Patent Publication Number: US-7908851-B2

Title: Hydraulic energy storage with reinforced layer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 11/837,383 filed on Aug. 10, 2007 now U.S. Pat. No. 7,677,036 which was a continuation-in-part of U.S. patent application Ser. No. 11/829,732 which was filed on Jul. 27, 2007 now abandoned and entitled Expandable Vehicle Frame. U.S. patent application Ser. No. 11/829,732 is a continuation-in-part of U.S. patent application Ser. No. 11/773,561 which was filed on Jul. 5, 2007 now U.S. Pat. No. 7,891,453 and entitled Energy Storage in an Elastic Vessel. U.S. patent application Ser. No. 11/773,561 is a continuation-in-part of U.S. patent application Ser. No. 11/772,334 which was filed on Jul. 2, 2007 now U.S. Pat. No. 7,600,376 and entitled Energy Storage. This application is inhere incorporated by reference for all that is discloses. 
    
    
     BACKGROUND OF THE INVENTION 
     The current invention relates to hydraulic systems for performing work. Hydraulic systems are used in many different applications such as automobiles, trucks, construction equipment, elevators, submarines, and many others. Hydraulic systems may be used to improve such areas as fuel efficiency and power output of mechanical systems which require energy to perform various forms of work, such as lifting payloads, propelling vehicles, or raising elevators. In some applications, it may be desirous to have energy storage in the hydraulic system to provide extra energy when needed. 
     In hydraulic circuits, hydraulic accumulators have been used to store excess hydraulic fluid. These hydraulic accumulators may comprise an elastic bladder within a rigid chamber. A compressible medium such as a gas may be disposed within the chamber outside of the elastic bladder, while the hydraulic fluid may be disposed within the elastic bladder. When the volume of hydraulic fluid in the bladder increases, the bladder compresses against the compressible medium thereby generating a potential energy within the rigid chamber which is stored outside of the elastic bladder. 
     U.S. Pat. No. 6,807,988 to Powell et al., which is herein incorporated by reference for all that it contains discloses a flexible hose adapted construction for conveying fluids under pressure. The construction includes a core tube having a circumferential inner core tube surface. A first reinforcement layer surrounds the outer core tube surface, and is formed of one or more filaments of a first fiber. A second fiber reinforcement layer surrounds the first reinforcement layer, and is formed of one or more filaments of a second fiber. The first and second reinforcement layers are bonded together by means of a bonding agent such as an adhesive, resin, plasticizer, tackifier, or solvent, the application of which is controlled to wet on a portion of the filaments of the reinforcement layers. 
     U.S. Pat. No. 5,042,532 to Gilleland, which is herein incorporated by reference for all that it contains discloses a pipeline repair and leak sealing system effected by unrolling a tube, using an inflatable mandrel disposed inside the tube, to radially expand a stretchable and circumferentially continuous gasket or sealant sleeve into flush contact with the pipeline interior. Before actuation, the tube is constrained in a rolled-up condition by a shrink-wrap sleeve of plastic film that may be sealed at its ends to an interior film sleeve in order to protect the tube against moisture. When fully expanded, the tube includes longitudinally-extending edges that overlap and are secured together by adhesive issued from a rupturable package disposed proximate one of the edges so as to be caused to burst as the edges approach overlapped positions. An outer sleeve of scrim material surrounds the tacky or gum-like gasket sleeve to facilitate handling and movement of the assembly in the pipeline. When the tube and gasket sleeve are expanded, the scrim material becomes embedded in the tacky gasket sleeve material which thereby protrudes through the scrim interstices to assure proper sealing and compression of the gasket sleeve against the pipeline interior wall. 
     U.S. Pat. No. 4,733,603 to Kukolj, which is herein incorporated by reference for all that it contains discloses an actuator that has a first connection point and a second connection point at opposite ends and is contractible along an axis extending between the connections points. The actuator has at least one hollow enclosure with an opening for admitting a pressurized fluid. A simultaneously radially expandable, axially contractible constraining means cooperates with the enclosure. The constraining means converts radial expansion of the actuator into axial contraction when pressurized fluid is admitted into the enclosure. In a preferred form, the constraining means comprises a network of non-stretchable, flexible tension links. 
