Weight lifting drop bag

Abstract

Dropping a weight onto a weight lifting drop bag allows a weight lifter to drop a weight onto a floor with minimal damage to the floor, with minimal noise, and without any bouncing of the weight. The bag is a flexible enclosure filled with resilient pellets. The bag has a generally flat or slightly concave upper surface, a length of about two to eight feet, a width of about one and one-half to four feet, and a height of about two to twelve inches.

Claims

1. A weight lifting drop bag comprising a flexible enclosure filled with a plurality of resilient members wherein half of the plurality of resilient members have a density less than four pounds per cubic foot and half of the plurality of resilient members have a density greater than five pounds per cubic foot, the bag having a generally flat or slightly concave upper surface, a length of two to eight feet, a width of one and one-half to four feet, and a height of two to twelve inches.

2. The weight lifting drop bag of claim 1 wherein the plurality of resilient members in the bag are cubes that have a side length of one to three inches.

3. The weight lifting drop bag of claim 1 wherein the flexible enclosure contains an air vent.

4. The weight lifting drop bag of claim 1 wherein the plurality of resilient members are made of foam.

5. The weight lifting drop bag of claim 1 wherein the plurality of resilient members are cubes with a side length of two inches.

6. The weight lifting drop bag of claim 1 wherein the flexible enclosure has a mesh side wall.

7. A method of weight lifting comprising: (a) obtaining a weight lifting drop bag comprising a flexible enclosure filled with a plurality of resilient members wherein half of the plurality of resilient members have a density less than four pounds per cubic foot and half of the plurality of resilient members have a density greater than five pounds per cubic foot, the bag having a generally flat or slightly concave upper surface, a length of two to eight feet, a width of one and one-half to four feet, and a height of two to twelve inches; (b) setting the bag on a floor; (c) performing a lift using a weight, the weight consisting of a barbell, dumbbell, or other weight, in close proximity to the bag; and (d) dropping the weight onto the bag.

8. The method of claim 7 wherein the plurality of resilient members in the bag have a side length of one to three inches.

9. The method of claim 7 wherein the flexible enclosure of the bag contains an air vent.

10. The method of claim 7 wherein the plurality of resilient members in the bag are made of foam.

11. The method of claim 7 wherein the plurality of resilient members in the bag are cubes with a side length of two inches.

12. The method of claim 7 wherein the flexible enclosure of the bag has a mesh side wall.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a first embodiment of the weight lifting drop bag of this invention.

(2) FIG. 2 is a partial sectional view thereof.

(3) FIG. 3 is a perspective view of a second embodiment of the weight lifting drop bag of this invention.

(4) FIG. 4 is a partial sectional view thereof.

(5) FIG. 5 is a perspective view of a weight lifter performing a first part of an inclined dumbbell press on a bench with a weight lifting drop bag on each side of the bench.

(6) FIG. 6 is a perspective view of a weight lifter performing a second part of an inclined dumbbell press on a bench with a weight lifting drop bag on each side of the bench.

(7) FIG. 7 is a perspective view of a weight lifter completing an inclined dumbbell press on a bench by dropping the dumbbells onto a weight lifting drop bag on each side of the bench.

DETAILED DESCRIPTION OF THE INVENTION

1. The Invention in General

(8) This invention is best understood by reference to the drawings. Referring to FIGS. 1 and 2, a first embodiment of the weight lifting drop bag 100 of this invention comprises an enclosure 110 having a top 111, a side 112, and a bottom 113. The enclosure is filled with resilient members 120. Referring to FIGS. 3 and 4, a second embodiment of the weight lifting bag 200 also comprises an enclosure 210 filled with resilient members 220. The first and second embodiments differ primarily in size and shape. The first embodiment is especially suited for use with barbells while the second embodiment is especially suited for use with dumbbells.

2. The Enclosure

(9) The weight lifting drop bag has a size and shape to accommodate a dropped weight. The height (depth) of the bag is generally about two to twelve inches and is preferably about three to six inches. If the height decreases below about two inches, the cushioning decreases and the chances of the weight bouncing or bottoming out on the floor increases. If the height increases above about twelve inches, the weight and bulkiness make the bag an obstacle for others and cumbersome to move. The possibility also increases that the lifter may not have clearance over the bag to drop the weight.

(10) The preferred length and width of the bag depend on the dimensions of the weight that is to be accommodated. For example, bags having a length longer than their width (as shown in FIGS. 1 and 2) are preferred to accommodate a dropped barbell. Such shapes include rectangles and elongated ovals (when viewed from above) having a length of about five to eight feet and a width of about one and one-half to four feet. Bags having an approximately equal length and width (as shown in FIGS. 3 and 4) are preferred to accommodate a dropped dumbbell. Such shapes include squares and circles (when viewed from above) having both a length and width of about one and one-half to four feet. An especially preferred bag for dumbbells has a length of about 28 to 36 inches and a width of about 20 to 28 inches. As with height, excessive lengths and widths make the bag an obstacle for others and cumbersome to move.

(11) The upper surface of the bag is generally flat or slightly concave to accommodate a dropped weight and to reduce the possibility of the weight falling off the bag.

(12) The enclosure of the bag is made of a durable, flexible sheet material. Suitable materials include thermoplastics and fabrics. An especially preferred thermoplastic is a coated polyvinyl chloride (PVC) having a weight of about 20 ounces per square yard and a denier of about 1,000. This material has excellent tensile strength, excellent tear strength, and is easily cleaned. Fabrics such as denim and canvas have good strengths, but tend to be more difficult to clean. The optimal material for the enclosure is a matter of choice that depends on durability, cost, appearance, and ease of cleaning.

