US3841062A

US3841062A - Grease extraction ventilator

Info

Publication number: US3841062A
Application number: US00314278A
Authority: US
Inventors: V Molitor; A Gallagher
Original assignee: STAINLESS EQUIPMENT Co
Current assignee: MOLITOR INDUSTRIES Inc
Priority date: 1972-12-11
Filing date: 1972-12-11
Publication date: 1974-10-15
Anticipated expiration: 1991-10-15

Abstract

The grease extraction ventilator includes a water bath which is engaged by the air drawn from the cooking area over an upright front plate and down beneath a curved baffle, the lower end of which may be adjusted to cause the air to impinge against the water bath and push it upwardly against a concave deflector, with the entrapped grease and other products of combustion flowing, with water, over the upper edge of the plate at the rear of the water bath. Additional water droplets are thrown out of the air, while these droplets and moisture condensing on the top of the curved baffle cool the underside of this baffle, while flowing back to the water bath. A portion of the underside of this baffle is above the cooking area, and the cooling of the baffle tends to minimize the task of keeping it clean. The ventilator may be made in either the up-draft or down-draft form, while a safety baffle is held open by a cable and fused links, but closes when the temperature in the plenum melts the links. Makeup water is supplied during cooking, while a detergent may be placed in the water bath and the cold water therein replaced by hot water, the air flow carrying water droplets and detergent into the interior baffle arrangement, for cleaning purposes. The suction fan is then turned off, and hot water sprayed into the interior, to wash off any collection of grease and the like which has previously been acted on by the detergent. Thus, the inside surfaces of the ventilator do not require manual cleaning.

Description

Unite States Patent [191 Molitor et a1.

[4 1 Oct. 15,1974

1 1 GREASE EXTRACTION VENTILATOR [75] Inventors: Victor D. Molitor, Denver; Arlen W;

Gallagher, Arvada, both of Colo.

[73] Assignee: Stainless Equipment (10.,

Englewood, C010.

[22] Filed: Dec. 11, 1972 [21] Appl. No.: 314,278

[52] US. Cl. 55/223, 55/244, 98/115 K [51] int. Cl Bold 47/02 [58] Field of Search 55/84, 95, 86, 239, 244, 55/248, 2231;98/115 K [56] References Cited UNITED STATES PATENTS 3,055,285 9/1962 Gaylord 98/115 K 3,065,687 1 1/1962 Graswich et a1. 98/115 K 3,370,404 2/1968 Lepper 55/248 3,494,108 2/1970 Moragne 55/233 3,624,696 11/1971 Cohen et al. 55/248 3,731,462 S/l973 Costarella et a1 55/228 Primary ExaminerCharles N. Hart Attorney, Agent, or Firm1-1orace B. Van Valkenburgh; Frank C. Lowe [57] ABSTRACT The grease extraction ventilator includes a water bath which is engaged by the air drawn. from the cooking area over an upright front plate and down beneath a curved baffle, the lower end of which may be adjusted to cause the air to impinge against the water bath and push it upwardly against a concave deflector, with the entrapped grease and other products of combustion flowing, with water, over the upper edge of the plate at the rear of the water bath. Additional water droplets are thrown out of the air, while these droplets and moisture condensing on the top of the curved baffle cool the underside of this baffle, while flowing back to the water bath. A portion of the underside of this baffle is above the cooking area, and the cooling of the baffle tends to minimize the task of keeping it clean. The ventilator may be made in either the up-draft or down-draft form, while a safety battle is held open by a cable and fused links, but closes when the temperature in the plenum melts the links. Makeup water is supplied during cooking, while a detergent may be placed in the water bath and the cold water therein replaced by hot water, the air flow carrying water droplets and detergent into the interior baffle arrangement, for cleaning purposes. The :suction fan is then turned off, and hot water sprayed into the interior, to wash off any collection of grease and the like which has previously been acted on by the detergent. Thus, the inside surfaces of the ventilator do not require manual cleaning.

15 Claims, 18 Drawing Figures PAIENIEUBCT 1 1 4 3; 841 U62 SHEET 1 BF 5 PAIENIEDnm 1 5mm SHEH 2 @F 5 PAIENTEB um I 51814 SHEEI 30? 5 GREASE EXTRACTION VENTILATOR This invention relates to grease extraction ventila-' I tors, and more particularly to such ventilators for use with cooking equipment, such as stoves, ranges, broilers and the like.

Grease extraction ventilators for use with cooking equipment have been developed through the years, so that such equipment is now available which will operate satisfactorily under normal circumstances, but leaves much to be desired when unusual circumstances are encountered. Also, such equipment requires regular and laborious cleaning, normally by hand, in order to prevent an accumulation of grease in and about the ventilator. An accumulation of grease in and about the ventilator is highly undesirable, since it constitutes a very definite and dangerous fire hazard. However, due to the labor involved in cleaning such ventilators, many operators are inclined to scrimp on cleaning, thereby permitting a dangerous accumulation of grease. More recently, the problem of air pollution has become a serious one. A grease extraction ventilator, which does not successfully extract the grease, permits greasy vapors and similar contaminants to escape through the flue into the outside air, thereby adding to the pollution burden on the already polluted air which many persons breathe. Another problem encountered with grease extraction ventilators is that of actual fire on a broiler or other cooking equipment which can become out of control, particularly if there is any sort of grease accumulation in the interior of the ventilator or in the ducts leading to the discharge flue. Grease extraction ventilators are normally associated with a duct in which a suction fan pulls a sufficient volume of air through the ventilator that smoke and the like is removed from the cooking equipment. However, this flow of air acts to suck any flames into the ventilator and thereby ignite grease therein. Thus, although a tire damper can be closed, the heat may be sufficient that grease deposited beyond the damper will ignite, thereby producing another tire, even though the original tire on the broiler or other cooking equipment may be extinguished.

