Patent Publication Number: US-6655541-B2

Title: Storage container for liquids

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a storage container for liquids, in particular, flammable liquids such as fuel oil, used oil, lubricating oil, and diesel fuel, the container comprising an inner container to be filled with the liquid and made of plastic material and a receptacle made of plastic material in which the inner container is received for leak-proofing the inner container, wherein an intermediate space is formed between the inner container and the receptacle. 
     2. Description of the Related Art 
     Storage containers of this kind, as they are known from European patent 0 901 972 B1, are used primarily for storing fuel oil in buildings. Because of the configuration of the storage container comprising a collecting receptacle for leak-proofing the inner container, it is no longer necessary to build a protective wall at the site where the storage container is to be set up or to provide a separate collecting container. In the known storage container, the upper edge of the tub-shaped receptacle is located at the level of the fill socket, the removal socket, and the venting socket of the inner container, and the receptacle is connected with its upper edge to the inner container for providing a gas-tight enclosure of the intermediate space between the receptacle and the inner container. For increasing the shape stability and the static load capacity, the sidewalls of the inner container and of the receptacle are provided across the entire container height with groove-shaped peripheral recesses. 
     The construction of such known storage containers is relatively complex, and the manufacture of the container is accordingly expensive. A further disadvantage of the storage container resides in that the transport to the respective set-up location is cumbersome. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to develop a storage container for liquids of the aforementioned kind such that is characterized by a simple construction, an inexpensive manufacture, and excellent transportability. 
     In accordance with the present invention, this is achieved in that the inner container of the storage container, which is formed as a sectioned container, is comprised of at least two container parts which container parts are formed as a monolithic part by blow molding and are connected with one another by a groove-shaped vertical recess extending in the sidewalls, the bottom, and the top of the inner container, wherein the receptacle has an insertion opening for the inner container, wherein the inner container projects with the top portions of the two container parts through the insertion opening of the receptacle in the upward direction away from the receptacle, wherein the sidewalls and the receptacle bottom of the receptacle have a groove-shaped vertical recess which is matched to the recess of the sidewalls and the container bottom of the inner container, and wherein the storage container is reinforced by a peripheral vertical strap which engages the vertical recesses of the inner container and of the receptacle. 
     The storage container according to the invention is characterized by a simple configuration, low manufacturing costs, low weight, a minimal space requirement as a result of the compact shaping, a high safety as a result of the receptacle provided for liquid which may leak from the inner container, the use of a shape-integrated steel pipe strap for increasing the shape stability, an excellent long-term stability, an absolute corrosion resistance and freedom of maintenance because of blow molding of the inner container and of the receptacle of high-pressure process polyethylene, and excellent transportability by optionally furnishing the storage container with a steel pipe pallet or a transport and storage frame. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     In the drawing: 
     FIG. 1 is a perspective illustration of a storage container according to the invention; 
     FIG. 2 is a central vertical section of the storage container of FIG. 1; 
     FIG. 3 is a detail view of the storage container according to the detail III of FIG. 2; 
     FIG. 4 is a perspective illustration of the inner container of the storage container according to the invention; 
     FIG. 5 is a perspective illustration of the receptacle of the storage container according to the invention; 
     FIG. 6 is a side view of a storage container fastened on a transport pallet; 
     FIG. 7 is an end view of the storage container of FIG. 6; 
     FIG. 8 is a perspective illustration of the transport pallet of the storage container according to FIGS. 6 and 7; 
     FIG. 9 is a perspective illustration of a storage container provided with a transport and storage frame; and 
     FIG. 10 is a schematic illustration of a leak indicator of the storage container. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The storage container  1  according to FIGS. 1 through 5, which is embodied as a sectional container and is designed for storing fuel oil or heating oil, has as a main component an inner container  2  made of plastic material for receiving the heating oil as well as a receptacle  4  made of plastic material and surrounding the inner container  2  for leak-proofing the inner container  2 . An intermediate space  3  is formed between the inner container  2  and the receptacle  4 . 
