US 2868108 A
Description (OCR text may contain errors)
Jan.'13, 1959 u. K. PETERSEN VENTILATOR 2 Sheets-Sheet 1 Filed June 9, 1955 INVENTOR. (/M/J I. iriifi/v /W J W Jan; 13, 1959 Filed June 9, 1955 u. K. PETERSEN VENTILATOR 2 Sheets-Sheet 2 ava-2 I VENTILATOR" Ulric K. Petersen, Sonora, Calif.
Application June 9, 1955, Serial N 0. 514,146
1 Claim. (Cl. 98,,115)
The invention relates to improvements in devices for ventilating restaurant ranges.-
Heretofore, the large majority of, if not all, restaurant range ventilators have been custom built, and have been not only expensive but cumbersome to install, The customary ventilators, furthermore, have been diflicult to clean. Ventilators which are difiicult to clean are frequently not given the attention demanded by safety requirements of the municipality in which the ranges are located, and, as a consequence, violations of local ordinances are often to be found. Furthermore, and particularly if periodic cleaning is not performed, grease fires are acommonoccurrence in ventilators-of the kinds presently used.
his therefore an object of the invention to provide a range ventilator which is inexpensive to manufacture and install as well as requiring a minimum of upkeep expense.
It is another object of'theinventio'n toprovide a range ventilator which can be easily shipped in disassembled form and assembled on the job with a minimum of hand tools and by labor which does not require any special training or skill.
It is a further object of the invention to provide a ventilator which needs no adaptation or affixing to-the range but instead is a complete integral unit in itself capable of being installed and operated without being secured to the range.
It is yet another object of the-invention to provide a range ventilator which is especially adapted to being fabricated and installed in modulator lengths to fit a great variety of range sizesand types.
his a still further object of the invention to provide a ventilator which is capable notonly of exhausting or ventilating the oven portion of a range but which also serves to exhaust the hot fumes, odors and grease arising from the burner portion of a range.
It is yet another object of the invention to provide a range ventilator which is capable of condensing or congealing grease vapor and particles in the fumes generated byl the operation of a range and which, thus, substantially reduces the possibility of a grease or fiash fire.
It is yet a further object of the invention to provide a range ventilator which can not only be cleaned easily but which can be inspectedfor the presence of grease and other foreign material which gathers in range ventilators of the kind used in restaurants and other similar establishments.
It is yet another object of the invention to provide aventilator which can easily be adapted to handle the discharge of gases and fumes from any heat and fume generating source, such as a forge, chemical hood, etc.
It is yet another object of the invention to provide a generally improved ventilator.
Other objects, together with the foregoing, are attained in the embodiment described below and shown in the accompanying figures inwhich Figure l is a perspective of a ventilator, portions of- United States Patent the structure being broken away to show the construction, placement and co-operation of the interior members.
Figure 2 is a vertical sectional view from the left-hand side of the ventilator shown in Figure 1.
While the ventilator of my invention'is susceptible of numerous physical embodiments depending upon the particular environmental situation to be met, a considerable number of the herein shown and described ventilators have been made and installed and have performed in an eminently satisfactory fashion.
A typical restaurant range 6 is generally rectangular in. shape and often comprises a range top 7 provided with the customary burners 8 and a griddle 9. Within the interior of the range and below the burners and griddle is a pair of ovens 11 customarily vented either by a pipe leading rearwardly out of the oven and upward- 1y, or, as in the range shown, directly through the rear upper surface of the range as by an oven vent pipe 12. The effiuent gases from the oven are frequently at a temperature of 500 to 550 F. and comprise not only heated air and steam but often the products of broiling and other cooking processes and which frequently include considerable amounts of grease vapor and grease in the form of minute globules. Furthermore, owing to the cooking processes which are carried out. on the burners and griddle, considerable quantities of gases, such as heated air, and steam as well as grease and odors arising from the top of the range must be disposed of.