One of the particularly disagreeable tasks in cleaning prior grease extraction ventilators is the necessity for the operator to open up the ventilator and reach inside it, in order to clean the inside surfaces. Some of the ventilators are quite complicated in construction, while the surfaces upon which grease might be deposited are not easy to reach, thus requiring considerable dexterity and contortionistic movements, in order to reach and also adequately clean all of the interior surfaces.

Among the objects of this invention are to provide a novel grease extraction ventilator, as for cooking equipment and the like; to provide such a ventilator which extracts grease and cooking vapors as they are produced, rather than permitting all of them to become deposited on the interior walls thereof; to provide such a ventilator which is readily cleaned; to provide such a ventilator which includes a body of water which is agitated by the air sucked through the ventilator and thereby removes grease and vapors by both entrapment and condensation; to provide such a ventilator in which the extracted grease and condensed cooking vapors are continuously removed; to provide such a ventilator which does not require the operator to manually clean any difficult to reach inside surfaces thereof; to provide such a ventilator in which the fire hazard is effectively reduced; to provide such a ventilator in which flames from the cooking equipment which may be drawn into the ventilator tend to be extinguished; to provide such a ventilator which may exist in more than one form; and to provide each such form of ventilator which is relatively simple in construction, reasonable in cost and effective and efficient in operation.

The foregoing and additional objects, as well as the advantages and novel features of this invention, will become apparent from the description which follows, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of a grease extraction ventilator, constructed in accordance with this invention, of the updraft type, with the stove, broiler or other cooking equipment, as well as the exit duct or flue, being shown in dot-dash lines;

FIG. 2 is a front elevation of the ventilator of FIG. 1;

FIG. 3 is an end elevation of the ventilator of FIG. 1;

FIG. 4 is a transverse vertical section, on an enlarged scale,'taken along line 44 of FIG. 2;

FIG. 5 is a transverse vertical section, on an enlarged scale, taken along line 55 of FIG. 2;

FIG. 6 is an enlarged detail of a portion of FIG. 4, as indicated, showing particularly a drain cube for the water bath;

FIG. 7 is an enlarged detail of a portion of FIG. 5, as indicated, but showing an adjustable baffle moved to a different position and also the contour of the water bath during use;

FIG. 8 is a laterally condensed vertical section, on an enlarged scale, taken along line 8-8 of FIG. 3;

FIG. 9 is a fragmentary vertical section taken along line 99 of FIG. 4, showing particularly a plenum damper and a cable which normally holds the damper open and is provided with a fuse link;

FIG. 10 is a front perspective view of a grease extraction ventilator forming another embodiment of this invention, of the downdraft type;

FIG. 11 is a front elevation of the ventilator of FIG. 10;

FIG. 12 is an end elevation of the ventilator of FIG. 10;

FIG. 13 is a transverse vertical section, on an enlarged scale, taken along line 13--l3 of FIG. 11;

FIG. 14 is a transverse vertical section, on an enlarged scale, taken along line 14l4 of FIG. 11;

FIG. 15 is an enlarged detail of a portion of FIG. 13, as indicated, showing particularly a drain cube and associated parts of the water bath;

FIG. 16 is an enlarged detail of a portion of FIG. 14, as indicated, but showing an adjustable baffle moved to a different position and also the contour of the water bath during use;

FIG. 17 is a condensed lateral section, on an enlarged scale, taken along line 17l7 of FIG. 12; and

FIG. 18 is a wiring diagram of an electrical control which may be used with the ventilator of either FIG. 1 or the ventilator of FIG. 10.

As illustrated in FIGS. 1-3, a ventilator V of this invention may be mounted in any suitable manner above cooking equipment E, such as a range, stove, broiler or the like, or a series of the same, with the side to side width of the ventilator corresponding to the width of the cooking equipment. The ventilator may be provided with a hook H having a shelf on the top thereof and a front, depending flange 11 thereof dis-- posed directly above and forwardly of the front edge of the cooking equipment E. The cooking equipment is normally provided with. a back plate 12 which extends above the cooking level of the cooking equipment E and is connected to the underside of the ventilator V at the rear edge thereof. A single side plate 13, as in FIG. 1, may form the end of both the ventilator V and the hood H, although the hood I-I may be furnished as a separate item of equipment, with a side plate 130 of the ventilator and a side plate 13b of the hood, as in FIG. 3, being separate but connected parts. A control box C is conveniently mounted on the shelf 10 of the hood I-I, although it may be placed in any suitable posi tion, and is conveniently provided with a light switch 14 and a wash switch 15. The light switch 14 is used to turn on and off a light, such as of the fluorescent type, which extends across the underside of the shelf 10 of the hood I-I, while the operations which ensue after activation of the wash switch 15 will be described later. In addition to side plate 13, the ventilator V is provided with a top plate 16, a front plate 17 having an opening over which is installed a removable access plate 18, and a back plate 19. Access plate 18 is utilized primarily for installation or repair, and thus normally remains fixed in position, even during cleaning. The top plate 16 is provided with a rectangular opening in which is mounted a hollow, rectangular duct 20 which connects with an outlet or exit duct D which leads to the flue of a chimney, and in which a suction fan of a conventional nature (not shown) is installed. Ordinarily, the suction fan is turned on at all times, except at certain times during the washing cycle, but is separately controlled.

The control box C may be provided with two compartments, in one of which the plumbing control valves are installed, as described later, and in the other of which the electrical controls are installed, as described later. Both the plumbing controls and the electrical controls are standard control equipment and thus are not shown, although a description of what they are and their preferred sequence of operation is given later.

