Abstract:
A spring-driven reel is adapted to include a gear assembly, and a reel assembly operatively coupled to at least one gear of the gear assembly. The spring-driven reel can also include at least one spring assembly. The spring assembly can include a screw member and a non-rotatable nut moveably mounted to the screw member.

Description:
BACKGROUND 
       [0001]    Many types of spring-driven reels have been previously provided for use with cranes, hoists, etc., which employ lines or cables which supply electrical power to a traveling object. As the object is moved away from the reel, the line or cable is unwound from the spool of the reel. As the object is moved towards the reel, the spring rotates the spool to wind the line or cable onto the spool. In the past, most springs were of the “clock” type. Although the “clock” type springs do function well, the life thereof is rather limited which requires extensive disassembly of the reel to replace the spring. 
         [0002]    In an effort to overcome the shortcomings of the “clock” type springs, elongated helical or linear springs have been substituted for the “clock” type springs. U.S. Pat. No. 2,303,002 to Ruddock discloses an elongated helical spring which has one end thereof fixed to a support with the other end being rotated to twist the spring into tension as the line is pulled from the spool by the object moving away from the reel. When the object is moved towards the reel, thereby causing slack in the line, the twisted spring unwinds to rotate the spool to wind the line onto the spool. In U.S. Pat. No. 2,645,432, an improvement to the reel of U.S. Pat. No. 2,303,002 is disclosed. 
         [0003]    In both of the designs of the aforementioned patents, the rotational twisting of the helical springs eventually causes the spring to fail. 
       SUMMARY 
       [0004]    This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key aspects or essential aspects of the claimed subject matter. Moreover, this Summary is not intended for use as an aid in determining the scope of the claimed subject matter. 
         [0005]    A spring-driven reel is disclosed which can include a gear assembly, a reel assembly operatively coupled to at least one gear of the gear assembly. The spring-driven reel can also include at least one spring assembly. The spring assembly can include a screw member and a non-rotatable nut moveably mounted to the screw member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Non-limiting and non-exhaustive embodiments of the disclosure are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified. 
           [0007]      FIG. 1  is a perspective view of the spring-driven reel of this invention with the reel having two helical spring assemblies associated therewith; 
           [0008]      FIG. 2  is a perspective view of the spring-driven reel with the reel having a single helical spring assembly associated therewith; 
           [0009]      FIG. 3  is a perspective view of the spring-driven reel with the reel having four helical spring assemblies associated therewith; 
           [0010]      FIG. 4  is an exploded perspective view of the spring-driven reel of  FIG. 1 ; 
           [0011]      FIG. 5  is an exploded perspective view of the helical spring assembly; 
           [0012]      FIG. 6  is a sectional view of the helical spring assembly of  FIG. 5 ; 
           [0013]      FIG. 7  is an end view of the helical spring assembly of  FIG. 5  with the end cap thereof removed; 
           [0014]      FIG. 8  is a sectional view of the gear assembly when two helical spring assemblies are utilized; and 
           [0015]      FIG. 9  is a sectional view of the gear assembly when four helical spring assemblies are utilized. 
       
    
    
