US3160737A

US3160737A - Switch mounting arrangement for a cooking top

Info

Publication number: US3160737A
Application number: US154209A
Authority: US
Inventors: George C Pearce
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1961-11-22
Filing date: 1961-11-22
Publication date: 1964-12-08
Anticipated expiration: 1981-12-08

Description

1964 e. c. PEARCE 3,160,737

SWITCH MOUNTING ARRANGEMENT FOR A COOKING TOP Filed Nov. 22, 1961 2 Sheets-Sheet l ZNVENTOR. 5a0rge (I. Pearce His A ffomey Dec. 8, 1964 G. c. PEARCE 3,160,737

SWITCH MOUNTING ARRANGEMENT FOR A COOKING TOP Filed Nov. 22, 1961 2 Sheets-Sheet 2 l g x l i l 50; i

l i i I I 4 l I I 1 l J I U "62 LWENTOR.

George C. Pearce His A for/lay United States Patent 3,160,737 SWITCH MOUNTING ARRANGEMENT FUR A COUKENG TOP George C. Peace, Dayton, @hio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Filed Nov. 22, 1%1, Eer. No. 154,2ii9 4 Claims. (El. 2ll9--4b"l) This invention relates to a domestic appliance and more particularly to an improved mounting arrangement for protecting electric range switches from condensate or spillover.

Protection of electric switches is one of the problems encountered in cooking ranges. These switches must be protected from condensate and spillovers which occur occasionally during the cooking process. For this reason, prior art devices have included resilient bushings or other sealing means in locations normally exposed to damaging moisture. Where an infinite heat switch is involved, the interposition of seals between the switch and its support creates another problema variable stress or pressure on the switch casing which adversely affects the switch calibration.

Accordingly, it is an object of this invention to provide a range top with a switch mounting arrangement to protect the switch from condensate.

It is also an object of this invention to effect a sealed electric range switch Without using resilient bushings.

A further object of this invention is the provision of a rigid mounting plate for an electric range switch which has a buffer dam for diverting condensate from the switch.

Still another object of this invention is the provision of means for diverting spillage from electric range switches rather than sealing the switches.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIGURE 1 is a fragmentary perspective view of a builtin cooking top provided with the switch mounting arrangement of this invention;

FIGURE 2 is a sectional view of the switch mounting arrangement taken along line 2-2 in FIGURE 1;

FIGURE 3 is a fragmentary top elevational view taken along line 33 in FIGURE 2 with the switch actuator knobs removed;

FIGURE 4 is a fragmentary sectional view taken along line i-4 in FIGURE 2; and

FEGURE 5 is a sectional view taken along line 5--5 in FIGURE 1.

In accordance with this invention and with reference to FIGURE 1, a built-in cooking top it) is illustrated. The cooking top includes a top panel 11 having a plurality of cooking unit openings 12 for receiving heating elements such as 14 therein. In one corner of the cooking top I is a switch assembly 16 which mounts the various switch means for controlling the heating elements 14 respectively. Beneath the top panel 11 and shown fragmentarily in FIGURE 2 is a cooking unit pan or subtop It on which the heating elements 14 are supported. Ad-

- ditional details of this arrangement for mounting the mounting bracket 22 and a switch operating shaft 26 extending upwardly through an opening 28 provided in the cooking top. It should be noted that four identical switches are shown in FIGURE 1 and in the following description similar components will have the same reference numerals.

Cooking procedures on the built-in cooking unit 10 frequently result in spillovers which, by way of gravity, flow through the openings in the cooking top 11 to the inner surfaces of the unit. For this reason, the prior art has provided drip bowls beneath the heating elements and bushings around the switch shafts to prevent damaging fluids from reaching the insides of the electric switches. This invention is directed to diverting these spillovers or condensates from the critical portions of the switch rather than sealing for protection. It has been found that prior art seals around the switch shaft 26 foster varying stresses on the switch casing when a seal is wedgedbetween the casing and its support.

The escutcheon 20 is best seen in FIGURE 3 and includes for each of the electric switches a recessed annular channel 32 which is formed with a bottom wall 34 and a radially inner upturned sidewall 36. The bottom of the channel is formed with six extruded downward ports or weep holes 38 for permitting drainage from the top of the escutcheon to the area beneath the cooking top. The sidewall 36 also serves to define a central opening 46 through which the switch shaft 26 may extend for engagement with the actuator knob 39. Thus the knob 39 of phenolic or other suitable material is formed with an indicia flange 44 overlying the channel 32 and a hub portion 46 which extends through the escutcheon opening ll for attachment with the switch shaft.