In accordance with this invention, as more particularly illustrated in FIGS. 4 and 5, the ventilator of this invention is provided with an upright plate 22 having an arcuate curl 23 at the top and extending across the front of the ventilator at its lower edge, being connected to a bottom plate 24 and extending upwardly therefrom. Extending rearwardly and initially slightly downwardly from the lower edge of the front plate 17 is a fixed baffle 25 which continues rearwardly and downwardly as an arcuate portion 26, which begins at a position spaced above, but slightly rearwardly from, a curl 23 of the upright plate 22. Preferably, the radius of curvature of arcuate portion 26 of the baffle corresponds to the distance from the center of the arcuate curl 23, so as to form a channel of substantially constant width curving arcuately around the curl 23. The lower edge of arcuate portion 26 is disposed below but, of course, rearwardly of the curl 23, while an arcuate, adjustable baffle 27 having the same radius of curvature as fixed baffle 25, but a planar segment 28 at its lower edge, is attached, as by bolts 29, to the fixed baffle. The bolts 29 are inserted within vertical slots in the fixed baffle 25 and extend through holes in the adjustable baffle 27, with nuts welded on the back side of the adjustable baffle, so that the position of the adjustable baffle may be adjusted between an upper position in which the planar segment 28 abuts the lower end of arcuate portion 26 of the fixed baffle, and the position shown, in which the adjustable baffle is fully extended. Ordinarily, the distance between the upright plate 22 and the end of the planar segment 28 will be as shown in FIG. 7, i.e., approximately twice the minimum distance therebetween, the latter being shown in FIG. 5.

For each installation, the position of adjustable baffle I 27 may be changed, depending upon the normal water level, as hereinafter described, the total width of the ventilator and the cubic feet of air admitted, which are drawn through the ventilator by the suction fan, such as on the order of 250 cubic feet per minute for each lineal foot of the width of the ventilator. In general, a throat section of lesser cross sectional area is formed between the end of planar segment 28 and the rear of upright plate 22, so as to increase the velocity of the air flowing at this point, for a purpose described below, with the air flowing into the ventilator through an inlet formed between curl 23 and the underside. of baffle 25.

A water bath W having a normallevel indicated by the dotted line 30 of FIG. 6, and the upper contour during use, indicated by the full line 31 of FIG. 7, is maintained in the lower portion of the ventilator within the space determined by the bottom plate 24, the back plate 19 and the upright plate 22, as well as the

side plates

13 or 13a. The normal level of the water bath W, as in FIG. 6 is determined by the height of a drain cube 32 which has an open top and is provided with a drain pipe connection 33 which normally will extend through the rear wall 19, as shown, but alternatively may extend through the bottom wall 24, as indicated by the dotted line position 33a of FIG. 6. The open top of the drain cube 32 receives any overflow of the water bath, with the central position of the drain cube, as in FIG. 8, insuring that overflow water carrying grease and condensed vapor products will flow from each end of the water bath to the center, for substantially continuous removal of grease and condensed vapor products. A frontally concave, arcuate deflector plate 34 extends, as in FIG. 8, from each end of the ventilator to the area of the drain cube 32, along the lower rear of the water compartment, with deflector plate 34 having either essentially the same radius of curvature as the arcuate portion 26 and adjustable baffle 27, or a slightly greater radius of curvature. Deflector plate 34 is attached to the bottom wall 24 by a series of lower tabs 35, as in FIGS. 7 and 8, and to the rear wall 19 by a correspondingly spaced series of upper tabs 36 of FIG. 7, in order to provide a space between the lower edge of deflector plate 34 and the bottom wall 24, as well as between the upper edge of deflector plate 34 and the rear wall 19. The cross sectional area occupied by the

tabs

35 and 36 is such as to offer no significant impediment to the flow of water beneath the lower edge of deflector plate 34, as well as down and behind the upper edge of deflector plate 34. Access to the drain is through removable plate 21, covering a hole in upright plate 22, as in FIGS. 2, 4 and 5. 1

In further accordance with this invention, as the air stream, whose velocity is increased by the throat section between the end of planar segment 28 and the upright plate 22, engages the water bath W, it will push the water up against the deflector plate 34, as well as agitating and whipping the surface of the water,

thereby churning the water quite violently and causing tongues of water to move up into the air stream, as indicated in FIG. 7, to remove grease from the air stream, as well as condensed vapor products. Thus, the entire body of water W is forced up against the deflector plate 34.and will overflow the upper edge of plate 34, to fall behind the plate and carry with it retained grease and condensed vapor products. The contour 31 of the water will become on the order of that shown in FIG. 7. although the water will tend to surge upwardly and downwardly as well, during the agitation by the air. Additional water vapor or droplets will also enter the air stream and condense or coagulate, to be thrown out when passing around the upper end of a downwardly concave, essentially arcuate air deflector plate 38 which extends from generally opposite the lower edge of fixed baffle 25, to a point above the fixed baffle 25, as in FIGS. 4 and 5. Thus, water droplets containing condensed vapors or grease which has not been removed by the previous action of the water bath, will tend to be thrown out against the front plate 17, to drip back downwardly into the water bath along baffle 25. The upper edge of plate 38 is maintained in position by a forwardly extending bracket plate 39 which is attached along its front edge to the top of a planar seg-- ment 40 of deflector plate 38 and along the rear edge of rear wall 19 by a channel structure 41, which performs an additional function described later. It will be noted that the downwardly slanting planar segment 40, along the upper edge of deflector plate 38 provides a throat section which causes the velocity of air above fixed baffle 25 to increase and causes the water droplets to separate when the air impinges against front wall 17, for subsequent return to the water bath by flowing along the top of baffle 25, which is coated by such flow.

The rear, lower edge of air deflector baffle 38 is secured to, but spaced slightly from, the back wall 19 by a spacing block 42 which leaves a space at each end so that the water feed for replenishing the water bath, due to evaporation or overflow into drain cube 32, may be introduced at each end of the water bath, as in a manner hereinafter described. Thus, the makeup water feed, as on the order of A gallons per hour per lineal foot of width, may be through a pipe 43 which extends rearwardly from the front of the ventilator, as in FIG. 5, adjacent the right end thereof, as in FIG. 8, and then downwardly through the bracket plate 39 of FIG. 4. Water will flow from pipe 43 through the space at that end of block 42 and also on top of block 42 to the space at the opposite end of the block.

