Abstract:
A liquid-fillable heavy training bag includes a cylindrical flexible outer shell having top and bottom walls to form a generally closed cylindrical inner surface. Suitable support is provided for suspending the cylindrical outer shell from an upper support member, such as a ceiling. A generally cylindrical liquid-impermeable flexible liner is provided within the outer shell for receiving and containing a liquid medium such as water. The liner is configured and dimensioned to generally conform to the shape of the inner surface of the outer shell when the liner is fully expanded, such as when filled with water. An intermediate layer is provided made of compressible material and arranged between and contacting the outer shell and the liner when the liner is filled with liquid. The intermediate layer forms a cushion for absorbing external impacts to the outer shell and absorbs and attenuates shock waves imparted to the liquid medium within the liner to protect the liner and better simulate the feel of a conventional, non-liquid filled heavy bag.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention generally relates to heavy training bags and, more specifically, to a liquid-fillable heavy training bag.  
         [0003]     2. Description of the Prior Art  
         [0004]     Heavy training bags, sometimes referred to as simply heavy bags or training bags, have been used for many years. These types of bags, also commonly called punching bags, are generally sturdy bags designed to be repeatedly punched or kicked for use for exercise or physical training. Such heavy training bags are typically used to improve one or more of the following: physical strength, cardiac fitness, punching techniques or martial arts skills.  
         [0005]     While some punching bags may be designed to look at least abstractly realistic as an opponent and assume the human or partial human form, such bags are typically in the form of an elongate cylindrical outer shell and suspended from a chain or other attachment means to secure the heavy bag in a vertical or upright position suspended from an upper support. Such bags can be, for example, 32″-45″ long, approximately 14″ wide and typically weigh 70-100 pounds. Many of these bags are stuffed with a specially blended filler material to absorb punches or kicks without excessive lateral movements as it is intended that these bags provide resilient shock absorbency to somewhat stimulate the shock absorbing properties of an opponent. Depending on the intended feel of the bag, the outer cover may be stuffed with different filler materials. In some cases, dual bag shock absorption systems are provided by including a foam layer or lining in addition to the filler material.  
         [0006]     A disadvantage of conventional heavy or training bags is that they are heavy when filled with filler material and are bulky. Most such bags are in their fully expanded conditions, that they assume during use, so that a purchaser can simply remove the bag from the box or other packaging, hang up the bag and start using it. However, while this is convenient for the end user, these bags are heavy and expensive to ship, display, store by retailers and all of these issues increase the cost of the item. One approach that has been proposed to eliminate at least some of these problems is to provide a heavy or training bag that is initially in a collapsed form that can be expanded by the ultimate purchaser or user prior to use. One common design is to provide a bag that has all of the common dimensions of conventional bags but has an inside liner or bladder that can be filled with water or other fluid. The water or liquid is sufficiently heavy so that when the bag is filled up it has the weight and shock absorbent properties that simulate those of conventional fiber-filled bags. These bags have the advantage that they can be shipped and stored in a collapsed form and can also be emptied of the water or fluid when the bag is not to be used for an extended period of time to facilitate storage of the bag. While many liquid filled bags have been proposed, many suffer a number of disadvantages. One disadvantage is that the punches or kicks applied to the bag provide substantial shock waves within the water or liquid and these, especially over time, can have the effect of weakening and ultimately breaking the liner or bladder. This is especially true when the liner or bladder is held in place within a confined space and there is no real area for expansion as a result of punching or kicking actions on the bag. The water or liquid, in such cases, will tend to be displaced in the path of least resistance. This, frequently, is the position in which a closure is provided through which water or liquid can be introduced. If such closure is damaged the bag becomes essentially useless because punches or kicks to the bag will simply cause the water or liquid to be expelled through the damaged closure. Therefore, while water or liquid filled bags have solved some problems they have raised others.  
       SUMMARY OF THE INVENTION  
       [0007]     Accordingly, it is an object of the invention to provide a heavy training bag that does not have the disadvantages of prior art of known heavy training bags.  
         [0008]     It is another object of the invention to provide a heavy training bag which is simple in construction and economical to manufacture.  
         [0009]     It is still another object of the invention to provide heavy training bag of the type on the discussion that can be shipped and stored in a fully collapsed state and expanded to a suitable form once filled with water or another fluid.  
         [0010]     It is yet another object of the invention to provide a heavy training bag as in the previous objects that protects the internal liner filled with water or fluid to accommodate the shocks transmitted through the water or fluid without damaging the liner over extended use.  
         [0011]     It is a further object of the invention to provide a heavy training bag as in the previous objects that provides the look and feel of a conventional heavy training bag.  
         [0012]     It is still a further object of the present invention to provide a heavy training bag as in the last object that can be shipped disassembled but can be conveniently and quickly assembled by an end user.  
