US2482190A - Finger hole insert for bowling balls - Google Patents

Description

Patented Sept. 20, 1949 UNITED ISTATES PATENT OFFICE 'Herman J. Kramer, Cleveland, `Ohio, -assignorfof 'one-half to AEugene J. @Reardon Application February 19, 1945, ,Serial N o. 578,571

1-6 Claims.

This invention relates to a bowling 'ball having .finger holesand more particularly to an improved .finger vgripping means for the finger holes thereof.

The usual bowling k,ball is provided with two or moreholesone .forthe thumb and the other holes for :other fingers of vthe hand. These holes are provided sothattheball y may be held in onehand of .the player when howling and so that the vball while in motion in the `players hand .may .be controlledby the player until released at the proper time for delivery. These holes are all drilled, Whether radially or convergingly to a pointaboye the ball center to vprovide a sufficient angle so that the players fingers can grip, retain ,and control the ball.

For the sake of safety, comfort, yconsistencl7 in yplaying 'and good scoring 4it "is desirable that the holes provided in the ball properly Yfit the playerfs hand and -fingers. The fit around the thumb should be just loose enough `for comfort and tight enough to maintain friction or grip when the thumb `is ,bent at the joint and pulled out of the hole upon delivery vof the ball. The holes for 'the other iingers should Jiit Vwith the same degree of looseness. When 4the 'holes are too large it isdiflicult 'to hold the -ball properly; When too small, the fingers of the -player soon become irritated, torn and scraped because the fingers have a Ltendency to lexpand after a `few balls Ahave vbeen rolled. "Tight or small finger holes prevent -the 4release of -the ball correctly and easily. They cause y'the 'ball to cling to the fingers `too long at `the time of delivery, thus eitherreversing or hooking the yball unnaturally.

In order to'elimina-te the -tendencyforithe Aball to Yslip out of the -players hands lprematurely various expediences have 'been resorted zto such as vthe use of chalk land other sticky materials, and Iby providing liners for the holes made -of compressible and yieldable material-such as cork, soft 'rubber or other resilient material. It has also been suggested to corrugate the Yinside surfaces of Athe holes, lto otherwise 1roughenthe -wall surfaces thereof, -and to provide inserted hard liners lhaving rough lareas all to -provide frictonal ,gripping -means iWhile lthese suggestions have provided a certain degree of friction for gripping purposes 'they have also Apresented -the undesired ,friction 'that has resulted kin abrasion and soreness of the fingers. VlEn an attempt to overcome thesedifliculties it has Vbeen suggested to provide a wall structure for `the vholes Yin which eiectivefinger gripping was made possible -while the friction was either minimized or eliminated,

2 this having been accomplished by forming the holes so that the entrant end region was hard, smooth `and frictionless and the wall at `the inner region was compressible and-resilient.

While these suggestions have been partially Successful 'theyhave lfailed to vprovide the desired gripping action of the fingers inthe holes of the ball, rthey have failed to provide during extended periods of playing 'time the necessary smoothness -and frictionless passage to the withdrawing ,ngers of the yplayer when playing, fand they have failed 'to provide Ithe exacting 'lit for the players hand and .fingers desirable for the safety, and comfort of vthe player as well as Ito efiect-,consistencyiin playing and good scoring.

Nature has provided vthe skin on 'the inner surface ,of .thehands and lingers with numerous ridges and depressions ,arranged kin various patterns and on the tops of the ridges are located the voutlets ormouths .of small ducts which :permit the disch-arge `of moisture onto the hands and ngers. These ,patterned yridges and depressions give 4the .fingers a fine sense of touch and also provide a suction between the surface of the fingers .and ,the article `contacted to thereby enable the hands and ngers to more securely grip the article .whenit is held in the hand.