Since the height of drain cube 32 is such that there is insufficient space below the deflector plate 34 to accommodate the drain cube, a relatively short cover 44 is provided, which is contoured to fit over the drain cube 32, as in FIG. 4, but is provided with end walls 45 which extend downwardly to below deflector plate 34 and a lower flange 46 which is in alignment with the lower edge of deflector plate 34. Cover 44 also extends to the rear wall 19, for attachment thereto by bolts, as shown, extending through a rear, upwardly extending flange 47 of the cover.

After passage between segment 40 and front plate 17, the air drawn by the suction fan will pass upwardly into a plenum chamber P of FIGS. 5 and 8, in which the air will move from each end toward the center for discharge through duct and thence into duct D for exhaust to the atmosphere.

For cleaning purposes, as in the manner described later, a hot water feed pipe 49 extends along the rear wall 19 within the channel structure 41 and is provided with a series of spaced sprinkler type heads or nozzles 50, for spraying hot water toward the front plate 17 and the underside of top plate 16, which will tend to be deflected onto the fixed baffle 25 and flow downwardly along the same, and also be deflected against the air deflector plate 38. This hot water will also flow downwardly onto the cover 44 and water deflector plate 34 above the water bath.

For safety purposes, in order to obstruct the passage of flames into the duct D, should a fire occur, a safety damper 51 is installed within the duct D, just above the plenum chamber P. The damper 51 may be merely a plate attached, as by U-bolts, to a pivot rod 52, the ends of which are mounted in bearings 53, shown in FIG. 3, installed in the opposite end walls of the duct. The damper 51 is provided with a weight 54, as in FIG. 4, which extends the full length of one edge of the damper, so that when released from the upright position of FIG. 4, the damper will immediately swing to a closed position, shown in dotted lines in FIG. 4, with the weighted edge of the damper moving downwardly against an angle 55 attached to the rear wall of the duct 20, and the opposite edge of the damper engaging an angle 56 attached to the front wall of the duct. In order to retain the damper in the open position, shown in full lines in FIG. 4, a fuse link cable extends around a pair of hooks 57 attached to the damper adjacent each end and adjacent the edge opposite the weight, as in FIGS. 4 and 9. A pair of hooks 58 are attached to the front wall 19 of the plenum chamber P, so as to be spaced apart farther than the hooks 57, with a cable 59 extending around one each of

hooks

57 and 58. The cables 59 are connected together between the hooks 58 by a fuse link 60, which is of a conventional material which will melt at a predetermined fire hazard temperature, in order to release the cables and permit the damper to close. Between hooks 57, the cables are connected by a turnbuckle 61, so that the cables may be loosened, for placement around hooks 57 and 58, and then tightened to hold the damper in open position. Normally, of course, the damper 51 will stay in its open position, perhaps for months at a time. However, the access plate 18 may be removed to replace the fuse link and reset the cable, in the event of fire from which the flames have melted the fuse link. Normally, of course, even in the event of a fire on the cooking equipment, flames sucked up into the ventilator will normally be extinguished by passage along or through the churning water bath W.

In cleaning the ventilator of this invention, the operator is requiredto clean manually only the front of upright plate 22 and its curl 23, the underside of fixed baffle 25 and its arcuate portion 26, and the outside of the adjustable baffle 27. Also, the operator may wish to reach over the curl 23 and clean the inside of plate 22 above the water bath W. All other surfaces are cleaned by a non-manual cleaning procedure, such as follows. First, the operator dumps a supply of detergent or other cleaning liquid into the water bath, then permits the suction fan to draw the water containing the detergent solution up into the ventilator through splashing and agitation of the water. As will be evident,the cleaning solution carried upwardly by the air stream will reach all of the surfaces which are reached by splashed water and water droplets during normal operation. After the detergent solution has been splashed about on the inside of the ventilator, as for 30 minutes to 1 hour, the

, operator pushes the wash switch button 15 of FIG. 1,

which causes hot water to be supplied through pipe 43 at a rate several times that of the normal makeup flow, such as on the order of 4 to 8 gallons per minute, for a period of two minutes. This hot water replaces the cold water in the water bath W, and the air flow is continued, so that the air will splash hot water up against the underside of baffle 38 and carry hot water droplets along the rear of section 26 onto the top of fixed baffle 25. When the wash switch 15 is first pushed, the cold water metering valve, which normally supplies cold water for normal use, is shut off, and a hot water metering valve, which is set to produce the above considerably higher rate or flow, as indicated, is turned on. While water is merely being fed into the water bath to replace the cold water therein, the suction fan may continue running. Next, the operator turns off the suction fan and pushes the wash switch 15 a second time, to supply hot water through a third valve to pipe 49 and to nozzles 50, which will spray toward the front plate 17, up against the top plate 16, and also into the duct section 20. In addition, water splashing from front plate 17 and top plate 16 will tend not only to splash against rear plate 19, but also run downwardly along fixed baffle 25 and return to the water bath. Of course, during this operation, excess water in the water bath will tend to be drained by overflow into drain cube 32. As noted above, when the plenum wash nozzles are turned on, the suction fan should be turned off. Thus, an electrical circuit which controls, through relays, the operation of this valve is interconnected with the fan control circuit, as described later, so that the hot water valve for pipe 49 cannot be turned on while the fan is running. As will be evident, the detergent and initial hot water washing operation can be carried out while cooking continues. However, when the suction fan is turned off for plenum washing, cooking should be discontinued.

