Abstract:
A hydromechanical stored-energy spring mechanism is provided for acting upon high-voltage switches. The mechanism includes a drive cylinder having a piston guided therein. The mechanism also includes a piston rod which is articulated on the piston and which penetrates centrally through a cylinder block provided with a reception bore as a guide for a damping ring. The damping ring is arranged in the reception bore of the cylinder block. The outside of the damping ring bears on the cylinder block housing, and the outside of the damping ring has a protuberance.

Description:
RELATED APPLICATION 
       [0001]    This application claims priority under 35 U.S.C. §119 to German Patent Application No. 10 2008 050 674.5 filed in Germany on Oct. 7, 2008, the entire content of which is hereby incorporated by reference in its entirety. 
       FIELD 
       [0002]    The present disclosure relates to a hydromechanical stored-energy spring mechanism for acting upon high-voltage switches. 
       BACKGROUND INFORMATION 
       [0003]    Hydromechanical stored-energy spring mechanisms are used in electrical switching installations, such as for acting upon high-voltage switches. They can combine the advantages of known hydraulic drives and stored-energy spring mechanisms. On the one hand, such hydromechanical stored-energy spring mechanisms can include a spring assembly formed from cup springs and, on the other hand, can include a hydraulic drive with a hydraulic cylinder and a piston which is guided in the cylinder and on which a piston rod is articulated. In this case, the hydraulic drive, which cooperates with the spring assembly, serves to tension the springs of the spring assembly, so that the stored spring energy can be dimensioned to be sufficient to ensure as quick a separation as possible of the electrical contacts of the electrical switch. 
         [0004]    In this case, an adapted damping of the linear movement can be used to provide a controlled movement sequence. 
         [0005]    Damping can be achieved using a damping ring which is arranged on the cylinder block and surrounds the piston rod. The exact installation position of the damping ring should be taken into consideration. 
         [0006]    It has been shown that, if the damping ring is not installed exactly, a tilting of the piston rod, and consequently a destructed movement sequence of the movable parts involved, may sometimes occur when high-voltage switches in electrical switching installations are switched on and off. 
         [0007]    An inexact installation position of the cylindrical damping ring may be due to the fact that it is not inserted accurately into the reception bore on the cylinder block, but is, instead, tilted. 
       SUMMARY 
       [0008]    An exemplary embodiment provides a hydromechanical stored-energy spring mechanism for acting upon high-voltage switches. The exemplary mechanism comprises: a cylinder block having a reception bore; a drive cylinder configured to have a piston guided therein; a damping ring arranged in the reception bore of the cylinder block; and a piston rod which is articulated on said piston and which penetrates centrally through the cylinder block as a guide for the damping ring. The outside of the damping ring bears on the cylinder block housing, and the outside of the damping ring has a protuberance. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    Additional features, refinements, improvements, and advantages of the present disclosure will be explained in more detail below with reference to exemplary embodiments illustrated in the accompanying drawings, in which: 
           [0010]      FIG. 1  shows a known hydromechanical stored-energy spring mechanism with a damping ring; 
           [0011]      FIG. 2  shows an exemplary hydromechanical stored-energy spring mechanism with a damping ring according to at least one embodiment of the present disclosure; and 
           [0012]      FIG. 3  shows an enlarged perspective view of an exemplary configuration of a damping ring according to at least one embodiment of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Exemplary embodiments of the present disclosure provide a hydromechanical stored-energy spring mechanism which can operate in as fault-free a manner as possible. 
         [0014]    According to an exemplary embodiment, the hydromechanical stored-energy spring mechanism includes a damping ring, which is arranged in the reception bore of a cylinder block. The outside of the damping ring bears on the cylinder block housing, and has a protuberance on its outside surface. 
         [0015]    An advantageous aspect achieved by this exemplary configuration of the damping ring is that when the damping ring is mounted for installation, the damping ring can first be inserted easily into the cylindrical reception bore, without undesirable tilting occurring. Furthermore, it becomes possible to appropriately orient the central recess of the damping ring to receive the piston rod as a function of the respective position or orientation of the piston rod and therefore ensure an undisturbed movement sequence. 
         [0016]    According to a exemplary embodiment of the disclosure, the outside of the damping ring can have a crowned form. For example, the outer contour of the damping ring can be configured so that it has, in each case, only an approximately linear surface of contact with the reception bore. This exemplary configuration can ensure that the damping ring does not tilt under any circumstance, and thereby prevent a malfunction of the stored-energy spring mechanism. 
         [0017]    According to an exemplary embodiment of the present disclosure, the outside of the damping ring can be provided with a predetermined series of radii which can achieve a crowned outer contour. 
         [0018]    Accordingly, the outside of the damping ring can be provided with a predetermined series of chamfers, to achieve desired crowning of the outer surface of the damping ring. 
