US3186713A

US3186713A - Bowling pin base

Info

Publication number: US3186713A
Application number: US50013A
Authority: US
Inventors: Hebble Keith Allen
Original assignee: AMF Inc
Current assignee: AMF Inc
Priority date: 1960-08-16
Filing date: 1960-08-16
Publication date: 1965-06-01
Anticipated expiration: 1982-06-01

Description

June 1, 1965 K. A. HEBBLE BOWLING PIN BASE 2 Sheets-Sheet 1 Filed Aug. 16, 1960 Fig. 4

. Fig. 6

INVENT KEITH HEB E Fig. 3

M a/M ATTORNEY 2 Sheets-Sheet 2 INVENTOR. KEITH HEBBLE ATTORNEY June 1965 K. A. HEBBLE BOWLING PIN BASE 'Filed Aug. 16, 1960 Fig. 9

United States Patent 3,186,713 BOWLZNG PEN IEASE Keith Allen Hebble, Arcade, N.Y., assignor to American lgdlachine 8: Foundry Company, a corporation of New ersey Filed Aug. 16, 1966, Ser. N 50,013 2 Claims. (Cl. 273-252) This invention relates to bowling pins and more particularly, to a novel improved durable base for bowling pins. A bowling pin is subjected to severe use from the battering of balls and other pins. One of the most pronounced areas of damage due to the striking (direct and rebound) of one pin against another and against the bowling alley, and from being hit by the ball, is the butt end, especially the edge portion of the pin base, i.e. the annular segment which forms a juncture between the side and bottom faces. rnercial pins are now equipped with a wear-resisting base of tough plastic or other durable composition. Many of the arrangements employed comprise a base piece placed in an undercut in the base and which encircles a projecting core or shank portion of the pin. The base is secured by any of a variety of mean such as screws, adhesives or numerous locking arrangements.

The difficulties of using base fittings known heretofore, resides in the cumbersome procedure needed to affix the base or in the difiicuity of providing an arrangement which dependably resists separation of the base piece from the butt of the pin. No known prior means for fastening bases of this type has thus been entirely satisfactory.

For example, screws require considerable time to afiix to die base and loosen with dimensional or other changes in the wood. Adhesives, if compatible initially with both the pin butt composition and the base insert, have not proven satisfactory in use, e.g. adhesive bonds require relatively long periods to apply, they are messy, require considerable curing times and also lose their adherence with dimensional changes of wood. Also these compositions oftentimes contain ingredients which are damaging to the plastic finish of the bowling pin.

In general the arrangement of the invention utilizes a main base piece easily inserted into the pin butt coupled with a locking ring of heat or chemically deformable material which when pressed home in abutting relationship to the main base piece seats itself in a circumferential locking groove in a manner securely holding not only itself but also the main base insert against removal or.

most effective use of available materials due to the problem encountered in securing these pieces. First of all, it is desirable to provide a base insert arrangement that is self-contained i.e. requires no adhesive, screws, etc. The use of press-fitted bases is known. The difficulty with this type arrangement in the past, however, has been the uncertainty of the locking arrangement between the pin body and base. The insert itself while durable is often of such composition that it does not suitably adapt to permanent deformation when inserted in the pin body so that it can be secured tightly and permanently in the pin body. Inserts of composition which do suitably conform, on the other hand, are often not those best suited to resist the wearing and chipping occasioned by the severe battering during normal use of bowling pins. {The present invention by employing a novel two piecestructure for the pinbase couples the most advantageous As a consequence, most co.l

Cal

features of the best materials available. The annular Patented June '1, 1965 'ice wearing area of the pin base may be formed ofdurable chip and dent resistant material having a permanently preformed contour, and the locking ring, which cooperates therewith and locks the wearing member, may be formed of material readily conformable and hardenable in situ to provide an extremely secure combined unit.

It is an object of the present invention to provide an inexpensive easily afiixed base of excellent durability. It is another object of the invention to provide a base of novel arrangement combining optimum properties, which afiords maximum durability, ease of afiixing to the bowling pin body and maximum security of the base against release from being struck. Other features and advantages of the invention will become apparent as the description provided hereinafter proceeds.

