GB2028491A - Microwave oven and exhaust vent - Google Patents

Abstract

An assembly for combining an appliance, for example a microwave oven, with a range vent hood is disclosed. The assembly comprises the appliance housing (14) supported in a structure (23) for mounting on a wall or an overhead cabinet above a conventional range. The support structure (23) includes a back wall (24) upon which ribs (44a, 44b) are formed so as to space the rear of the housing (14) from the back wall to form a channelized air space (46) therebetween. A plate (32) is attached to a lower portion of the back wall and extends forwardly toward and beneath the front of the appliance housing (14) to form a second channelized air space (38) between the plate and bottom of the housing. The two air spaces thus formed, communicate with one another to permit cooking gases and vapors (48) from the range to be drawn by a fan (42) upward through openings (50) in the plate, thence through the two air spaces (38, 46) and out of the assembly on or near a top rear portion thereof. Ventilating means (54) for the microwave oven completely separate and distinct from the first and second channelized air vent spaces is also provided so that the range hood vent feature and the microwave vent feature of the assembly can be used independently from one another or concurrently as desired. <IMAGE>

Description

SPECIFICATION Combined support structure and ventilation system This invention relates generally to an assembly for combining an auxiliary cooking appliance, such as a microwave oven, with a vent hood used in association with a cooking range of the traditional type.

One such known assembly is a unitary structure having a traditional electric range mounted in a lower portion and a microwave oven mounted in an upper portion. A vent hood assembly for the traditional electric range is formed above the microwave oven with an inlet port located above the front of the microwave oven. As a result, gases and vapors generated while cooking on the traditional range rise and are drawn upward across the front face of the microwave oven and into the range vent inlet port. Should the microwave oven be operated while such cooking gases and vapors are rising from the electric range across the front face of the former, a portion of these moisture and grease laden gases and vapors may be drawn into the microwave oven ventilating system, the inlet port to which is typically located in the bottom of the microwave housing.In such an event, the electronic components of the microwave oven can become contaminated with grease, vapors and other gaseous cooking products generated by the electric range below.

In addition, while combination products of the above general type have been known in the art, they have generally been larger than desirable.

Specifically, prior art combination oven and exhaust vent structures have projected outwardly from the mounting wall to an extent which substantially obstructs an average user's view of the range or cooking appliance located therebelow. This is more particularly true where the range has its controls located in the rear thereof.

Briefly, our invention provides an assembly for combining an appliance with a range vent hood which includes means for forming a housing for the appliance, means for supporting the housing and means for spacing at least a portion of the housing from the supporting means to provide an air space therebetween. A means for channelizing the air space between an inlet and an outlet end, and a means for venting gases and vapors which enter the inlet end from the outlet end is also provided.

Preferably the assembly also provides another air conduit system independent of the one noted above which moves air from outside the assembly through the electronic component compartment and the oven cavity and back outside of the assembly. Each of the circulation systems includes its own power driven fan to move air.

In the accompanying drawings, FIG. 1 shows an illustrative exploded perspective view of an oven/vent assembly embodying the invention, with some air ducts omitted for clarity from the module 9; FIG. 2 shows an illustrative exploded perspective view of the oven operating module of the assembly showing the air duct appendages displaced from the main frame and the air flow opening utilized in the air circulation system; FIG. 3 is an illustrative perspective view of the module of FIG. 2 mounted in a support assembly highlighting the air circulation paths through the mounted appliance; FIG. 4 shows a top plan view of the assembly of FIG. 3; FIG. 5 shows a cross-sectional elevational view of the assembly of FIG. 3 as generally viewed along iines 575 of FIG. 4;; FIG. 6 shows a fragmented side elevational view of the assembly as generally viewed along lines 6-6 ofFIG. 4, with selected parts included to illustrate certain features of the air ventilating system.

Referring to the drawings, the microwave oven appliance is seen to generally comprise a support assembly 11 including a main support 23, a top cover 36, and a bottom closure 32 which are coupled togethertoform an enclosure which supports a microwave oven operating module or assembly 9. The overall assemb!y and the installation method therefor is described in detail in concurrently-filed, 2,028,493 application Serial No. 7925694 entitled COMBINATION MICROWAVE OVEN AND EXHAUST VENT AND INSTALLATION MOUNTING METHOD THERFOR, which disclosure is hereby incorporated by reference. The description of the various components of the appliance will be given herein only to the extend necessary to understand the air circulation arrangements incorporated therein.