Itis customary Vwhen holding a'ball with finger holes in 1playing to insert the lfingers into the holes :so that the 3rd and 2nd-and in some cases aportion of the 1st lphalangesof the lingers are in the holes. In thus yinserting the fingers in theapplicationof myinvention take full advantage of naturesgprovision of suction created vby the `alterna-te ridges and depressions in the surface .of theskin ofthe players fingers for holding the ball by providing inserts for .the finger holes, of-sthehallmadeqof grnaterial which is nondeformable vat temperatures Vto which `the ball may befsubjeoted in playing rand having the surface to `be contacted by the playerfs fingers formed `With1-aicontour lconforming to ,the shape of the individual fingers of the player. Thus each portion of .the players fingers is afforded an opportunity .of serving the function which nature .has provided thereby ,distributing ythe weight and force resulting .from the momentum of the moving ball .uniformly to all the surface portions -of the players fingers which are gripping lthe ball vvthereby `affording greater ease in playing and controlling the Amovement of the sphere as it 'is released, and -at `the same time providing a lsmoothness and frictionlesspassage to Lthe withdrawing 4fingers which will result :in

a minimum wear and tear of the skin of the fingers over extended periods of playing time.

It is one of the objects of my invention toY in the holes of any standard bowling ball in common use.

To the accomplishment of the foregoing and such other objects as may hereinafter appear, the invention further consists in the structural combinations hereinafter sought to be defined in the claims and described more in detail hereinbelow in connection with the appended drawing, in which:

Fig. 1 is a View of a portion of a bowling ball partly shown in section and disclosing the improved iinger hole gripping means of my present invention and the manner of its use.

Fig. 2 is a plan View of a blank used in making the pattern of the individualized finger grip 'insert of the invention.

Fig. 3 is a side View of the blank shown in Fig. 2.

Fig. 4 is a plan View of the pattern used |in making the individualized fing-er grip insert of the invention. v

Fig. 5 is a side View of the pattern shown in Fig. 4. V

Fig. 6 is a plan view of the individualized finger grip insert of the invention.

Fig. 7 is a side View of the individualized finger grip insert shown in Fig. 6. v

Fig. 8 is an enlarged view of a portion of a bowling ball partly shown in section and disclosing one of the finger holes shown in Fig. 1 with one of the individualized finger grip vinserts shown cemented in place in the finger hole thereof.

Fig. 9 is a cross-sectional view taken on line 9 9 of Fig. 8.

Referring now more in detail to the drawing, the bowling ball embodying my invention comprises the usual bowling ball I0 customarily made of hard rubber or a synthetic resin and provided with bored or drilled finger holes I I arranged convergingly as shown to present a sufcient angle so that the players lingers may grip, retain and control the ball. While only two holes are shown drilled in the bowling ball, three or more holes may be provided as desired by the player.

To accomplish the object of the invention, one or more of the holes II is provided with a finger contacting wall surface so designed that effective finger gripping is made possible whereby the players fingers will be able to properly grip, re-v tain and control the ball.

In forming the finger contacting wall surfaces of the finger holes, patterns of the players fingers are rst made having the finger contacting surfaces formed with the same Ycontour as the surfaces of the individual fingers of the player. A mold of the pattern may ther-eafter be made in suitable molding material into which'may be cast a n'ished insert.

To make the pattern a plug I2 is provided made preferably of soft wax and formed by heating to a shape somewhat as shown in'Fig. 3 havforming ofthe pattern for only one iinger holeY ing a cylindrical portion I3 and an extended arcuate shank I4 of a size that will iit into one of the finger holes II so as to extend from the bottom of the hole to the surface of the ball. With a form of blank as shown in Figs. 2 and 3 a pattern and cast of the same can be made which will provid-e a bottom to fit the end of each of the fingers of the player which is inserted in the finger hole of the ball and a shank which will occupy substantially only that portion of the finger hole which will be lcontacted by the inside surface of each of the players fingers thus leaving the remainder of the cylindrical portion of -the'hole'free'to afford the necessary looseness t0 prevent the players lingers from sticking in the holes upon delivery of the ball when playing. The wax plug is preferably a type of wax which f may be readily softened by heating without be- I and capable of hardening after it is formed s0 Per cent Carnauba 25 Ceresin v10 Paraiiin 60 Beeswax 5 While soft wax has been specifically described other .types of yi-eldable material having similar characteristics may be used with equally satis-y factory results such as plastics particularly synthetic resins.

