US3041629A

US3041629A - Flushing apparatus

Info

Publication number: US3041629A
Application number: US790522A
Authority: US
Inventors: Verneur E Pratt
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-02-02
Filing date: 1959-02-02
Publication date: 1962-07-03
Anticipated expiration: 1979-07-03

Description

July 3, 1962 v. E. PRATT FLUSHING APPARATUS Filed Feb. 2, 1959 6 2 M ,7p 6 M 7 .M ,lum man J, hm

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Unit tages The .present invention relates to flushing apparatus and more particularly to an apparatus yfor flushing toilet bowls and the like.

The conventional -toilet flushing apparatus employs a vitreous tank adapted to impound or hold a certain quantity of water, for example four or tive gallons at a ten or eleven inch hydrostatic head, having an inlet adapted to be connected to a source of water under pressure and an outlet connected to a toilet bowl. The conventional Iushing apparatus further includes a ball-cock mechanism, eg., a ioating hollow ball coupled to a valve in the inlet by means of a suitable leverage mechanism to close the inlet to the tank when the liquid therein reaches a predetermined level. The outlet of the tank is normally closed by a suspended ball that drops, or at least is designed to drop, over a seat which surrounds the outlet in the base of the tank.

This conventional toilet ushing mechanism is complicated, expensive and requires many parts which are constantly exposed to the water within the tank. To prevent excessive corrosion of the parts they are generally made of brass which adds to the manufacturing cost of the conventional liushing apparatus. However, in many areas the water is very corrosive even to brass parts and in such areas conventional ball-cock mechanisms are continually being replaced. Even in other areas Where the water is not so corrosive to brass parts such apparatus requires constant attention to maintain it in an operative condition. Furthermore, the conventional toilet flushing apparatus is noisy and unreliable. For example, the water inlet to the tanks of the conventional ushing apparatus is generally located above the maximum Water level Within the tank so thatr during the entire refilling operation of the tank a loud and undesirable noise is created by the water gushing vfrom the inlet and striking the surface of the water within the tank. A disturbing whistling noise is also created by the gradually decreasing Water iiow through the inlet due to the restricting action of the inlet valve as the oat is raised by the water level during the -relilling operation. These noise signals are rendered more disturbing by the amplifying action of many conventional vitreous tanks which are resonant at the frequencies of the noise signals. Also the floating ball valve frequently fails-to close the outlet of the tank after the flushing operation is completed,

permitting water to continually dribble into the toiletA bowl until the operating handle that is coupled to the ball is jiggled or some more drastic measure is taken to drop the ball to its seat.

The space required by the conventional vitreous china tank is also undesirable, especially in modern homes- Where lthe bathrooms are small. To overcome this disadvantage the tanks for storing the flushing water have been placed in the wall between the studs. However, the tanks that have been lplaced in the wall are merely the standard rectangular vitreous tanks with the same ball-cook mechanisms. While these tanks are out of the Way, they still require constant servicing, a large panel in the Wall to provide access to the tank, and hold four to ve gallons of water with'the conventional ten to eleven inch hydrostatic head. i

It has been discovered that a more adequate flush of a toilet bowl is obtained by delivering two or three gallons of Water to the ybowl from a long vertical tank to provide a four or tive foot hydrostatic head than by ilushing the bowl with twice the amount of water under only Y a ten or eleven inch head.

Other types of less conventional iiushing apparatus have heretofore been proposed in an attempt to eliminate the ball-cock mechanism and its inherent shortcomings, but these types of apparatus have not been used to any great extent for various reasons. See, for example, U.S. Patents No. 1,383,273 issued to A. H. Klahn; No. 1,995,358 issued to C. E. Mace, and No. 2,055,271 issued to P. E. Vuagnat.

These proposed flushing devices include a tank having an unrestricted inlet and an outlet and one or more valve members such as a ball or a plurality of valving discs disposed Within the tank and arranged tobe normally pressed against one or more seats surrounding the outlet by the water pressure within the tank. A lever mechanism including a handle is provided for lifting the valve member or members from their seats to initiate the flushing operation. While these proposed ydevices eliminate the necessity for the conventional ball-cock mechanism and its associated problems Vthey encounter another problem as a result thereof. By providing an unrestricted inlet so that the water pressure Within the tank controls the ow of water through the inlet the" valve member or members for closing the Voutlet must be 'lifted against the full pressure of the source that is connected to the inlet. Where the inlet of the tank is connected to a city water main the pressure at the inlet when the outlet is closed may be of the order of 40 to 50 p.s.i. To move even a small valve member against such a high pressure would be a monumental task for the average user of a toilet unless an expensive leverage mechanism were employed with its inherently long operating stroke `or some additional source of power were used to open the outlet.

