FR2558936A1 - MICROWAVE OVEN EQUIPPED WITH WAVE BREAKER - Google Patents

Abstract

1. A microwave oven compr sing a cooking enclosure (10), a microwave generator (12) delivering the microwave energy in the said enclosure (10) by the intermediation of a wave guide (14) carried on one of the walls (16) of the enclosure (10), and a wave stirrer (18) disposed at the mouth of the said wave guide (14) and comprising a rotating shaft (20) carrying a flange (22) equipped with a series of metallic blades (24) intended to ensure distribution of energy in the enclosure (10), characterized in that the shaft (20) of the stirrer (18) is mounted inclined in relation to an axis (28) perpendicular to the said wall (16) of the enclosure and is its elf subjected to an entrainment mechanism (30) which causes it to be slowly displaced, during its rotation, over a conical surface (32) the axis of which is identical with the said perpendicular axis (28), the said flange (22) and the blades (24) consequently describing, during their rotation about the shaft (20), a slow nutation movement about the said axis (28).

Description

Microwave oven equipped with a wave stirrer The invention relates to

equipped microwave ovens

of a wave brewer.

  More specifically, it relates to microwave ovens comprising a cooking chamber, a microwave generator or a microwave oven.

  waves delivering microwave energy in said

  encircled by means of a waveguide carried by 1 '

  one of the walls of the enclosure, and a wave brewer

  at the outlet of the waveguide and comprising a

  tative carrying a flange equipped with a series of metal blades

  to ensure the distribution of energy

inside the enclosure.

  The object of the invention is to improve the regularity of

  energy in all areas of the enclosure.

  According to the invention, the stirrer shaft is inclined

  relative to an axis perpendicular to the wall of the

  and is itself subjected to a drive mechanism which causes it to move slowly, during its rotation, on a conical surface whose axis coincides with said perpendicular axis, the flange and the blades of the stirrer thus describing during their rotation around the tree,

  a slow nutation movement about said axis.

  Thus, the inclination variations of the stirrer blades during the operation of the oven virtually ensure that no area of the internal space of the enclosure escapes.

to reach the microwaves.

  The features and advantages of the invention

  moreover, from the description that follows, as

  example, with reference to the accompanying drawings in which:

  FIG. 1 is a diagrammatic view of a microwave oven

  waves equipped with a wave brewer; Figure 2 shows

  on a larger scale, a vertical section of the wave stirrer and the drive mechanism; the

  FIG. 3 is a top view of the drive mechanism.

  and the housing that encloses it; Figure 4 is

  schematic view of the training mechanism

ment.

  The microwave oven of Figure 1 comprises a cooking chamber 10, a microwave generator 12 delivering 1 '

  microwave energy in the enclosure 10 through the medium of

  re of a waveguide 14 carried by the upper wall 16

  of the enclosure, and a wave stirrer 18 disposed at the

  waveguide 14 and comprising a rotary shaft 20

  carrying a flange 22 equipped with a series of metal blades

  24 to provide a distribution of energy in the enclosure 10. Between the stirrer 18 and the enclosure 10 is disposed a protective cover 26 of permeable material

in the microwave.

  The shaft 20 of the stirrer 18 is mounted inclined with respect to a vertical axis 28 and is itself subjected to a drive mechanism 30 which causes it to move slowly during

  its rotation on a conical surface 32 whose axis is con

  melted with the axis 28; the flange 22 and the blades 24 decribed

  thus, during their rotation around the shaft 20, a

  slow nutation movement about said axis.

  As can be seen in FIG. 2, the arm shaft 20

  it is mounted in an inclined bearing 34 arranged in a plate 36 that the drive mechanism 30 rotates

  slowly around the axis 28 on a horizontal circular seat

  zontal 38 arranged in a housing 40 fixed to the wall 16. The inclined bearing 34 is located in the center of the horizontal circular seat 38. The stirrer 18 is rotated by the cooling air stream of the microwave generator 12, this by

  action of this current (arrow F) on the blades 24.