Since the ventilator of my invention is not afiixed to the range, it can be erected at a location nearby the range and moved into position over the range at a convenient time and in a convenient fashion. The ventilator frame comprises a pair of end plates 16 each conveniently fabricated from a pair of spaced parallel sheets 17 of material such as galvanized iron or aluminum, the margins of the sheets 17 being covered by an edge plate 18 to form between the sheets a dead air space 19 serving further to insulate the ends 21 of the oven from the kitchen working area. The end plates 16 are spaced from the adjacent oven ends 21, the plates and oven ends defining a vertical passageway 20 through which cool air from the floor flows upwardly and rearwardly. The bottom surface of the plates 16 are each provided with a suitable pairof adjustable feet 15 providing a space allowing laterally inward and upward flow of air from the floor.
Mounted in suitable fashion on the vertical rear edges of the end plates 16 is a vertical back plate 22 extending upwardly from a bottom edge 23, located two or three inches below the elevation of the range upper plate 7,' and terminating at its upper edge 24 in a peaked outline defining a triangular portion 25. A similarly configured triangular plate 26 is spaced forwardly from the portion 25 and spanning the sloping upper edges is a pair of cap plates 27 pierced in a central location to receive an exhaust stack 28, or pipe. If necessary to install the ventilator over a range in a kitchen not permitting of a central stack location, the stack will serve in an equally satisfactory fashion if displaced to the right or to the left in the ventilator hood shown in Figure 1, the members 25, 26 and 27 being suitably altered to conform to the desired stack location.
The hood generally designated by the numeral 30 also comprises in additionto the members 25, 26 and 27, a generally horizontal plate 31 having its rearward edge secured to the bottom of the plate 26 and its forward edge crimped to accept a corresponding or mating crimped portion 32 of a facade plate 33 depending fromv the plate 31 in a vertical fashion. The facade plate 33 terminates at its lower edge in an inwardly and upwardly crimped portion 34 adapted to receive and support a corresponding offset bracket 36 mounted on the forward wall of a grease collecting pan 37 or congealing member, the pan being supported by a pair of brackets 38 mounted oneach of the end plates 16.
The triangular portion 25 of the back plate, the triangular front plate 26, the cap plates 27, the plate 31, the facade plate 33, the bracket 36, and the grease pan 37 define a transversely elongated chamber 41 in which the pressure is reduced to a value below atmospheric by a fan 42, or blower in the stack.
The pan 37, however, serves not only partially to enclose the hood 30 so as to create the vacuum chamber 41 but also serves as a condenser or congealer for the grease particles which are carried upwardly in vapor or minute globular form with the products of combustion and cooking. The rear wall 46 of the grease pan is elongated and curved forwardly and downwardly to define in cross section an arcuate wall 47. The arcuate wall 47 forms one boundary of a throat 48 defined on its other boundary by an arcuately curved upper wall 49 which conveniently is the upward extension of a guide plate 51 detachably mounted on the back wall 22. The throat 48 has been found to work in an especially satisfactory manner when the cross sectional area of the throat 48 is substantially equal throughout its length except over the outlet portion 52 of the throat where the upper wall 49 is flared forwardly so as to enlarge the cross sectional area of the throat and in the fashion appearing most clearly in Figure 2.
The lower edge 53 of the pan rear wall 46 serves as the upper side of a channel 54 serving to vent the burner and griddle area and defined on its lower side by an arcuate inwardly and downwardly curved portion 56 of a front plate 57 conveniently supported on the stove top and held in vertical attitude by appropriate brackets 58 and 59 on the opposite end plates 16. The curved portion 56, or lower lip, of the channel 54 itself forms the upper and outer boundary of an oven vent passageway 61 whose other or inner margin is a vertical wall 62 forming with a forward horizontal projection 63 of the lower end of the guide plate 51 a trough 60, U-shaped in section. The trough 6th at the lower end of the guide plate 51 is conveniently supported by a reverse fold 64 in the back plate.