As illustrated in FIGS. 10-12, a ventilator V of this invention, of the downdraft type, may be mounted in any suitable manner above cooking equipment E of FIG. 12, such as a range, stove, broiler or the like, or a series of the same, with the side to side width of the ventilator corresponding to the width of the cooking equipment. The ventilator may be provided with a hood H disposed above the cooking equipment E and having a shelf 10 on the top thereof and a front, depending flange 11'. A single side plate may form the end of both the ventilator V and the hood H, although the hood H may be furnished as a separate item of equipment, with a side plate 130 of the ventilator and a side plate 13b of the hood, as in FIGS. 10 and 12 being separate but connected parts. A control box C is conveniently mounted under the ventilator, although it may be placed in any suitable position, while a housing 62 for a wash switch 15 may be mounted on the shelf of the hood, at one end. A light switch (not shown) may be used to turn on and off a light, such as of the fluorescent type, which extends across the underside of the shelf 10 of the hood. The ventilator V is provided with a top panel 16' having depending flanges fitting over the end plates, an upper front plate 17 of FIG. 14 and a back plate 19' of FIGS. 13 and 14. End plate 130 and back plate 19 extend down to a bottom plate 63 of FIGS. 14 and 17, having a rectangular opening located centrally thereof for a duct connector 20 which is open at the top and at one end for connection, at a rectangular flange 64, with an outlet or exit duct D which leads beneath and then upwardly at one end of the ventilator to the flue of a chimney. A suction fan of a conventional nature (not shown) is installed at an appropriate position in duct D. As before, the suction fan is turned on at all times, except at certain times during the washing cycle, although it may also be separately controlled. A drain pipe 65 is connected to the opposite end of duct connector 20', adjacent the lower edge thereof.

The control box C may be provided with two compartments, in one of which the plumbing control valves are installed, and in the other of which electrical controls are installed, except the wash switch 15. As before, both the plumbing controls and the electrical controls are standard equipment.

A lower front plate 66, as in FIGS. 13 and 14, extends upwardly from bottom plate 63 to the lower edge of an upright plate 22, having an arcuate curl 23 at the top and extending across the front of the ventilator in spaced relation to front plate 17. At its lower edge, plate 22 is connected to a bottom plate 24 of a water chamber. As before, extending rearwardly and initially slightly downwardly from the lower edge of the front plate 17, is a baffle. 25 which continues rearwardly and downwardly as an arcuate portion 26. An arcuate, adjustable baffle 27, having the same radius of curvature as fixed baffle 25', but a planar segment 28 at its lower edge, is attached, as by bolts 29, to the fixed baffle. If desired, the bolts 29 may be inserted within holes in the fixed baffle 25 and extend through vertical slots in the adjustable baffle 27. For each installation, as indicated previously, the position of adjustable baffle 27 is essentially fixed, depending upon the normal water level, as hereinafter described, and the total width of the ventilator and the cubic feet of air admitted, which are drawn through the ventilator by the suction fan. In general, a throat section of lesser cross sectional area is formed between the end of planar segment 28 and the rear of upright plate 22, so as to increase the velocity of the air flowing at this point, for a purpose described below.

A water bath W having a normal level indicated by the dotted line 30 of FIG. 15, and an upper contour during use, indicated by the full line 31 of FIG. 16, is maintained in the lower portion of the water space determined by the bottom plate 24, the upright plate 22, side plates 13a and a rear plate 67 of the water chamber. Plate 67 extends upwardly, then forwardly and upwardly in approximately a half circle, similarly to plate 38 of FIGS. 4 and 5. The normal level of the water bath W, as in FIG. 15, is determined by the height of a drain cube 32 which has an open top and connects with a drain duct 68, which, as in FIG. 13, extends on the underside of bottom plate 24' and then downwardly along plate 66 and thefront wall of duct 20', so that water overflowing into the drain cube will flow into the bottom of duct 20' and out drain pipe 65. As before, a frontally concave, arcuate deflector plate 34 extends, as in FIG. 17, from each end of the ventilator to the area of the drain cube 32, along the lower rear of the water compartment, with deflector plate 34 being attached, as before, to the bottom wall 24' by a series of lower tabs 35, as in FIG. 16, and by a correspondingly spaced series of upper tabs 36 to back plate 67, which is maintained in position by attachment to side plates 13a, or also by struts or brackets corresponding to brackets 39 of FIGS. 4 and 5.

As before, the air stream pushes the water up against the deflector plate 34', as well as agitating and whipping the surface of the water, to remove grease from the air stream, as well as condensed vapor products. Thus, the entire body of water W is forced by against the deflector plate 34 and will overflow the upper edge of plate 34', to fall behind the plate and carry with it the retained grease and condensed vapor products. The contour 31 of the water will become on the order of that shown in FIG. 16, although the water will tend to surge upwardly and downwardly as well during the agitation by the air. Additional water vapor or droplets will also enter the air stream and condense or coagulate on the underside of the plate 67, as well as being removed when thrown against the front plate 17 due to the velocity imparted by a throat section, such as formed by a downwardly inclined, planar segment 40 at the upper end of plate 67. As before, a relatively short cover 44 is provided for drain cube 32, being contoured to fit over the drain cube 32 and provided with end walls 45, which extend downwardly to or below plate 34, a lower flange 46', which is in alignment with the lower edge of deflector 34, and a flange 47' for attachment to the plate 67 by bolts, as shown.

The water feed for replenishing the water bath, due to evaporation or overflow into drain cube 32, may be introduced at each end of the ventilator, as through a pair of pipes 43 which extend rearwardly from the front of the ventilator, into the space between baffle 25 and plate 67. Pipes 43 are supplied by a tube 69 which extends upwardly from control box C, as in FIGS. 14 and 17.

For cleaning purposes, as in the manner described later, a hot water feed pipe 49' extends along the upper rear corner of the ventilator, as in FIGS. 14 and 17, and is provided with a series of spaced sprinkler typeheads or nozzles 50, for spraying hot water onto the rear of baffle plate 67 and the inside of rear wall 19, as well as into the lower plenum space F, for drainage from duct connector Another hot water pipe 70 having a spaced series of nozzles 50 extends along the upper front corner of the ventilator, as in FIG. 14, for spraying hot water against the inside of plate 17 and onto baffle for deflection against the front side of plate 67, with drainage along plate 67 and baffle 25 into the water chamber. Hot water pipes 49 and 70 are supplied by a tube 71 extending upwardly fron control box C, as in FIGS. 14 and 17, to rear pipe 49' and also across the top of the ventilator to front pipe 70.