The microwave oven assembly or module 9 includes a cooking chamber 10 and an adjacently disposed oven control compartment 12 which houses an electronics package for operating the oven, both being located within a housing or main frame 14 and separated one from the other by a partition wall 1 6 of FIG. 2. Access to the cooking chamber 10 is had through a door 18 mounted on a door frame 20, the latter being joined along its top and bottom edges to forward end portions of the upper and lower surfaces of the main frame 14. The door 18 is hingedly supported at the left side thereof and is operable by means of a handle 9. A cover piece 3 closes the front facing opening to the compartment 12.

The main frame 14 of the module 9 is generally composed of sheet metal in accordance with concurrently-filed 2,829,180 application Serial No. 7925695 entitled UNITIZED OVEN STRUCTURE FOR A MICROWAVE OVEN, which disclosure is hereby incorporated by reference. That application may be referred to for.

details of construction for the sheet metal body of the module 9, which forms no part of this invention and the details of which are being omitted for the sake of brevity. Briefly, however, the sheet metal body or frame 1 4 includes a top wall 5, sidewalls 4, a rear wall 6 and a bottom wall -7. The top wall 5 has a pair of elongated rails 28a, b which have a generally inverted L-shaped crosssection formed along the sides of the top wall and extending substantially the entire depth of the module.

The frame 14 has appendages to the top wall 5 including a waveguide 82 and a mode stirrer housing 84. The waveguide conducts microwave energy generated by a magnetron (not shown) located in the compartment 12 into the mode stirrer housing 84 from whence it is directed downwardly into the microwave oven cavity 10 in a manner well known in the art.

The oven vent cavity 10 is closed except for the door opening and two air permeable or perforated areas, the first area 88 being in the right sidewall, through the partition 16, and the second area 90 being located in the top wall at the left of the assembly. A combination lamp housing and air guide member 92 covers the perforate area 90 and operates to guide air from the oven chamber to the exterior of the assembly as will be explained hereinafter. An air directing duct 80. FIG. 2, is attached to the top wall of the module 9 over the waveguide 82 and mode stirrer housing 84 which also aids in directing air through the assembly which exits the electronics compartment through an opening 76, FIG. 2, in the top wall thereof.An air duct 68 is also supported in the chamber 12 for funnelling air along its various paths as will be explained hereinafter in greater detail.

The main support member 23 provides essentially the entire support for the arrangement, and for this purpose is constructed of a relatively heavy guage sheet metal. The main support member 23 includes a back wall 24, adapted to fit substantially flush against a conventional wall board 1 6, and a pair of appliance supporting integral sidewalls 26a and 26b. The back wall 24 has an opening to provide a vent path out of the assembly along the back thereof, the opening being either blocked by a suitable covering piece or brought into air communication with a range exhaust flue or conduit for venting to the exterior as explained hereinafter.

The back wall 24 contains on its interior surface a pair of raised walls or ribs 44a and 44b for enhancing the strength and rigidity thereof. The ribs also perform the function of directing exhaust air through the structure.

Multiple rows of holes 41 extend across the back wall 24 through selected ones of which at least one lag screw 25 or other suitable threaded fasteners can be inserted to securely mount the assembly to the wall board 1 6 and to at least one wall support member or stud 29. A pair of holes 27 located in the upper right and left hand corners of the back wall 24 permits the main support member 23 to be further secured to thezvall board 1 6 with suitable fasteners such as a pair of toggle bolts 30.

In order to provide support for the oven module 9 when inserted into the support assembly, the sidewalls 26a and 26b have formed thereon a pair of rails 1 5a and 15b. The rails are formed by punching out and bending inwardly an elongated piece of sheet metal, the openings 59 resulting from this process. The rails 15a and 15b extend front to rear across substantially the entire depth of the sidewalls 26a and 26b.

The sidewalls 26a and 26b on the support member 23 are provided with inwardly directed fianges 37 on the top edges thereof, the latter flanges having a plurality of slots 39 formed therein adjacent the four corners of the member 23.

'These openings are used in combination with similar holes 33 in the cover 36 to couple the support assembly to an overhanging cabinet, if needed.

