Oven

Abstract: An oven has a housing with heating means and a conveyor belt which runs through the housing, and on which the food products to be heated can be conveyed through the housing. The belt follows a first helical path and a second helical path connecting to the first path, in which second path the belt, viewed in the vertical direction, carries out a movement in the opposite direction to that in the first path.

Description: The invention relates to an oven with a housing which has heating means and a conveyor means which runs through the housing for food products to be heated, which conveyor means follows a first helical path and a second helical path which connects to the first path, in which second path the conveyor means, viewed in the vertical direction, carries out a movement in the opposite direction to that in the first path. Such an oven is known from FR-A-2471143. The conveyor means applied therein comprises a chain having two helical paths which are situated in a housing provided with heating means. The chain comprises a plurality of links, which each carry a mould for receiving a dough product. The products which are carried through the housing by the chain are exposed to one and the same uniform heating environment. Depending on the product to be heated, a specific heating temperature may be selected which is generally constant over the full area of the housing. The object of the invention is to provide a more versatile oven suitable for various products and in which the heating conditions are controllable in a more flexible way. This object is achieved by the characterising features of claim 1. Because the two chambers each have their own heating device, different conditions can be set, which is often very desirable for good treatment of the products. The invention will be explained in greater detail below with reference to an example of an embodiment shown in the figures. Figure 1 shows a longitudinal section of the oven. Figure 2 shows a top view. The oven shown in Figure 1 has a base frame 1 containing a tank 2 with legs 3. These legs are equipped in a known manner with a lifting device (not shown), by means of which the cap 4 resting on the tank 2 can be lifted, in order to gain access to the inside of the oven. The inside of the oven has two drums 5, 6. These drums have fixed supports 6, which are disposed helically along the outside of the drums, and on which the conveyor belt 7 rests. The drums 5, 6 can be driven by means of the synchronised drive motors 8, 9. In the embodiment shown, each drum drives four windings of the conveyor belt 7. The drums turn to the right, viewed from above, so that drum 5 drives the downward moving belt section, and drum 6 the upward moving section. At the outlet opening 13 the belt leaves the oven, while it enters the oven at inlet opening 14. The returning belt part 15 runs between these two openings, outside the oven. Extractors 16, 17 for extracting escaping vapours are placed above the belt, near the outlet opening 13 and the inlet opening 14. Hot-air heating devices, indicated in their entirety by 18, are provided in the top of the cap. They comprise a blower 19 with a volute housing. This housing opens out into channel 20, which has an outflow opening 21 in its bottom wall. Heating elements 23 are provided in the channel 20, in the direction of flow upstream of the outflow opening 21. These elements heat the air which has been fed in before it can flow out of outflow opening 21 down along the products on the helical paths of the conveyor belt. The air can subsequently be sucked in again through inlet opening 24, in such a way that a continuous circulation can be maintained. The oven is divided into two chambers 26, 27 by means of partition 25. The conveyor belt can move out of chamber 27 to chamber 26 by means of the passage 28 in the partition 25. Since both chambers 26, 27 have their own heating elements 23, different conditions can be selected in the chambers. In the embodiment shown, the helical paths have opposite pitch angles, and the drums turn in the same direction. However, according to a variant not shown, the helical paths can have the same pitch angle, while the drums turn in opposite directions. In this case the belt runs crosswise in the part of its path extending between the two drums.

Claims: Oven with a housing which has heating means (18, 19, 23) and a conveyor means (7) which runs through the housing for food products to be heated, which conveyor means (7) follows a first helical path and a second helical path which connects to the first path, in which second path the conveyor means, viewed in the vertical direction, carries out a movement in the opposite direction to that in the first path, wherein the housing comprises a tank (2) and a cap (4) resting on said tank (2), in that the conveyor means are constituted by one conveyor belt (7) on which the food products to be heated can be accommodated, in that at the level of the two helical paths the conveyor belt (7) is driven in each case by a rotatable drum (5, 6) with vertical axis of rotation, the first path being situated in a first chamber (26) in the housing, the second path being situated in a second chamber (27) in the housing, which chambers (26, 27) are separated by a partition (25) provided with an opening (28) through which the conveyor belt (7) is conveyed, the two chambers (26, 27) each having their own heating device (18), so that two different temperature zones are formed, said heating devices (18) each providing hot-air heating and being provided in the top of the cap (4). Oven according to Claim 1, in which the pitch angles of the two paths have an opposing sign. Oven according to Claim 1, in which the pitch angles of the two paths have the same sign. Oven according to Claim 1, 2 or 3, in which the numbers of helical windings of the first and second path are the same, and the pitch angles are the same size. Oven according to one of the preceding claims, in which the housing has an inlet opening and an outlet opening which are situated at the same level.

Inventors: LYGUM POUL, LYGUM, POUL
Applicants: KOPPENS BV, KOPPENS B.V.
Application year: 1993
Main classification: A21B1
IPC codes: A21B1