Hot-air oven having an improved door-sealing member

Abstract

A hot-air oven for the preparation of food is provided. A cooking chamber delimited by walls is provided in a housing. A blower produces a hot-air stream in the cooking chamber, and a controller controls the progress of a cooking process. A rotatable basket for food can be introduced into the cooking chamber via an opening in one of the walls. During operation the basket is subjected to a hot-air stream. A closure element is connected to the basket and serves to close off the wall opening during operation. The closure element is supported relative to the basket via a pivot bearing that is coaxial with an axis of rotation of the basket.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a hot-air oven for the preparation of food. The oven includes a housing that has a cooking chamber delimited by four side walls, one of which can be embodied as a door, as well as a bottom wall and a top wall. A blower means is provided for producing a hot-air stream in the cooking chamber. A control means is also provided for controlling the progress of a cooking process. A rotatable basket is provided for food and can be introduced into the cooking chamber via an opening in one of the walls, whereby during operation a hot-air stream passes through the basket. In addition, during operation the wall opening is closed off by a closure element that is connected to the basket.

[0002] A hot-air oven of this type is known, for example, from the European Patent EP 0734503 B1. In such a hot-air oven, a basket for the products that are to be prepared is mounted in a cooking chamber so as to be rotatable about an axis. The basket can be withdrawn out of the cooking chamber in the axial direction, and is provided on its free end with a round closure plate that is disposed concentric to the axis of rotation. This closure plate is fixedly connected with the basket, and when the basket is completely inserted seals off the cooking chamber toward the outside. A seal is provided between the housing, which is stationary during operation, and a similarly stationary, pivotable door on the one hand and the rotating closure plate on the other hand; during operation, the seal is similarly stationary and the closure plate of the basket slides over the sealing surfaces of the seal. This form of the sliding seal in practice, especially after longer periods of operation, leads to sealing problems. In this sealing region, steam from the cooking chamber, or smoke that might develop, can escape, which in addition to the possible formation of odor can also make the surface of the oven dirty.

[0003] It is therefore an object of the present invention to improve a hot-air oven of the aforementioned general type in such a way that the sealing of the cooking chamber is improved in the region of the removal opening for the basket.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] This object, and other objects and advantages of the present invention, will appear more clearly from the following specification in conjunction with the accompanying schematic drawings, in which:

[0005] FIG. 1 is a perspective view of one exemplary embodiment of an inventive hot-air oven; and

[0006] FIG. 2 is a cross-sectional view through the sealing region of the door of the hot-air oven of FIG. 1.

SUMMARY OF THE INVENTION

[0007] The hot-air oven of the present invention is characterized primarily in that the closure element is supported relative to the basket in a pivot bearing that is coaxial with the axis of rotation of the basket.

[0008] Since the closure element is supported relative to the basket in a pivot bearing that coincides with the axis of rotation, the basket can be rotated during operation while the closure element remains stationary. The closure element is preferably provided with a sealing zone that is circular cylindrical and rotationally symmetrical relative to the support axis. In this connection, the seal, which is associated with the housing of the door, is preferably disposed against the outer peripheral surface of the cylindrical region of the closure element. To simplify handling, it is furthermore possible to provide a handle on that surface of the closure element that faces away from the cooking chamber. By means of this handle, the basket can be withdrawn out of the cooking chamber. The operation can be made particularly reliable if, as a function of a control means, the basket is withdrawn out of the cooking chamber only when an opening provided on the basket is directed upwardly. To empty the basket, it is furthermore advantageous for the basket to be rotatable, by means of a motor, out of this position and into a discharge or issuing position. Pursuant to a particularly straightforward embodiment of the inventive hot-air oven, when the basket is withdrawn from the cooking chamber a mechanically fixed coupling is effected between the closure element and the basket. This can be effected by a manual actuation of a coupling or catch that is associated with the handle.

[0009] Further specific features of the present invention will be described in detail subsequently.

DESCRIPTION OF PREFERRED EMBODIMENTS

[0010] Referring now to the drawings in detail, a hot-air oven is illustrated in perspective in FIG. 1. The hot-air oven has three fixed side walls 2 as well as a side wall 4 that is provided with a door 3 and that is to be opened. The upper side is formed by a top wall 5, and the under side is formed by a non-visible bottom wall. The walls 2-5 surround the interior of the hot-air oven, a portion of which is embodied as a cooking chamber.

[0011] The side wall 4 and the door 3 have a circular opening 7 through which a mesh-type basket 8 can be introduced into the cooking chamber.

[0012] The basket 8 is rotatably mounted in the cooking chamber in a manner known per se. During operation, a hot-air stream passes through the basket, which is rotated about an axis that is parallel to the direction of insertion and that coincides with the axis of symmetry of the opening 7.

[0013] At one end face, the basket 8 is provided with a closure element 10 that has a handle 11 for pulling the basket 8 out or pushing it in.

[0014] The region of the opening 7, and the outer end of the basket 8, are illustrated in greater detail in the cross-sectional view of FIG. 2. The same components have the same reference numerals.