In the accompanying drawings:

FIG. 1 is a cross sectional view and shows the butt portion of a bowling pin with the two piece base of the invention secured in position therein.

FIG. 2 is a cross sectional view and shows the butt portion of a bowling pin with the main base piece in position and the locking ring prior to being press-fitted into locking position.

FIG. 3 is a cross sectional view of the butt portion of the pin showing the undercut without the base inserts.

FIG. 4 illustrates in a crosssectional view the annular base piece which forms the juncture of the side and bottom of the pin.

FIG. 5 shows in cross section a locking ring.

FIG. 6 is another cross sectional View of a pin butt portion illustrating a modified undercut.

FIG. 6a is a cross sectional view of a pin with the base in place utilizing the modified undercut arrange: ment of FIG. 6 with the base of FIG. 7 (slightly modilied) and the locking ring of FIG. 5. i

FIG. 7 shows in cross section a base piece employed with the pin embodiment illustrated in FIG. 6.

FIG. 8 illustrates in cross section still another alternate pin butt undercut. p

FIG. 9 illustrates the two piece base assembly employed in conjunction with the undercut shown in FIG. 8 prior to insertion in the pin butt.

FIG. 10 illustrates the arrangement of the base of FIG. 9 inserted in the butt'undercut of FIG. 8.

Referring in greater detail to the figures, the improved bowling pin, as provided in the invention, comprises a wooden body'l of usual shape with the butt comprising an undercut portion 2 forming a projecting cored. Abutting the core 4, a downwardly facing groove 5 isformed between a cylindrical wall 3 and the core 4. Near the upper extremity of the core 5, a locking groove 6 is provided.

As seen in FIGURES 1 and 2, the base insert 10 is positioned in the undercut and the skirt portion thereof forms an extension of the bowling pin'bottom 13 and side 14 at the juncture of the bottom surface and side surface of the pin. The base piece 10 is preferably formed of a durable impact and chip resistant material. Any of the commercially available resinous compositions having these properties such as nylon, isocyanate resins, polycarbonates, cellulose acetate butyrate, acet-al resin, marketed under the brand name Delr-in, ethyl cellulose, polyethylene, polypropylene, high-impact styrene-butadiene or styrene butadiene-acrylonitrile copolymers and the like may be'used. In affixing the base to the pin, more detail reference is made to FIGURES 3-5 of the drawing. In FIGURE 3, the butt of the pin is shown with the cut out configuration prior to the assembly of the base components to the pin. The undercut comprises an annular face portion 2, a downwardly'facing groove 5, the

projecting core 4 and the circumferential locking groove 6 formed in the core 4. In attaching the base of the intWo piece 7 polymer art for this urpose may be employed including various blends of suitable polymers of the type named hereinabove, e.g. ofolefins, vinyls, acrylics, styrenes, etc.

Prior to the insertion of the ring 17, the upper end 18 which is intended to enter the space formed between the core and the base piece is heated or chemically softened to increase its plasticity and fiowability and is inserted while substantially deformable. Suilicient pressure is applied to the bottom 19 of ring member 17 to force the opposite deformable end 18 thereof to conform and fill the contour of the locking groove 6. Aiding the deformation,-so that the end .18 of the locking ring forms a locking bead in the groove 6, is the upper endof the base 10 comprising the wedge portion 16. Upon cooling, or hardening thru chemical action, the tip 18 of the annular ring 17 retains its shape within the locking groove 6. Shown in detail in FIGURE 4 is the main base piece comprising a skirt portion forming a shoulder 11 which abuts the undercut shoulder 2 of the base and a collar portion 12. The integral wedge 16 directs thefdeformable tip 18 of the locking ring 17-into the locking groove 6. It

is thus .seen, in accordance with the invention, that the up-' per tip 18 only of the annular ring 17 is softened and only to the extent that it deforms when firmly press-fitted to fill the locking groove 6. The remainder of the locking ring 17 is kept relatively rigid as itis press-fitted into place. It should be noted that the preformed base 10 apart from the locking ring 17 does not require that it be heated or deformed in any manner in order to secure it in the butt of the pin. Because-the piece 10 in no way need be altered in its condition or shape, it may be formed of a material which is extremely durable, heat and/or chemically resistant and relatively inflexible, i.e. combining the optimum in desirable properties such as toughness, impact resistance, etc. be preformed from a thermosetting synthetic resin and set or hardened in a permanent shapewhich substantially precludes fiowability as distinguished from thermoplastic resins which soften under heat and harder upon cooling.