In forming the pattern for the insert the holev II is first lubricated so as to permit the pattern to be readily removed after it has been formed, after which the wax plug is softened slightly by heating and is inserted into the lubricated hole so that the shank portion I4 will be positioned ad jacent the side I5 thereof as indicated inFig. l. Thereupon one of the fingers, the contour of which is toY be formed in the wax is inserted in the hole I I in the position in which the ball is to be gripped when playing and the ball is gripped so as to press the linger into the soft wax of the plug thereby forming an impression in the wax havingthe contour of the end and inside surface of the players finger and vsqueezing the excess wax from the hole. The formed wax pattern is then removed from the hole and any excess wax is trimmed from the pattern. .If desired the wax pattern may be softened by reheating and maybe inserted again into the finger hole whereupon the player may again grip the ball and'swing it as he would when playingY to thereby forma better and more accurate impression of the finger. The formed wax may if preferred'be removed and reheatedA a third time/to soften and be inserted in the lubricated-hole a third time and may be further compressed by inserting the linger in the hole, and by again gripping and swinging the ball and releasing it in the act of playing. VWhile the has been described, similar patterns may be madel for the other finger holes preferably at the same time so that surface contours will be formed in the patterns with the fingers inserted fully into finger so'v that when. the ball isi liftedand swung by the player there will be substan tiaily open' space between the portion l5 of the players'l hand' 4and surface -of theball as shown in Fig. l. 'By thus fitting the fingers in thepatter-nin the linger holes with the hand touching the surface of the ball practically no variation ,in the pitch Aor span .of the-playershand will be possible. -With theA ball thus fitted to the hand. the player will be: able to grip and lhold .the l0 of .the above twoy types'y which will be suitable for ball. without prematurely dropping it and a formi-ng the ngerhole inserts of the invention smooth` delivery with Aperfect control of the ball` are asl follows:`

result Thermoset plastics After thus forming the wax a pattern for an insert will be obtained as shown in Figs. 4 and 5 15 having the exact contour of the players Athumb 1 or' linger. The wax pattern is' then removed from 'Vllcenitc metal Sinthetie resins the .1i-cies and aninsert isy .formed m the following led mamie manner. The lwax pattern is imbedded in the .I lower 'half of a vulcanizing ask which may be a go (Bkeult mypel lmyptlal lyel type such as commonly used in making denture 'v eno-Ormas were D t Sie basel materials, and is thereupon surrounded by letlil alslirglgog? plaster or artificial stone. One particular type of A artificial 'stone which may be used for casting Glycine such as contemplated in making the inserts of Thefmhte" TSLLLIU 1 L.

