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Publication numberUS3601398 A
Publication typeGrant
Publication dateAug 24, 1971
Filing dateApr 14, 1969
Priority dateApr 14, 1969
Publication numberUS 3601398 A, US 3601398A, US-A-3601398, US3601398 A, US3601398A
InventorsLouis R Brochman
Original AssigneeLouis R Brochman
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Ball-hitting practice device
US 3601398 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

llnited States Patent [72] Inventor Louis 1R. Brochman 310 W. Maple St., Stillwater, Minn. 55002 [21] Appl. No. 815,815 [22] Filed Apr. 14, 1969 [45] Patented Aug. 24, 1971 {54] BALL-HITTING PMCTHCE DEi/HCE 7 Claims, 8 Drawing Figs.

[52] 11.5. C1 273/26 12, 273/95 A, 273/200, 273/58 C, 2715/1316. 4, 273/D1G. 5 [51] Int. Cl A6393 69/40 [50] Field 01 Search 273/26 E, 29.1, 199, 200, 95 A, 58 C; 272/75 [56] Reterenm Cited UNITED STATES PATENTS 2,199,461 5/1940 Jones 273/95 A 2,606,025 8/1952 Homig 273/58 C 2,929,632 3/1960 Moffatt 273/200 3,212,777 10/1965 Spoczynski 272/75 3,408,070 10/1968 Gonzales et al 273/26 3,454,275 7/1969 Pontone 273/26 Primary Examiner Richard C. Pinkham Assistant Examiner-T. Brown Attorney- Robert C. Baker ABSTRACT: A device for practicing the art of hitting balls is disclosed. This device employs a single flexible nonfilamentary monolithic strand of organic thermoplastic material as the means for suspending or holding a plastic ball. The strand has a thickness of at least about one-sixteenth inch at a minimum. its thickness is no greater than about three-fourth inch or possibly 1 inch at a maximum. It is flexible and bends to permit varied movement for a ball hit in batting practice. The strand is mounted upon a stiff mounting bracket member through means including an organic plastic ear member; and the arrangement is such that the ear member and strand and ball are capable of swivel erratic and rotational movement as a unit without tangling or knotting of the strand when the ball is hit.

j BALL-HITTING PRACTICE riavrcrs Thieinvention relates to a device for practicing the art of hittii-ig'balls, particularly baseballs.

The device is especially useful as an economical safe-to-use training apparatus for youngsters in whom a baseball interest is just awakening. At such a stage, safe economical and reliable apparatus which provides fun is the only type apt to receive widespread use. It is especially vital at such a stage to minimize frustration during batting practice. The ball should be relatively easily hit by the young batter. He should be provided with varied elements of enjoyment as a result of hitting the ball. And, most important, the practice apparatus itself should not cause frustration by becoming temporarily inoperable as'a result of tangling orknotting of the. means forsuspending or holding the ball. Such frustrations for the;

youngster with an awakeninginterest in baseball can operate to discourage him not only with respect to further practice but also with respect to his own worth as abatter on a team composed of his peers.

A multitude of baseball-batting practice devices have heretofore been proposed. Illustrative such devices are set forth in thefollowing U.S. Pats: White No. l,862,044; Lake No. 2,017,720; Homing No. 2,606,025; Bales No. 2,976,040; l-laskett No. 3,006,647; and Lentine No. 3,366,383. One problem with devices in the prior art is that they are far too ambitious or complex to be made available on any economical basis for widespread home or private use by youngsters. Additionally, much prior art appears to teach devices wherein the ball is suspended by a flexible cable or cord or chain which is quite susceptible to becoming entangled or knotted in the event of an erratic hit; and this in turn introduces'an element of frustration for the youngster who is totally-inexperienced and needs to realize the appearance of success if not a truly successful batting practice session. In some other. prior art devices, entanglement or knotting of the ball suspending means is notpossible because the ball is held in rigid position at the end of a firmly fixed but resilient metal rod. However, where the ball is so fixed at the. end of a rigid wire or metal rod which prevents entanglement, the element of excitement and enjoyment in seeing a struck ball take on a variety of patterns 7 of movement after being hit is precluded. This in turn leads to fewer practice sessions. A still further objection to prior art devices is that their bulk or complexity militate against convenient carrying and movement of them by youngsters from place to place for joint practice sessions with others.

