Variable volume container

Abstract

A variable volume container is provided that includes a flexible tube having a wall that defines a variable volume chamber. The tube wall includes a pair of generally curved end wall portions and a pair of generally flat intermediate wall portions separated from the end wall portions by a transition wall portion. The generally flat intermediate wall portions are spaced-apart in a neutral state. A method of making a variable volume container is also provided.

1 . A variable volume container, comprising: 
 a flexible tube having a wall that defines a variable volume chamber, the tube wall including a pair of generally curved end wall portions and a pair of generally flat intermediate wall portions separated from the end wall portions by a transition wall portion, the generally flat intermediate wall portions being spaced-apart in a neutral state.    
   
   
       2 . The variable volume container of  claim 1 , wherein a height of the variable volume container proximate the intermediate wall portions is less than a height of the variable volume container proximate the end wall portions.  
   
   
       3 . The variable volume container of  claim 1 , wherein variable volume chamber includes a pair of generally bulbous end cavities and a generally rectangular intermediate cavity connecting the two end cavities in a neutral state.  
   
   
       4 . The variable volume container of  claim 1 , wherein the pair of end wall portions are defined by a first radius and the transition wall portions are defined by a second radius, the first radius being less that the second radius.  
   
   
       5 . The variable volume container of  claim 4 , wherein the flexible tube wall includes an inner surface that defines the variable volume chamber, and wherein the first radius is the radius of the inner surface included within the end wall portions of the flexible tube wall and the second radius is the radius of the inner surface within the transition wall portions of the flexible tube wall.  
   
   
       6 . The variable volume container of  claim 4 , wherein the length of the second radius is approximately twice the length of the first radius.  
   
   
       7 . The variable volume container of  claim 1  further including a reinforcing layer or a protective cover overlaying the flexible tube.  
   
   
       8 . A variable volume container comprising: 
 a flexible tube having a pair of end wall portions and a pair of generally flat intermediate wall portions separated from the end wall portions by a transition wall portion, wherein the end wall portions are defined by a first radius and the transition wall portions are defined by a second radius.    
   
   
       9 . The variable volume container of  claim 8 , wherein the first radius is less than the second radius.  
   
   
       10 . The variable volume container of  claim 8 , wherein the length of the second radius is approximately twice the length of the first radius.  
   
   
       11 . The variable volume container of  claim 8 , wherein the flexible tube wall includes an inner surface that defines a variable volume chamber, and wherein the first radius is the radius of the inner surface included within the end wall portion of the flexible tube wall and the second radius is the radius of the inner surface within the transition wall portions of the flexible tube wall.  
   
   
       12 . The variable volume container of  claim 8  further including a reinforcing layer or a protective cover overlaying the flexible tube.  
   
   
       13 . A variable volume container comprising: 
 a flexible tube wall that defines a variable volume chamber having a pair of bulbous end cavities and a generally rectangular, intermediate cavity connecting the two end cavities in a neutral state.    
   
   
       14 . The variable volume container of  claim 13 , wherein flexible tube includes a pair of end wall portions that at least partially surround the end cavities, a pair of spaced-apart and generally flat intermediate wall portions that at least partially surround the intermediate cavity, and a transition wall portion positioned between the end wall portions and the intermediate wall portions, wherein the end wall portions are defined by a first radius and the transition wall portions are defined by a second radius.  
   
   
       15 . The variable volume container of  claim 14 , wherein the flexible tube wall includes an inner surface, and wherein the first radius is the radius of the inner surface included within the end wall portion of the flexible tube wall and the second radius is the radius of the inner surface within the transition wall portions of the flexible tube wall.  
   
   
       16 . The variable volume container of  claim 13  further including a reinforcing layer or a protective cover overlaying the flexible tube.  
   
   
       17 . An variable volume container comprising: 
 a flexible tube wall including a pair of end wall portions connected to a pair of generally flat intermediate wall portions by a transition wall portion, wherein the intermediate wall portions are spaced apart in a neutral state and the transition wall portions are configured to increase the amount of flexible tube wall subjected to elastic strain during expansion of the hose and minimize the concentration of elastic strain in one or more areas of the flexible tube.    
   
   
       18 . The variable volume container of  claim 17 , wherein the flexible tube wall defines a variable volume chamber having a generally dog-bone shaped profile.  
   
   
       19 . The variable volume container of  claim 17 , wherein the flexible tube wall includes a generally dog-bone shaped profile.  
   
   
       20 . The variable volume container of  claim 17 , wherein the end wall portions are defined by a first radius and the transition wall portions are defined by a second radius, the first radius being less that the second radius.  
   
   
       21 . The variable volume container of  claim 20 , wherein the flexible tube wall includes an inner surface that defines a variable volume chamber, and wherein the first radius is the radius of the inner surface included within the end wall portion of the flexible tube wall and the second radius is the radius of the inner surface within the transition wall portions of the flexible tube wall.  
   
   
       22 . The variable volume container of  claim 17  further including a reinforcing layer or a protective cover overlaying the flexible tube.  
   
   
       23 . A method of making a variable volume container, comprising the steps of: 
 providing a generally dog-bone shaped mandrel that includes a pair of bulbous end portions having a first thickness, a generally flat, intermediate portion connecting the two end portions and having a second thickness less than the first thickness, and a transition portion connecting each of the bulbous end portions to the intermediate portion; and    applying a length of flexible tube material over the mandrel and forming a variable volume container having a variable volume chamber corresponding in approximate size and shape to the mandrel over which the flexible tube material is applied.    
   
   
       24 . The method of  claim 23  further including the step of applying a reinforcing layer or a protective cover over the flexible tube material.  
   
   
       25 . The method of  claim 23  further including the step of curing the flexible tube material after applying the length of flexible tube material over the mandrel.