, Shown in FIGURES 6 and 7 is a modified embodiment wherein the base piece 20 comprises a skirt portion 21 and a collar portion 22 positioned in abutting relationship to the undercut of the pin in the manner described in connection with the base of FIG. 4; The base piece 20, shown in FIG. 7,'however,- has as an integral part thereof the head 23. The inside upper extremity of the collar portion of the unit inFlG. 7, it is' seen, is not shown with. V

the wedge arrangement designated 16 in FIG. 4. A struc ture of this kind, i.e, with an inner locking Wedge 26 (similarto 16 in FIG. 4) is. illustrated by-base 24 in the assembled arrangement of FIG. 6(a). rnentary undercut configuration for the pin butt is shown in FIG.-6 in which like parts are designated by the numerals employed in FIG. 3, comprising the pin body 1 It may, for, example,

The comple serted between the base member 211' and the core 4. Upon exertion of firm pressure the deformable plastic flows into the locking groove 6. The direction of flow may be aided by a suitable wedge arrangement such as that shown as 16 in the unit of FIG. 4.

Referring'to the modification illustrated in FIGS. 8-10, a pin:base 39 comprising a .skirt portion 31 and collar portion 32 is assembled with a locking ring 35 of substantially the same configuration as the locking ring 17, and inserted into the undercut of the pin 1. The bottom .37 of the locking ring 35 abuts the inwardly extending shoulder 33 of the portion forming the bottom of base 35. Prior to assembling therein theupper portion 36 of the locking ring 35 is softened by heating or by suitable chemical treatment so thatit flows under pressure. The two piece assembly as a unit is then inserted into'the pin undercut so that the plastic locking ring flows into the locking groove 34 formed in the inner periphery and near thetop of base collar 32. In a like manner and at the same time, the upper portion 36.0f the locking ring, in a flowable conditiornfiows into the locking annular groove 39 formed at the top and in the shank portion 4 of the pin 'butt.- It will be apparent that the locking groove 37 may be situated, if desired, at a lower position but near the top of the shank 4. In the arrangement illustrated, the locking ring 35 is preferably made of a lower melting composition so thatthe two members may be, if desired, first assembled. and upon heating the top 36 of the locking ring will be softened. to a fiowable state but the top of collar 32 will remain rigid. Thereafter the unit is inserted into the pin butt and pressed with suitable pressure with the undercut forming projecting core 4, the d0WI1- wardly facing groove designated 25 and the second or outer locking groove complementing the bead 23 in the base piece 20 designated as 28. In securing the base 20 of FIG. 7 or the base-24 of FIG. 6(a) into theundercut, the base is inserted into, the undercut. of the base in abutting relationship in'the manner described in connec to effect flow of the plastic material into the

grooves

34 and 3?. Increased plasticity of the upper extremity 36 of the locking ring may be effected by chemical treatment thereof employing, where the

units

30 and 35 are assembled, a chemical softening agent substantially innocuous to the rigidity of the composition of which base 30 is formed- J Each of the tWo members of the base insert is preferably prefabricated to produce a snug fit. Generally the members are sized so that the inside diameter of the locking ring is several mils (i.e. about2-15 mils) smaller than the outside diameter of the core or shank inthe pin butt; the outside diameter of the locking ring member several'mils larger than the inside diameter of the units it), 2% or 36 irrespective of the. wedge portion when er-ably slightly greater than the vertical distance from the bottom of the pin to the top shank or core formed in the pin butt sothat upon press-fitting and locking a flush V arrangement results, However, where desired, the bottomof the inserted locking ring may be recessed from the bottom of the pin base. The preferred arrangement allows for the deformed portion of'the ring taken up in filling the lockinggroove 6 and still permits the bottom of the ring 17 to be flush with the pin bottom. In the undercut arrangement of FIG. 10, the locking ring 35-must be of appropriate length to allow for the flow of resin into the locking

grooves

34 and 37. V

' While the present invention is illustrated and described in connection with a specific arrangement, it should be understood that the invention is not limited precisely to the structure illustrated and described but includes modifications that are obvious to one skilled in the art in the light of the inventive improvement herein provided.