.This invention teaches a ball hitting practice device wherein the ball is suspended by a flexible strand which is entirely free of entanglementor kriotting regardless of how the ball is hit, but which at the same time'permits the ball to assume a variety its length. The cross-sectionalmass of the strandis at least about one-sixteenth inch in thickness at a minimum, and no greater thanabout three-fourths inchor' possible 11inch thick at a maximum. Mass' area in cross section should be in the range of about one-eightieth square inch up to about onetenth square inch. 'e

Ahollow ball of organic plastic material isattached to the freely depending endof the strand'against hittingdislodgement therefrom. Preferably a pattern of holes isprovided in the walls of this ball. i 1 7 An organic plastic ear member is united to the mounted end of the strand at the mounting bracket member. This ear member is equipped with an eyelet therethroughof a size sufficient to accommodate the spur shaft but smallerthan the size ofthe collar at theter'minus of the spur shaft of the mounting bracketi'lhe .ear member'is carried on the spur shaft with the spur shaft extending'throughthe eyeletthereof and with the collar serving as a guard against dislodgement 'of the ear member from the spur shaft. No ball 'bearingsare used. The arrangement is such that the ear member and strandand ball are capable of swivel erratic and rotational movement as a unit about thespur shaft without tangling or knotting of the strand when the ball is hit.

The invention will further be describedby reference to a drawing made a part hereof whereinz a FIG. 1 is a schematic cross-sectional view approximately bisecting all of the elements of the device; I

FIG. '2' is a schematic endplan view of theshowing in FIG. 1;

FIG. 3 is a fragmentary schematic plan' view of an ear member which supports the depending strand and attached ball;

'FIGS. 4, and 6 are cross-sectional views taken on line 4- 4, 5-5, and 6 -6 respectivelyin FIG. 1;

FIG. 7 is a fragmentary schematic plan view of an .ear member equipped with agrommet defining its eyelet; and

FIG. 8 is a schematic view illustrating themanner in which a test is. conducted to determine the Radius Bend Factor, as described herein,-for a strand of plastic material. 1

Referring to the'drawing, the device of the invention con* sists essentially of a stiff mounting bracket 10, a hollow ball 11, a single flexible nonfrlamentary monolithic strand of orof exciting and entertaining movements after it is struck. Significantly also, the arrangement of elements in the apparatus of this invention, and the nature of the elements themselves, is

such that a struck ball, after going through the motions caused by being hit, tends to return rapidly to a stationary position which permits ayoungsterto confidently and easily hit it again." In the preferred embodiment of the invention, as skill is built up, a youngster is further rewarded by a whistle-stop sound for an accurate true hit of the baseball, which further adds to the enjoyment of practice using the device of this invention; Still other advantages and benefits of the invention will be evident as this description proceeds.

The device of the invention has a base part which is called a stiff mounting bracket member. This member is characterized by havinga rodlike projection from its base mounting portion per so. A necklike spur shaft extends off the end of the rodlike projection; and a collar is provided at the terminusof the spur shaft. v

A singlelflexible nonfilalni entary monolithicstrand of organic thermoplastic material is a critical component of the device. One end of the strand is mounted for suspension from the mounting bracket; and'the other end is'freely depending.

The strand is essentially uniform in cross section throughout ing a rodlike projection I4 from the base mounting portion 15 thereof. At the base mounting portion 15 of the bracket 10 is located suitablemeans such as holes 16 for the'reception of screws (not shown) to'fix'the base mounting portion to a tree or post or other stationary object at any" suitable level for the youngster who is to use the practice device. If desired, the screw holes 16 may be omitted and a clamp may be employed to fix the base mounting portion 15 to a suitable stationary object; or the mounting bracket member may be held by hand by one youngster while anotherpractices hitting, preferably with a plastic bat.

Rodlike projection 14 of the mounting bracket 10 is formed of stiff material, if preferably integral or unitary or monolithic with the base mounting portionls, and may be of any suitable length, although a length up to about 2 or 3 feet is all that is mounting portion I5 itself need not be over about 2 or 3 inches in size or length; but the overall length of the member will usually be at least 18 inches up to about 30 inches or possibly 3 feet. Mounting bracket member 10 may consist of a length of wood, suitably evena rod or shaft of wood; but preferably it is formed entoto out of organic, plastic material of suitable character, with the central portion of the rodlike mounting projection 14 optionally being hollow, as illustrated,

without detracting from the total stiffness or rigidity for the mounting bracket member 10 itself. At a suitable wall thickness, such as walls at least about one-eighth inch thick,

and at a suitable overall cross-sectional size, such as an outer cross-sectional dimension of at least one-half inch (preferably at least I up to about 2 inches), hollow members even formed out of such plastics as polyethylene or polyvinyl chloride exhibit the necessary rigidity or stifi'ness for the mounting bracket. Of course, other plastics such as nylon (polyamide), polystyrene, polymethacrylates, etc., may be useful for the bracket member.

