Ball Bat With Eccentrically Thickened Walls

Abstract

This invention relates to ball bats and particularly to a bat with a tubular metal body wherein the wall thickness of the tube is eccentric to present a stronger ball striking area when the bat is properly oriented.

Description

BACKGROUND OF THE INVENTION

The invention relates to metal ball bats, and the method of making same is an improvement over my earlier U.S. Pat. No. 3,479,030 issued Nov. 18, 1969.

Bats made according to the above patent have proven quite successful for use in softball play and youth baseball or hardball play, however, problems were encountered in making an economical bat satisfactory for adult hardball play, The preferred method of making bats according to the above patent has been to use conventional extruded tubing which can be swaged as described in my earlier patent. For adult hardball play the wall of the tubing must be stronger than for softball to withstand the increased impact normally encountered. Merely increasing the wall thickness of the tubing, proved to be an unsatisfactory solution because the weight of the bat would be too great for acceptance by most adult players. To increase the hardness of the tube prior to swaging made the swaging step more difficult and cracking of the tubes occurred so that this alternative proved impractical. Another alternative would be to use materials suitable for softball play, swage, then heat treat to increase hardness, but this solution becomes too expensive and impractical for commercial acceptance.

SUMMARY OF THE INVENTION

According to the present invention ball bats are made substantially as described in my earlier patent, however, the starting metal tubes, rather than being conventional tubes of uniform wall thickness, are eccentric in wall thickness. The initial tubes are formed with a predetermined arcuate portion of greater wall thickness than the remaining arcuate portion. In this manner a tube may be formed, as by extruding, swaged and finished as described in my earlier patent and the finished bat may be used for adult hardball play by orienting the bat to present the thicker arcuate sector as the ball striking portion. Metal which can readily be swaged can thereby be used and the body of the bat kept within acceptable weight limits. An indicia cam be placed on the bat to assist a batter in properly orienting it, as is now done with wood bats where orientation of the wood grain is recommended.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view in elevation of a ball bat of the present invention;

FIG. 2 is a fragmentary elevation view, in section of an embodiment of the inventive ball bat;

FIG. 3 is a view in section of the handle end portion of the ball bat with vibration-dampening means inserted therein which includes a knob-like restraining end;

FIG. 4 is a view in section of another embodiment of the handle end including a generally tubular gripping sleeve about the handle end, with the sleeve being closed at the extremity end by a flange which serves as a knob-like restraining end;

FIGS. 5, 6 and 7 are end elevations taken along lines V--V, VI--VI and VII--VII respectively of FIG. 2 illustrating the wall thickness at various points along the ball bat, and wherein the relative wall thickness have been exaggerated to facilitate showing the present invention;

FIG. 8 is an end elevation of another embodiment illustrating a ball bat with a different cross-sectional configuration, again with the relative wall thicknesses being exaggerated to facilitate showing the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, the ball bat 10 comprises an elongated hollow metal body 11, vibration-dampening rubberous plugs 12, 13 which may be inserted respectively at the handle end and the free end portions of the body 11. A knob 11a may be affixed to the handle end portion. The metal body 11 generally comprises three sections or zones, A, B and C approximately equal in length. The body increases in external diameter from the section A to the portion C. The external diameter is generally constant along sections A and C, but of a greater diameter along C. The external diameter in section B tapers along its length from a diameter equal to section C down to a diameter equal to section A.

As can be seen in FIG. 2 and FIGS. 5 through 7, the wall thickness of any cross-sectional portion of the body 11 is eccentric. A predetermined contiguous arcuate wall sector along the length of the body is thickened relative to the remaining wall sector, so that the wall thickness in cross section is eccentric along the length of the bat in the preferred embodiment, whereby the thickened contiguous arcuate wall portion is utilizable as the ball striking portion when properly aligned by the batter. The eccentric wall portion may only extend along the free end portion which serves as the ball striking portion.

A cross-sectional angular wall sector of the reduced diameter handle portion has a wall thickness greater than the wall thickness of a substantially correspondingly cross-sectional angular sector of the free end portion of the preferred embodiment, as is clearly shown in FIGS. 5 and 7.

The handle end portion wall thickness need not necessarily exceed the wall thickness of the free end thin or thick arcuate wall sector in practicing the invention. This is particularly the case when the eccentric wall cross section extends along the full length of the bat.

The body 11 is preferably formed by the process of the invention which comprises forming a metallic generally tubular member, preferably by extrusion, having an eccentric cross-sectional wall thickness, with a constant external diameter, and being approximately equal in length to the desired final bat length. The external diameter of the tubular member is preferably of the same diameter as desired for portion C of the bat. The tubular member is then swaged to contour the portions A and B of the bat while thickening the walls thereof particularly in handle portion A. The swaged, resultant ball bat has a smooth, seamless surface which is ready for use.