Cellulose products lSynthetic resins Glass Celluloidtype Cellulose Vinyl resin Polysyrol Aralkylhalide Acrylate type (cellulose acetates type (polytype (poly.- type (benzyl (polymerired nitrates) mex-ized vinyl ymerized st-ychloride acrylic acld) esters) rene) napthalene condensation products) my invention i's known asA quick setting stonen and The various types of plastics mentioned have may have the following approximateV analysis: been listed as someV examples of material suitable Per cent 1J for; rinaling th inerts lof -invention ailtare no o e cons rue as imi a ions as 1n a 1 ion srllee 1 to these resins there .are a number of other prod- Pgment' ""'K 50 ucts that have excellent vproperties that make P1 a Ster "r'lajiner l them suitable for use in making the inserts. 45- Urea-formaldehyde and styrol compounds have Other -casti-ngstcnes may also be used such as anmany desirable qualities as well as the polyindine hydrite Stonev which' iS formed by calcin'ing gypcompounds. The petroleum resins may also be sum and plaster-Cement Stones, Which are plaster used. It is desirable in a plastic to be used as an mixed with alum, sand, cement, and citric acid. insert of the invention that it be chemically A Separating medium is applied on the plaster and 5o" stable at the temperatures at which it is moldable. the wax pattern in the lower half of the flask. It is also a requisite of the plastic that in the After the plaster has hardened then the upper vulcanized or cured state it be hard, strong, tough, half of the flask. is placed in position above the durable, physically and chemically stable and be lower half, and filledl with plaster or Stone. After insoluble in water and in perspiration from the the final set ofthe plaster material has occurred 55 plgyers. hand and ngerg A150 it Shomd take the halves are separated, and the wax is melted and retain a, polish, and'iiushed out with hot water leaving a mold of Thesurface hardness .of the thermos@ plastics. the desired insert. This mold cavity is then contemplated as coming Within the scope of the packed. with the material which is to be used in invention may vary from 13 to 27 kilograms per making the required insert after which the packed G0 square millimeter as measured by the Knoop inmaterial is vulcanized or cured by the applicadentation method andthe impactstrength may tion 0f heat 01 heat and Pressure depending 'upon vary from 2 to .4,3 centimeter-kilograms per cubic the type of material used. centimeter. The surface hardness of the thermo- In forming the finger hole inserts according plastic materials suitable for use in the invento the invention I preferably use plastic material 05 tion may vary from 10 to 22 kilograms per square which may be .either a thermoset or thermoplastic millimeter as measured'by the same method and type. Thermoset plasticsl are 'those substances the impact strengthtcf such materials may vary which changechemically'while being 'subjected to from 8 to 109 centimeter-kilograms per cubic heat. Thermoset resins are those which although centimeter. softened rby' the initial application of heat are 70` 'The containers in which the models or patterns permanently hardened Vby continued heating and are' imbedded, and to which repeated reference are thereafter no longercapable of being softened has already been made, are called flasks. These by reheatin-g. Ihermoset plastic bases are placed are made'in various shapes and types; some have inthemold-.in a plastic or granular state. Very bolts-to hold the liask parts together during vullittle vpressure is used-` to effect closure of the ilask 7 5- c-aniza'tion, others have the partsV held together 7 byfspring clamps or a compress. A bench pressV is used'in closing theiiasks after they are filledY with the molding plastenand also when the rubber or-other material to be vulcanized yor cured is vsubjected to heating.

I have successfully used inY making inserts according to the invention vulcanite also known as ebonite `or hard rubber which is a thermoset material and which isv fabricated by the chemical reaction between sulfur and rubber. One form ofvulcarlite in comnfioll` use which is applicable in making an insert of the invention A, has the following analysis:

Per cent Raw rubber Y 62 Sulfur l 29 Inert material 9 If desired I mayv form the insert with vulcanite having a condensite facing.

This material may then be cast to form th insert by packingT in a conventional mold and vulcanized by the application of heat. After packing and vulcanizing the inserts are then finished by polishing or .otherwise so as to accurately fit into the finger holes. When finished the inserts are placed in the nger holes of the ball and after they have been placed in the exact position determined by inserting the thumb and fingers into the holes the inserts are then permanently cemented in place. If desired a vertical slot ll may be provided in the finger holes and the wax patterns and cast inserts formed with tongues I8 to nt the same so that when the finished inserts are placed in the finger holes they will be positioned to fit the'players lingers when playing. Figs. 6 and 7 show plan and side views, the latter partly in cross section of the cast insert before it is cemented in place in the nger hole of a ball. Thus finished inserts are formed and secured into playing position in the finger holes l of the ball as shown in Fig. 1 having vbottom portions I9 and shank portions 2li conforming to the shape of the finger holes ll and individualized surface portions 2|, 22 and 23 conforming to the surface contours of the 1st, 2nd and 3rd phalanges respectively of the players lingers inserted into the finger holes when playing the ball. Due to the fact that no two persons have ngers of exactly the same shape and with the same impressions every insert made and used according to my invention will have a different finger contacting surface than every other insert. In other words every insert will be custom builtin the sense that it will be made or done to order as custom clothes ,or custom work. These inserts, if made of plastic material, will have when cured a hardness to maintain the shape of the inserts as cast including the individualized surfaces of the inserts and these surfaces will be maintained until they become worn in use and have to be replaced or repaired. Y