In summary, the previous attempts to produce a `better iiushing apparatus were too complex, impractical or expensive to manufacture and, therefore, could not meet the economical test that competition in this iield dictates.

The above disadvantages have been overcome by the flushing apparatus of the present invention which Vis reliable, inexpensive to manufacture, simple in structure, quiet and eicient in operation. The apparatus of the present invention also requires little maintenance and may provide a hydrostatic head of several feet by impounding the flushing water Within a vertical tank which may conveniently be housed between the studs in the wall of a bathroom so thatthetank is completely out of the way.

In accordance with the present invention there is provided a liushing apparatus which includes a tank having an inlet adapted to be connected to a source of liquid, such as water under pressure, and an outlet. Valve means are coupled to the outlet for controlling the flow of vwater therethrough with the valve means beingV arranged to close the outlet normally. v For example, such valve means may includean impermeable sphere such as a plastic ball disposed `within the tank and adapted to cooperate with an annular seat surrounding the outlet so that the sphere or ball is normally forced against the annular seat by the pressure of the water Within the tank. the tank is connected 'directly Yto a source of water under pressure the pressure within the tank when the outlet is closed becomes equal to the pressure of the source which may be ofthe order of 40 or 50 p.s.i.- This high pressure insures a good seal between the ball and the annular seat, thereby preventing any water from dribbling into the toilet bowl between flushing operations. The flushing apparatus also includes means for operating the valve meansV to open the outlet and means to reduce the pressure within the tank prior to operating the valve means. Where the valve'meansA includes a ball and cooperating annular seat Patented July 3, 1S62 Since the inlet to surroundingthe ontlet, the Imeans for operatingnth'e valve I Vmeans may include a cam, disposed below the ball, for

lifting the ball from the seat when the cam is turned and the means for reducing the pressure within the tank may w include a conduitin Yiluid communication with the tank and a plug valve coupled tothe conduit for draining'water from the tank just before the cam engagesfthe Yball to reduce the pressure within the tankl andthereby reduce the force required to lift the ball toopen the outlet.

The invention is described in more detail in connection with the accompanying drawing in which: Y Y

FIG. l is an Yelevation illustrating the .apparatus of -the Vena-1,629 j t c secured at its lower end to a drain pipe 68 which is in turn present invention connected toa toilet bowl with the water y tank disposed within a wall; Y v

FIG. 2 is a sectional VVview taken along the lines 2 2 of FIG. 1, partly broken away; 1 y Y FIG. 3 is a sectional view taken along line 3-3 of FIG.` 2; Y Y

FIG. 4 is an elevational View of a pressure regulator that may be employed with ythe apparatus of FIGS. 2 and'3.'Y Y Referring now to the drawing and more particularly to FIG. 1; a conventional rear Vspudded washed-downtype of toilet bowl is indicated generally at 10. The toilet bowl 10 is supported by a lloor 171. A vertically extend;`

Ving tank, indicated generally at '12, is secured to the .rear `of the bowl 10 by means of an velbow 14 and a bracket 16.

The tank 12 is disposed between the usual 6-inch studding within a wall having front and'rrear surfacesVV y18 and 20 connected at its lower end to the bracket 16, as showmto drain Vany w'ate'r that ymay flow lthroughthe opening 60 andthereturn pipe 64 intthe dischargechamber 17 and the toilet bowl connectedthereto.y