In the event it is desired to give additional support to the back plate 22 in addition to that furnished by the end plates 16, suitable brackets 65 projecting forwardly from the back plate may be supported on the upper side of the range. In some installations, it may even be desirable to extend the brackets 65 entirely across the upper rear edge of the stove from the one end plate to the other in order to prevent any grease from running down the back side of the stove and onto the floor. In such case, suitable apertures would be provided to permit the upward flow of cooling air from an air passageway 66 defined by the rear wall 67 of the stove and the lowermost portion 68, or skirt, of the back plate, the air flow being indicated by the arrows 70.
One of the unique and highly useful results effected by the ventilator of my invention is the venting of the oven spaces. Gases to be vented from the ovens include air heated to a temperature of approximately 500 to 550 F. in addition to steam, odors and grease in vapor form or in the shape of very small globules. These gases, collectively termed vent gases, pass upwardly through the vent pipe 12 and upwardly through a duct '71 defined by the back wall 22 and the front wall 57. Natural convection supplemented by the convection currents created by the fan 42 cause the vent gases to move upwardly in the duct 71 and to pass upwardly, rearwardly and downwardly through the arcuate passageway 61. The gases are deflected rearwardly by the curved portion 56 of the front plate and are caused to eddy within the L l-shaped trough defined by the upstanding plate 62, the bottom plate 63 and the rear portion of the guide plate 51. Concurrently, and under the same forces of 4 convection, cool air is drawn upwardly through the space or opening 66 defined by the rear wall 67 of the range and the skirt 68 of the back plate and, as indicated by the arrows 70 shown most clearly in Figure 2. As the cool air passes upwardly along with the vent gases, the various gaseous fluids are forced to merge as they progress upwardly through the passageway 61, and, as eddying takes place in the U'-shaped trough, the vent gases and the cool air, are even more thoroughly mixed or mingled so as to cool the vent gases to a considerably lower temperature than the 500 to 550 F. temperature possessed by the gases when they were within the oven. Particles of grease in the oven gas are also cooled to a considerably lower temperature and as the combined and cooled gaseous mixture continues to travel upwardly in the fashion shown most clearly in Figure 2 into the arcuate throat 48, the gases are caused to be reduced in temperature toan evengreater extent owing to the influx of air and other gases entering from the front side of the range and entering through the channel 54. The flow of gases is indicated clearly by several short arrows in Figures 1 and 2, the arrows indicating that in the area adjacent and above the hot burners 8 and griddle 9, the flow isrearwardly and upwardly toward the channel 54 under influence of the vacuum impressed upon the hood by the fan 42. The gases, such as hot air, steam, odors and vaporized grease are thereby swept rearwardly away from the oven and in a direction away from the cook, thereby rendering the range a much cooler and more comfortable place in whichto work, and, furthermore, being effective to remove these products from the surrounding kitchen area. Adjacent the front side of the facade plate 33 and around the bottom of the grease pan 37, substantially pure cool air is caused to flow, the vacuum existing at the channel 54 causing this movement of air. Thus, the continuous flow of cool air downwardly over the facade plate and along the underneath side of the pan bottom maintains the facade and the grease collecting pan at a considerably cooler temperature than would otherwise be the case. Owing to this continuous air flow the pan is held at a reduced temperature and thus is enabled to condense or congeal the vaporized grease and minute grease particles as they are swept through the curved throat 48 and are allowed to pass through the enlarged or expanded portion 52 of the throat and impinge against the cool bottom of the grease collecting pan 37. Thus, after the cooled oven or vent gases pass upwardly through the passageway 61 and through the trough they are co mingled with the reduced temperature gases flowing rearwardly through the channel 54, and, as both pass through the throat 48, an even greater cooling is effected as the combined gases pass through the enlarged portion 52 of the throat. The gases, upon entering the enlarged portion 52, are allowed to expand in a rapid fashion and thus lose a considerable fraction of their energy, with a consequent reduction in temperature. Furthermore, local eddies or whorls are effected which even further reduces the gas energy and lowers the temperature of the gases as well as the temperature of the grease entrapped within the gases. Thus, as the gases are blown against the relatively cool grease pan bottom, the vaporized grease and small grease particles are congealed or solidified and cling to the pan bottom. It has been found in practice that the large majority of the grease which is collected is located in the front portion of the grease pan and in the location and in the shape generally indicated by the dotted lines designated by the numeral 74. Not only does such a location and configuration of the grease permit of easy extraction of the grease for cleaning purposes but it also allows the pan bottom to continue with its condensing or congealing effect, since the cooler metal of the pan bottom is continually presented to the entering flow of gases.