While the inserts of the invention have been described as secured permanently in place I may if preferred secure them in the finger holes by means of a cement which can be softened by the application of a little heat so that they can be removed and later secured in the nger holes of other balls which will preferably have the nger holes drilled so as to fit the span of the players handr Other means for securing the insei-ts in the finger holes, either with or without cement, may also be used, such as, threads in the holes and on the inserts, or spring-actuated bayonet type connections both of which are well which would be processed and Acast into molds toY form inserts andbe. vulcanized in much the same manner as vulcanite. Such other rubber vcompounds applicable in -carrying out the inventionV are olive base rubber, metal lled rubber, maroon rubber, pink veneer rubber, and pink rubber.

In the application of the phenol-formaldehyde condensation product type of resinl which is also al thermoset type of plastic to. the invention I preferably use the intermediate products of the reactions of phenol andV formaldehyderesin.VV If this mass is heated (approximately 140 C. forV one-halfrhour) a solid mass results on cooling which maybe used in sheet form, as a powder,'0r ina cakezform. This Vmaterial in sheet form is packedin a vulcanizing ask in the same manner as vulcanite and subsequentlyheated to formthe j completed yresin insert.V If the cake Vforml is used it maybe ground to a powder just before-use. After the Wax is removed from the vmatrix or mold,and both halves of the flask are thoroughly 1 cleaned, they are placed into a shallow pan of boiling water so as to heat the plaster mold. It takes from l5 to 20 minutes for the heat to Vpenetrate the investment plaster.

The following description covering the procedure for manipulating and curing the phenolformaldehyde resins can with certain modifications be employedwhen using any of the thermoset resins belonging to this particular group of synthetic compounds.

While the flask halves are heating, the material when a cake form is used is ground in an unglazed mortar by a pestle to the neness of coarse salt. After the matrix ormold has beenV properly heated it is ushed with acetone, drained and dried by wiping with cotton or cloth. While the matrix or mold is still warm some of the resin is poured from a spoon into the mold and spread and packed in.Y The heat of the Amold Causes the resin to fusequickly Yand it should be,

immediately compressed by pressing and tamping with apacking instrumentl- Additional resin is added and condensed by repeated tamping. Con#A siderableforce can now be used without danger. When the walls of the mold are covered'to the desired depth and thickness, the resin is again tamped until the entire mass is melted 0r fused.

The cast portion ofthe mold is now taken from the boiling water and similarly packed with resin a su'icient amount being used to insure the filling of the mold. Both sides of the pack 'must be thoroughly melted. Thetwo flasks are brought together and placed inacompress or hand press andpslowly closed. Any excess resin used will 0 escape during the closure ofthe flask or during the early stages of the cure when it becomes highly fluid.

In the application of the thermo-plastics to thexinvention IV may use some of the cellulose products such as manufactured from wood or compound inserts are characterizedY by a lower'- tensile strengthl lowerproportional 1imit larger i 9 set' andy greater deflectionwhen heated: under pressure, and' hence would probably be subject to greaterl distortion. inusethan the other plastic materials.

Intheapplication-ofthe synthetic resins to the invention I may use the-vinyl' resinsA which` are the derivativesy of ethylene pelymerizedlto form resins such. as-polystyrene resin.

I may also use the polyvinylv copolymers namely `the combination resin of.` polyvinylv acetate` and polyvinyl chloride which have been copolymerized tothe combined form. These -copolymer resins are-also thermoplastic in nature and the plasticity maybe governed by. the vinyl chloride-acetate ratio. In practice approximately 85 to-87 percent of monomeric vinyl chloride may beused.

