US2636325A - Valve seat reconditioning tool - Google Patents

Description

April 28, 1953 F. G. LIVINGSTON EIAL 2,536,325

VALVE SEAT RECONDITIONING TOOL Filed March 24, 1950 I Zia/avian? Patented Apr. 28 1953 VALVE SEAT RECONDITIONING TOOL Francis G. Livingston and Oren B. Hal-mes, Algona, Iowa, assignors to Livingston Tool 00., Algona, Iowa, a partnership Application March 24, 1950, Serial No. 151,666

1 Claim.

This invention relates to valve seat reconditioning tools.

Most valve seat reconditioning'tools which have been previously invented are adapted to recondition valve seats which are readily accessible. However, for many valve seats disposed in relatively inaccessible locations, such as those found in milk homogenizers, these tools are inadequate. For such valve seats special cutters have been utilized for the purpose of reforming the same. These special cutters are exceptionally expensive, are difiicult to use, and shorten the life of the machine substantially. Such tools require a skilled mechanic for their proper operation in order to be assured that the valve grinding job will be done properly and that the valveswill be correctly seated. In the case of homogenizers, for example, it is very important that the valves be properly seated in order to maintain the suction and discharge pressures needed to cause the machine to operate at rated capacity and to produce a product which will meet the specifications and requirements of the trade.

An object of our invention is to provide a valve seat reconditioning tool which will recondition the valve seat so as to provide it with a new but correctly inclined surface without cutting a new valve seat within the machine and thereby lengthening the useful life of the machine itself.

Another object is to provide a valve seat reconditioning tool which is capable of operation by an unskilled person without consequent injury tothe machine, and with assurance of efficient results.

A more specific object of our invention is to provide a valve seat reconditioning tool which has guiding and centering means which makes it impossible for the new-seat to be improperly formed.

Another object is to provide a valve seat reconditioning tool which will automatically insure that the new seat formed will have the desired angle of inclination.

A further object is to provide such a tool which obviates the use of lapping compound and its associated disadvantages and substitutes therefor an abrasive means capable of simple and ready attachment to, and detachment from, the tool.

These and other objects and advantages of our invention will more fully appear from the following description made in connection with the accompanying drawings, wherein like reference characters refer tosimilar parts throughout the several views and, in which:

Fig. 1 is a side elevational view of one embodiment of our invention in position for grinding the suction valve seat of a homogenizer;

Fig. 2 is a side elevational view of an embodiment of our invention in position for grinding the discharge valve seat of a similar homogenizer;

Fig. 3 is a vertical sectional view of the ref erence grinding head with its associated pilot, showing the abrasive sheet being held in position by the tapered nut;

Fig. 4 is a top plan view of the grinding head;

Fig. 5 is a vertical sectional view of the guide member;

Fig. 6 is a fragmentary side elevational view of the lower end of the revoluble driving shank with a portion broken away to show the attachment means thereof;

Fig. '7 is a side elevational view of a driving shank adapted for use with an electric driving drill in conjunction with the reference grinding head and its associated parts when grinding a suction valve seat; and

Fig. 8 is a side elevational view of a driving shank adapted for use in conjunction with an electric driving drill in conjunction with the reference grinding head and its associated parts when used to grind a discharge valve seat.

Fig. 9 is a plan view of one of the abrasive sheets used in conjunction with the grinding head.

One embodiment of-our invention is shown in Fig. 1 in position for grinding the suction valve seat [0 which is formed in the block II of a homogenizer H. As shownin' Figs. 1-8; the invention includes a reference grinding head 12 which is generally frusto-conical in shape and has, as shown, a hexagonally shaped recess l3 in its upper portion. Extending downwardly from the lower portion of the reference grinding head i2 is a cylindrical portion I4 whichhas external threads 55 formed thereon adjacent the grinding head [2 and which has a recess It in its lower end. This recess I6 is providedwith threads adapted to co-operate for threaded engagement with the thread of a screw bolt I1. Threaded onto the cylindrical portion M adjacent thehead I2 is atapered nut I 8. This tapered nut l8 has its tapered sides of exactly the same inclination as the inclination of the frusto-conical periphery of the reference grinding head l2. Carried by the cylindrical portion I4 is a freely rotatable pilot member is which is maintained in position below the tapered nut l8 by the screw bolt I1. This pilot member 53, as shown, is cylindrical and of dimensions to fit snugly within the bores 26 and 24 of the homogenizer H. An abrasive sheet 22 is annularly arranged around the frusto-conical periphery of the grinding head l2 in flush surrounding relation thereto.

