US2618481A - Laminated bowling pin - Google Patents

Description

Nov. 18, 1952 Q D DQSKER 2,618,481

LAMINATED BOWLING PIN Filed April 30, 1948 y I. MMM

' JNVENToR. coRNEL/vs a. Doskue ATTORNEY Patented Nov. 18, 1952 LBHNTED BOWLING PIN Cornelius-.D.Dosker, Louisville, Ky., assignorto Garable-lirothers, Louisville, Ky., a corporation Y otKentucliy Assurance Apnio, 194e, serial N6. .a4-,riep

'Y 1 Thislmzentionzitel'ates,1to1new; improyedxbowie ine'uns'll l Heretoforeg bowling pins have ..b`een;constructed ofsoli'd'selecteditwood, or of ilaminations in which the/"beror grain of the wood runs vertically. The making "of a. bowling pin from a solid log requires. careful selection and slow seasoning of the log, which is expensive, and Various'built-up constructions heretofore have been proposed to overcome:,these difficulties and to reducezthecost of bowling pins. End" grain wood is more resistant to wearthan side or' radial grain wood, butJb'ec'ause ofthe greater tendency oi end grain wood to split under'impac't,- prior constructions exposing end grain to impact have not been successful.

In accordance with the present invention, a bowling pin is `constructed' of a plurality of horizontal laininations of aVV suitable wood glued together around a core with the grain or bers in the laminate running horizontally, the various laminations being angularly disposed to expose end grain in. thin laminations around the irnpaot band. of the pin. Inthe Wood core the grain runs lengthwise ofxthe pin, and the upper end of' the core may ber formed as the handle for the pin. Although thin laminations are essentialin the impact zone of the bowling pin, considerable latitude is permissible in the selection ofk the thickness of the laminations in thel other parts of the bowling pin. For eX- a-rnple, the thicker laminations may be made from one inch nominal thickness of wood which runs abou inch planed, and the thin laminations inthe: impact band maybe about onequarter upon'-v impact'- atlY its l end grain; areas, is'. greatly reduced, and at the same time theogreater re-v sistance to wear of end grain wood s utilized.

It isV known that the weakest glued joint in timber is obtained where the grain lines are dis posed ata ninety-degree angle, andthe strongest' glued joint is obtained where the grain lines are-substantially parallel. Where the wood layers are*l joined with the grain lines disposed atarr angleJother than a right ang1e',thestrengths-lciaimsl. (orfana-82) laranglezselected. This is disclosedand claimed' innmy' PatentNo'. 2,413,912, issued January 7, 1947, for Angular'Grlued Wood Joint. Inthe present invention, by employing thin laminations in the impact zone and arranging them substantially symmetricallywith the lgrain lines at an angle less than ninety degrees, I provide eX- posed end grain areas extending around the impact zone of the'bowling pin, and the thin laminations mutuallyv strengthen each other to prevent splitting under`v` impact. When a pin is struck by the' bowling ball in the impact band, the tendency of the end grain of a particular lamination to split is resisted by the adjacent transverse grain laminations which are strongly bonded thereto.

The thicker laminations bordering the impact zone also are disposed relative to the impact zone laminations and to each other so as to obtain a grain angle other than ninety degrees. Using laminations one quarter inch thick, a grain angle of about 45 is preferred although, by employing more thinner laminations in the impact Zone, a correspondingly smaller grain angle may be employed with a correspondingly improved bond between laminations and consequent improved resis tance to splitting. However, the cost of constructien rises with an increase'in thenumber of laminations. in any specic casefthe thinness of the laminations in the impact zone and. their number can' be balanced against the increased cost of making the bowling pin to obtain maximum life at minimum cost. The bottern of the bowling pin also is subject tov irnpact, and, if desired, the bottom band may also be composed of. a plurality of thin layers like the impact band.