In the further application of the synthetic resins to the invention I may use one or more of the acrylic resins which also are derivatives of ethylene although specifically polymers of acrylic acid, methacrylic acid or certain esters of these acids; Among these may be included methyl methacrylate` resins which are extremely stable and have excellent aging properties, and polymethyl methacrylate resin. While these resins maybe molded-asthermoplastics they are generally furnished in powder form and are mixed with a liquid plasticizer in the proper proportions just before they are tofbe packed into-.thevulcanizing flask for curing. By classification, the resins are thermoset during the early stages of polymerization, but as the reaction progresses, a thermoplastic softening takes place. As. the reaction:v continues-the mass becomes more rigid until at the endg of the cure a solidmass results, provided the curing temperature is below the softening point of the resin. The soft material ispacked into a warm mold and the flask is closed under pressure. Curingv can be accomplished'l either in boiling water or in a vulcanizer.

In processing inserts out of acrylic resins. the same procedure of casting ofA the phenol-formaldehyde lresins applies to these resins. This type of resin is put up in two different forms which will be described separately.-

All claims made areto the effect that' the-material is stronger than vulcanite, that it possesses complete stability and does not warp. It adheres well to metals and is easy to pack in the mold and to process both in making new inserts and in repairs.

As supplied for use the material is fully cured. In one form it is made up in sheets and the methods for using them are fully described and illustrated in the instruction sheetV accompanying each package of material.

The sheets may be packed in the conventional flask type mold to which heat and moderate pressure may be applied if desired to form the inserts, the heat being added merely to hasten the hardening of the inserts which, however, can be hardenecl at room temperature if allowed to remain in the closed flasks for several days. When cooled or hardened the inserts may be removed from the flasks and trimmed and polished like inserts of vulcanite or other resins.

The other form of acrylic resin which has been referred to is supplied in the form of a granular preparation and a liquid solvent. The same preparation of the mold is made and when the cast is ready to be packed the solvent is added to a desired amount of the granular material.

The mixture may be packed in the conventional flask type of mold which may then be hardened by the application of heat. After cooling the inl@ sertV may be polished and finished in the same manner as other acrylic resins.

While onlya general description of some methods and apparatus for casting the inserts of the invention out of plastic materials havefbeen presented it is believed a suicient description has been made to enable anyone skilled in thel art to carry out the invention. If more detailed descriptions of any specific apparatus or vulcanizing orcuringtechnique are desiredcomplete descriptions thereof may be found in the CompleteDenture-Prosthesis by R. O. Schlosser, published in 1939.

It is also within the scope of: the invention to form the inserts ofi either ferrous or non-ferrous metals and metal alloys. Thesev may be made by casting or by. swaging wrought metal into the desired form. Some such metals are cast alumi.- num, alloys of chromium, molybdenum and cobalt. For such. metals casting temperatures well over- 2200 F. are necessary and molding flasks and;y material suchY as-.used in conventional metal foundry practice mustl necessarily be used in casting theinserts.V After the inserts have been cast they may preferably be sand or shot blasted. to remove the surface roughness and subsequently ground and polished.

I may also form the inserts of stainless steel which may be swaged to the desired shape.` Various metals such as non-ferrous metals may be deposited electrolytically directly t0 the surface of a cast or model of the insert thus givingan excellent adaptation. The metallic bases have, the great advantage ofv high strength and wear resistance and are very sanitary. I may also overlay or coat especially theflnger contacting surfaces of the metallic insertswith a non-metallic coating such as synthetic resin, or a porcelain or baked enamel.

The individualized, finger grip for a bowling ball of my present invention, the manner of making the same, andthe advantages in use willin the main be fully apparent from the above-detailed description of the same. It will beA further apparent that changes maybe made inthe constructionthereof and` in the arrangement of the Darts, without. departing from thev principlesof` the invention as aboveset forth or as defined in the following claims.

I claim:

1. An elongated preformed insert for the finger hole of a bowling ball, said insert having a semicylindrical body portion with its outside surface adapted to t the wall of the said linger hole and its inside surface provided with at least two adjacent curvilinearly concave portions arranged tandem and extending from one end of the insert. the two innermost of the said adjacent concave portions conforming respectively to the surface contours of the inside halves of the medial and distal phalanges of the players finger which is inserted with the said insert in the Said finger hole when playing the ball.