For safety purposes, in order to obstruct the passage of flames into the duct D, should a fire occur, a safety damper 51 is installed within the duct connector 20' and the lower plenum chamber P. As before, damper 51 may be merely a plate attached, as by U-bolts, to a pivot rod 52, the ends of which are mounted in bearings (not shown) installed in the opposite end walls of the duct connector 20. The damper 51, as before, is provided with a weight 54, which extends the full length of one edge of the damper, so that when released from the upright position of FIG. 13, the damper will immediately swing to a closed position. Thus, the weighted edge of the damper will move downwardly against an angle 55 attached to an appropriate wall of the duct connector 20, and the opposite edge of the damper will engage an angle 56' attached to the opposite wall of the duct connector. The unweighted edge of the damper 51 is provided with a cutout to clear the drain duct 68. In order to retain the damper in the open position, as before, a cable extends around a pair of hooks 57 attached to the damper and a pair of hooks 58 attached to the near wall of the duct connector 20. As before, a fuse link and a turnbuckle are interposed in the cable. A drain access plate 21 may be installed over an opening in front plate 66, while an access plate 18' may be installed over an opening in the rear wall of duct connector 20', as in FIG. 13, for the same purpose as access plate 18 of FIG. 1. Normally, of course, even in the event of a fire on the cooking equipment, any flames sucked up into the ventilator will tend to be extinguished by passage along or through the churning water bath W.

An electrical control system which may be used with either the ventilator of FIGS. l-9 or the ventilator of FIGS. 10-17 is illustrated in FIG. 18, being interconnected with the duct fan previously described. Thus, a fan motor 73 may be controlled by a switch S which includes

contacts

74 and 74, being supplied with current from power leads 75 and 76 in a three-wire'system which includes a neutral line 77. In FIG. 18, the connection of the neutral line 77 to the fan motor 73 is not shown, for clarity of illustration; In addition to the wash switch 15, the electrical controls include a relay R, a timing relay T and three solenoid operated water control valves, including a valve 78 through which cold water, as indicated, is supplied to the makeup pipe 43 of FIGS. 4, 5 and 8 or the makeup tube 43 of FIGS. 13 and 14. The valve 78 is adjusted to produce a relatively small rate of flow when open, as described previously. Another solenoid controlled valve 79 supplies hot water, as indicated and as from the normal hot water tap line, through the hot water feed pipe 49, to the

pipe

43 or 43, being adjusted to produce a higher rate of flow, for displacement of the cold water in the water bath W or W by hot water, following addition of detergent to the cold water bath and normal agitation of the water bath by the air for a short period of time, as indicated. Another solenoid controlled water valve 80 also supplies hot water, as indicated, but at a much higher rate of flow, and to the plenum wash supply pipe 49 of FIGS. 4, 5 and 8 or 49 of FIGS. 13, 14 and 17. In general, the electrical controls are such that the light switch 14 may be turned on at all times, the cold water solenoid valve 78 and the hot water solenoid valve 79 may turned on only when the fan motor 73 is running, while the plenum wash solenoid hot water valve 80 may be turned on only when the fan motor 73 is turned off. Thus, a hot" wire 81 is connected to the fan motor lead 76 and extends to the relay R, with afuse 82 being interposed therein, while a branch 83 thereof extends to the light switch 14. Return wire 84 from the light is connected to neutral lead 77.

. A wire 85 is also connected to the same fan motor lead 76, but beyond switch contact 74, so that current will be supplied through wire 85 only if the fan motor is turned on. Wire 85 extends to the terminal of a switch 86 of timing relay T, with a second fuse 82 interposed therein. From the normally closed contact of switch 86, a wire 87 extends to the coil 88 of solenoid valve 78, the opposite side of coil 88 being connected to neutral line 77, as shown. Thus, when the duct fan is turned on, the solenoid valve 78 will be automatically opened and begin supplying cold makeup water to the water bath in the ventilator. A branch wire 89 leads from wire 85 to one end of the coil 90 of relay R and thence to a switch 91 of the relay, while a wire 92 leads from the opposite end of the coil to the neutral lead 77. When the fan motor is turned on, the coil 90 of relay R will be energized, moving switch 91 from the normally closed contact shown to its normally open contact. A switch 93 of relay R, to which wire 81 extends, will also be moved from its normally closed .contact to its normally open contact. Thus, the

switches 91 and 93 will be moved to the dotted positions shown, when the coil of relay R is energized. It will be noted that, when moved to its normally open contact, switch 91 will permit current to be supplied through a wire 94 to a contact 95 of wash switch 15, which, however, remains open. Also, when switch 93 is in engagement with its normally closed contact, it will supply current through a wire 96 to another contact 97 of switch 15, while a branch wire 98 will also supply current to a switch 99 of timing relay T. However, no flow of current can take place because switch is open, and there is no wire connected to the normally closed contact of switch 99.