The cover 36 is a generally inverted U-shaped member formed from a relatively light guage of sheet metal comprising sidewalls or arms 34 which extend downwardly at right angles away from a top wall or central portion 5. The wall 35, as alluded to in the previous paragraph, is provided with a set of openings 33 which are aligned with the set of slots 39 in the member 23 so that suitable fasteners, such as screws, may be inserted therethrough to attach the assembly including the cover 36 and support member 23, to an overhead cabinet. The cover is positioned over the member 23 so that the arms 34 thereof straddle the sidewalls 26a and 26b on the outside thereof. Aligned holes (not shown) are provided in the cover and member 10 through which screws may be inserted to hold these pieces together.The exterior or outside faces of the cover 36 are finished in a conventional manner to provide an acceptable pleasing outward appearance for the arrangement.

The main support member 23 also has suitable formations for supporting a power driven, exhaust air moving assembly 43 (FIG. 1) including a fan or blower wheel 42 located centrally of the member 23 and in air communication with the closure plate 32. The assembly 43 is attachable to the support member 23 prior to insertion of the module 12.

A panel or closure plate 32 serves to close off the bottom wall of the support assembly. The plate 32 includes tabs 55 along the rear edge thereof which interfit with slots 57 along the lower edge of the back wall 24, FIG. 5. The front edge of the cover plate 52 has an inwardly turned lip 47 which resiliently cooperates with a mating formation on the lower front edge of the module 12 to hold the front of the plate 32 in place. The plate 32 is provided with appropriate rectangular vent openings 30 having air intake filters 31 positioned therein. The base plate 32 may also be provided with a translucent panel 49 above which light-emitting means may be positioned to illuminate the range heating surface located below the oven.

The oven is assembled by joining the cover 36 and plate 32 to the support member 23 which results in a support assembly or enclosure closed on the top, rear, sides and bottom, but open at the front. The module 12 is then slid rearwardly irito the enclosure along rails 1 5a and 15b until the rear wall 6 of the module 9 abuts the ribs 44a and 44b.

It should be noted that when the module 12 is positioned within the support assembly thus formed, a space is created between the top wall 35 of the cover 36 and the top wall 5 of the oven module 9. It is in this space that the lamp mounting and air directing duct 92 and duct 8 are positioned. This space is closed at the front of the assembly by an air permeable grille 75.

Having explained in general the basic elements of the microwave oven and exhaust vent assembly of this invention, a detailed description will now be given of the novel air circulating arrangements incorporated thereinto which are the specific subject of this application.

The back wall 24 of the main support member 23 extends below the bottom wall 7 of the microwave oven module 1'2 such that a substantial air plenum of space 38 is formed between the plate 32 and the bottom surface of the oven main frame 14. This gap or plenum chamber 38 extends horizontally along the longitudinal dimension of the assembly between the sidewalls 26a, b. The sidewalls 34 of the cover 36 overlying the sidewalls 26a, b may also be employed or cooperate to enclose the ends of the gap 38. It will be noted that the plate 32 extends horizontally forward from its connection with the back wall 24 to a crease or bend line 40 to provide an enlarged space along a rear portion thereof in which is located a cylindrically-shaped tangential fan or blower wheel 42.The blower wheel 42 has its longitudinal axis extending parallel to the plane occupied by the back wall 24 and bottom wail 7 of the module 12.The blower wheel 42 is, in turn, carried within an air channeling piece 45, FIG. 5, of generally J-shaped cross-section connected to and supported by the back wall 24. Such a tangential fan operates to draw air into the bladed rotating cylinder thereof in one direction and to direct the same air away from the cylinder in a direction approximately 90 degrees displaced from the direction of flow of the entering air. In addition, by positioning the bulky impeller of the blower in the enlarged rear portion of the plenum 38, the plate 32 is permitted to slope upwardly toward the front and intersect the module 12 near the lower edge of the aceess door 20.This latter feature hermits greater visibility of the-space underneath the assembly when it is mounted in an elevated position. Thus, by locating the wheel 42 in the preferred lower rear corner position as shown in FIGS. 3-5, an intake air stream 48 is created which takes a right angle turn in direction in passage through the blower wheel 42. A greater efficiency thus results from locating the blower wheel 42 at the 90 degree bend in the path of the air stream 48 than would result if the blower wheel 42 were located elsewhere.

The pair of raised ribs or spacers 44a and 44b carried by the back wall 24 separate the back wall 24 from the rear surface 6 of the oven module 12.