     The inner container  2  is comprised of two identical container parts  2   a ,  2   b , which are blow-molded as monolithic parts of plastic material, preferably polyethylene, and are connected with one another by a groove-shaped, vertical recess  5  of the sidewalls  6 ,  7 , the container bottom  8 , and the top  9  of the inner container  2 . 
     The receptacle  4  has an insertion opening  10  for the inner container  2 . The inner container  2  projects with the upper portions  11 ,  12  of the two container parts  2   a ,  2   b  through the insertion opening  10  of the receptacle  4  in the upward direction away from the receptacle  4 . 
     A groove-shaped vertical recess  16  is formed in the two sidewalls  13 ,  14  and the receptacle bottom  15  of the receptacle  4  and matches the recess  5  provided in the sidewalls  6 ,  7  and in the container bottom  8  of the inner container  2 . 
     The storage container  1  is reinforced by a peripheral vertical strap  17  which engages the vertical recesses  5 ,  16  of the inner container  2  and of the receptacle  4  and is comprised of two U-shaped pipes  18 ,  19  made of steel and insertable into one another. 
     The sidewalls  13 ,  14  and the end walls  20 ,  21  of the receptacle  4  have groove-shaped circumferential recesses  22  distributed across the height of the receptacle for increasing the shape stability of the receptacle  4  and for supporting and centering the inner container  2  as well as for forming the intermediate space  3  between the receptacle  4  and inner container  2  provided for receiving the liquid which may leak from the inner container  2 . 
     On the upper opening rim  23  of the receptacle  4  a peripheral grip edge  24  is provided for handling the storage container  1  and for attachment of a shrinking foil for protection of the fill and removal fixtures connected to the fill and removal sockets  25 ,  26  of the storage container  1  during transport of the container. 
     When manufacturing the receptacle  4 , the upper container part of the monolithic blow-molded container is cut off. 
     The inner container  2  has grip depressions  29  on the end walls  27 ,  28 , and drop handles  30  are provided on the end walls  20 ,  21  of the receptacle  4 . 
     The storage container  1  illustrated in FIGS. 6 and 7 is provided with a transport and storage pallet  31  according to FIG. 8 which is embodied as a steel pipe pallet. The storage container  1  is connected by means of the reinforcement strap  17  with screws to supports  32  on the two longitudinal sides of the transport pallet  31 . 
     The storage container  1  according to FIG. 9 is provided with a transport and storage frame  33  which is formed of a pallet  34  with four vertical corner posts  35  which extend into the area of the insertion opening  10  of the receptacle  4 . The upper ends  36  are provided with an opening  37  for hooking the gear hook of a lifting device such as a crane. The upper ends  36  of the four corner posts  35  of the pallet  34  are connected to one another by a single-part or four-part reinforcement frame  38  (as illustrated). The frame  38  is fastened by a screw  40  on a stay  39  above the hook opening  37  of the four corner posts  35 , respectively. The hook openings  37  of the four corner posts  35  of the transport and storage frame  33  have a triangular shape that widens in the upward direction so that a crane hook can be suspended from the openings  37  without being impaired by the fastening screw  40  of the reinforcement frame  38   
     The pallet  34  of the transport and storage frame  33  is comprised of a base frame  41 , four corner legs  42  on which the corner posts  35  are fastened, two center legs  43  as well as an upper frame  44  fastened on the corner and center legs  42 ,  43 . The frame  44  has transverse members for supporting a flat pallet bottom  45  on which the storage container  1  is positioned. 
     The storage container  1  can be provided by the manufacturer with an optical and acoustic leak indicator  46  or can be retrofitted later on by the operator with such a device. The leak indicator  46  is provided with a measuring sensor  47  which, together with a weight  48 , is suspended on an electrical transmission cable  49  in the intermediate space  3  between inner container  2  and the receptacle  4  to the receptacle bottom  15  of the receptacle  4  and is fastened by means of a strain relief device  50  on the upper rim  23  of the opening of the receptacle  4 . In a leak situation, a control signal is sent by the measuring sensor  47  to an alarm device (not illustrated) connected to the transmission cable  49 . The alarm device has optical and/or acoustic indicators such as an illuminating indicator and a buzzing alarm which are activated by the control signal. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.