Turning now to FIGURE 4, the switch mounting backet 22 will now be more fully described. To provide rigidity, this mounting bracket is formed as a zinc base die casting. The bracket or casting 22 is formed integrally with four upstanding and tapped escutcheon mouthing bosses 50, a raised central collar 52 for receiving a pilot light (not shown) and four stepped switch mounting bosses 54. Each boss has a switch attachment platform or step 56 and a raised collar 58 for receiving the switch shaft 26 snugly but without engaging the shaft. On the top side of the casting 22 is an upper right angle rib 60 while on the underside of the moutning plate is a lower rib 62. Note that the upper rib 60 extends over that portion of the mounting bracket 22 that is not covered by the extended rib 62 therebelow. Notice also the turned-in rib portions as, 66 on the underside of the mounting bracket to prevent condensate from overflowing the edges of the bracket 22 and, by reverse flow, contacting the various switch casings. in other words, the upper and lower ribs 69, 62 shield the switches fromdamaging spillovers.

The switch mounting assembly 16 is assembled in the following manner. The switch casing 24 is positioned adjacent the underside of the plate 22 with its shaft 26 extending through the collar 58. Screws such as 70 are threadedly engaged with tapped holes in the switch casing through openings in the raised switch mounting boss potrion 56spacer washers 72 being provided between the screw head and the boss portion. Note that the switch casing 24 is fastened rigidly adjacent the underside of the mounting bracket 22. No bushing circumscribes and hugs the shaft 26 at the juncture of switch casing, shaft and mounting bracket. This effects an unyielding attachment between the switch casing and the mounting bracket so that no variable stresses are imparted to the top wall of the switch casing which could alter the calibration of the switch.

Next the mounting bracket 22 is fastened as by a screw 74 to the subtop or cooking unit pan 18 with the entire switch assembly positioned adjacent the opening 23 in the cooking top panel 11. The escutcheon 2a is then positioned over the opening 28 in the cooking top and fastened to the mounting plate 22 by means of screws 80 which engage the. mounting boses 50. Lastly, the. switch knobs 30- arefrictionally engaged with the switch shaftsl.26; andxa liquid or condensate-tight mounting, arrangement is completed.

In operation, let us assume that a spillover occurs during a cooking process on the unit 10. This spillage, if it falls on top of theescutcheon 20, will flow into the recessed channel 32. The weep holes or ports 38 will cause the condensate to drop to the mounting plate 22 therebelow. However, the raised collar 58 will prevent the condensate. or spillage from-touching the switch shaft 26-the oversizednature of the switch knob hub 46 acting as a cover for the open top of the collar 58. Once the spillage landson the top of the mounting bracket 22, the top rib 60 will divert it away from critical areas of the electrical circuitry lying adjacent the mounting bracket,.i.e., not only are the switches protected but the wiring as well. The underside or lower ribs 64 will prevent moisturefrom overflowing the edges of the condensate and coming in underneath the plate to damage the switches.

It should now be seen that an improved mounting arrangement has been provided-for an electric range switch which will protect against damage by spillageor condensate entering they switch assembly from the top of the cooking unit. Further, the calibration of the switch will remain more dependable, since the switch is mounted solidlyto its mounting bracket without the interposition of any resilient sealing means.

While the embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1.. lnlcombination, a cooking top having a heating element'openinganda switch opening, a cooking unit pan beneath said cooking top, a heating element in said heating element opening and" above said cooking unit pan, a. switch for saidheating element having a switch body below said cooking top and a switch shaft extending above said cooking top, a switch knob having a knob shankfor receiving said switch shaft, a switch mounting arrangement cooperating with said switch opening to support said switch in a manner to prevent spillage from reaching said switch shaft and to eliminate stresses on said switch body surrounding said switch shaft, said mounting arrangement including an escutcheon supported on said cooking top and having a recessed annular channel, said channel having a perforated bottom and a generally cylindrical sidewall concentric with said switch shaft, a die cast switch mounting bracket having a baffled imperforate plate portion larger than said switch body carried by said cooking unit pan and having a collar upstanding from said plate portion and smaller than the knob shank in a plane parallel to said plate portion, and means for fastening said switch body to said mounting bracket below said plate portion with the switch shaft freely extending upwardly through said collar into engagement with said knob shank, whereby spillage through the perforations of said channel bottom in said escutcheon is diverted away from said switch shaft and said switch body.