A vertically extending air duct or conduit 46 is thus formed, the sides of which are defined by the opposing diagonally extending ribs 44a, b, and the front and back of which are defined by the rear wall 6 of the oven module 12 and the back wall 24, respectively. The vertically extending air conduit 46 communicates along a lower portion thereof with the plenum 38 in the region at the lower rear of the assembly in which the blower wheel 42 is disposed. Accordingly, the adjoining plenum 38 and conduit 46 jointly form a continuous air conducting conduit along which exhaust fumes, gases and vapors, as generally designated in FIGS. 3 and 5 by means of arrows 48, can pass through the assembly.Such gases 48 enter through filters 31, being drawn into and through the plenum 38 with the aid of the rotating blower wheel 42 which redirects such gases upwardly through the conduit 46 and opening 71 in the cover 36 and out the top of the assembly through a vent port 52. By reason of the air flow path 48 formed in the assembly of our invention, the assembly is adapted for use not only as a microwave oven but also as a vent hood for a conventional cooking range. Accordingly, the assembly may be mounted to a wall or to the floor of an elevated wall cabinet such that the plate 32 is spaced a suitable distance above the cooking elements on the surface of a conventional kitchen range. In this manner, the space traditionally occupied by a conventional range vent hood can be more efficiently utilized.The oven asssembly of our invention thus may be substituted in place of the usual vent hood such that the vent hood function is retained. At the same time, the oven assembly in conventiently located above and near the conventional cooking range without the loss of valuable cabinet or counter space. The vent port 52 can, of course, be connected in any suitable manner to a conventional wall mounted vent or flue structure as found in a large number of residential kitchens.

The vent port 52 is preferably formed on Lshaped plate 53 which removably overlies an upper rear corner portion of the cover 36. The opening 71 underlies and registers with the opening in the vent port 52. The vent port 52 may then be connected to an overhead flue in the usual manner to permit the exhaust of gas fumes from the surface of a traditional cooking range upwardly into and along the spaces 38 and 46, thence through the port 52 and out the top of the assembly as shown in FIG. 5. In the alternative, the plate 53 may be installed, over the top rear corner portion of the cover 36 so that the port 52 projects rearwardly behind an upper portion of the back wall 24 and the opening therein aligns with the opening 73 in the rear wall 24, FIG. 5.The latter arrangement will permit the exhaust gases 48 flowing in the space .46 to exit the assembly through the opening 73 in the upper portion of the back wall 24, as indicated by an arrow 48a in FIG.

5.

Thus having explained the nature and use of the assembly of our invention as a vent hood for a conventional cooking range located beneath the plate 32, reference is now made to the air ventilating features of the assembly relating to the microwave oven chamber 10 and oven electrical control compartment 1 2 with particular reference to FIGS. 3---6. A stream 54 of ventilating air for the microwave oven operating system of the assembly enters the latter through a grilled air inlet port 56, FIG. 3, located at the top righthand side of the front of the assembly over the control compartment front panel 3. Thereafter, the stream 54 is drawn horizontally and rearwardly across the upper right surface of the oven main frame 14 directly above the compartment 12.The top surface 35 of the cover 36 and the upper surface of the main frame 14 jointly define an enclosed channel for the stream 54 in this region of the assembly. The air stream 54 is drawn over the upper rear corner of the oven main frame 14 and thence downwardly along an air conduit 58 provided between the back of the frame 14 and the back wall 24 of the support assembly 22 to the right of the diagonally extending portion of the rib 44a as viewed in FIG. 3. As the stream 54 flows downwardly through the conduit 58, it is drawn through a series of louvers 60 formed in the back of the oven main frame 14 and into the interior of the control compartment 12.Upon entering the control compartment 12, the stream 54, which has previously been relatively laminar in character, flows through and around the various electronic and power supply components, such as a transformer 62, to become disrupted into a turbulent airflow pattern as indicated in FIG. 3 by a looping air flow pattern. This turbulent flow serves to cool the electronic components in the compartment 12 generally.

After cooling various electronic and power supply components, the stream 54 is drawn into the low pressure input side at the base of an air moving means or blower 64 wherein it is compressed into a relatively high pressure volume of air and emitted from a high pressure output side 65 directly into an opening 66 of a plastic air directing duct 68 (see FIGS. 2 and 4). The duct 68 contains a housing 70 in which a conventional microwave signal generating magnetron, not shown, is disposed. Attached to the magnetron is a series of vertically stacked cooling fins or heat exchanger plates 72, FIG. 3, between and across which the high pressure air stream 54 emitted from the blower 64 is directed.