     BRIEF SUMMARY OF THE INVENTION 
     In one aspect of the present invention, a system for performing work has a hydraulic circuit adapted to store energy within a hose. The hose has an elastic inner layer pre-tensioned by a radial tensioning component disposed within the hose and at least one reinforcing layer of elastic thread disposed around and compressing the inner layer. A hydraulic fluid is in the circuit and in communication with the hose, the radial tensioning component and a hydraulic actuator for doing the work. The circuit has a mechanism for pressurizing the hydraulic circuit in order to perform the work. 
     In some embodiments, the at least one reinforcing layer of elastic thread may comprise a total thickness of the thread. The at least one reinforcing layer of elastic thread may comprise a total thickness of ten times the thickness of the thread. The elastic thread may be braided, interwoven, wrapped and/or combinations thereof. The elastic thread may have a modulus of elasticity of rubber. The at least one reinforcing layer may comprise a material selected from the group consisting of composite material, polyurethane, polyethylene, rubber, synthetic polymers, chloroprene, elastomers, silicone rubber, rubber foam, or a combination thereof. 
     The inner layer may comprise a material selected from the group consisting of composite material, Kevlar, polyurethane, polyethylene, Twaron, aramid fiber, nylon, rubber, carbon, synthetic polymers, chloroprene, elastomers, polyester, silicone rubber, rubber foam, carbon fiber, glass fiber, cloth or a combination thereof. 
     The radial tensioning component may be segmented. The radial tensioning component may comprise a perforated pipe. The radial tensioning component may comprise a spring, a frame, or combinations thereof. 
     The hose and radial tensioning component may be enclosed within a low pressure reservoir of the hydraulic circuit. The hose may have an outer diameter of 0.9 to 1.75 inches. 
     The hydraulic circuit may be adapted to store at least 50 foot pounds of energy within the hose. A material of the hose may store at least 85% of the energy. The hydraulic fluid may be compressible and at least 10% of the energy may be stored in the hydraulic fluid. A compressible element may be disposed within the hose and at least 15% of the energy may be stored in the compressible element. 
     The hose may be inflated with hydraulic fluid to over 1,000 psi. The hose may be inflated with hydraulic fluid to over 6,000 psi. 
     The system may be incorporated in an automobile, golf cart, a truck, an elevator, backhoe, bulldozer, trencher, milling machine, a boat, construction equipment, or a combination thereof. 
     In one aspect of the present invention, a hose for storing energy may comprise an elastic inner layer pre-tensioned by a radial tensioning component disposed within the hose and at least one reinforcing layer of elastic thread disposed around and compressing the inner layer. A hydraulic fluid may be in communication with the hose and with the radial tensioning component. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective diagram of an embodiment of an automobile. 
         FIG. 2  is a cross-sectional diagram of an embodiment of a system for performing work. 
         FIG. 3  is a cross-sectional diagram of another embodiment of a system for performing work. 
         FIG. 4  is a perspective cross-sectional diagram of an embodiment of a hose. 
         FIG. 5  is a perspective cross-sectional diagram of another embodiment of a hose. 
         FIG. 6  is a perspective cross-sectional diagram of another embodiment of a hose. 
         FIG. 7  is a perspective cross-sectional diagram of another embodiment of a hose. 
         FIG. 8  is a perspective cross-sectional diagram of another embodiment of a hose. 
         FIG. 9  is a cross-sectional diagram of another embodiment of a system for performing work. 
         FIG. 10  is a cross-sectional diagram of another embodiment of a system for performing work. 
         FIG. 11  is a cross-sectional diagram of another embodiment of an automobile. 