2. In combination, a cooking top having a heating element opening and a switch opening, a cooking unit pan beneath said cooking top, a heating element in said heating element opening and above said cooking unit pan, a switch-for said heating element having a switch body below said cooking top and a switch shaft extending above said cooking top, a switch knob having a knob shank for receiving said switch shaft, a switch mounting arrangement cooperating with said switch opening to support said switch in a manner to prevent spillage through said switch opening from reaching said switch shaft and to eliminate stresses on said switch body surrounding said switch shaft, said mounting arrangement including an escutcheon supported on said cooking top and having a recessed annular channel, said channel having a perforated bottom and a generally cylindrical sidewall concentric with said switch shaft, a die, cast switch mounting bracket having an imperforate plate portion larger than said switch body carried by said cooking unit pan and having a collar upstanding from said plate portion and smaller than the knob shank in a plane parallel to said plate portion, and means for fastening said switch body to said mounting bracket below said plate portion with the switch shaft extending upwardly through said collar into engagement with said knob shank, whereby spillage through the perforated channel bottom in said escutcheon is diverted away from said switch shaft and said switch body.

3. The combination of claim 2 wherein said plate portion includes abafiie for diverting spillage to a preselected part of said plate portion.

4. In a combination, a cooking top having a heating element opening and a switch. opening, a cooking unit pan beneath said cooking top, a heating element in said heating element opening and above said cooking unit pan, a switch for said heating element having a switch body below said cooldng top and a switch shaft extending above said cooking top, a switch knob having an indicia flange and a knob shank for receiving said switch shaft, a switch mounting arrangement cooperating with said switchv opening to support said switch in a manner to prevent spillage from reaching said switch shaft and to eliminate stresses on said, switch body surrounding, said switch. shaft, said mounting arrangement, including an escutcheon supported on said cooking top and having a recessed annular channel underlying said indicia flange, said channel having a perforated bottom and a generally cylindrical sidewall concentric with said switch shaft, a die cast switch. mounting bracket having an. imper-forate plate portion carried by said cooking unit pan, said plate portion having a baffie thereon for diverting spillage and a collar upstanding from plate portion and smaller than the knob shank in a plane parallel to said plate portion, and means. for fastening said switch body to said mounting bracket below said plate portion with the switch shaft extending freely upwardly through said collar into engagement with said knob shank, whereby spillage through the switch opening in the cooking top and the perforations of said channel bottom in said escutcheon is diverted away from said switch shaft and said switch body.

References Cited in the file of this patent UNITED STATES PATENTS 1,418,376. Jacobi June 6, 1922 2,551,759 Pence May 8, 1951 2,992,315 McDonald July 11, 1961 3,051,817 Pearce et al. Aug. 28, 1962 3,066,550 Sundberg Dec. 4, 1962

Claims

1. IN COMBINATION, A COOKING TOP HAVING A HEATING ELEMENT OPENING AND A SWITCH OPENING, A COOKING UNIT PAN BENEATH SAID COOKING TOP, A HEATING ELEMENT IN SAID HEATING ELEMENT OPENING AND ABOVE SAID COOKING UNIT PAN, A SWITCH FOR SAID HEATING ELEMENT HAVING A SWITCH BODY BELOW SAID COOKING TOP AND A SWITCH SHAFT EXTENDING ABOVE SAID COOKING TOP, A SWITCH KNOB HAVING A KNOB SHANK FOR RECEIVING SAID SWITCH SHAFT, A SWITCH MOUNTING ARRANGEMENT COOPERATING WITH SAID SWITCH OPENING TO SUPPORT SAID SWITCH IN A MANNER TO PREVENT SPILLAGE FROM REACHING SAID SWITCH SHAFT AND TO ELIMINATE STRESSES ON SAID SWITCH BODY SURROUNDING SAID SWITCH SHAFT, SAID MOUNTING ARRANGEMENT INCLUDING AN ESCUTCHEON SUPPORTED ON SAID COOKING TOP AND HAVING A RECESSED ANNULAR CHANNEL, SAID CHANNEL HAVING A PERFORATED BOTTOM AND A GENERALLY CYLINDRICAL SIDEWALL CONCENTRIC WITH SAID SWITCH SHAFT, A DIE CAST SWITCH MOUNTING BRACKET HAVING A BAFFLED IMPERFORATE PLATE PORTION LARGER THAN SAID SWITCH BODY CARRIED BY SAID COOKING UNIT PAN AND HAVING A COLLAR UPSTANDING FROM SAID PLATE PORTION AND SMALLER THAN THE KNOB SHANK IN A PLANE PARALLEL TO SAID PLATE PORTION, AND MEANS FOR FASTENING SAID SWITCH BODY TO SAID MOUNTING BRACKET BELOW SAID PLATE PORTION WITH THE SWITCH SHAFT FREELY EXTENDING UPWARDLY THROUGH SAID COLLAR INTO ENGAGEMENT WITH SAID KNOB SHANK, WHEREBY SPILLAGE THROUGH THE PERFORATIONS OF SAID CHANNEL BOTTOM IN SAID ESCUTCHEON IS DIVERTED AWAY FROM SAID SWITCH SHAFT AND SAID SWITCH BODY.