[0015] In addition to the circular disc shaped outer portion of the closure element 10 that is visible in FIG. 1, and to which the handle 7 is fastened, the closure element has a cup-shaped portion 13 that is embodied to be rotationally symmetrical about an axis of rotation 14, and that is welded or otherwise fused to the outer portion of the closure element 10. Disposed centrally and perpendicular to the closure element 10 is a bearing or support pin 15 that passes through the portion 13 and in the direction toward the basket 8 extends beyond the basket. The pin 15 carries two bearing discs 16, which are disposed on either side of an end face 17 of the basket 8. A central sleeve spaces the discs 16 apart, so that the end face 17 of the basket 8 remains rotatable about the axis 14 between the discs 16. A cap nut secures the discs 16 to the pin 15.

[0016] The door 3, which is provided with the opening 7 that is similarly disposed approximately concentrically relative to the axis 14, is, for receiving the described closure element 10, provided with a sealing means 20 that is made of an elastomeric or rubber-elastic material and is provided with a free sealing lip 21 that faces the closure element 10.

[0017] During operation, the interior of the basket 8 can be filled with food, for example frozen french fries. The basket 8 is then inserted via the handle 11, in the direction of the axis 14, into the housing of the hot-air oven 1, stated more precisely into the cooking chamber, as a result of which the sealing lip 11 of the sealing means 20 rests against the outer peripheral surface 13 of the cup-shaped portion of the closure element 10. The cooking chamber is thereby sealed off relative to the outer atmosphere. That portion of the closure element 10 that projects radially beyond the peripheral surface 13 secures the region of the sealing means 10 and the sealing lip 20 against external contact and also optically seals the cooking chamber.

[0018] To cook the food, the basket 8 is rotated about the axis 14 and is subjected to a hot-air stream. In this connection, the end face 17 of the basket 8 also rotates about the axis 14 between the discs 16, while the closure element 10, with its attached parts, remains stationary. The sealing of the cooking chamber in the region of the contact surface between the sealing lip 21 and the outer peripheral surface 13 is stationary due to the mechanical uncoupling in the region of the pivot bearing formed by the elements 16 and 17.

[0019] When the cooking process is concluded, the basket 8 is rotated into a starting position in which its basket opening is toward the top. Via the handle 11, the basket 8 can then be pulled out of the housing until it abuts thereagainst. The opening of the basket is then rotated downwardly by a motor, so that the food product issues from the basket 8.

[0020] Pursuant to another embodiment, the rotation of the basket into a discharge position by motor can be replaced by a manual rotation via the handle 11. For this purpose, a fixed coupling, which is not illustrated in FIG. 2, is required that engages only when the basket 8 is withdrawn out of the cooking chamber.

[0021] On the whole, there results a sealing of the hot-air oven in the region of the door 3 that, relative to the state of the art, and as a consequence of the sealing elements, of the sealing means 20 with its sealing lip 21, and of the peripheral surface 13, which are stationary relative to one another during operation, ensures a considerably improved and more durable sealing of the cooking chamber relative to the atmosphere.

[0022] The specification incorporates by reference the disclosure of German priority document 10 207 638.3 of Feb. 22, 2002.

[0023] The present invention is, of course, in no way restricted to the specific disclosure of the specification and drawings, but also encompasses any modifications within the scope of the appended claims.

Claims

1. a hot-air oven for preparation of food, comprising:

a housing having a cooking chamber that is delimited by four side walls one of which can be embodied as a door, as well as by a bottom wall and a top wall;

a blower means for producing a hot-air stream in said cooking chamber;

a control means for controlling progress of a cooking process;

a basket for food, wherein said basket is rotatable and is introducible into said cooking chamber via an opening in one of said walls, wherein during operation said basket is subjected to a hot-air stream;

a closure element that is connected to said basket and serves to close off said wall opening during operation; and

a pivot bearing that is coaxial with an axis of rotation of said basket, wherein said closure element is supported relative to said basket via said pivot bearing.

2. A hot-air oven according to claim 1, wherein said closure element is provided with a sealing region that is circular cylindrical or annular and is rotationally symmetrical relative to said axis of said rotation.

3. A hot-air oven according to claim 2, wherein a sealing means is provided that during operation is stationary and that is associated with said housing or said door, and wherein said sealing means rests against an outer peripheral surface of said sealing region.

4. A hot-air oven according to claim 1, wherein a surface of said closure element that faces away from said cooking chamber is provided with a handle for withdrawing said basket out of said cooking chamber.

5. A hot-air oven according to claim 1, wherein as a function of said control means, said basket can be withdrawn from said cooking chamber only if in a normal position an opening provided on said basket is directed upwardly.

6. A hot-air oven according to claim 5, wherein said basket is rotatable out of said normal position into a discharge position.

7. A hot-air oven according to claim 6, wherein said basket is rotatable by means of a motor.

8. A hot-air oven according to claim 1, wherein a mechanically fixed coupling is provided between said closure element and said basket, and wherein said coupling is in engagement when said basket is withdrawn from said cooking chamber.

9. A hot-air oven according to claim 8, wherein said coupling is effected by a manual actuation of a coupling or catch that is associated with a handle of said closure element.