To lift the ball 50 frorn'its seat 35 and thus open the outlet, a cam 'l0-having a cam4 surface 72 onthe toppertion thereof and a segmentalpinion gear on the bottom portion is secured to an operating shaft7 8l which journaled in threaded bushingsV 80 that are threadedly engaged in hollow bosses 81 of the bracket 16. The shaftV bosses S1 and the hexagonal heads of the hushings.` An operating handle 92 is suitably secured to one end Referring now/to FIG. 2, the tank 12 includes'an inlet 22 which is connected to a suitable source of liquid or water under pressure -by means of an inlet pipe 24 which Vmay, for example, -be the standard 3/g'rinsiderdianreter service pipe which is inserted into a tting 26 and-secured` thereto in a water tight Vrelationship by means o f a hexaof the shaft 78 to actuate the cam l7|).V l Y To reduce the pressure within: the tank 12 priorv to lifting the ball 50 from its seat 34 the cam 704is arranged to control a pressure released plug valve indicated generally at 92p. SeeY FIG. 3. The plug valve 92 is clis-AV gonal cap 28 and a rubber sealing ring 30. The Vtank 12 in# cludes an outlet 32 through which Waterimpounded within the tank 12 may ow into the toilet bowl'10,as willrbe more fully described. yAn annular gasket 34; which may be for-med of molded `butyl rubber or neoprene is secured between an annular ofrrbracket 36 which forms the bottom of the tank 12 and an upper llange 39 ofthe bracket16.

y The gasket 34 includes an annular seat 35 which surrounds the outlet 32. The bracket 16 includes a centrally disposed discharge opening or chamber 17 through which the waterV impounded in the tank 12 ows to ush the toilet bowl. The. bracket v36 includes a vertically extending flange 37 which is suitably secured in a water tight vmanner to theV bottom of a stand pipeY 40 which forms the central Yportion ofthe tank 12. The bracket 16 includes a nipple 38 at the lower end thereof which threadedly engages the elbow 14 and the ange 39 at the upper end which is securedto the Vbracket 36 lby means; of bolts 42. An O-` ring Y44 is disposed between cooperating annular grooves 46 formed in the bracket 36 and the Vflange 39 of the' bracket 16, as shown, to make the tank 12 water tight.

A valve member such as a plastic ball 50 is disposed n within the tank 12 and Vadapted to cooperate with the annular seat Vformed bythe gasket 34 to provide a water discharge vcheck valve which normally `closesY the outlet 'ofthe tank and prevents water how therethrough. Another ball 52 which is arranged to tloat isV disposed within the tank 12Y and adapted to cooperate with anananular seat 54 formed by a gasket 56 to provide' an airVA release check valve, as will be more fully described. The gasket S6 is suitably secured to a top bracket member YSS that forms the top of the tank 12'. The bracket58 has a` centrally located holeV 60 therein which may be formedA by a plurality of coaxial annular grooves 61, as shown, to

cause the ball 52 to seat against the gasket 56 and close theopening 60 wherttheA water withinthe tankreaches a predetermined leveL- The opening -60 in the bracket 58 isin uid communication with a chamber 62 formed withf posed outsideV of the tank 12 and is coupled to a conduit indicated generally at 93 whichgis in fluid corn-p munication with the tank 12 and permits water to drain from the tank when the valve 82 is open. The valve 92` includesV arplunger 94 'which is slidably disposed within a bore 96 in a cylindrical member or tube97 that Yerr-Q tends across the'central portion of'the'bracket 16 and may be formedintegrally therewith. The plunger 94 includes a gear rack 9S on the top portion thereof adapt-j ed to mesh with the pinion gear` 74 so thatl the plunger; 94 is moved in the direction of the arrow in FIG. 3' as the cam'memb'er 70 is rotated in a clockwise'direc-' tion as viewed in FIGfB. A cylindrical gasket 98 isc carried by one end of the' plunger and is adapted to cooperate with an annular valve Vseat 100 formed on Vther end otra threaded insert 102 having a cylindrical bore 103 therein. The insert V102 forms apart of the 'conduit 93 Vand includes an opening 104 in the top portion thereof which is connected to the tank 12 by means of a' pipe 106. The insert 102 threadedly engages one end of the tube 97 and is sealed thereto. by means of sealing" rings 1 -08 vto prevent water within the `tank`12 frontV escaping into the discharge chamber 17 in the bracket 16 when the valve 92 is closed or when the plunger 94 is pressed against the seat 100. Thev tube 97 includes slots 110 therein to `perlnit Water to tiow from the conduit V93 through the tube 97, into the discharge member 17 and thence into the toilet'bowl when the valve 92 is open.

To hold the pressure release valveV 92 closed between flushing operations, a springl 112 is coupled at one end' of the shaft 78`by means of ancarm 114 and at the other end toa spool 116 which is secured to the'bracket y16 by meansof a bar 118, as may'best be seen in FIG. 2.