         [0013]     It is yet a further object of the invention to provide a heavy training bag of the type under discussion that significantly reduces the cost of manufacturing conventional heavy training bags without compromising their characteristics or properties to the end user. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     Various further objects, features and advantages of present invention will be more fully appreciated and the invention will be better understood in light of the accompanying figures, in which:  
         [0015]      FIG. 1  is a perspective view of a heavy training bag in accordance with the present invention, shown suspended from a support surface and ready for use.  
         [0016]      FIG. 2  is a cross-sectional view of the heavy training bag shown in  FIG. 1  taken along a longitudinal section line  2 - 2 .  
         [0017]      FIG. 3  is a cross-sectional view of the bag shown in  FIG. 2 , taken along a transverse section along line  3 - 3 .  
         [0018]      FIG. 4  is a elevational view of a section of the interior surface of the heavy training bag, as viewed along the region  4 - 4  in  FIG. 3 .  
         [0019]      FIG. 5  is a perspective view of a section of the heavy training bag shown in  FIG. 4 .  
     
    
     DESCRIPTION OF PREFERRED EMBODIMENT  
       [0020]     Referring now specifically to the figures, in which identical or similar parts are designated by the same reference numerals throughout, and first referring to  FIG. 1 , a liquid-fillable heavy training bag in accordance with the present invention is generally designated by the reference numeral  10 .  
         [0021]     As with conventional or heavy training bags, the bag  10  includes an outer tubular shell or cover  12  which has a bottom wall at a lower end  12   a  and a top wall at an upper end  12   b . The outer tubular cover  12  is a generally cylindrical flexible outer shell that may be made from any one of a number of materials typically used for conventional bags. This includes canvas, vinyl, leather or any other strong flexible sheet material that can withstand repeated punches or kicks to the outer surface of the bag. The bag  10  may be made in virtually any size commonly used for conventional bags. The cover defines a generally closed cylindrical inner surface  12   c.    
         [0022]     Although the outer tubular cover or shell is shown as a right circular cylinder giving circular upper and lower walls, it is possible to provide the cover or shell  12  with different configurations, including square, triangular, etc. cross-sections.  
         [0023]     As with conventional heavy or training bags, a number of support straps  14 , typically 3 or 4, are secured to the upper end  12   b  by means of any attachment means, such as stitching  16  although other devices may be used to attach the straps such as rivets or other fasteners. Also, as with conventional heavy bags, the support straps  14  may be formed as strips folder over to create an outer portion  14   a  and an inner portion  14   b , both portions of which are secured to the outer tubular cover  12  such as by stitching. This creates a through opening  18  in each of the support straps  14  for accommodating a portion of a loop, link or ring  20 . While a triangular link is shown in  FIG. 1 , it will be evident that any shaped link may be used and such links are preferably made from a rod the ends of which are welded to each other to form a closed link, ring or loop to prevent the link from opening after repeated stresses applied during use of the bag.  
         [0024]     In use, a ring  22  is secured to a support surface  24  in any conventional manner and chains  26  extending between each of the links  20  and ring  22  support the bag  10 . The bag is balanced when the support straps  14  are substantially uniformly spaced about the bag as shown. Any suitable means for securing the chains  26  to a support surface may be used. The links of the chains  26  are also preferably welded so that they don&#39;t open as a result of significant stresses applied when the bag is punched or kicked.  
         [0025]     At the upper end  12   b  of the bag a rim  28  is shown which is a curved or circular border or edge that extends about the periphery of the bag to create a recess  30  within which a top cover, wall or flap  32  is arranged that can be selectively and partially attached to the rim  28  or opened to provide access to the interior of the bag by means of a zipper  34 .  
         [0026]     Referring also to  FIG. 2 , a bottom wall  36  is provided that may be made of the same material as the outer tubular cover  12  and may be secured to the latter by any conventional means, such as stitching  38 . As will be appreciated, the bottom wall  36  is, therefore, permanently attached to the outer tubular cover  12 , while the top cover or flap  32  is selectively attached to the outer tubular cover and may close the upper end in the region of the recess  30  to block access to the interior of the bag or to open the upper end  12   b  to provide such access.  
         [0027]     Inserted into the outer tubular cover  12  is a lower foam disc  40  which has a diameter substantially corresponding to the internal diameter of the outer tubular cover  12 . In assembling the bag, the lower foam disc  40  is initially inserted to the position shown in  FIG. 2 . Subsequently, an outer foam layer  42  is inserted that can either be a closed annular layer or may be a rectangular sheet that is folded upon itself to bring the opposing edges into abutment against each other when the outer layer  42  is inserted within the outer tubular cover  12 .  
