US3827689A

US3827689A - Gymnastic horizontal bar

Info

Publication number: US3827689A
Application number: US00364017A
Authority: US
Inventors: G Hyde
Original assignee: Permali Inc
Current assignee: Permali Inc
Priority date: 1973-05-25
Filing date: 1973-05-25
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06
Also published as: CA993465A

Abstract

A gymnastic horizontal bar is formed from thin wooden strips extending lengthwise of the bar side by side in parallel vertical planes, with laterally spaced reinforcing tapes sandwiched between some of the strips at both sides of the longitudinal axis of the bar. The tapes and wooden strips are laminated together to form a unitary bar of increased resistance to lateral impacts. The areas of the pair of wooden strips engaging the opposite sides of each tape are compressed by the tape so that the pair of strips engage each other above and below the tape, whereby the tapes are concealed and the bar has a continuous wooden surface.

Description

11] 3,827,689 1451 Aug 6,1974

[ GYMNASTIC HORIZONTAL BAR [75] Inventor: George W. Hyde, Mt. Pleasant, Pa.

[73] Assignee: Permali Incorporated, Mount Pleasant, Pa.

22 Filed: May 25,1973 21 Appl. No.: 364,017

[52] US. Cl 272/63, 52/309, 52/730 [51] Int. Cl A63b 3/00 [58] Field of Search 272/62, 63, 67 R, 67 D, 272/72 R, 167 R, 59 C, 60 R; 52/309, 642,

730; 211/123, 124; 273/67 R, 67 D, 72 R,

167 R, 67 DA, 73 F, 73 K, 82 R, DIG. 7

[56] References Cited UNITED STATES PATENTS 2,596,894 5/1952 Frisch 273/67 R X 3,167,882 2/1965 Abbott 52/730 X FOREIGN PATENTS OR APPLICATIONS 305,412 271929 7 Great Britain 273/73 K 1,163,208 2/1964 Germany 272/63 231,199 3/1944 Switzerland... 52/730 1,816,112 10/1969 Germany 273/73 F Primary Examiner-Richard C. Pinkham Assistant Examiner-R. T. Stouffer Attorney, Agent, or Firm-Brown, Murray, Flick & Peckham [5 7] ABSTRACT A gymnastic horizontal bar is formed from thin wooden strips extending lengthwise of the bar side by side in parallel vertical planes, with laterally spaced reinforcing tapes sandwiched between some of the strips at both sides of the longitudinal axis of the bar. The tapes and wooden strips are laminated together to form a unitary bar of increased resistance to lateral impacts. The areas of the pair of wooden strips engaging the opposite sides of each tape are compressed by the tape so that the pair of strips engage each other above and below the tape, whereby the tapes are concealed and the bar has a continuous wooden surface.

5 Claims, 3 Drawing Figures GYMNASTIC HORIZONTAL BAR Horizontal bars are used in gymnastic equipment in which two laterally spaced bars are at the same level, or in gymnastic equipment where the bars are spaced even farther apart and are at different levels. Such bars originally were made of solid wood, usually hickory, which was profiled to provide a cross sectional shape that would be comfortable to the hands that gripped the bars. As gymnastic performances became more complicated and strenuous, the stresses to which the bars were subjected became higher so that solid wood bars no longer were satisfactory from a strength standpoint. To increase their strength, the industry resorted to laminated bars composed of densified thin wooden strips or veneers glued face to face. Such bars are used with the laminations in vertical planes. Their cross sectional contour generally is egg-shaped with the greatest width of the bar above a point midway between the highest and lowest areas of the bar.

Such laminated bars were satisfactory for awhile, but as the gymnastic exercises continued to become more vigorous and strenuous the bars would break occasionally under the sudden load of gymnasts striking them at high speed. To prevent injury to the gymnast when a bar broke, the practice was adopted of incorporating a steel reinforcing rod in the laminated bar substantially at its center of gravity. This rod, being at the neutral axis of the bar, did not increase the breaking strength of the bar but it did prevent the broken ends from separating. The gymnast thus was allowed to dismount without injury. Nevertheless, even though there is no injury when a bar breaks, such an occurrence disrupts the performance and has a demoralizing effect on the gymnasts mental condition. The cross section of the bar cannot be increased to strengthen it, because the bar must fit the hand of the gymnast and also because in order to be used in competition the dimensions of the bar must conform to those specified by the International Gymnastic Federation.

It is among the objects of this invention to provide a gymnastic horizontal bar which will not break during the most strenuous of present day gymnastic performances, which retains the size and shape of the customary horizontal bars, which retains the required degree of flexibility, and which feels right to the gymnast.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which FIG. 1 is a perspective view of the bar;

FIG. 2 is an enlarged end view of the bar; and

FIG. 3 is a longitudinal section taken on the line III- III of FIG. 2.

Referring to the drawings, a horizontal bar 1 of the usual size and shape used in athletic equipment employed by gymnasts is more or less oval or egg-shape in cross section as shown in FIG. 2. The ,bar likewise is formed from a plurality of thin wooden strips 2 that extend lengthwise of it side by side in parallel vertical planes. The widest strips in the vertical direction are thus at the center of the bar, with the rest of the strips becoming narrower as they approach the opposite sides of the bar. The bar is a laminated wooden bar, but it is a feature of this invention that it is reinforced in a horizontal direction. In other words, the resistance of the bar to breaking due to lateral impacts against it has been increased over conventional laminated bars.