The grinding head l2 may have its frusto-conical periphery formed at whatever angle of inclination is desired. For example, if the angle of inclination of the valve seat to be reconditioned was originally 45 degrees, then a reference grinding head 12 having a 45 degree angle to its frusto-conical periphery should be used to reoondition that particular valve seat. The reference grinding head I2 is used as a reference and the brasive sheet 22 assumes the same angle when arranged as shown in Fig. 3. The abrasive sheet 22 is formed by-cuttingthe -.same from a pattern which is obtained by splitting a cone of the desired angularity'and flattening the same upon a flat surface- The-abrasive sheet shown in Fig. 9 is a 45 degree angle sheet.

A revoluble drive shank -23- which-iscadapted to have torque applied thereto is utilized to provide the necessary driving power to cause-the reference grinding head 12 to turn relative to ithervalve seat'. to bezreconditioned. As shown r 1 this shank i 23 may. be in the formzof a speed-wrench. Therlower end .of' theshankfid gistprovidedwith airecess -24, -a small tension :sspringg.-25' andwa smallmetal ball 28--arranged as .wshow-n in Fig; 6. "The 'metalball 2e in-conjunction with the spring 25 provides -a'means for i-instant attachment.ondetachment of the sham: r23ato; .themeference grinding head 12 by way of the recess [3 of the head. The lower end of atheg'shankzfl ofycoursewmustbe of equal di- (mensionsto the dimensions of the recess [3 in the;upper portionof the reference-grindinghead 12. A frusto-conical guide-member 21 is proevid'ed for use in conjunction withthe shank 23L llVhen .it --is desired 130-. recondition" the 'sSllCtlOll =valve-; seat; lathe. device is arranged asshown in Fig. .1. -The:*reference grinding,head12 must .fi1fst.--be preparedeso :asto present -.an.= abrasive -surfacemo the. seat l .To do this.the..-tapered .rnut .18 is. loosenedhslightly with'theefingers and thebrasive. sheet-.2215 annularly arranged-about I -.the ifrusto-conical periphery of the reference cgr-inding head l2- in. flush surrounding. relation ,thereto. The tapered nut i8 is ,then tightened Jso, as; to hold ,the abrasive sheet 22 immovable 1 relative to the reference grinding head 12. .This isaccomplished-as the result of the tapered porutioneof ,thenut l8 being.- of exactly the same ..angle;as.the frusto-conical periphery. of the refmerencegrinding. head 12. The taperednut l8 ..,.clamps. the, lower edge. of theabrasive, sheetI22- nupwardlyagainst the, grinding head l2 andholds .the,.entire ,sheet 22 iniflushsurroundingnrela- Qtion since ,thesheet has beenaccurately formed t-tor'be of the exact. sizenecessaryjto suround the frustorconical peripheryv of the reference grinde ing headlz. l-Thereference grinding head, [2 is ,-."then .sli d through the-opening shown on the ,right hand side of Fig. l which is :open .be-

"ioause of the previous removal of the plunger port cover (not shown). Thereferencesgrind- 4 ing head 12 is dropped into position so that the pilot l9 fits into the bore 2!! of the homogenizer H. The pilot I9 serves as a centering device and provides a bearing for the reference grind- :3 ing head I2. This pilot [9 insures that the reference grinding head 12 is at all times correctly aligned relative to the valve seat It. The shank :123fzisvthen inserted through theopening 28 of the guide member 21 and then inserted from the top of the block ll of the homogenizer H down into attaching position with the reference grindinghead 12. The spring actuated metal ball 26 serves to retain the reference grinding head l2thereon, and the complementary hexagonal shapes of thelower end of the shank 23 and the recess i3 co-operate to enable an operator to..cause,the,;head I2 to turn relative to the seat ill by revolving the shank 23. While this operation is being performed the guiding memeo her 2? which, as shown, rests within the top :openingvof the block,- maintains the shank 23 and the reference grinding head I2 intrue: pc- :sitiorrrelativectothe. bore: This insures that .the: seat .-:afterit has been reconditioned: by re 5 "peatedi turning of r the reference grinding head ligand its abrasivefsheetrzil willhave the proper angle; .:.This; angle will be-the same-angle. found this seat when 'themachine'was'new. If .de- *sired,- the:shank 29 may be used in conjunction 3;)With an electric drivingdrill not 'shown) :in-

stead of the'shank 23. Thisris recommended, -however,' only -:whenthe-valve -seat- Hi is ex- 'tremelyiworn.

