US1836606A - Edward lapp - Google Patents

Description

Patented Dec. 15, 1931 UNITED Vs'r-ivras MPP, EDWARD A. mE, AND ALBERT WOLPERT, 0l' PITTSBURGH, PENN- snvnrn, Aiselieifona To rrr'rsntmeii warm. marmi. confirm, 'or

Birnen, rvnna, roonronarioit or imw .mnsmr ens man mm Appunti nien man sa, 1mi?. semi no. 117,240.

This invention relates to s fired heaters, and more -particularly to pi ot' valve devices apglicablejwsuch heaters.

e (Ali-:fthe primary objects of our invention is to the certainty and safety of l operationiii as fired heaters.

' tain the Afggnfegoin plates the rovision of means'under the insaid thermosta Anotherobpct of the invention is'to atby simple vand direct-acting meansfwith t e least possible -complica-l tion of apparatus. 4

More "specifically, 'our invention conteinfluence of t e pilot li ht of/a gasheater to control the admission o s to the main burner, and we have embodie the invention in pre- Aferred form, in a safety pilot valve, operating,`when the pilotis burning, to provide an open connection'fromthe usual thermstati``- call -controlled valve in the gas supply line to t e main burner, and when the pilot is not burning or has one out from any cause'what-I ever,` to shut o such connection so that no gas will be delivered` to the main burner,even if the thermostit becomes cold and opens the ically-controlled valve.

The nature objects and advantages of the invention will from the following description, reference being had to the accompanying` drawings, wherein c f Fig. 1 is anelevational view of a gas waterheating apparatus embod ing our invention, a certain portion of the" gure being in section; and 1 v Fig.,2 is an enlarged vertical longitudinal sectional view` of the safety pilot valve einplryed. in carrying lout the invention.

eferring now to Fig. 1, it willbe seen that we have therein illustrated a water heater 2, having a shell 3, a water heating'coil 4, and a main burner 5,-syupplied with gasfromthe pipe or main 6 through the intermediation of certain valves, to b e hereinafter described.

A pilot 7, so mounted as to .extendinto the heater tthrough the shell. 3, is supplied gas, as from` the-hinein 6, through a however, appear more clearly 4and clampin the diap controlled by avalve 9, and is provide with one or more orices 10 (see Fig. 2) adapted to project a constant flamel in :proximity to the i main burner 5.

. l The gas supply to the m'ain'burner from the .A gas l 1 ipe 6 is by way of a hand-o rated valvev normall open) a control 'ng valve 12 'of any suita le ty for example'v athermostatically-'operate valve, (such valves, oper`A able upon a drop or rise in the temperature of Water in the storage tank 13 belowor above a certain predetermined point, respectively,

being well knownl in the art); and\ from thence throughfalpipe 14 in which is placed the safety lp1 ot .valye device 15 'of the present invention [(i'iormally held in open position under the" infiuence of the heat rom the pilot2 by means now to be described).

The pilot valve device 15, which may be mounted on the heater shell 3, by bolts 18, has avalve chamber 16, communicatin at top and bottom with thegas line 14o the.`

burner, and enclosing the valve partsproper, -1 v and a second chamber or cavity 17 surrounding the outer portion of the pilot and containing valve-controlling means adapted to be heated thereby. The cavity 17 (asshown in Fig. 2) may be open at'the bottom, and f communicates vnear the top through aport 19 into the heater casing to provide a flue above the pilot, which latter is provided with a jet openin 10a outside the heater casing 3. Po. sitione near the flame from jet 10a is` a curved, expansible andcontractible, or ther- 'i ymostatic element20, one end of which is fixed at 21 .and the other end of which 'is attached to or en ages the end 2,2 of a lever 23 pivoted at 24. pin 4or stem25 as by means of lock nuts 2 6, said vstem being in two arts, screwed together ragin 27 between them as shown-in ig. 2.