         FIG. 12  is a perspective diagram of another embodiment of an automobile. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENT 
     The current invention may be incorporated into a vehicle  100  such as an automobile, as in the embodiment of  FIG. 1 . The vehicle may comprise a frame  108 , an engine  107 , translation assemblies  103 , a hydraulic pump  104 , a plurality of manifolds  102 , and a hose assembly  101 . The hose assembly  101  may be in communication with the plurality of manifolds  102 . The manifolds  102  may be disposed proximate the translation assemblies. The translation assemblies  103  may be in mechanical communication with individual hydraulic actuators disposed within the manifolds  102 . When the vehicle  100  brakes, energy may be captured and stored in the hose assembly  101 . The hydraulic pump  104  may be in communication  110  with the engine  107  and the hose assembly  101 . The hydraulic pump  104  may transfer energy from the engine  107  to the hose assembly  101 . The hose assembly  101  may be incorporated into at least one of the axles  109  of the vehicle  101 . 
     Referring now to  FIG. 2 , the hose assembly  101  may comprise at least one high pressure reservoir  202  disposed within a low pressure reservoir  201 . The low pressure reservoir  201  may comprise an elastic tube  205  disposed intermediate a front mandrel  203  and a rear mandrel  206 . A clamping mechanism  204  may be utilized to connect the elastic tube  205  to the front mandrel  203  and to the rear mandrel  206 . The front mandrel  203  may comprise a low pressure port  207  adapted to allow hydraulic fluid  313  to enter and exit the low pressure reservoir  201 . The front mandrel  203  may comprise a high pressure port  208  adapted to allow hydraulic fluid  313  to enter and exit the high pressure reservoir  202 . When the hydraulic fluid  313  is expelled from the high pressure reservoir  202  and enters the low pressure reservoir  201  the elastic tube  205  may expand radially to accommodate the hydraulic fluid  313 . The tube  205  may store the hydraulic fluid  313  at a pressure of 190 psi to 300 psi. The tube  205  may comprise a material selected from the group consisting of composite material, Kevlar, polyurethane, polyethylene, Twaron, aramid fiber, nylon, rubber, carbon, synthetic polymers, chloroprene, elastomers, polyester, silicone rubber, rubber foam, carbon fiber, glass fiber, cloth or a combination thereof. The tube  205  may have a modulus of elasticity of rubber. 
     The tube  205  may have a diameter of 8 inches to 15 inches. The diameter of the tube  205  may be approximately ten times larger than a diameter of the high pressure reservoir  202 . The tube  205  may be rigid. 
     Referring now to  FIG. 3 , the front mandrel  203  may comprise a corrugated surface  314  to enhance the connection between the front mandrel  203  with the elastic tube  205 . The rear mandrel  206  may comprise a corrugated surface  314  to enhance the connection between the rear mandrel  206  with the elastic tube  205 . 
     The high pressure reservoir  202  may be adapted to store at least 50 foot pounds of energy. The at least one high pressure reservoir  202  may comprise a radial tensioning component  301  disposed within a hose  302 . The radial tensioning component  301  may comprise a rigid perforated pipe  301 . A material of the hose  302  may store at least 85% of the energy. At least 10% of the energy may be stored in the compressible hydraulic fluid  313 . The hose  302  may have an outer diameter of 0.9 to 1.75 inches before pressurization. The hose  302  may be inflated with hydraulic fluid to over 1,000 psi. The hose  302  may be inflated with hydraulic fluid to over 6,000 psi. 
     The hose  302  may comprise an elastic inner layer  303  pre-tensioned by the radial tensioning component  301 . The inner layer  303  may comprise a material selected from the group consisting of composite material, Kevlar, polyurethane, polyethylene, Twaron, aramid fiber, nylon, rubber, carbon, synthetic polymers, chloroprene, elastomers, polyester, silicone rubber, rubber foam, carbon fiber, glass fiber, cloth or a combination thereof. 
     At least one reinforcing layer of elastic thread  304  may be disposed around and compressing the inner layer  303 . The at least one reinforcing layer of elastic thread  304  may comprise a total thickness of the thread. Preferably the at least one reinforcing layer of elastic thread  304  may comprise a total thickness of ten times the thickness of the thread. The elastic thread may have a modulus of elasticity of rubber. The at least one reinforcing layer  304  may comprise a material selected from the group consisting of composite material, polyurethane, polyethylene, rubber, synthetic polymers, chloroprene, elastomers, silicone rubber, rubber foam, or a combination thereof. The at least one reinforcing layer  304  may be covered by an elastic layer  305  that may provide protection to the reinforcing layer  304 . 