While the ventilator of my invention works in a highly satisfactory fashion with the construction shown, ithas been found that in certain types of operation, for example, when cooking products having especially high grease content, that it is sometimes useful to employ a filter or baflie plate, generally designat:d 76, supported by suitable brackets 77 on each of the end plates.
Owing to the construction of the ventilator, the possibility of flash fires resulting from the combustion of grease vapors is largely, if not entirely, eliminated. Flash fires customarily arise from the overheating of vapors having a high content of grease, the grease being in vapor form. In the ventilator of my invention, however, the intermingling of the cooler air from the ducts between the end plates and range ends and between the back plate and range rear wall with the oven ven-t gases and the top of range gases reduces the temperature of the gases to such an extent that the probabilities of overheating of the grease are greatly reduced. Furthermore, the additional intermingling of the oven vent gases with the top of range gases flowing through the channel 54 along with the considerably cooler fresh air sweeping downwardly across the facade plate 33 and rearwardly across the bottom of the grease pan additionally cools the exhaust vapors and reduces the likelihood of fire. Thus, as the gases pass at a considerable velocity through the throat 48 and are suddenly allowed to expand into the enlarged portion 52 and thence against the relatively cold bottom surface of the pan, the grease particles previously cooled are suddenly chilled or congealed and collect in solid form in the pan. Grease which has congealed is unable to support a fire since, before combustion can be maintained, the grease must be changed into vapor form. It is therefore obvious that by chilling or congealing the grease as it passes through the various ducts and channels of the ventilator and particularly as it attains a solidified form Within the grease collecting pan the likelihood of a flash fires starting or of being ma ntained even if started is cut to a minimum.
It can therefore be seen that I have provided a ventilator capable not only of handling or venting oven gases and of gases arising from the top surface of a range, but I have also made provision for cooling these various gases and of congealing the greases within the gases so as to reduce the likelihood of flash fire; and have provided, furthermore, a ventilator which can be easily inspected to see when cleaning is necessary, and whose construction is such as to permit withdrawal of the various components of the ventilator to effect cleaning in a simple easy fashion.
What is claimed is:
A ventilator for use with a range comprising: a pair of end panels; a back panel extending between said end pan els; a hood mounted on said back panel and extending between said end panels, said hood including a substantially horizontal top plate extending between said end panels, a facade plate depending from the front edge of said top plate and extending between said end panels, a walled grease collecting pan including a bottom plate, said pan being detachably mounted on the lower edge of said facade plate in at least partially air-tight relation therewith, said pan extending laterally between said end panels and rearwardly toward said back panel, the back wall of said pan being spaced from said back panel to form a substantially vertical passageway therebetween, the upper portion of said back wall of said pan being recurved forwardly and downwardly toward said bottom plate; an exhaust fan mounted in an opening in said top plate of said hood and adapted to exhaust gases from the chamber within said hood defined by said back panel, said end panels, said top plate, said facade plate and said bottom plate of said pan; a deflector plate extending between said end panels and mounted on said back panel, said deflector plate projecting forwardly and downwardly and being in substantially uniform spaced relation with respect to said recurved back wall of said pan to form a throat adapted to conduct gases from said passageway into said pan; and a front panel vertically mounted on the range and spaced from said back panel, said front panel extending between said end panels to form with said back panel a vertical conduit adapted to conduct oven gases, said front panel terminating in a rearwardly projecting portion spaced from said bottom plate of said pan to define a channel therewith adapted to conduct gases rearwardly and to the entrance of said passageway.
References Cited in the file of this patent UNITED STATES PATENTS 2,392,038 Gaylord Jan. 1, 1946 2,393,957 Baumgartner Feb. 5, 1946 2,535,863 Pledger Dec, 26, 1950 2,748,688 Smith June 5, 1956