I claimr' p 1. A bowling pin having its buttend provided with an undercut at the juncture of the bottom surfaceand the side surface of the pin forming thereby an outwardly projecting central core, said undercut extending into the body of the pin adjacent said core forming a downwardly :facing annular groove, a circumferential locking groove in said central core, an annular base of Wear resistant material in said undercut, said base comprising an annular skirt portion .forming the junction for the bottom and side of the pin and, integral with said skirt portion, an upright collar portion encircling said core and extending into said annular groove and a deformed inner cylindrical ring member positioned between said core and said annular base and forming at the inner extremity thereof a rigid locking bead in said circumferential locking groove, said base being further provided with a shoulder beneath and abutting the bottom of the inner cylindrical member.

2. A bowling pin having its butt end provided with an undercut at the juncture of the bottom surface and the side surface of the pin forming thereby an outwardly projecting central core, said undercut extending into the body of the pin adjacent said core forming a downwardly facing annular groove, a circumferential locking groove in said central core, an annular base of wear resistant material in said undercut, said base comprising an annular skirt portion forming the junction for the bott-om and side of the pin and, integral with said skirt portion, an up- 6 1 right collar portion encircling said core, said collar portion provided with an an integral locking Wedge inside said collar at the upper extremity thereof, and a deformed inner ring member positioned between said core and said annular base and forming, at the inner extremity thereof a rigid locking head in said circumferential locking groove, the upper end of said locking ring engaging the locking wedge of the collar portion and being deformed thereby into said circumferential locking groove.

References Qited by the Examiner UNITED STATES PATENTS 1,580,688 4/26 Sheldon 273-82 1,585,123 5/26 Sheldon 273-82 1,718,309 *6/29 Sheldon 273-82 2,680,023 6/54 'Elli 273-82 2,809,038 10/57 Scheidemantel et a1 273-82 2,814,835 12/57 Faulkner 273-82 X 2,964,319 12/ Berry et a1. 273-82 RICHARD C, PINKHAM, Primary Examiner. ELLIS E. FULLER, JAMES W. LOVE, Examiners.

Claims

2. A BOWLING PIN HAVING ITS BUTT END PROVIDED WITH AN UNDERCUT AT THE JUNCTION OF THE BOTTOM SURFACE AND THE SIDE SURFACE OF THE PIN FORMING THEREBY AN OUTWARDLY PROJECTING CENTRAL CORE, SAID UNDERCUT EXTENDING INTO THE BODY OF THE PIN ADJACENT SAID CORE FORMING A DOWNWARDLY FACING ANNULAR GROOVE, A CIRCUMFERENTIAL LOCKING GROOVE IN SAID CENTRAL CORE, AN ANNULAR BASE OF WEAR RESISTANT MATERIAL IN SAID UNDERCUT, SAID BASE COMPRISING AN ANNULAR SKIRT PORTION FORMING THE JUNCTION FOR THE BOTTOM AND SIDE OF THE PIN AND, INTEGRAL WITH SAID SKIRT PORTION, AND UPRIGHT COLLAR PORTION ENCIRCLING SAID CORE, SAID COLLAR PORTION PROVIDED WITH AN INTEGRAL LOCKING WEDGE INSIDE SAID COLLAR AT THE UPPER EXTREMITY THEREOF, AND A DEFORMED INNER RING MEMBER POSITIONED BETWEEN SAID CORE AND SAID ANNULAR BASE AND FORMING, AT THE INNER EXTREMITY THEREOF A RIGID LOCKING BEAD IN SAID CIRCUMFERENTIAL LOCKING GROOVE, THE UPPER END OF SAID LOCKING RING ENGAGING THE LOCKING WEDGE OF THE COLLAR PORTION AND BEING DEFORMED THEREBY INTO SAID CIRCUMFERENTIAL LOCKING GROOVE.