     Both the ends of the hose  302  and the ends of the radial tensioning component  301  may be connected via couplings  306  to the front mandrel  203  and the rear mandrel  206  disposing the hose  302  and the radial tensioning component  301  intermediate the front mandrel  203  and the rear mandrel  206 . The radial tensioning component  301  may be connected to the couplings  306  by a right-handed threaded connection  311  or by a left-handed threaded connection  311 . The couplings  306  may be connected to the front mandrel  203  or the rear mandrel  206  by a right-handed threaded connection  310  or by a left-handed threaded connection  310 . 
     O-rings  308  may be disposed intermediate the radial tensioning component  301  and the couplings  306 . An o-ring  308  may be disposed intermediate the coupling  306  and the front mandrel  203  to help prevent hydraulic fluid  313  from leaking out of the high pressure reservoir  202  to the low pressure reservoir  201 . An o-ring  308  may be disposed intermediate the coupling  306  and the rear mandrel  206  to help prevent hydraulic fluid  313  from leaking out of the high pressure reservoir  202  to the low pressure reservoir  201 . 
     Fittings  307  may be disposed around the connection between the couplings  306  and the hose  302 . The fittings  307  may apply pressure on the ends of the hose  302  causing the ends of the hose  302  to be pinched between the fittings  307  and the radial tensioning component  301 . The fittings  307  may expand in diameter as the fittings  307  extend away from the couplings  306 . It is believed that the expansion in diameter in the fittings  307  will accommodate the hose  302  as the hose  302  expands in diameter when hydraulic fluid  313  is pumped into the high pressure reservoir  202  from the low pressure reservoir  201 . 
     Referring to  FIGS. 4 through 5 , the reinforcing layer  304  may comprise elastic thread that is interwoven, wrapped, braided and/or combinations thereof. It is believed that braiding or interweaving the elastic thread may give the reinforcing layer  304  added strength and may prevent the inner elastic layer  303  from bulging through the reinforcing layer  304  as the hose  302  expands in diameter with the inflow of hydraulic fluid  313  into the high pressure reservoir  202 . The hose  302  may comprise multiple reinforcing layers  304  such as the embodiment disclosed in  FIG. 4 . 
       FIG. 6  discloses another embodiment of the present invention wherein the reinforcing layer  304  may comprise layers of thread that differ one from the other in wrapping style. At least two of the differing layers may be wrapped in directions that oppose one  601  another  602 . The thread may be wrapped at an angle. 
     The radial tensioning component  301  may comprise a spring  301 .  FIG. 7  discloses another embodiment of the present invention wherein the radial tensioning component  301  may comprise a frame  301 . 
     Referring now to  FIG. 8 , a compressible element  801  may be disposed within the hose. It is believed that the compressible element  801  may assist the hose  302  in storing energy when the high pressure reservoir  202  is pressurized. At least 15% of the energy may be stored in the compressible element  801 . 
     Referring now to  FIG. 9 , the radial tensioning component  301  may be segmented. It is believed that the segmented radial tensioning component  301  may facilitate the assembly process of the hose assembly  101 . 
     The high pressure reservoir  202  may comprise a rounded end  1002  such as in the embodiment disclosed in  FIG. 10 . The rear mandrel  206  may have a recess  1001  adapted to receive the rounded end  1002  of the high pressure reservoir  202 . The recess  1001  may be large enough to permit the hose  302  portion of the round end  1002  to expand within the recess when the high pressure reservoir  202  is pressurized. 
     Referring now to  FIG. 11 , the high pressure reservoir  202  may be disposed outside the low pressure system  201 . The high pressure reservoir  202  and the low pressure reservoir  201  may be incorporated into the frame  108  of the vehicle  100  such as the embodiment disclosed in  FIG. 12 . 
     Whereas the present invention has been described in particular relation to the drawings attached hereto, it should be understood that other and further modifications apart from those shown or suggested herein, may be made within the scope and spirit of the present invention.