When the cleaning operations are begun and the detergent is poured by the operator into the water bath W or W, in the respective form of ventilator shown, after agitation of the water bath and circulation of the water containing detergent up into the ventilator by the air, as for about 30 minutes, the operator closes the wash switch 15, to start the replacement of the cold water by hot water. Thus, when switch 15 is closed, current will be supplied through wire 94 (switch 91 then being in the dotted position) to contact 95 and its opposing contact 95' and through a wire 100 to a time delay coil 101 of relay T. When coil 101 is energized, both switch 86 and switch 99 will be moved from its respective normally closed contact to its normally open contact. When this occurs, the solenoid 88 of valve 78 will be deenergized, and the solenoid 88' of valve 79 will be energized, through a wire 102 which leads thereto from the normally open contact of switch 86. Although switch 99 will also be 'moved to its normally open contact, which is connected by a wire 103 with the solenoid coil 88" of valve 80, no current will be supplied to coil 88", since switch 93 of relay R will be moved to its dotted position, when the fan motor 73 is turned on. The time delay of relay T is set for a predetermined time, such as 2 or 3 minutes, in order to permit the cold water in the water bath to be replaced by hot water, after which the time delay relay is automatically deenergized, with

switches

86 and 99 returning to their normally closed positions. Then, the operator turns the fan motor 73 off, which will open the

switch contacts

74 and 74. This means that current is no longer supplied through wire 85 to coil 90 of relay R, which will also be deenergized thereby, causing

switches

91 and 93 to return to their respective normally closed contacts. in addition, the cessation of current flow through wire 85 will cause coil 88 of valve 78 to remain deenergized, even though switch 86 of relay T returns to its normally closed contact. However, when switch 93 of relay R returns to its normally closed contact, the wire 81 connected to the motor lead 76 ahead of contact 75 will supply current through switch 93 and wire 96 to contact 97 of switch 15 and also through branch wire 98 to switch 99. Thus, after the fan is turned off and switch 15 is moved to closed position a second time, time delay relay coil 101 will again be energized, thereby moving switch 99 to its normally open contact and supplying current through wire 103 to coil 88" of solenoid valve 80. This will cause hot water to be supplied to the plenum washing supply pipe 49 for the predetermined washing period, again determined by the time cycle of relay T, at the end of which the time delay coil 101 will be automatically deenergized and the

switches

86 and 99 returned to their normal positions. The operator may then turn on the fan motor 73 which causes, through closing of the fan motor switch contact 75, current to be again supplied through wire 85, switch 86 and wire 87 to coil 88 of solenoid valve 78, thereby turning on the cold water makeup water and normal operation resumed.

It will be noted that the water droplets thrown out of the air stream by impinging against front wall 17 of FIG. 5 or front wall 17 of FIG. 14 will drain downwardly on the top side of fixed baffle 25 or 25', respectively. This water, as well as water splashed onto the top side of the fixed

baffle

25 or 25, maintains the underside of the baffle at a lower temperature, thereby minimizing the amount of grease or other cooking residue which will be burned or otherwise transformed by the heat from the cooking equipment and be more difficult to clean off. As a result, the ventilator of this invention will require less labor to maintain, in a clean condition, the underside of a baffle above the cooking area.

Although certain preferred embodiments of this invention have been illustrated and described, it will be evident that other embodiments may exist and various changes made without departing from the spirit and scope of this invention.

What is claimed is:

l. A grease extraction ventilator-connectable to a duct having means for producing flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air stream normally containing products of cooking in an area adjacent said entrance space, such as smokeparticles, grease and the like, said ventilator comprising a housing having:

a. a chamber below said front entrance space and having a front wall;

b. means for supplying water to said chamber; and

c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream, including baffle means spaced from said front wall and forming the rear wall of said front entrance space, said baffle means extending rearwardly and downwardly to a point below the upper edge of said front wall and then forwardly toward said front wall.

2. A grease extraction ventilator as defined in claim 1, including:

means for separating water moved by said air stream in the direction of flow of said air stream; and means for removing said separated water carrying grease and the like from said chamber.

3. A grease extraction ventilator as defined in claim 1, wherein said baffle means includes:

an inlet baffle extending from a position forwardly and above the front edge of said chamber, then curving rearwardly and downwardly to an adjustable baffie; and

said adjustable baffie including an arcuate rear portion and a planar front portion extending toward said front wall of said chamber.

4. A grease extraction ventilator as defined in claim 3, wherein:

said upper edge of said chamber is provided with an arcuate curl generally concentric with the curve of said inlet baffle.

5. A grease extraction ventilator connectable to a duct having means for producing flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air stream normally containing products of cooking in an area adjacent said entrance space, such as smoke particles, grease and the like, 'said ventilator comprising a housing having:

a. a chamber below said front entrance space;

b. means for supplying water to said chamber;

c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream, said means including an inlet baffie extending from a position forwardly and above the front edge of said chamber, then curving rearwardly and downwardly to an adjustable baffle, said entrance space being formed between the underside of said inlet baffle and the upper edge of said chamber;

d. said adjustable baffle including an arcuate rear portion and a planar front portion; and

e. a deflector baffle extending from the rear edge of said chamber above the water level therein and upwardly and forwardly in spaced relation to said inlet baffie to form a generally upwardly disposed passage above said chamber.

6. A grease extraction ventilator as defined in claim 5, wherein:

said means for supplying water to said water chamber is adapted to feed water into the space between the rear side of said deflector baffle and a wall which extends upwardly from the rear wall of said chamber.

7. A grease extraction ventilator as defined in claim 5, wherein:

said means for supplying water to said chamber is adapted to feed water between the top of said inlet baffle and the underside of said deflector baffle.

8. A grease extraction ventilator as defined in claim 5, including:

a plenum chamber having a duct connection, said air stream flowing around the upper edge of said deflector baffie and into said plenum chamber;

means for supplying heated water to displace water in said chamber; and

additional means for supplying heated water and directing such heated water into the space between said deflector baffle and the top of said inlet baffie and also into said plenum chamber.

9. A grease extraction ventilator as defined in claim 5, including:

a plenum chamber above said deflector baffle and provided with a connection for said duct.

10. A grease extraction ventilator as defined in claim 5, including:

a passage extending from above said deflector baffie and downwardly and rearwardly of said water chamber; and

a plenum chamber below said water chamber, said plenum chamber having a connection for said duct.

11. A grease extraction ventilator as defined in claim 9, including:

a damper adapted to close the opening at said duct connection;

means for urging said damper toward its closed positron;

means for holding said damper in its open position;

and

temperature responsive means associated with said holding means and adapted to permit said damper to be closed in response to a predetermined temperature at said temperature responsive means.