The spring 112must urge the shaft 78, as seen in'FIG. 3,' in a counterclockwise direction with suticient forceY to insure that the pressure Within 4thetank 12 and theY conduit 99Y will notopen the valve 92.' Y

V'111e `operation of the apparatus described above is as, follows: Assume that the tank 12 isffull of water and that the balls 50 and52 are pressed against their respec-V tive seats 35 and 54, as shown in FIG. 2 bythe pressure of the water in the tank which is equal to the pressure of the incoming water in pipe 24. To flush the toilet bowl theY handle 92 is depressed, which turns the shaft 78 and the cam 7u in a clockwise direction, as viewed in FIG. 3. The pinion gear 74 on the cam 70 engages the gear rack 95 on the plunger 94 and retracts the sliding plunger 94 away from the valve seat 100, thereby permitting water to surge from the tank 12 through the conduit 93, through the slots 110 in the tube 97, through the discharge chamber 17, and into the toilet bowl. In turning the cam 70 through a small arc, for example 5 to 7, enough Water has surged through the conduit 93 to lower the water level in the stand pipe 40 and drop the upper ball 52 from its seat 54 so that the water pressure on the top surface of the water within the tank 12 is equal to the atmospheric pressure in spite of the incoming water from the service pipe 24. The cam continues to turn as the handle is further depressed and the cam surface 72 of the cam 70 now engages the ball 50 and rocks the ball 50 to lift it from its seat S1. This opens the outlet 32 and permits the Water within the tank 12 to llush the toilet bowl 10.

Since only the weight of the water within the tank 12 is applying pressure on the ball Sil at the time the cam 70 engages the ball, 4little force is required to lift the ball from; its seat. The cam surface 72 further reduces the force that must be exerted on the handle 92 to lift the ball from its seat 51 by rocking the bal-l 50 instead of lifting it straight up. The water within the tank 12 is quickly delivered to the toilet bowl 10 because, as they water level within the tank drops, air rushes into the tank through the collar 66, the conduit 64, the chamber 62, and through the hole 6@ in the top bracket 5S. The ball 52 falls to the bottom of the tank 12 as` the irnpounded water therein is drained through the outlet 32 and assumes the position indicated by the dotted 'lines in FIG. 2 when the tank is almost empty.

To delay the return of the handle 92 and the cam 70 during the flushing operation, a conventional mechanic-al timer 120 is secured to the bracket 16 by means of a bar 121 and is suitably coupled to the shaft 78. The timer 120 may consist of a simple gear train with or without a nal windwheel or an air or oil dashpot. The timer 120 should be arranged to provide little or no resistance to the movement of the shaft 78 in a direction to open the outlet of the tank. Where the tank 12 is arranged to hold only two or three gallons of water and the plumbing code in a particular area requires that four gallons of ilushing water be delivered to a toilet bowl,

the timer 12@ may be arranged to delay the return of the handle 92 for a suicient length of time to permit the incoming water through the service pipe 24 to deliver the required additional amount of Water to the toilet bowl. The timer 120 may be omitted where the ball 50 is also arranged to float in the liquid that is impounded Within the tank 12 and where the tank 12 is designed to hold the required amount of water for ilushing a toilet bowl or the like.

After the toilet bowl 10 has been flushed the handle 92 and the shaft 78 are returnedto their original positions by the spring 112. This operation closes the valve 92 and permits the ball 50 to engage its seat 35. The incoming water through the service' pipe 24 now begins to fill the tank 12, causing the ball 52 to rise with the water level. When the tank is full the ball 50 engages its seat 54, thereby sealing the tank 12 to atmosphere and permitting the pressure within the tank to assume the pressure of the incoming water.

The stand pipe 40, the

brackets

16, 36 and 58, and the balls 50 and 52 may be made of a polyvinyl chloride plastic which is now extensively used and will withstand pressures of the order of 170 p.s.i. at 74 F. The use of a plastic material for the tank 12 provides a water tank which is nonresonant at the frequencies of the noise 5 signals generated by the owing water'within the tank, thus reducing the noise level during a flushing operation.