The lmechanism in valve, chamber k16 is e operated by4 means of the .stein 25 which is he other end of lever-23 engages apositioned by the diaphra 27 pinched between the casing of cham er 16 and a cap 28. This construction permits of lo-n itudinal motion of the stem by flexure ot the diaphragm, b-ut prevents gas from escaping around the stem. The upper end of stem 25 engages a lever 29,as by means of lock nuts 30, said lever being fulcrumed at one end at 31, and at the other end engaging the a'ction spool 32 of the valve 33, which latter is adapted to seat at 33a. The spool 32, slidable on valve stem 34, bears upon the valve through the intermediation of a positioning spring 35. The stem 34 is positioned by a sleeve-like guide nut 36, having longitudinal openings or grooves 36a providing passage for the gas, and a lock screw 37 in its upper end for adjust-ment of the nut longitudinally of the valve stem. The valve is of the'snap action type, such action being obtained by meansot the lixed spring or springs 38 whic engage a beveled annular rib 39 on s ool 32. The snap action may be accentuated y constructing the lever 29 of av relatively thin strip of spring steel or other suitable resilient material.

It will be obvious that the cap into which the gas inlet pipe 14 is screwed serves to secure the parts inside 'the casing as well as to 'give access thereto for inspection, removal or repair.

From the foregoing description it will be clear that in operation the device provides an open connection for the gas to the main burner as long as the pilot remains lit, the heat from the pilot jet 10a maintaining the curved thermostatic element 2O in expansion. thus holding the valve 33 open (as shown in Fig'. 2) by means of level` 23, stem 25, lever 29, spool 32 bearing upwards against guide nut 36, and valve stem 34 iixed in said nut. 1Vith thesafety pilot valve so held open (which is its normal position) gas will low therethrough from 'pipe 14 to the main burner 5, whenever thermostat valve 12 is opened by a drop in the temperature of the water in the storage tank 13 below a predetermined point. if, however, the pilot light at any time should go out, expansion element 20, deprived of the heat or jet 10a, will exert a force by contraction which pulls down on stem 25 and thence on lever 29 and spool 32,- the rib 39 thereof snapping below the ends of springs 3S, and the valve 33 closing under the pressure then put upon spring 35. The length and tension of this spring, with relation to the position of the spool when the rib 39 is below the ixed springs 33, is such that valve 33 is maintained iirmly seated at 33a. Relighting of the pilot will, of course, cause a reversal ofthe foregoing valve action.

It will be seen that by our safety pilot valve device we have provided a positive and direct-acting means lunder the influence of the heat of the pilot' to shut oi, by snap action, the main gas supply to the burner in case such pilot light fails, that the device is compact, rugged and easily adjusted or repaired, and that new pilot tips or expansion elements may be inserted without any necessity of opening the gas chamber of the valve.

What we claim is 1. A pilot controlled valve device comprising a thermostatic element positioned within the influence of the ilot light, a gas supply line, a valve in sai line, and operating connections between said valve and said element, including an faction member .resiliently associated with the valve, resilient mea-ns for holding said member in either of two positions, and lever means operatively connected between said member and said elelment to move the member from one position to another upon expansion or contraction of said element.

2. A pilot controlled valve device compris ing a thermostatic element positioned within the influence of the pilot light, a gas supply line, a valve in said line, and operating connections between said valve and said element, including an action member associated with the valve, resilient means for holding said member in either of two positions, a pivoted lever engaging said element, a resilient lever engaginff said member, and an operating connection between the levers.

3. In a pilot controlled valvedevice ofthe character described, a valve havinga stem, a sleeve threaded on the stem for adjustment, a spool slidable on the stem between the sleeve and valve, a pilot, actuating means for sliding the spool, said means being operable by the heat of the pilot, and resilient means engaging the spool yieldingly resisting initial sliding movement thereof.

4. 1n a pilot controlled valve device of the character described, a valve having a stem, a sleevethreaded on the stem for ad] ustment, a spool slidable on the stembetween the sleeve and valve, a pilot, actuating means for slid ing the spool, said means being operable by the heat of the pilot, and resilient means en-l gaging the spool yieldingly resisting initial sliding movement thereof, together with a spring interposed between the spool and the valve.

5. In a pilot controlled valve device of the character described, valve having a stem, a sleeve threaded on the stem for adjustment,

a spool slidable on the stem between the a sleeve threaded on the stem for ad]ustment,

a spool slidable on the ystem between the v sleeve and valve a pilot, actuating means for sliding the spool, said means being operable bythe heat of the pilot, and resihent means 5 en aging the spool yieldin lyresisting initial sli ing movement thereofut finally accelerating the movement.

In testimony whereof we have hereunto signed our names. A lo EDWARD LAPP.

EDWARD A. KRAH, JR. ALBERT WOLPERT.

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