         [0019]    According to an exemplary embodiment of the present disclosure, the outer contour of the damping ring can be of a barrel-shaped design. 
         [0020]    In general, in exemplary configurations of the damping ring in a hydromechanical stored-energy spring mechanism according to the present disclosure, the damping ring can function to damp the movement sequence of the involved movable parts of the hydromechanical stored-energy spring mechanism during a switching action of high-voltage switches of electrical switching installations. 
         [0021]    When high-voltage switches of electrical switching installations are switched on or off, a damping ring can be provided for decelerating the movement of the piston rod arranged in a stored-energy spring mechanism, such as in the case of hydraulic drive cylinders of hydromechanical drives, for example. 
         [0022]      FIG. 1  shows a damping ring  10  which, according to the prior art, is arranged in the middle of a drive cylinder  12  of a hydromechanical stored-energy spring mechanism  14  between a cylinder block housing  16  and a piston rod  18  in a reception bore  20  of the cylinder block  16 . The damping ring  10  is of a circular-cylindrical design. The outer surface of the damping ring  10  therefore corresponds to the surface area of a cylinder, and the outside of the damping ring  10  bears on the cylinder block housing  16 . 
         [0023]    During a switching action of the high-voltage switch, the piston rod  18  of the hydromechanical stored-energy spring mechanism  14  is moved. The damping ring  10  is provided for decelerating or damping of the movement of the piston rod  18 . The circular-cylindrical configuration of the damping ring  10  may lead to a situation where the damping ring  10  is, for example, tilted and/or jammed in the reception bore  20  of the cylinder block  16 , and this may restrict the damping of the piston rod  18  and possibly even lead to damping failure during the switching action. 
         [0024]    Owing to the circular-cylindrical configuration of the damping ring  10 , a tilting and/or jamming of the damping ring  10  in the reception bore  20  of the cylinder block  16  may occur even when the hydromechanical stored-energy spring mechanism  14  is being assembled. 
         [0025]      FIG. 2  shows an exemplary hydromechanical stored-energy spring mechanism  21  according to at least one embodiment of the present disclosure. The exemplary hydromechanical stored-energy spring mechanism  21  includes a piston rod  18  of the hydraulic drive cylinder  12 . A damping ring  22  is arranged in the middle of the drive cylinder  12  in the reception bore  20  between the cylinder block housing  16  and the switch rod designed as a piston rod  18 . The hydraulic drive cylinder  12  of the stored-energy spring mechanism  14  operates based on the differential piston principle. 
         [0026]    According to an exemplary embodiment, the damping ring  22  serves to facilitate the deceleration of switching actions of the hydromechanical stored-energy spring mechanism  14  with the hydraulic drive cylinder  12  and with the piston rod  18  arranged in the drive cylinder  12 . In contrast to the damping ring  10  illustrated in  FIG. 1 , the outer surface of the damping ring  22  does not have a circular-cylindrical configuration in the same way as the damping ring  10  illustrated in  FIG. 1 . On the other hand, the outer surface of the damping ring  22  is provided with a crowned protuberance  24 . For example, the damping ring  22  can be designed as a concavely rounded surface instead of as the surface area of a cylinder. 
         [0027]    An exemplary embodiment provides that the damping ring  22  has a crowned protuberance  24  formed on its outside, which can provide, as compared with a cylindrical version, a better damping behavior of the hydromechanical stored-energy spring mechanism  14  during a switching action, and can be mounted in a simpler way. 
         [0028]    The damping ring  22  bears with its curved outside  24  (e.g., approximately linearly) on the cylinder block housing  16 . The outside  24  of the damping ring  22  can be designed as a crowned contour, with the result that a tilting and/or jamming of the damping ring  22  in the reception bore  20  of the cylinder block  16  during the movement of the switch rod  18  can be avoided, and the damping of the moved switch rod  22  is ensured. 
         [0029]      FIG. 3  shows an enlarged perspective view of the damping ring  22  according to according to at least one exemplary embodiment having the curved outer contour  24 . The curved outer contour  24  of the damping ring  22  is achieved by means of corresponding series of radii or of chamfers or machining contours with tangential transitions during the production of the damping ring  22 . 
         [0030]    Thus, it will be appreciated by those skilled in the art that the present invention can be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restricted. The scope of the invention is indicated by the appended claims rather than the foregoing description and all changes that come within the meaning and range and equivalence thereof are intended to be embraced therein. 
       LIST OF REFERENCE SYMBOLS 
       [0000]    
       
           10  Damping ring 
           12  Drive cylinder 
           14  Hydromechanical stored-energy spring mechanism 
           16  Cylinder block housing 
           18  Piston rod/switch rod 
           20  Reception bore 
           21  Hydromechanical stored-energy spring mechanism 
           22  Damping ring 
           24  Crowned protuberance