By employing spheres for valve-members which are free to land on their seats at a different peripheral circle each-time, the wear on the valve members is reduced appreciably. v

The apparatus of this invention also removes the necessity of having any metallic parts disposed within the tank 12 and thus constantly exposed to the impounded water, as Iis true in the conventional ushing apparatus. The only parts of the apparatus of this invention which may need to be formed of metal, i.e., the cam 70 and the plunger 94, are exposed to water only during the ushing operation, thus permitting such parts to dry when the toilet is not in use. The apparatus of this invention also provides an effective method of preventing material from depositing or collecting on the valve members or balls Sil and S2 in that these balls are flushed by the incoming water through the service pipe 24 at each flushing operation. Also the tank 12 ofthis apparatus is filled through an inlet that is disposed near the bottom of the tank which permits most of the tank to be lled by Water that is drawn into the tank under the water level therein which appreciably reduces the noise created during the refilling operation.

In regard to the requirements in most plumbing codes that the flushing apparatus acts as a vacuum breaker and an anti-Siphon device to prevent contaminated water from the toilet bowl from flowing back into the service pipe 24 in the event of a failure in the city water system, the apparatus of this invention permits only the uncontaminated Water within the tank 12 to be drawn into the service pipe 24. When the water level within the tank reaches the level of the service pipe 24 only air can be drawn into the service pipe. i It will be noted that, in installing the apparatus of this invention and preparing for possible future repairs or replacements, a large, unattractive access panel such as is used with in-the-Wall conventional rectangular tanks, is not required, nor is a full length access panel on the rear opening into `a closet or hall required. Because all of the working mechanism is low, the panel 21 may be small and still provide access to all workingparts for adjustment, repair or replacement. This panel may be even smaller than the front of the customary vitreous china tank. y

In those lcases where the toilet bowl itself must lbe uuseated because some'foreign object is lodged in it, or it must be replaced due to cracking or breakage, then the tank 12 can be raised-suciently to permit the plumber to unseat thebowl from its putty and the horn,v the horn being usually no longer than one and one-half inches. Dimensions for storing the tank 12 are essentially standard and thus determine the maximum length. For example, toiletbowls are seldom higher than 16 inches from the oor and seldom lower than l5 inches, While the oeiling height within the studs is customarily no more than 96 inches. Accordingly, as an article of manufacture, the tank 12 may be of maximum length of 72 inches, considering that the bracket 16 must occupy a minimum of eight inches, and that some space must be provided between the top of the tank 12 and the ceiling to permit the tank 12 to be raised in order to unseat the bowl.

When codes or convenience in manufacture, installation or shipping so dictate, then standpipe *40* may be in two parts with suitable connecting iianges.

From the foregoing description throughout it will be evident that the present invent-ion, when properly made and assembled, provides a new and unique answer to the problem of water-ilushing a standard toilet bowl. From the foregoing description it will be observed that, with very little pressure, the lower lball 50 may be raised for Y apri-,629

herhaal. tobeV raised against citywater pressure. `From the' foregoing description it will also vbeapparentfto. 'those skilled; thevartthat, barringraccident, this device should Y laspa; lifetime, due to the( fact that, wi'thin the water, ahamberhlere arena-metalrarfr, and the furtherrfaft that the valve member Aor balls 50 and 52 are continu- .cpsly washed bywater under pressure. Y *A Y I f desired, aconventional pressure regulator 130 may be provided at the inlet tothe tank 12;V or in series with the service pipe Z4, as shown in FIG. 4, to reduce the maxmumwater pressure within the tank 12. Forexample, the regulator 130 maybe arranged to Yprovide a pressure of 1 ps i. inthe tank 12. Experi- `in eiits:have proven that this low pressurev is suiicient iliir Seats Y.