At the free end of the mounting bracket member is a necklike spur shaft 17 which preferably projects in approximate alignment off the end of the rodlike projection 14; and at the terminus of the spur shaft is a collar 18. The spur shaft 17 and the collar 18 (which latter is in the nature of a flanged head) are preferably molded integrally with the rodlike projection 14 of the mounting bracket member 10, particularly when the mounting bracket member is formed of organic plastic. Altemately, spur shaft 17 and collar 18 may be formed by embedding a screw or nail or thelike (suitably of metal or plastic such as nylon) into the end of the rodlike mounting projection 14.

The particular ball 11 chosen for the device may simulate a tennis ball or golf ball or the like, instead of a baseball. However, a hollow ball or organic plastic simulating the size of a baseball (e.g., preferably about 2.5 to 3 inches, or possibly 3.5 inches in diameter), is most acceptable to youngsters. Balls formed out of thermoplastics such as those of the vinyl type are especially useful (e.g., polymers of ethylene, vinyl chloride, and the like). Wall thicknesses for suitable hollow organic plastic balls may vary from around one-sixteenth inch up to about three-sixteenths inch, although even thicker walls may sometimes be suitable or desirable (e.g., one-fourth inch). The most preferred hollow plastic balls are those having a pattern of holes 19 through the walls and communicating with the interior of the ball, as illustrated. Diamond-shaped or circular-shaped holes or openings 19 (e.g., preferably having an area opening from about one-sixteenth square inch up to about one-fourth square inch) permit air movement in and out of the interior of the ball; and this, in turn, causes a whistling or whirring sound whenever the ball is hit so accurately as to whirl in a circle at the end of the strand 12 around spur shaft 17.

Plastic balls of the type contemplated are suitably formed by uniting two hemispherical sections by electronic welding or fusion, as is well known. The line of fusion 20 between two hemispherical sections is illustrated in FIGS. 1 and 6.

The critical nature of the strand 12 of organic thermoplastic material will now be discussed. This strand 12 is not composed of a multitude of fibers as'is characteristic for a cable. It is not a mere string or cord. It is composed of a single, flexible, nonfilamentary, monolithic, strand of organic thermoplastic material (such as, for example, a plastic of the vinyl type; polyethylene, polyvinyl chloride, etc.) Strand 12 is generally formed by extrusion and is quite flexible in that it can be forcibly bent by hand without applying any great pressure and returns to its strandlike or elongated character upon suspen-- sion after release of bending pressures. It can be knotted without fracturing. On the other hand, strand 12 has such a body or mass to it that it will not, under any circumstances involved in batting practice, behave as a string or a chain member and end up entangled or knotted. It will not behave as an elastic material causing ball 11 to bounce around in the manner characteristic of a ball on the end of a rubber band. Nevertheless, the plastic of the strand is not only flexible at the thicknesses or cross-sectional masses employed, but also has what might be called a stretchability or deformability which is such that the plastic can be stretched or deformed but recovers from such stretching or deformation only slowly, taking several seconds to do so, which distinguishes the plastic strand from rubbery elasticity (which it does not possess) where recovery after release of defonnation or stretch forces is on the orderof a second or even a fraction of a second.

Preferably, strand 12 is in the nature of a tube of thermoplastic material, as illustrated in the drawing; although a relatively solid or nonhollow strand (e.g., a solid cylinder or square or flattened strand) of plastic having the necessary properties may be suitable to employ. Tubular strands are especially efficient. They perform the necessary functions as described at a minimum of weight and mass.

The length of strand 12 is at least 12 inches and not over about 36 inches, with a length of 15 or 18 inches up to about 24 or possibly 30 inches preferred.

The cross-sectional character of strand 12 is essentially uniform throughout its length. In terms of thickness, its mass in cross section is at least about one-sixteenth inch at a minimum (and when so thin in one dimension it will be thicker in another so as to be straplike) and no greater than about three-fourths inch or possibly 1 inch at a maximum. This means that, where a hollow tubular strand is used as preferred, the mass taken in any cross-sectional direction through the tubing will be composed of two parts, or two walls. Mass area of plastic in cross section should fall within the range of about one-eightieth square inch up to about one-tenth square inch, but generally not over one-twentieth square inch.

