This invention relates to height adjustable nets for use in games such as volleyball.
Volleyball regulations have specific requirements for the volleyball court and equipment. A volleyball net is required to be 3 feet (1 meter) wide and at least 32 feet (9.5 meters) in length. The upper edge margin of the net comprises an elongate sleeve through which a net-supporting cable extends. Typically, the net is attached to upright standards via the net-supporting cable. Preferably, the standards are 3 feet (1 meter) outside a volleyball court""s sidelines. The width of the court (i.e., the distance between the sidelines) is 9 meters. The height of the net is measured at the center of the net and is required to be 7 feet, 11⅝ inches (2.43 meters) for men and 7 feet, 4xe2x85x9 inches (2.24 meters) for women. The net height measured at the ends of the net is not permitted to exceed the center height by more than xc2xe inch (2 millimeters). In other words, the net cannot sag by more than xc2xe inch (2 at its center. To prevent excessive sag, the net-supporting cable must be maintained at a sufficient tension.
Because the net""s height requirements are different for men""s volleyball and women""s volleyball and because men""s and women""s volleyball are played on the same courts but at different times, it is often necessary to change the net""s height. In prior art net/standard systems, the net height is varied by first relieving the tension on the net-supporting cable and then lowering the standard. After the net is positioned at its new height, the net-supporting cable is re-tensioned to prevent excessive sag. Changing the net height in this manner is time consuming. Also, it is difficult when changing the height to obtain the precise required height. This is because the net""s height increases slightly upon tensioning of the net-supporting cable. Unless the increase caused by the tensioning is taken into account before the cable is tensioned, it will be necessary to again relieve the tension of the cable, lower the net to the proper height, and then re-tension the cable.
Among the features and advantages of the present invention may be noted the provision of an improved method of changing the height of a volleyball net; the provision of such a method in which the net height may be adjusted quickly and easily; the provision of such a method in which the net height may be varied without relieving tension on the net-supporting cable; and the provision of an improved height-adjustable net and standard system.
Generally, a method of the present invention for adjusting the height of a volleyball net comprises securing first and second net standards to a support surface, such as a floor, in a manner so that the net standards extend up from the support surface in a generally upright position. Each net standard comprises a lower post section and an upper post section slidably connected to the lower post section for telescoping movement of the upper post section relative to the lower post section along a post axis between a raised position and a lowered position. A net and cable assembly is provided. The net and cable assembly comprises a net and a net-supporting cable. The net has an upper edge margin and a cable-receiving sleeve at its upper edge margin. The upper edge margin has first and second ends and a mid-point midway between the first and second ends. The net-supporting cable extends through the cable-receiving sleeve of the net. The method further comprises operatively connecting the net-supporting cable to the upper post sections of the first and second net standards in a manner so that the net is between the first and second net standards and extends downward from the net-supporting cable, tensioning the net-supporting cable to a net-supporting tension which is sufficiently great that the elevation of the first and second ends of the net""s upper edge margin does not exceed the elevation of the mid-point of the net""s upper edge margin by more than approximately xc2xexe2x80x3 (2 cm) when the first and second ends of the net""s upper edge margin are at approximately the same elevation, and moving the upper post sections of the first and second net standards between their raised and lowered positions without reducing the tension of the cable below the net-supporting tension.
Another aspect of the present invention is a height-adjustable net and standard system for use in ball games such as volleyball. The net and standard system comprises first and second net standards, a net, a net-supporting cable, and at least one tension adjusting mechanism. The net standards are adapted for being secured to a support surface, such as a floor, in a generally upright orientation so that the first and second net standards are horizontally spaced from one another. The net has an upper edge margin, a lower edge margin, and side margins. The net has a cable-receiving sleeve at its upper edge margin. The net is adapted to be supported by and extend between the first and second net standards. The net-supporting cable is adapted for extending through the cable-receiving sleeve of the net and for supporting the net between the net standards. Each of the first and second net standards comprises a lower post section, an upper post section and a drive mechanism. The upper post section is slidably connected to the lower post section for telescoping movement of the upper post section relative to the lower post section along a post axis between a raised position and a lowered position. The drive mechanism is operatively connected to the upper and lower post sections. The drive mechanism is operable in a manner to axially move the upper post section relative to the lower post section between its raised and lowered positions. The tension adjusting mechanism is attached to the upper post section of the first net standard and is adapted to tension the net-supporting cable in a taut configuration between the first and second net standards. The drive mechanism is adapted to move the corresponding upper post section between its raised and lowered positions even when the cable is tensioned by the tension adjusting mechanism.
Other objects and features will be in part apparent and in part pointed out hereinafter.
USPTO Backgrounds
USPTO Backgrounds