The body 11 is preferably aluminum or an aluminum alloy of suitable hardness and temper as described in the U.S. Pat. No. 3,479,030, the teachings of which are incorporated herein. Aluminum alloys which can be used for example, include 6061T6 aluminum and 7005T53 aluminum available from the producers of aluminum. The wall thickness of the eccentric cross-sectional starting tube is for example about 0.08 inches at the thinnest wall sector, and about 0.11 inches at the thickest wall sector, with the wall thickness increasing approximately symmetrically from the thin portion to the thick portion. The handle portion in the preferred embodiment will also remain eccentric after the swaging, forming operation, but, of course, the wall thickness of the handle thick and thin wall arcuate portions will be correspondingly greater. The resultant ball bat will have a substantially uniform weight per unit length.

The wall thickness of the eccentric cross-sectional generally tubular body 11 can, of course, be varied. It is desirable that the deviation of the thick wall and thin wall portions from the average of the maximum and minimum thicknesses be greater than about 10 percent, and preferably about 10-15 percent. The deviation from the average wall thickness cannot be so great when a swaging operation is used in forming the final product that the product becomes distorted.

The contiguous arcuate sector which has a wall thickness exceeding the average wall thickness should extend for at least about 90.degree. to provide a sufficient strengthened striking portion, and it preferably extends for about 180.degree. or more. This thick wall portion is aligned by the batter to strike the ball, as is now done by a batter using a conventional wood bat having a grain. A suitable external marking can be provided on the ball bat of the present invention is assisting the batter to align the bat properly.

After the body 11 has been formed the vibration-damping rubberous plugs 12, 13 can be inserted into the handle and free end portions respectively. The plugs 12, 13 are formed to fit the interior of body 11. Such plugs and the use of an adhesive material to secure the plugs to the body are described in the aforementioned patent. The plug 13 shown in FIG. 2 at the free end portion has a bulbous extending end portion 14 and a generally cylindrical insertion end portion 15 which is fastened to the body 11, by a fastening pin 16, which extends through the insertion end portion 15, and is affixed to the wall of the body 11.

Another way of restraining the plug within the body 11 which can be used cooperatively or by itself, is to provide a raised surface 17 on the interior wall of body 11. This can be a circumferentially extending raised surface or a series of raised surfaces. The rubberous plug 13 can be grooved to accept the raised surface portion of the body 11.

A modified vibration-damping rubberous plug 12 is shown in FIG. 3. The plug is shaped to tightly fit within the bat handle, with a generally cylindrical portion 18 inserted into the bat handle. The end of the bat handle fits within a circumferential channel portion 19 of the plug, and a bulbous, knob-like extremity end portion 20 of the plug extends out beyond the end of the bat handle. The knob-like extremity acts as a restraint for the batter's hands. A fastening pin 21 extends through the bat handle and the cylindrical portion of the plug, with the pin being affixed to the bat handle.

A generally tubular gripping sleeve 22 can be tightly fitted over the handle end portion as seen in FIG. 4. The sleeve can be of any suitable material which facilitates gripping the ball bat, and an adhesive material can be used between the sleeve 22 and the bat to secure the sleeve thereto. The gripping sleeve 22 also preferably has a closed end portion 23 which includes a flange portion 24 of a diameter exceeding the tubular sleeve diameter to thereby serve as a knob-like restraining end.

An alternative ball bat embodiment is shown in FIG. 8, wherein the cross section of the wall of the body 11 is stepped, having a thin wall portion 25 and the thick wall portion 26. The generally tubular body 11 would be extruded in this fashion and then swaged to produce the ball bat of the present invention. The thick wall portion 26 preferably extends through at least about a 180.degree. arcuate sector of the tubular body.

Claims

I claim:

1. A ball bat comprising an elongated hollow metal body with a ball striking portion of predetermined outer diameter tapering through an intermediate portion of a predetermined outer diameter to a handle portion of reduced outer diameter, vibration dampening means disposed at least at one end of the hollow metal body, and a hand restraining knob means disposed at the handle end of the ball bat, the wall thickness of any cross section of said striking portion and said intermediate portion being similarly eccentric throughout their length, said eccentricity being of a predetermined contiguous arcuate wall sector of greater thickness than the remaining wall sector, and wherein said bat has a substantially uniform weight per unit length along a substantial portion of the bat length, and means provided on the exterior surface of the bat coinciding with the wall thickened arcuate sector of said striking portion to indicate to the user the proper orientation of the ball bat.

2. The ball bat as specified in claim 1, wherein the predetermined contiguous arcuate sector preferably extends through an angle of about 180.degree. or more.

3. The ball bat as specified in claim 1, wherein vibration-dampening means are disposed at both ends of the hollow metal body.

4. The ball bat as defined in claim 1, wherein the thickened contiguous arcuate sector has a maximum thickness which is approximately 10 to 15 percent greater than the average of the maximum and minimum wall thickness.

5. The ball bat as defined in claim 1, wherein the outer edge of the free end portion is provided with an internal bead, and including a rubberous plug disposed in the free end portion, the plug having a bead-receiving recess formed therein for restraining the plug when inserted in the free end portion.

6. The ball bat as defined in claim 1 including a rubberous plug disposed in the free end portion, and a restaining pin passing through the plug and the walls of the body.

7. The ball bat as specified in claim 1, including a generally tubular gripping sleeve on the handle portion.

8. The ball bat specified in claim 1, wherein said metal body substantially comprises aluminum.