As a means for testing the suitability of preferred-type strands for use in the function performed by strand 12 of this invention, a test has been devised. In this test, a strand of thermoplastic is placed in a vise 21 as schematically illustrated in FIG. 8, with the strand itself so mounted in the vise 21 as to project, at least for a moment or so of its length, in a horizontal direction outwardly from the vise 21. (Straplike or flattened strands are placed in the vise with their narrowest dimension parallel with the view shown in FIG. 8). An 18-inch length of the strand 12 is measured off from the bite of the vise, and the strand then is cut at the end of the l8-inch length. Then a /i-pound weight 22 is attached, suitably by clamps 23, to the end of the 18-inch length. Strand 12 then depends downwardly and assumes a shape somewhat comparable to that illustrated in FIG. 8. The radius of curvature for arc 24 is then measured from the center point of a circle coinciding with arc 24. The radius 25 from the center of that are to the surface of the strand l2 nearest that center is taken as the Radius Bend Factor for the strand 12. This Radius Bend Factor should be not less than about one-eighth inch and not in excess of about 6 inches for strands having the proper mass and characteristics of flexibility for use in the function described for strand 12 in the device of the invention. For the best strands, the Radius Bend Factor lies between about 1 and 5 inches.

Referring now to FIG. 1, the depending end 26 of strand 12 is securely attached to ball 11 so that the ball is secured against dislodgement from strand 12 during hitting practice. This may be accomplished by sealing the plastic strand 12 to the plastic ball 11. lllustratively, this is suitably done at the time of electronically sealing or fusing the two halves of ball 1 1 together, with the depending end 26 of strand 12 extending between meeting edges of the two halve sand slightly within the hollow interior of ball 11 to form a mass of plastic 27 within the interior. Fusion of the parts together provides a seal which unifies ball 11 to strand 12 to form more or less a monolithic whole. Where such a seal is undesired, or is impractical in a particular manufacturing operation, a suitable means whereby ball 1 1 may be securely attached to strand 12 is that of extending strand 12 through a first opening or hole 19in ball 11 and then out of ball 11 through another or second opening or hole 19. The end of strand 12 extending out of the ball 11 may then be knotted tightly and pushed back into the interior of ball 11 through the second hole 19. This is a quite satisfactory approach, particularly where a compressible tubular strand 12 is employed, inasmuch as the knot area itself may conveniently be compressed to push it back through the second hole 19 into the interior of the ball 11; and once that knot area is inside the ball, it expands somewhat and does not pass through the first hole through which the strand 12 was initially introduced into the ball. Of course, for this technique, at least two holes in the ball are formed to be of essentially the same cross-sectional size as the perimeter cross-sectional size of the hollow strand.

At the end of strand l2 herein identified as themounted end 28 (that is, the uppermost end) is located an organic plastic tab or lug or ear member 13. This ear member 13 is the part by which the strand 12 and ball 11 are hung. The ear 13 is united to the mountedend 28 of strand l2 and is preferably integral with strand 12. Preferably, ear member 13 consists of a flattened section of strand 12, such as illustrated in the drawing. An eyelet 30 extends through ear 13. The size of this eyelet is sufficient to accommodate or encompass spur shaft 17; but this eyelet is smaller than the collar 18 at the terminus of spur shaft 17. A slit 31 extending from the eyelet 30 partially into the mass of ear 13 may be provided to permit convenient assembly of the ear 13 over collar 18 to place eyelet '30 about spur shaft 17. Such a slit 31 is especially desirable where all parts of the device are formed of plastic, as is preferred.

It may also be observed that the preferred embodiment of the invention, composed of plastic in its entirely, consists essentially of two parts, each of which are essentially. monolithic in character. The first being the mounting bracket member and its accompanying spur shaft and collar; and the second being the depending or swivel elements which are the ball 1 l, the strand 12, and the ear member 13.

Of considerable significance is the fact that the ear member 13 in its mounting upon the spur shaft 17 is so arranged that the ear member is carried on that spur shaft and in turn carries the strand 12 and ball 11 for swivel erratic or rotational movement about spur shaft 17 without any danger of entanglement or knotting of strand 12 when the ball 11 is hit and therefore placed in action for a variety of movements. The plastic contact between the bearing surface of eyelet 30 and the spur shaft 17 is sufiiciently free of friction or free of undue friction to make the device entirely operable, even for swirling rotational movement of the ball 11 about the spur shaft 17 when ball 11 about the spur shaft l7 when ball 11 is squarely and directly hit. Such a direct hit, as aforenoted, is especially rewarding for the youngster inasmuch as the openings 19 in the hollow ball 11 permit an air movement which causes a whistling sound to accompany any speedy rotational movement of ball 1 1 around spur shaft 17.