(13) The enclosure has at least one air vent 114 that allows air to enter and leave the interior of the enclosure, but prevents the resilient members from leaving. The presence of at least one air vent greatly reduces the possibility of damage to the enclosure's seams due to rapid air expansion when a weight is dropped. The enclosure preferably has side walls 115 made completely of mesh as shown in FIGS. 1 to 4. An especially preferred mesh is a dip coated interlocking grid weave scrim mesh having a weight of about 8 ounces per square yard and a denier of about 1,000.

3. The Resilient Members

(14) The bag is filled with a plurality of resilient members. The members have a nominal size of about one-half to three inches, preferably about two inches. Members smaller than about one-half inch are undesirable because they are prone to clumping and members larger than about three inches are undesirable because they provide less uniformity to the cushioning. The shape of members is a matter of choice and cubes, spheres, and random shapes are suitable. Members are preferably in the shape of cubes because of performance, durability, and cost.

(15) The resilient members are of varying densities. It was surprisingly discovered that resilient members of a single density are unable to provide the combination of cushioning and support required for optimal performance. In the preferred embodiment, resilient members of two different densities are used. About one-half of the members by volume are of relatively low density to provide the desired cushioning (to prevent bouncing) and about one-half of the members are of relatively high density to provide the desired support (to prevent the weight from bottoming out).

(16) The low density resilient members provide the necessary cushioning. The low density members are generally made of open cell foams having a density less than about 4 pounds per cubic foot. The low density members are preferably made of open cell polyurethane foams with a density of about 2 pounds per cubic foot with a minimum resiliency percentage of 20 percent.

(17) The high density resilient members provide the necessary support. The high density members are generally made of closed cell foams having a density greater than about 5 pounds per cubic foot. The high density members are preferably made of closed cell nitrile butadiene rubber (NBR) and polyvinyl chloride (PVC) foams with a density of about 7 pounds per cubic foot, a Shore 00 value of about 55, and a compression deflection value of about 6 pounds per square inch.

4. Uses and Advantages

(18) The use of the weight lifting drop bag can now be considered. Referring to FIGS. 5 to 7, a weight lifter 300 is shown performing an inclined press on a bench 400 with two dumbbells 500. Two weight lifting drop bags 600 are on the floor on either side of the bench. The weight lifting drop bags can be in close proximity before the lifting is begun or they can be moved into position after the lift is begun, either by the lifter or by a second person. After the lifter has completed lifting, he simply lets go of (releases) the dumbbells and allows them to drop onto the bags. The bags cushion the fall of the dumbbells without damage to the floor, with minimal noise, and without risk of the weight bouncing off the floor. A single bag is typically used when performing a lift with a barbell or a single dumbbell. Two bags are typically used when performing a lift with a pair of dumbbells.

(19) The weight lifting drop bag is relatively light in weight, is easily moved about a gym, and is easily stacked for storage when not in use. The bag is colored as desired for aesthetics and visibility.

(20) The weight lifting drop bag of this invention, and the method of using it, allow a weight lifter to drop a weight onto a floor with minimal damage to the floor, with minimal noise, and without any bouncing of the weight. The gym owner, the weight lifter, and others at the gym all benefit from use of the bag. The gym owner benefits by the reduced damage to the floor. The weight lifter benefits by being able to lift to failure without the need to set the weights down gently. And other people at the gym benefit from the reduced noise and the elimination of the danger of bouncing weights.

5. Example

(21) This example illustrates the effect of resilient member composition on the ability of a drop bag to absorb the impact of a dropped weight.

(22) A variety of resilient materials were obtained from different sources. The resilient materials were designated by the letters “A” through “E” and are described below:

(23) Foam A. An open cell polyurethane foam.

(24) Foam B. A closed cell nitrile butadiene rubber (NBR) and polyvinyl chloride (PVC) blend foam.

(25) Foam C. A closed cell polyethylene (PE) foam.

(26) Foam D. An expanded polystyrene (EPS) foam.

(27) Foam E. A recycled denim rebounded foam.

(28) The above resilient materials were tested in densities of about one to eight pounds per cubic foot and in various shapes, including sheet products, small pellets, cubes, and spheres. The above resilient materials were tested by themselves and in combination with other materials. The materials were placed inside a rectangular enclosure having dimensions of 32 by 24 by 4 inches and having two mesh side walls. A 100 pound weight was then dropped from a height of four feet and observed. Foam A and Foam B were found to be the preferred materials. The results of these preferred materials at varying percentages are shown in Table 1. The percentages are based on volume.

(29) TABLE-US-00001 TABLE 1 Effect of Resilient Member Composition Composition Observations 100% A, 2 lbs/ft.sup.3, 2 inch cubes Weight bottomed out 100% B, 7 lbs/ft.sup.3, 2 inch cubes Excessive bouncing 75% A, 25% B, as described above Weight sunk too deeply 25% A, 75% B, as described above Some bouncing 50% A, 50% B, as described above Optimal

(30) The results show that a mixture of 50% polyurethane foam with a density of two pounds per cubic foot in two inch cubes and 50% closed cell nitrile butadiene rubber and polyvinyl chloride blend foam with a density of seven pounds in two inch cubes provided the optimal combination of cushioning and bounce reduction.