According to this invention, this strengthening of the bar is accomplished by disposing or sandwiching between at least some of the adjoining wooden strips high strength reinforcing tapes 3 that extend lengthwise of the strips. These tapes are located at opposite sides of the longitudinal axis of the bar and may consist of one or more of such tapes at each side. A total of eight tapes are shown in the drawings, but there could be two or more. The fewer there are, the less the strengthening of the bar. On the other hand, if so many tapes are used that some are close to the central vertical plane of the bar, those centrally located tapes will not have much effect because they are too close to the neutral axis of the bar. For best results, combined with economy, the innermost tapes should be spaced a considerable distance from the central vertical plane of the bar; for example, at least about a third of the distance between that plane and either side of the bar.

The tapes should extend vertically as far as possible without being exposed at the surface of the bar. In other words, the upper and lower edges of the tape should be spaced a short distance inwardly from the adjacent edges of the adjoining wooden strips. The purpose of this is to retain the wooden surface of the bar, with no exposed edges of tape that might scratch the gymnasts hands.

The wooden strips and the tapes are laminated together with the help of a suitable adhesive 4; for example, a phenolic glue. The tapes may be only about 0.010 inch thick, which is so thin that when the strips and tapes are laminated the pressure used in the process can press the tapes into the adjoining wooden strips so that there will be no gaps between those strips in the marginal areas beyond the upper and lower edges of the tapes. Thus, the marginal areas of all of the wooden strips engage one another.

Each of the tapes preferably is formed from fiberreinforced synthetic resin, with substantially all of the fibers extending continuously from end to end of the tapes. The fibers may be glass filaments. Graphite filaments also are highly satisfactory, but more expensive. The making of continuous filament tapes of this nature is a well-known art and such tapes can be purchased on the open market.

Without the reinforcing tapes, the bar is weakest in a horizontal direction; that is, in a direction perpendicular to the laminations. This is because the width of the bar is less than its vertical dimension and its strength varies inversely as the square of the dimension being considered. However, as a result of this invention, the strength of the bar in a horizontal direction is materially increased. This increase is made in order to resist horizontal stresses occuring when a gymnast strikes the side of the bar with his hands or body. When such an impact occurs, the reinforcing tapes at the side of the bar opposite to the side that receives the impact are put under tension and become load-bearing to help the wooden laminations resist breaking.

Although it is not considered necessary, for peace of mind the bar may be provided with a central steel rod for the same purpose that it has been used heretofore.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. A gymnastic horizontal bar that is substantially oval in cross section with its maximum width less than its depth, the bar comprising wooden strips extending lengthwise of the bar side-by-side in parallel vertical planes, laterally spaced reinforcing tapes extending lengthwise of said strips at opposite sides of the longitudinal axis of the bar, each tape being sandwiched between an adjoining pair of said strips in engagement therewith and extending above and below said axis, the upper and lower edges of the tapes being spaced inwardly from the adjacent edges of said wooden strips, and adhesive material laminating said tapes and wooden strips together to form a unitary bar of increased resistance to lateral impacts, the areas of the pair of wooden strips engaging the opposite sides of each tape being compressed by the tape so that said pair of strips engage each other above and below the tape, whereby the tapes are concealed and the bar has a continuous wooden surface, the length and crosssectional dimensions of said bar being sufficient for said bar to support the weight of an ordinary human being at such time as said human being is performing gymnastic exercises on said bar while substantially the entire length of said bar is spaced upwardly from a supporting surface.

2. A gymnastic horizontal bar according to claim 1, in which there is a plurality of said tapes at each side of said bar axis, the innermost tape at each side of the central vertical plane of the bar being spaced from that plane at least about a third of the distance between said plane and the adjacent side of the bar.

3. A gymnastic horizontal bar according to claim 1, in which each of said tapes is formed from synthetic resin reinforced with filaments, substantially all of which extend continuously from end to end of the tape.

4. A gymnastic horizontal bar according to claim 1, in which each of said tapes is about 0.010 inch thick.

5. A gymnastic horizontal bar according to claim 1, in which there is a plurality of said tapes at each side of said bar axis, each of said tapes being about 0.010 inch thick and formed from synthetic resin reinforced with glass filaments, substantially all of which extend continuously from end to end of the tape.

Claims

1. A gymnastic horizontal bar that is substantially oval in cross section with its maximum width less than its depth, the bar comprising wooden strips extending lengthwise of the bar side-byside in parallel vertical planes, laterally spaced reinforcing tapes extending lengthwise of said strips at opposite sides of the longitudinal axis of the bar, each tape being sandwiched between an adjoining pair of said strips in engagement therewith and extending above and below said axis, the upper and lower edges of the tapes being spaced inwardly from the adjacent edges of said wooden strips, and adhesive material laminating said tapes and wooden strips together to form a unitary bar of increased resistance to lateral impacts, the areas of the pair of wooden strips engaging the opposite sides of each tape being compressed by the tape so that said pair of strips engage each other above and below the tape, whereby the tapes are concealed and the bar has a continuous wooden surface, the length and cross-sectional dimensions of said bar being sufficient for said bar to support the weight of an ordinary human being at such time as said human being is performing gymnastic exercises on said bar while substantially the entire length of said bar is spaced upwardly from a supporting surface.