If desired, eyelet 30 may be lined or defined by a grommet 32 of material different from the organic plastic of the ear member (e.g., a special plastic such as nylon where the ear member is a vinyl plastic; or even a metal or metallic grommet). A grommet-type lining for eyelet 30is useful in conjunction with a slit 31 as aforedescribed. The configuration of the rodlike projection 14 may be suitably contoured or enlarged at the very end of that rodlike projection adjacent the spur shaft 17 to provide a form of baffle plate or guide member to encourage or urge ball 11 into a swivel rotational movement about spur shaft 17 so as to enhance the possibility of a whistling sound even when ball 1 l is not squarely or directly hit.

As illustrated in the drawing, the almost insignificant weight a of the ball 11 and strand 12, plus the particular characteristics That which is claimed is: A

l. A device for practicing the art of hitting balls, consisting essentially of i. a stiff mounting bracket member characterized by having an elongated rod projecting from the base mounting portion thereof with a spur shaft of lesser diameter than said rod extending from the end thereof and a collar at the terminus of said spur shaft,

. a single flexible monolithic hollow strand of organic thermoplastic material, one end of which is identified as the mounted end and the other end of which is identified as the freely depending end, said strand being characterized (a) by being essentially uniform in cross section throughout its length, with the mass area of the material thereof in cross section being within the range of about one-eightieth square inch up to about one-tenth square inch, and (b) by exhibiting a Radius Bend Factor, as described herein, not less than one-eighth inch and not in excess of 6 inches, 7

iii. a hollow ball of organic plastic material, said ball being attached to the freely depending end of said strand against hitting dislodgement therefrom, and

iv. an organic plastic ear member united to the mounted end of said strand, said ear member being equipped with an eyelet therethrough of a size sufficient to accommodate said spur shaft but smaller than the size of said collar at the terminus of said spur shaft, said ear member being carried on said spur shaft with said spur shaft extending through the eyelet thereof and with said collar serving as a guard against dislodgementof said ear member from said spur shaft, whereby said ear member and said strand and ball are capable of swivel erratic and rotational movement as a unit about said spur shaft without tangling or knotting of said strand when said ball is hit. 2. The device of claim 1 wherein said strand is further characterized by the fact that the minimum thickness of its mass in cross section is at least one-sixteenth inch and by the fact that is exhibits a Radius Bend Factor, under test as herein described, between 1 inch and 5 inches.

3. The device of claim 1 wherein the mass forming said ear member comprises flattened thermoplastic material integrally united monolithically to the mounted end of said strand.

4. The device of claim 1 wherein said ear member is equipped with a slit extending from the eyelet thereof a fractional distance into the organic plastic of said ear member to permit expansion of the opening formed by said eyelet sufficiently to accommodate said collar during emplacement of said ear member over said collar and about said spur shaft.

5. The device of claim 1 wherein said eyelet of said ear member is equipped with a grommet formed of material different from the organic plastic of said ear member.

6. The device of claim 1 wherein the mounting bracket member, rod projecting therefrom, spur shaft and collar consist essentially of a monolithic organic plastic unit.

7. The device of claim 1 wherein the hollow ball has a pattern of holes through the walls thereof, said holes communicating with the hollow interior of the ball, whereby air movement in and out of the interior of said ball through said holes causes a whirring sound whenever said ball is hit so accurately as to whirl around said spur shaft.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. $601,398 Dated ug- 24, 1971 l Louis R. Brochman It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 60, "whistle-stop" should read whistletype Column 2, line 3, "possible" should read possibly Column 4, line 53, "halve sand" should read halves and Column 5, line 34, cancel "about the spur shaft 17 whenv ball 11''. Column 6, line 37, "is" should read it Signed and sealed this 12th day of September 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents *oRM PC4050 (10-69) USCOMM-DC 00876-P0B U.S. GOVERNING? PRINTING OFFICE Ill, 0-368-33.

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Referenced by
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U.S. Classification473/424, 473/145, 273/DIG.500, 273/DIG.400
International ClassificationA63B69/00
Cooperative ClassificationA63B69/0079, Y10S273/04, Y10S273/05
European ClassificationA63B69/00T2