided which is formed in practice by a plurality of wings which protrude from a central shaft and define a plurality of compartments wherein the panels being processed are inserted.

[0004] The panels are inserted radially with respect to the star conveyor and are gradually turned through a 180° angle to reach the opposite position, where they are extracted, after the preset period of permanence inside the preheating chamber.

[0005] With this embodiment, the panels in practice rest edgeways on the conveyor and are turned over from the entry position to the exit position.

[0006] The edgeways resting of the panels can cause deformations of said panels; moreover, the particular structure of the conveyor, with radially arranged wings, does not allow a good distribution of the hot air in the preheating chamber, with consequent heat gradients among the different points of the panel.

[0007] Moreover, the insertion of the panel in a radial direction with respect to the conveyor is not easy, since it is necessary to precisely adjust insertion in order to avoid undesirable impacts which might damage the panel.

[0008] The aim of the present invention is to eliminate the above-described drawbacks, by providing a preheating oven particularly for panels to be molded, which allows to keep the panel on a horizontal plane of arrangement, thus avoiding the possibility of deformations of the edges of said panel.

[0009] Within the scope of this aim, a particular object of the present invention is to provide a preheating oven in which it is possible to achieve uniform distribution of the hot air inside the preheating chamber, thereby achieving uniform preheating of the entire panel.

[0010] A further object of the present invention is to provide a preheating oven in which all of the operations for inserting and removing the panel are facilitated, said panel encountering no obstacles of any kind both during insertion and during extraction.

[0011] A still further object of the present invention is to provide a preheating oven which, thanks to its particular constructive characteristics, is capable of giving the greatest assurances of reliability and safety in use.

[0012] This aim, these objects and others which will become apparent hereinafter are achieved by a preheating oven particularly for panels to be molded, according to the present invention, characterized in that it comprises, inside a preheating chamber, two mutually spaced wing-fitted conveyors, the wings of said conveyors engaging the opposite edges of panels being preheated in order to support them with a substantially horizontal plane of arrangement and convey in succession the panels being treated from an inlet region to an outlet region.

[0013] Further characteristics and advantages will become apparent from the following detailed description of a preferred but not exclusive embodiment of a preheating oven particularly for panels to be molded, illustrated only by way of non-limitative example in the accompanying drawings, wherein:

Figure 1 is a schematic perspective view of the two wing-fitted conveyors, according to the present invention;

Figure 2 is a schematic sectional view, taken along a vertical plane, of the preheating oven.

[0014] With reference to the above figures, the preheating oven particularly for panels to be molded, generally designated by the reference numeral 1, comprises a preheating chamber 2 inside which a first wing-fitted conveyor 3 and a second wing-fitted conveyor 4 are provided which are formed by means of a belt 5 which runs continuously around a lower roller 6 and an upper roller 7; wings 10 protrude substantially at right angles from the belt 5 and delimit compartments between them.

[0015] The conveyors 3 and 4 form rising portions which face each other so that the corresponding wings 10 are directed toward each other and form the support for the panels 20, which are retained at their opposite edges and remain on a substantially horizontal plane of arrangement.

[0016] In the preheating chamber there is provided an inlet region 30, where the panels 20 to be treated are inserted, which is located in a downward region; there is also provided an outlet region 31 which is located in an upward region, at a higher level than the inlet region 30, and from which the preheated panels are removed.

[0017] With the above-described arrangement it is therefore possible to have available an oven which allows to store a large number of panels which are subjected to the preheating treatment for the intended time.

[0018] The panels remain strictly on a horizontal plane of arrangement since they are supported at mutually opposite edges and the operations for inserting and removing the panels from the oven are also considerably facilitated.

[0019] It should be added, that it is possible to provide means for varying the distance between the wing-fitted conveyors, so as to adapt to panels having different dimensions.

[0020] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the inventive concept.

[0021] All the details may also be replaced with other technically equivalent elements.

[0022] In practice, the materials employed, as well as the contingent shapes and dimensions, may be any according to requirements.

[0023] The disclosures in Italian Patent Application No. MI98A001731 from which this application claims priority are incorporated herein by reference.

[0024] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A preheating oven, particularly for panels to be molded, characterized in that it comprises, inside a preheating chamber (2), two mutually spaced wing-fitted conveyors (3,4), the wings (10) of said two conveyors (3,4) engaging the opposite edges of panels (20) being preheated in order to support them at a substantially horizontal plane of arrangement and convey in succession the panels (20) being treated from an inlet region (30) to an outlet region (31).

2. The preheating oven according to claim 1, characterized in that each one of said wing-fitted conveyors (3,4) comprises a continuous belt (5).

3. The preheating oven according to the preceding claims, characterized in that said wings (10) protrude substantially at right angles from said belt (5) and said conveyors (3,4) have mutually opposite rising portions.

4. The preheating oven according to one or more of the preceding claims, characterized in that said inlet region (30) is arranged at a lower level than said outlet region (31).

5. The preheating oven according to one or more of the preceding claims, characterized in that said panels (20) are inserted in said preheating oven (2) in a direction which is substantially parallel to the axis of the supporting rollers (6,7) of said wing-fitted conveyors (3,4).

6. The preheating oven according to one or more of the preceding claims, characterized in that it comprises means for varying the mutual distance between said wing-fitted conveyors (3,4) if the dimensions of the panels (20) vary.

Drawing