W hen; it is desired to recondition theidischarge valve: seat 3! :a similar-operation is performed with the: exception-that thepreferencez grinding head it and its r associated parts, i the 'pilot: I9, the rabrasive sheet-22, and-the nut 18, are dropped-into:--position from above, sothat the H pilot|9' vvill,'in conjunction with the-bore '21,

provide: the necessary centering 'for the: referencegrinding head l2 and a bearing in which it may turn. The guide :member This utilized tin: thersame :manner as describedabove. Again, ,za "differentishank such as the shank-30 maybe utilized in. conjunction witha power driving-drill insteadioftheshank23 if the seat 31: iS';8X- trem'ely-worn: The: operation .of reconditioning: the: discharge valve seat- 3 I .is-bestshow-n in .-Eig.';;2. v v '0ne""-advantage:of' our invention is thatit provides a grinding :head which canv be usedze as :a :reference'rmember upon which the abrasive may be applied which will insure the formation of 1 a 'reconditioned valve seat conforming in specifications to a new valve seat in new machine. The-re is'no excess loss' or shortening of Y the life of such'a machine such as is experienced with the cutting devices currently in use. It isreadi-ly'apparent that only a 'minimum of the block I l is removed in the operation.

Another advantage is thatj'our. device'may be operated lay-unskilled labor "without danger of a new valveseat being formed which is not prep- .erlyoriented relativerto the bores 29 and 2!.

:Our device is easy to use and simple to operate. It is impossible for even the most unskilled laborerto .prepare .a reconditioned valve .seat with. ourdevice does. not accurately conm iorn'i.to'thespecifications of valve seats found sheet eliminates loss-.of time that. might otherwise be involved. At the same time the use of such abrasive sheets 22 obviates the need of lapping compounds and the like and their accompanying disadvantages. The abrasive sheets 22, of course, may be of varied texture and of different shapes, depending upon the extent to which the valve seat to be reconditioned is worn and the original angle of inclination of that valve seat. The accurate reconditioning of such worn valve seats increases the efiiciency of the machine in that the suction and discharge pressures needed to cause the machine to operate at rated capacity and to produce a high quality product, are maintained.

It will, of course, be understood that various changes may be made in the form, details, arrangement, and proportions of the various parts without departure from the scope of the present invention, which, generally stated, consists in the matter shown, and described, and set forth in the appended claim.

What we claim is:

A valve seat reconditioning tool comprising a frusto-conical body having an uninterrupted generally frusto-oonical supporting surface and having a depending cylindrical portion, means at the upper end of said body for axially connecting said body with a revoluble driving shank, a cylindrical and rigid pilot member rotatably mounted on said lower cylindrical end portion of said body in close fitting encircling relation for free and unlimited rotation with respect thereto and extending coaxially thereof, said pilot member having an outside diameter equal to the inside diameter of the annular passage inwardly of the valve seat in a block for tight fitting engagement therewith to provide true and non-yieldin centering for said frusto-conical body and constituting a bearing for said body, said frusto-conical surface supporting a flexible, arcuately shaped abrasive sheet having a pair of free ends and of a length entirely surrounding said frusto-conical surface without overlap of its ends, and a single clamping member threadedly mounted on the lower cylindrical end portion of said body between said pilot member and said frusto-conical portion for quickly and easily detachably securing the abrasive sheet in flush surrounding relation with the frusto-conical surface of said body, said clamping member being capable of releasing the abrasive sheet without itself being disconnected from said body.

FRANCIS G. LIVINGSTON. OREN B. HARMES.

References Eited in the file of this patent UNITED STATES PATENTS Number Name Date 278,478 Wright et al May 29, 1883 1,734,548 Wacker et al Nov. 5, 1929 1,871,228 Stout et a1. Aug. 9, 1932 1,964,240 Beard 1 June 26, 1934 2,994,680 Beard Mar. 19, 1935 2,026,051 Love Dec. 31, 1935 2,935,299 Tyler June 29, 1937 2,106,201 Aab Jan. 25, 1938 2,133,612 Gallivan Oct. 18, 1938 2,142,595 Akans Jan. 3, 1939 2,400,160 Mizell May 1 1, 19416 2,454,068 Kuhlman Nov. 16, 1948

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