     DESCRIPTION 
       [0016]    Embodiments are described more fully below with reference to the accompanying figures, which form a part hereof and show, by way of illustration, specific exemplary embodiments. These embodiments are disclosed in sufficient detail to enable those skilled in the art to practice the invention. However, embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. The following detailed description is, therefore, not to be taken in a limiting sense in that the scope of the present invention is defined only by the appended claims. 
         [0017]    The spring-driven reel is referred to by the reference numeral  10 . The reel  10  includes one or more helical spring assemblies as will be described in detail hereinafter. Reel  10  includes a support  12  which is mounted on any convenient supporting structure in a conventional manner such as by bolts, etc. Support  12  includes a horizontally disposed base portion  14 . Support members  16  and  18  have their lower ends welded to base portion so that support members  16  and  18  are vertically disposed and are horizontally spaced-apart. 
         [0018]    A housing  20  is secured to base portion  14  and support member  18  by welding. The housing  20  includes a first end wall  22 , side wall  24 , and a second end wall  26 . The open upper end of housing  20  is selectively closed by a cover or lid  28  by bolts or screws  29 . 
         [0019]    The numeral  30  refers to a spool which is positioned between support members  16  and  18  and which is rotatable with respect thereto about a horizontal axis as will be described in greater detail hereinafter. Spool  30  includes spaced-apart flanges  32  and  34 . A plurality of spokes  36  have their ends bolted to flanges  32  and  34  so as to extend therebetween to define a drum or drum-like portion  38 . A cylindrical slip ring support  42  of convention design is secured to the outer side of support member  16  by bolts or the like. A flange bearing  44  is secured to the outer side of support member  16  by bolts. A slip ring shaft  46  is rotatably mounted in flange bearing  44  which extends through an opening  48  formed in support member  16 . Shaft  46  has a conventional slip ring assembly  50  mounted on the outer end thereof. A cover  52  is secured to slip ring support  42  in conventional fashion. 
         [0020]    The numeral  54  refers to a disc-shaped plate which has a hub  56  welded thereto. Plate  54  is bolted to the inner side of flange  32  with the hub  56  registering with an opening  58  formed in flange  32 . The inner end of shaft  46  extends through the opening  58  in flange  32  and into the hub  56 . The shaft  46  is fixed to the hub  56  by a conventional keyway and set screws so that shaft  56  rotates with flange  32  and the spool  30 . 
         [0021]    The numeral  60  refers to a disc-shaped plate having a hub  62  welded thereto. Plate  60  is bolted to the flange  34  at the inner side thereof so that the hub  62  registers with an opening  64  formed in flange  34 . A flange bearing  66  is bolted to the outer side of flange  34  at the opening  64 . A shaft  68  extends through flange bearing  66 , through opening  64  and into the hub  62 . Shaft  68  is secured to the hub  62  by a convention keyway and set screws so that shaft  68  rotates with flange  34  and spool  30 . A gear assembly  70  is provided within housing  20  and includes various gears, shafts, bearings, etc., to serve as a connection between the shaft  68  and the helical spring or springs as will be described in more detail hereinafter. 
         [0022]    Assuming that two spool retraction devices are to be used, the reel will now be described with the understanding that one or more helical spring assemblies may be used in association with the spool depending upon the length of the line or cable, the thickness of the line or cable, and the weight of the line or cable. Although the drawings illustrate a reel with a single helical spring assembly, a reel with two helical spring assemblies and a reel with four helical spring assemblies, only a single spring assembly will be described in detail with “′” indicating identical structure on the second, third and fourth helical spring assemblies and related components. If the spring-driven reel of this invention includes a single helical spring assembly, the gear assembly  70  will have a single drive shaft  72  which will be rotated by the rotation of the shaft  68  and vice versa. If two helical spring assemblies are being used, the gear assembly  70  will have two drive shafts  72  and  72 ′ which will be rotated by the rotation of shaft  68  and vice versa. The numeral  73  refers to the helical spring assembly. Helical spring assembly  73  includes an elongated, horizontally disposed tubular support  74  having an open inner end  76  which is secured to side wall  24  of housing  20  by bolts, which has an opening formed therein which communicates with the open inner end of support  74 . The outer end of support  74  is selectively closed by a cover or plate  78  bolted to support  74 . An elongated screw member  80 , preferably a conventional ball screw, is rotatably mounted in tubular support  74 . A non-rotatable nut  82 , preferably a flanged ball nut, is threadably mounted on screw member  80  within tubular support  74  adjacent the inner end of screw member  80 . The nut  82  has a square-like support  83  secured thereto which has a configuration such that it cannot rotate with respect to the support  74 . The support  83  on nut  82  has rollers  84  mounted on each of the four corners thereof with each of those rollers  84  being received by an elongated guide  86  provided in each of the corners of the support  74 . The inner end of the screw member  80  is operatively interconnected to the shaft  68 , for rotation therewith, by the gear assembly  70 . 
         [0023]    An elongated helical spring  88  embraces screw member  80  within support  74  with the inner end thereof being in engagement with the outer side of the nut  82 . To enable some tension of the spring to be preset, a plate  90  is positioned in support  74  at the outer end of spring  88 . A threaded bolt  92  extends through cover  78  with the inner end of the bolt  92  engaging the plate  90 . As the bolt  92  is threadably moved inwardly through the cover  78 , the plate  90  will engage the outer end of the spring  88  to slightly compress the spring  88  to yieldably prevent the spool  30  from rotating when in its fully retracted position. If additional spring force is required, one or more of the helical spring assemblies  73  may be used as previously stated. 
         [0024]    Assuming that only one helical spring assembly is used with the reel  10 , the reel functions as follows. Assuming that the line or cable is wound onto the spool  30 , the bolt  92  would have been previously used to move the plate  90  into engagement with the outer end of spring  88  to compress spring  88  somewhat so that the pre-set tension in spring  88  will maintain spool  80  in its retracted position. 
         [0025]    As the line or cable is pulled from the spool  30 , the spool will rotate in a first unwinding direction. The rotation of spool  30  in the first direction causes the shaft  68  to also rotate in the first direction since it is fixed to flange  34  for rotation therewith. Rotation of shaft  68  in the first direction causes screw member  80  to also rotate due to its interconnection therewith by the gear assembly  70 . As screw member  80  rotates in the first direction, the threads on the screw member  80  will cause the ball nut  82  to longitudinally move, without rotation, towards the outer end of the tubular support  74  thereby compressing spring  88  to place the spring  88  in tension. When the object to which the outer end of the line or cable moves towards the reel  10 , the line or cable becomes slightly slack. As the line or cable becomes slack, the tension in the spring  88  causes ball nut  82  to longitudinally move, without rotation, towards the inner end of the tubular support  74 . The longitudinal movement of ball nut  82  towards the inner end of the tubular support  74  causes ball screw  80  to be rotated in a winding second direction opposite to the first direction thereby causing shaft  68  and spool  30  to be rotated to take up the slack in the line or cable and winding the line or cable onto the spool  30 . 
         [0026]    As stated above, if a single helical spring assembly  73  is not sufficient enough to wind large or heavy lines or cable onto the spool  30 , additional helical spring assemblies  73  could be utilized with the gear assembly  70  driving the ball screws in those assemblies. Additional helical spring assemblies may also be needed if the line or cable is extremely long. 
         [0027]    The helical springs  88  in the helical spring assemblies  73  are much more durable than the springs of the prior art. The long life of the springs  88  results in much less repair and/or replacement. 
         [0028]    Although the specification has been described in language that is specific to certain structures and methodological steps, it is to be understood that the claims are not necessarily limited to the specific structures and/or steps described. Rather, the specific aspects and steps are described as forms of implementing the claims. Since many embodiments can be practiced without departing from the spirit and scope of the disclosure, the invention resides in the claims hereinafter appended.