2. An elongated preformed insert for the nger hole of a bowling ball, said insert having a cylindrical end portion and a substantially Semicylindrical shank portion longer than the said end portion, said insert having its outside surface adapted to t the :bottom and wall of the said linger hole and its inside surface provided with at least two adjacent curvilinearly concave portions arranged tandem and extending inwardly from the end of the insert opposite the cylindrical end. portion, the two innermost of the said adjacent concave portions conforming respectively Vto `the surface contours` of the inside halves of the medial and distal phalanges of the players linger which is inserted with the said insert in thesaid linger hole when playing the ball, the inside surface of the innermost concave portion continuing curvilinearly into the said Vcylindrical end portion of the insert.

3.The article of claim v1 in which the insert is made of a plastic material.

4. The article of claim 1 in which the insert is made of a thermo-plastic material.

5. The article of claim 1 in which the insert is made of a thermo-plastic material havingV in the cured state a hardness greater `than 9 kilograms per square millimeter as measured by the Knoop indentation method.

' 6. The article of olaim.2 in which the insert is made of a plastic material.

7. The article of claim '2 in which the insert is made of a thermo-plastic'material.

8. The article of claim 2 in which the insert is made of a thermo-plastic material having in the cured state a hardnessl greater than 9 kilo- Vgrams per square millimeter as measured by the Knoop indentation method.

9. The article of claim 1 in which the insert is made of a thermo-set plastic material. i

10- The article of claim 1 in which the insert is made of a thermo-set plastic material having in thecured state a hardness greater than 12 kilograms per square millimeter as measured by the Knoop indentation method.

11. The article of claim 2 in which'the insert is made of a thermo-set plastic material.'

12. The article of claim 2 inl which the'insert is made of a thermo-set plastic material having in the cured state a hardness greater than 12 kilograms per square millimeter as measured by the Knoop indentation method. Y

13. The `article of claim 1 in which the insert is made of metal. l

14. The artid@ of Claim 2 in which the insert is made of metal.

15. An elongated preformed insert for the nger hole of a bowling ball, said insert having an elongated body portion with its outside surface adapted to fit the wall of the said linger hole and its inside surface provided with at least two Yadjacent curvilinearly concave portions arranged tandem and extending from one end of the insert, the two innermost of the said adjacent concave portions conforming respectively to the surface contours of the inside halves of the medial and distal phalanges of the players linger which is inserted with the said insert in the said linger hole when playing the ball.

16. An elongated preformed insert for the linger hole of a bowling ball havinga slot therein, said insert havingr'an elongated portionwith its outside surface adapted to lit the wall'of thesaid linger hole, said outside surface having a tongue portion extending outwardly therefrom and adapted to lit the slot in the linger hole of the ball and having its inside surface provided with at least two adjacent'curvilinearly concave portions Larranged tandem and extending from one end of theinsert, the two innermost of the said adjacent concave portions conforming respectively to the surface contours of the inside halves ofthe medial and distal phalanges of the players finger Vwhich is inserted with Ithe said insert in the said linger hole when playing theiball.

HERMAN J. KRAMER.

REFERENCES CITED The following references areof record in the lile ofY this patent:

l UNITED STATESPATENTS Y Number Date I Name Y44:7,011 Harman V i Feb. 24, 1891 I520,898 Rodman June-5,rl894 626,584 Wilmerling 1- June 6, 1899 '673,688 Pickett May 7, 1901 v950,838 A Cavanagh Y Mar. 1, 1910 1,310,768 Nugent July 22, 1919 1,822,285 Hagman l e Sept. 8, 1931 2,119,590 MacDonald June 7, 1938 2,273,199 Hilton et al. Feb 17, 1942 FOREIGN PATENTS Number Country Date 19,182 f Holland Oct.1'6,'1923

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