The arrangement' ofgthe vlanfiinae with the grain iibers at a 45 angle in successive. layers is sim-` plined by formingeachlaminate as. an Octagon; Or, other angular' formations desired may: be easily made by cutting the laminas intheshape or' the corresponding regular polygon. After` gluing and bonding the laminations and. coretofgether, the resulting blank may be turned to sanded, and finished with a suitable VarL nish.

Although heretofore maple has been considered almost the only' wood suitable for bowling pins, pins constructed according toy the. present invention may be madeirom. otherkinds of tough, y ilurthermore,- the laminated con'. l struction enables the use of standardsaavnlseahard woods.

soned boards or veneers in the manufacture of the pins, thereby reducing the cost of material in the manufacture. It is also possible to govern the weight and balance of the pins by selecting and arranging the layers in accordance with the desired natural density of each layer, or by impregnating the pin with a suitable Varnish or resin, which also increases the hardness of the pin.

The invention will be described in greater detail in connection with the accompanying drawing showing preferred embodiments of the invention by way of illustration, and wherein:

Figure 1 is a side elevation of a bowling pin embodying the invention.

Figure 2 is a side elevation of an assembled blank for making the bowling pin shown in Figure 1,

Figure 3 shows in plan a set of laminae blanks, and

Figure 4 is a side elevation of a duck pin.

Referring to the drawing, the bowling pin, designated generally by the numeral I, is composed of a plurality of thin wood laminae 2a, 2b, 2c, etc-2n in the belly or impact zone, the grain or fibers in each lamina running horizontally, and the laminae being arranged so that each layer has its grain running at an angle of about 45 to the grain of the flanking layer. Any desired number of such layers or laminae may be employed depending on the thickness selected. For example, the standard bowling pin for use with a nine-inch ball is fifteen inches high, and the impact zone center is about 41A, inches from the base. The thin impact zone laminations in such a pin may occupy about 11/2 inches and preferably is made up of laminae about onefourth inch thick securely glued together. At least one full layer is positioned on either side of the mid-point of the impact zone, the layer 2c including the middle of the impact zone. On either side of the impact zone thicker glued laminations 3a, 3b, etc., Sn and lla, 4b, etc., lin may be employed, if desired. For example, as illusltrated the upper laminations 3a, etc. are composed of nominal one inch planed lumber, which is about 13/16` inch thick, four laminae glued together being used, and similar lower laminations 4a, etc. are used. If desired, the lowermost zone of the pin may be composed of one or more laminae of reduced thickness, such as, for example lg inch sawn veneer, the layers of veneer being glued together so that 'the grain of each layer is transverse to the next adjacent layer. This increases the impact strength at the end.

A bore B, which may be ltapered as shown, or cylindrical, extends through the laminations and receives a plug 9 in which the grain or bers run lengthwise. The upper end of the plug is enlarged at Il, and upon turning the bowling pin to shape this enlarged end provides the handle portion. This plug may be of one piece, but preferably is built up of three layers to provide increased resistance to splitting.

The mode of constructing the bowling pin will now be described. Referring to Figure 3, four laminae 2a, 2b, 2c and 2d are shown, these laminae being of octagonal shape and having each a central bore I4 therethrough. These laminae are assembled so that the bers in adjacent layers are disposed at an angle of about 45 to each other. Thus, layer 2b is interleafed between adjacent layers in which the bers run transverse at an angle of about 45 to the interleafed layer. v.Referring to Figure 2, it will be seen that six thin laminae, 2a, etc., are provided at the impact zone. The upper laminations 3a, 3b, etc. which do not receive as much impact are thicker, and are arranged with the fibers of adjacent layers running at an angle of 45 to each other. Also, the lower laminations 4a, 4b, etc., are thicker and are similarly arranged. The extreme end may be made up of a plurality of one sixteenth inch sawn layers 5, five such layers being shown, and the bottom thick layer 4b is suitably reduced in thickness to bring the middle impact layers 2a, etc. into the belly or impact Zone. The end layers 5 are preferably arranged with the bers in adjacent layers at about 45 to each other.