What is @aimed iS= to provide Yagnod seal between the balls- 50 and 52 and @als llagga Ynt Opening in. the top Portion 'theraof, anoutlet in the bottom portion thereof and aninlet `adaptedrto be vconnected to a source of water under pres- Y sure, a-iirstimpermeablelbuoyant ball disposed within Ythe tank, for closing the airvent opening whenthe water within the tank reachesa predetermined level, arsecornd impermeable ball disposed within the tank for closing for ventging Ythe air vent opening to atmosphere and for draining offany' water that liovvs through the air vent openingfinto the discharge opening within the bracket, a @naait @needed between the rank and the bracket for draining water from the tank into the discharge opening, a plug valve coupled to the conduit andV including a v alve seat on one endofthe conduit and a plunger slid,- ably disposed within the bracket for selectively engaging the valve seat to closel the conduit, the plunger inabiding a, searrask, 'a Cam member rotatably mounted withinthe bracket and having asegmental pinion gear on one portionvthereof and aV cam surface on another portion thereof,jthe pinion gear meshing with the gear rack o n the plnnger to slide the plunger away'from the valve Seeland 'open the carrdut'when the Gammember, isl for tatedV in one direction and'to slide the plunger Vtoward the valve seat tovclovse theconduit when the cam member is rotated in the other direction, the cam surface being posi-I tionedtoengage and lift the second ball from the outlet whenp the cam member is rotated in said one direction l after the conduit isY opened, means vfor biasing the plunger tpward valve seatwand means for rotating Athe cam aimberirr ratione 1iirr=tii rrv v 12. apparatus for flushing toilet bowlscornprising a {tank}including a vertically disppsedrstand pipe, agnfirst breek?? haringen Outlet Perrine therein connected to the bottpmvvofthe stand pipe and*` a; second 4bracket having Brieven? Oprring'therein ccrrilectri` to the top of 'the fanti `Pipe 'the tank furfherirrhrdirrg arr inlet Opening in the wall of the Istand pipe adjacent the lower end thereofpmeans for connectingY the inlet to a source of water underpressure, means defining first and second annular valve seatsI disposedwithin the outlet and air vent openf 's ings in the Yfirst and'second brackets respectively2 first and second impermeable balls disposed within the stand pipe for cooperating' with the first ,and `secon'd'valve sea-tn respectively, `the second ball being buoyant and arranged t-o float inl the water Within the stand pipe for engaging the second valve seat when the water within Ithe stand pipe reaches a predetermined level, a third bracket'h-av-ing a centrally disposedv `discharge opening therein connected to the first `bracket land extending downwardly therefrom for connection to thev toilet bowl, the second bracket having a chamber connectedwith the air vent openinga first return pipe connected Ywith they chamber in the sec ond bracket and extending downwardly therefrom, 'a second return pipe connected to the discharge' opening in the third bracket at one end and extending generally upwardly therefrom with the upper end of Vthe second ren l, In an apparatus for flushing/toilet bowls thecombi Vnation which comprises a vertically'wdisposed cylindrical turn pipe being disposed a predetermined distance'below the lower end of the first return pipe, a collar of larger diameter than the first return pipe connected to lthetop end of the second return pipe and extending upwardly around the lower end of the rst return pipe to provide a space between the upper end of the collar and the rst return pipe to vent the chamber in the second bracket to atmosphere, `a conduit connected. between the discharge opening in the third bracket Iand the interior of the tank, a tubular member having slats therein connected to one end of the conduit and extending across the third bracket, means.Y forming a third annnl-ar valve seat onkthe end of the conduit connected to the discharge opening in the third bracket, a plunger slidably disposed withinthe tubular member -aud having a gear .rack on r one portion thereof, a shaft journaledVV on oppositefs'ides lifting the first bail from the first valveseat after the plunger has been removed from thelrird valve seat in response to` rotation of the cam member Vin said one direction, a handle connectedto the end of the vshaftth-at extends outside of the third bracket for turning the shaft in said one direction, spring means` coupledto `thefshaft for biasing the shaft in the other direction anda timer coupled tothe shaft for delaying the return of the handle and the shaft in saidV other threction.V

Y References Cited in the file of rthis patent UNITED STATES PATENTS" Y 679,687 simpson v r r July so, 1901 1,141,354 Mauer -7.....- June 1', 1915 1,305,145 Meyer` v. j May 27, 1919 1,639,288 Giardino et al Aug. 16, 1927 `FOREIGN PATENTS 'Y 14,121 Great Britain Ju1y'1'7, 1899 331,915 Italy Nov. 19, 1935 France ...Q -...1., A Nov. 24, 1954 UNITED STATESV PATENT OFFICE CERTIFICATE OF CGRRECTION Pai-,ent vo. 3,041,629 July 3, 1962 Verneur E. Pratt It is hereby certified that error appears i'n the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 43, `strke out "of"; column 4, line 26q for "7" read 78 line 38, for "82" read 92 SignedV and sealed this 30th day of October 1962.

(SEAL) Attest:

DAVID L. LADD VERNEST W. SWIDER 'Commissioner of Patents Attesting Officer