  The driving mechanism 30 of the turntable 36 is

  consisting of a speed reducer interposed between the

20 and this plateau.

  As can be seen in FIGS. 3 and 4, this speed reducer comprises a conical gear 42 which is integral with the shaft 20 and which is engaged with a train of several

  gears which are carried by the plate 36 and whose last

  deny 44 is engaged with a fixed ring gear 46

  in the housing 40 and concentric with the vertical axis 28.

  This gear train comprises a first wheel 48 which is engaged with the bevel gear 42 and which is integral with a pinion 50. This pinion 50 is engaged with a second wheel 52 which is integral with the pinion 44. The first wheel

  48 and its pinion 50 are mounted on a bearing 54; the se-

  wheel 52 and its pinion 44 are mounted on a bearing

  56; the bearings 54 and 56 are located on the upper surface

upper shelf 36.

  Thus, the air stream (arrow F) rotates the wave stirrer 18 at a speed of the order, for example, of sixty revolutions per minute. This movement is communicated to the pinions and wheels 42, 48, 50, 52 and 44. The pinion 44,

  rolling in the ring gear 46, leads to this movement.

  its bearing 56 (arrow G in Figure 3) and hence

  the plate 36 in a slow rotational movement at the in-

  interior of the housing 40, this at a speed of the order, by

  example, one and a half turn per minute.

  Due to the inclination of the bearing 34 on the plate 36,

  the shaft axis 20 of the wave stirrer moves slowly

  on the conical surface 32 during the rotation of this shaftf that is to say that the stirrer 18, and therefore its blades 24 are animated, during their rotation, a slow nutation movement. The consecutive variations of inclination of the blades 24 ensure a good distribution of the energy a

  microwaves in all areas of the enclosure 10.

Claims (4)

claims   1. Microwave oven comprising a cooking chamber (10), a microwave generator (12) delivering the microwave energy in said chamber (10) via a waveguide (14) carried by one of the walls (16) of   the enclosure (10), and a wave stirrer (18) disposed   clogged with said waveguide (14) and comprising a rotary shaft   tif (20) carrying a flange (22) equipped with a series of metal blades (24) intended to ensure a distribution of the energy in the enclosure (10), cara ct ized in that the shaft ( 20) Brewer   (18) is inclined with respect to a perpendicular axis (28)   said wall (16) of the enclosure and is itself   put in a drive mechanism (30) which leads him to   slowly placing during its rotation on a conical surface (32) whose axis coincides with said perpendicular axis (28), said flange (22) and the blades (24) thus describing, during their rotation around the shaft (20); ), a movement   slow nutation around said axis (28).   2. Microwave oven according to claim 1, characterized in that, said wall (i6) being the upper wall of the enclosure (10), and said axis (28) being then vertical, the shaft (20) of the stirrer (18) is mounted in an inclined bearing (34) in a tray (36) which the drive mechanism (30) slowly rotates about said vertical axis (28) on a horizontal circular seat   (38) arranged in a housing (40) attached to said upper wall   re (16), said inclined bearing (34) being located in the center of the   said horizontal circular seat (38).   Microwave oven according to claim 2, characterized in that the stirrer (18) is rotated by the cooling air stream (F) of the   microwave generator (12), the drive mechanism (30)   of the turntable (36) consists of a reduction   speed controller interposed between the shaft (20) of the stirrer and this tray (36).   -6- 4. Microwave oven according to claim 3, wherein the speed reducer comprises a bevel gear (42) which is integral with the shaft.   (20) of the brewer who is engaged with a train of   gears each of which is mounted by a bearing (54,   56) implanted on the plate (36) itself, the last gear   stroke (44) of said train being engaged with a stationary ring gear (46) formed in the housing (40) and concentric with said   vertical axis (28), the latter gear (44) thereby entraluting   if the plate (36) in a slow rotational movement at 1 ' inside the housing (40).