12. A grease extraction ventilator as defined in claim 10, including:

a damper adapted to close the opening at said duct connection;

means for urging said damper toward its closed position;

means for holding said damper in its open position;

and

13. A grease extraction ventilator as defined in claim 5, wherein:

the upper end of said deflector baffle is provided with a downwardly extending planar portion.

14. A grease extraction ventilator connectable to a duct having means for producing :flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air stream normally containing products of cooking in an area adjacent said entrance space, such as smoke particles, grease and the like, said ventilator comprising a housing having:

a. a chamber below said front entrance space;

b. means for supplying water to said chamber;

c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream; and

d. means for separating water moved by said air stream in the direction of flow of said air stream, including a plate curving upwardly in substantially the rear portion of said chamber, the upper edge of said plate being spaced from the rear wall of said chamber for overflow of water driven upwardly along said plate by said air stream and the lower edge of said plate being spaced above the bottom of said chamber for the flow of water from behind said plate to a position forwardly of said plate.

15. A grease extraction ventilator as defined in claim 14, including:

overflow means behind and below the upper edge of said plate to permit water overflowing said plate and carrying with it grease and the like to be removed from substantially the top of said water behind said plate.

Claims

1. A grease extraction ventilator connectable to a duct having means for producing flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air streaM normally containing products of cooking in an area adjacent said entrance space, such as smoke particles, grease and the like, said ventilator comprising a housing having: a. a chamber below said front entrance space and having a front wall; b. means for supplying water to said chamber; and c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream, including baffle means spaced from said front wall and forming the rear wall of said front entrance space, said baffle means extending rearwardly and downwardly to a point below the upper edge of said front wall and then forwardly toward said front wall.

2. A grease extraction ventilator as defined in claim 1, including: means for separating water moved by said air stream in the direction of flow of said air stream; and means for removing said separated water carrying grease and the like from said chamber.

3. A grease extraction ventilator as defined in claim 1, wherein said baffle means includes: an inlet baffle extending from a position forwardly and above the front edge of said chamber, then curving rearwardly and downwardly to an adjustable baffle; and said adjustable baffle including an arcuate rear portion and a planar front portion extending toward said front wall of said chamber.

4. A grease extraction ventilator as defined in claim 3, wherein: said upper edge of said chamber is provided with an arcuate curl generally concentric with the curve of said inlet baffle.

5. A grease extraction ventilator connectable to a duct having means for producing flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air stream normally containing products of cooking in an area adjacent said entrance space, such as smoke particles, grease and the like, said ventilator comprising a housing having: a. a chamber below said front entrance space; b. means for supplying water to said chamber; c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream, said means including an inlet baffle extending from a position forwardly and above the front edge of said chamber, then curving rearwardly and downwardly to an adjustable baffle, said entrance space being formed between the underside of said inlet baffle and the upper edge of said chamber; d. said adjustable baffle including an arcuate rear portion and a planar front portion; and e. a deflector baffle extending from the rear edge of said chamber above the water level therein and upwardly and forwardly in spaced relation to said inlet baffle to form a generally upwardly disposed passage above said chamber.

6. A grease extraction ventilator as defined in claim 5, wherein: said means for supplying water to said water chamber is adapted to feed water into the space between the rear side of said deflector baffle and a wall which extends upwardly from the rear wall of said chamber.

7. A grease extraction ventilator as defined in claim 5, wherein: said means for supplying water to said chamber is adapted to feed water between the top of said inlet baffle and the underside of said deflector baffle.

8. A grease extraction ventilator as defined in claim 5, including: a plenum chamber having a duct connection, said air stream flowing around the upper edge of said deflector baffle and into said plenum chamber; means for supplying heated water to displace water in said chamber; and additional means for supplying heated water and directing such heated water into the space between said deflector baffle and the top of said inlet baffle and also into said plenum chamber.

9. A grease extraction ventilator as defined in claim 5, including: a plenum chamber above said deflector baffle and provided with a connection for said duct.

10. A grease extraction ventilator as defined in claim 5, including: a passage extending from above said deflector baffle and downwardly and rearwardly of said water chamber; and a plenum chamber below said water chamber, said plenum chamber having a connection for said duct.

11. A grease extraction ventilator as defined in claim 9, including: a damper adapted to close the opening at said duct connection; means for urging said damper toward its closed position; means for holding said damper in its open position; and temperature responsive means associated with said holding means and adapted to permit said damper to be closed in response to a predetermined temperature at said temperature responsive means.

12. A grease extraction ventilator as defined in claim 10, including: a damper adapted to close the opening at said duct connection; means for urging said damper toward its closed position; means for holding said damper in its open position; and temperature responsive means associated with said holding means and adapted to permit said damper to be closed in response to a predetermined temperature at said temperature responsive means.

13. A grease extraction ventilator as defined in claim 5, wherein: the upper end of said deflector baffle is provided with a downwardly extending planar portion.

14. A grease extraction ventilator connectable to a duct having means for producing flow of an air stream into a front entrance space of said ventilator, through said ventilator and from said ventilator into said duct, said air stream normally containing products of cooking in an area adjacent said entrance space, such as smoke particles, grease and the like, said ventilator comprising a housing having: a. a chamber below said front entrance space; b. means for supplying water to said chamber; c. means for causing said air stream to engage and agitate said water, thereby causing said water and water vapor produced by said agitation to tend to remove smoke particles, grease and the like from said air stream; and d. means for separating water moved by said air stream in the direction of flow of said air stream, including a plate curving upwardly in substantially the rear portion of said chamber, the upper edge of said plate being spaced from the rear wall of said chamber for overflow of water driven upwardly along said plate by said air stream and the lower edge of said plate being spaced above the bottom of said chamber for the flow of water from behind said plate to a position forwardly of said plate.

15. A grease extraction ventilator as defined in claim 14, including: overflow means behind and below the upper edge of said plate to permit water overflowing said plate and carrying with it grease and the like to be removed from substantially the top of said water behind said plate.