In fabricating a pin with a tapered core, the laminations, when freshly coated with glue, may be stacked one upon the other to the desired height, clamped together and held under pressure while the glue sets. Any suitable glue may be employed such as a cold-setting synthetic resinous glue which cures rapidly upon the application of heat. With this type of glue, the clamped assembly of laminations may be subjected to heat from any suitable source, although heat induced by the use of a high frequency field is preferred, because of the rapidity of its glue setting or curing action. The cylindrical bore of ythe cured stack is then reamed to form a tapered bore 8 and the tapered core or plug 9 is then wedged into the bore 8, clamped to hold its downwardly facing annular shoulder rmly against the upwardly facing side of the uppermost horizontal lamination, and glue bonded to the stack. The resulting blank, shown in Figure 2, may then be turned to appropriate shape, smoothed and nished or indurated with a suitable varnish.

As I have previously noted a cylindrical plug, having an enlarged upper end, may be used instead of the tapered plug B. With a cylindrical plug, the freshly glue-coated lamina-tions may be placed thereon, with the uppermost lamination abutting the annular shoulder presented by the enlarged upper end. When all laminations are on the plug, the entire assembly can be clamped, cured and thereafter machined and nished in the usual way.

In the modication shown in Figure 4, wherein like parts are indicated by like reference numerals, there is shown a duck pin embodying the invention. As the ball used for duck pins is 5% inches in diameter, ythe middle of the impact zone is 2% inches from the base, and thin 1aminae 2a, 2b, etc. are disposed to form the impact zone or belly of the pin. The upper laminations 3a, etc., and the lower laminations 4a, etc. are each made of planed wood of one inch nominal thickness. In `this pin, the wooden impact section is placed between the top and bottom sections an-d composed of a series of horizontal layers of wood arranged one over the other with each layer having its grain lines extending horizon-tally across the pin and with substantially all of the layers each having their grain lines extending at an angle to the horizontal grain lines of a flanking layer, as described in connection with Fig. 1.

I claim as my invention:

1. A bowling pin having an impact band at the largest diameter intermediate the ends of the pin comprising a plurality of thin laminae of wood adhesively bonded together with the fibers of each lamination running horizintally and disposed at a grain angle other than a right angle to the next adjacent lamination to provide exposed end grain around the impact band; and thicker laminations anking the impact band and arranged with the fibers of each said thicker lamination running horizontally and disposed at a grain angle other than a right angle to the next adjacent lamination; and a central plug extending through said laminas and being adhesively secured thereto, the fibers in the plug extending lengthwise of the pin, and the upper end of the plug extending from the laminations and providing the head and neck of the pin.

2. A bowling pin as specied in claim 1 wherein said grain angle in the impact band layers is about 45.

3. A bowling pin as specified in claim 1 wherein said central plug is tapered where it passes through said laminae.

4. A bowling pin as specified in claim 1 wherein the bottom of the pin has a band cornprising a plurality of thin laminae `of wood adhesively bonded together with the fibers of each lamination running horizontally and disposed at a grain angle other than a right angle to the next adjacent lamination to provide exposed end grain around said bottom band.

5. A bowling pin blank having an impact band intermediate the ends of the pin at a location corresponding to the largest diameter of the shaped pin, comprising a plurality of thin laminae of wood adhesively bonded together with the bers CORNELIUS D. DOSKER.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 940,341 Merklen Nov. 16, 1909 1,087,927 Deuther Feb` 24, 1914 1,513,570 Tischer Oct. 28, 1924 1,567,323 Jordan Dec. 29, 1925 1,722,557 Cherrette July 30, 1929 1,949,325 Paul Feb. 27, 1934 2,261,264 Luty Nov. 4, 1941 2,395,134 McKenzie Feb. 19, 1946 2,413,912 Dosker Jan. 7, 1947

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