Since the blower 64 may generate a considerably greater volume of high pressure air than can be passed through the relatively closely spaced plates 72, an air stream 54a is vented which bypasses the plates 72 on one side thereof.

This by-pass air stream 54a flows upwardly along a ramp 76 formed in the duct 68 and through a rectangular opening 78 in the upper surface of the oven main frame 14. Thereafter, the by-pass air stream 54a flows through an exhaust duct 80, FIG. 2, attached to the top of the microwave waveguide 82 and a mode stirrer housing 84 located on the upper surface 5 of the module 9 and is exhausted out of the assembly through an air outlet port 86 and grille 75 above the oven door 18.

Now as to the main air stream 54 which does pass between and through the heat exchanger plates 72, the same is directed against a perforated portion 88 of the partition 16. Here again, the volume of air in the stream 54 which passes through the plates 72 may be greater than that required to ventilate the oven chamber 10. In such a case, the guage and density of the performations in the wall portion 88 should be selected to allow only the desired volume of ventilating air to flow through the partition 1 6 into the cooking chamber 10. Any excess volume of output air from the plates 72 not required to ventilate the chamber 10 will strike the portion 88 of partition 16 within the confines of the plastic chamber 68 and will be diverted sidewardly up the ramp 76 to join the by-pass air stream 54a to ultimately exit the assembly through the port 86.

The volume of the air stream 54b which passes through the perforated wall portion 88 thereafter circulates through the chamber 10 to combine with cooking gases, after which the air stream 54b and various cooking gases exit through a perforated section 90 formed in the upper surface of the main frame 14 and flows forwardly along a guide member 92. Ultimately, the air stream 54b exits the front of the assembly through a grilled exhaust port 94 located above the door 18 on the opposite side of the assembly from which the air stream 54 originally entered.

It will be noted that the microwave ventilating air stream 54 is completely separate and distinct from the range vent air stream 48 from entry to exit of the assembly. Thus, the assembly is readily adapted for use of the microwave oven air flow system or the range vent system separately and independently of one another, as well as con currently. This is a particularly advantageous feature of our invention where the microwave air stream 54 is not sufficiently strong to operate a flue damper mechanism of the type found in the kitchens of some homes.

Claims (14)

1. An assembly comprising: a housing having a bottom and a rear serface, a support for said housing, means for spacing said rear surface from a back wall of said support to provide a first air channel, plate means spaced from said bottom surface to form an air space therebetween, means enclosing the sides of said air space to form a second air channel, said first and second air channels communicating with one another, and means for forcibly moving air from below said plate means through an opening in said plate means into said second air channel, and through said second air channel into and through said first channel.

2. The assembly of Claim 1 wherein said spacing means comprises ribs on said back wall.

3. The assembly of Claim 1 or Claim 2 wherein said plate means projects horizontally forward from said back wall a selected distance to a bend line and thereafter extends diagonally upward to engage a bottom portion of said housing.

4. An assembly according to any one of the preceding claims wherein said side enclosing means comprises a pair of sidewalls formed on opposite sides of said back wall and extending forwardly along the-sides of said housing and plate means.

5. An assembly according to any one of the preceding claims wherein said means for forcibly moving air comprises blower means disposed intermediate said plate and said housing.

6. An assembly according to any one of the preceding claims further comprising a cover disposed over said housing.

7. An assembly according to any one of the preceding claims further comprising means separate and distinct from said first and second air channels for ventilating said housing.

8. The assembly of Claim 2 wherein a pair of said ribs extend horizontally toward one another to a position in which they are a first selected distance apart and thence extend diagonally upward along said back toward one another until they are a second selected distance apart.

9. The assembly of Claim 2 further comprising a tangential blower having an elongated cylindrically shaped bladed fan disposed below said ribs between said plate means and housing.

10. The assembly of Claim 4 wherein said side enclosing means also comprises a cover for said housing having a top surface and a pair of sidewalls extending downwardly from the sides of said top surface across the sides of said air space.

11. The assembly of Claim 6 further comprising vent port means removably disposed over a portion of said cover and back wall for venting said first air channel.

12. The assembly of Claim 8 further comprising blower means disposed between said plate means and housing below and- between the horizontally extending portions of said ribs for directing gases and vapors upward into said first air channel between said diagonally extending portions of said ribs.

1 3. In combination, an assembly according to any one of the preceding claims and a microwave oven appliance disposed in said housing.

14. An assembly according to Claim 1 and substantially as herein described with reference to the accompanying drawings.