         [0028]     In the presently preferred embodiment, secured to the inner surface of the outer foam layer  42  is an inner foam layers formed of alternating inner foam layers  44  and vertical hollow tubes  46 . While not essential, the inner foam layers  44  and vertical hollow tubes  46  are preferably secured to the interior surface of the outer foam layer  42  by means of any suitable bonding agent  47 , such as adhesive, mechanical bonding or the like to facilitate assembly. By attaching the inner foam layers  44  and vertical hollow tubes  46  in an alternating fashion and in a uniform manner about the outer foam layer  42 , as shown in  FIG. 3 , the user need not handle a large number of inner foam layers and vertical hollow tubes  42 ,  44  respectively and try to manipulate those and secure them in place as shown while assembling the unit. Because the outer foam layer  42  as well as the inner foam layers  44  and vertical hollow tubes  46  are all made of a compressible foam material these layers and tubes can be significantly compressed for purposes of shipment and storage.  
         [0029]     The specific dimensions of the layers  44  and tubes  46  are not critical but the outer diameters of the tubes  46  should be approximately equal to the radial thickness of layers  44  are in the range of 3-5 times the diameters of the tubes  46 .  
         [0030]     Once the inner foam layers  44  and vertical hollow tubes  46  are in place, as shown in  FIG. 2 , resting on the lower foam disc  40  as shown, a liner or bladder  48  is inserted through the upper end  12   b  with the top cover or flap  32  un-zippered and opened. The diameter of the liner  48 , in its expanded position, substantially corresponds to the inner diameter of the inner foam layers  44  and vertical hollow tubes  46  so that once the liner is filled with water it abuts against and presses on the inner layers and tubes  44 ,  46 , respectively, to urge the outer foam layer  42  and outer tubular cover  12  radially outwardly to maintain the bag  10  in its desired overall configuration or shape shown on  FIG. 1 . The outer layers  42  and the foam discs  40 ,  56  together form an outer layer of an intermediate layer of compressible material, while the inner foam layers  44  and tubes  46  form an inner layer of compressible material of the intermediate layer.  
         [0031]     The liner or bladder  48  includes a bottom wall  48   a , a top wall  48   b  and a cylindrical side wall  48   c . At the top wall  48   b  the liner is preferably provided with a downwardly extending lip or flange  48   d  as shown. In order to provide additional support and compensate for the relatively heavy weight of the liner, once filled with water or other liquid, and to prevent sagging or downward bulging of the bottom wall  36 , there is preferably provided an additional support member or disc  50  which may also be a foam layer whose diameter essentially corresponds to the diameter of the radial dimensions of the liner  48  when filled with fluid or other liquid  52 .  
         [0032]     The top wall  48   b  of the liner is provided with suitable closure  54  that is shown to include a male member  54   b  in the form of externally threaded neck, secured to a suitable attachment extension  54   b  which can be sealed to the lip or flange  48   d  by any suitable means such as adhesive, bonding or any other type of attachment which renders the joint resistant to escape of water or other fluid within the liner. A female member  54   c  in the form of an internally threaded cap may be used to close and seal the liner after water or fluid  52  has been added and the liner expanded as shown in  FIG. 2 .  
         [0033]     Once the liner has been filled with water or fluid  52 , an upper foam disc  56  is preferably placed between the top wall  48   b  and the top cover or flap  32  to render the bag firm and to protect the user from any sharp objects all about the entire peripheral surface of the bag.  
         [0034]     Referring to  FIG. 4 , an important feature of the invention is the provision of inner foam layers  44  which are distributed between the outer foam layer  42  and the liner  48 . In the presently preferred embodiment, the inner foam layers  44  include a series of vertically spaced expanded sections  58  each of which includes a raised portion  58   a  and recessed portion  58   b  to give the expanded sections  58  the appearance of a “dog bone”. The expanded sections  58  are vertically spaced from each other and connected by means of constricted sections  60  that link the expanded sections together and are simply in the forms of thin ribs. Clearances or gaps  62  are preferably provided between the expanded sections  58  and in the vertical hollow tubes  46  to facilitate assembly. However, it will be appreciated that using a construction of the type described provides a plurality of vertically spaced cavities  64  along the entire vertical height and interior surface of the liner or bladder  48 . The specific shapes or configurations of the expanded and constricted sections,  58 ,  60  is not critical for purposes of the present invention, as long as a plurality of cavities, of any suitable shapes, are provided essentially surrounding the entire side wall  48   c  of the liner  48 . In this manner, when the bag  10  is punched or kicked and the bag is significantly deformed at the place of impact, the water or other liquid  52  within the bag can cause portions of the liner or bladder  48  to deflect into the cavities  64  to compensate for any deformations of the bladder and displacement of the water within it. By allowing the bladder or liner  48  to at least partially expand into a plurality of cavities there is a reduced risk for rupturing the bladder or liner  48  or damaging the closure over an extended period of time. The advantages of the inner foam layers  44 , when used in conjunction with hollow tubes or other resilient longitudinally disposed members is that the liner is maintained in its desired shape while providing continued support with the added flexibility of allowing limited expansion of the liner as noted.  
         [0035]     Although the present invention has been described in some detail by way of illustration and example for purposes of clarity and understanding, it will, of course, be understood that various changes and modifications may be made in the form, details, and arrangements of the parts without departing from the scope of the invention.