Abstract:
A landing gear assembly comprises a first leg member adapted to couple to a vehicle frame member, and a second member operably coupled to the first leg member and moveable between a raised storage position and a lowered in-use position. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, such that the drive mechanism extends the flexible member and moves the second leg from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second legs. In certain embodiments disclosed herein, the flexible member comprises a ribbon constructed of natural fibers. Other embodiments comprise additional pulleys and flexible members adapted to raise the second leg member from the in-use position to the raised storage position.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application claims the benefit of U.S. Provisional Application No. 60/687,781, filed Jun. 6, 2005, entitled TELESCOPING LANDING GEAR, which is hereby incorporated herein by reference in its entirety. 

   BACKGROUND OF THE INVENTION 
   The present invention relates to a no-lube telescoping, or sliding, landing gear utilizing high strength synthetic, or natural fiber ribbons or strands as support for extending or lifting an apparatus. 
   Landing gears are generally designed to have a gear system that motivates a landing portion to the ground thereby supporting an apparatus such as a trailer. Oftentimes these landing systems require frequent maintenance, including the addition of lubricants, to function properly. Additionally, to support high-weight loads, strong, heavy gearing mechanisms are required. 
   Thus, a landing gear that is lighter and stronger and functions properly without a lubricant is desired. 
   These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, and appended drawings. 
   SUMMARY OF THE INVENTION 
   One aspect of the present invention relates to a landing gear assembly that comprises a first leg member adapted to couple to a vehicle frame member, and a second leg member operably coupled to the first leg member and moveable between a raised storage position and a lowered-in use position. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, such that the drive mechanism extends the flexible member and moves the second leg from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second leg members. 
   Another aspect of the present invention is a vehicle frame assembly that comprises a vehicle frame, and a landing gear assembly. The landing gear assembly comprises a first leg member adapted to couple to a vehicle frame member, and a second leg member telescopingly coupled to the first leg member and moveable between a raised storage position and a lowered in-use position. The landing gear assembly also comprises a winch assembly including a first pulley, and a transit pulley operably coupled to the first leg member. The landing gear assembly further comprises a flexible member operably coupled with the drive mechanism and the second leg, wherein the flexible member extends from the first pulley, about the transit pulley, and is fixedly coupled to the second leg member, the drive mechanism extending the flexible member and moving the second leg member from the storage position to the in-use position, and wherein the flexible member is adapted to support a weight exerted on the first and second legs. 
   Due to the heavy weight and cumbersome nature of standard landing gears, a significant weight advantage is achieved by replacing traditional threaded rod and gear mechanisms with pulleys/rollers and fibers. The present invention provides a landing gear having fibers that are of high tensile strength and withstand fatigue and elongation. Furthermore, the fibers are resistant to heat, chemicals, and degradation without compromising excellent flexibility that is better than steel cable. Moreover, the present inventive landing gear includes an uncomplicated design, can be operated by even unskilled workers, is efficient in use, capable of a long operating life, and is particularly well adapted for the proposed use. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side elevation of a semi-trailer unhitched from an associated truck tractor, and having a landing gear thereon supporting a front end of the semi-trailer; 
       FIG. 2  is a cross-sectional front side elevation view of the landing gear taken along the line II-II,  FIG. 1 ; 
       FIG. 3  is a top cross-sectional view of the landing gear taken along the line III-III,  FIG. 2 ; 
       FIG. 4  is a front cross-sectional view of the landing gear taken along the IV-IV,  FIG. 3 ; and 
       FIG. 5  is a perspective view of an alternative landing gear assembly. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in  FIG. 1 . However, it is to be understood that the invention may assume various alternative orientations and step sequences, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are exemplary embodiments of the inventive concepts defined in the appended claims. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise. 
   The reference numeral  10  ( FIG. 1 ) generally designates a landing gear assembly embodying the present invention. In the illustrated example, the landing gear assembly  10  supports a forward end of a semi-trailer  12 . The landing gear  10  typically includes a pair of leg assemblies spaced across a width of the trailer  12  and located near respective front corners of the trailer  12 . The landing gear assembly  10  is capable of extending to engage a ground surface  14  or other supporting surface to hold up the front end of the semi-trailer  12  as is well understood in the art. A shoe  16  of the landing gear assembly  10  is pivotally mounted on a lower portion thereof for engaging the ground surface  14 . The landing gear assembly  10  is also capable of retracting to an up and out of the way position or a storage position when the semi-trailer  12  is being pulled over the road by a tractor (not shown). A crank handle  18  is used to adjust the landing gear assembly  10  between the raised storage position and the lowered in-use position, as described below. The following description is confined to the landing gear assembly  10  as illustrated in  FIG. 1 , however, it is noted that the landing gear assembly (not shown) associated and supporting an opposite side of the semi-trailer  12  is constructed and coupled to the trailer  12  in a similar manner. Such constructions are well understood by those of ordinary skill in the art and will not be further described herein. 
   The landing gear assembly  10  comprises a first leg member  20  fixedly coupled at a first end  22  to a vehicle frame member  24 , and a second leg member  26  having an interior space  28  telescopingly receiving the first leg member  20  therein. A winch assembly  30  is connected to the first end  22  of the first leg member  20  and is operably coupled to the second leg member  26  by a flexible ribbon  32 , as is described below. The winch assembly  30  is driven by a drive mechanism  34  that includes the crank handle  18 . 
   The first leg member  20  ( FIG. 3 ) includes a mounting plate portion  36  including a plurality of mounting apertures  38  that receive bolts  40  therein mounting the first leg member  28  to the vehicle frame member  24 . The first leg member  20  also includes a T-shaped slide portion  42  that telescopingly engages the second leg member  26 , as described below. The first leg member  20  further includes a pair of guide portions  44  spaced outside the slide portion  42  that guide the second leg member  26  when telescoping between the raised and lowered positions, as described below. 
   The second leg member  26  comprises a C-shaped, cross-sectional configuration including tab portions  46  that engage with the T-shaped slide portion  42  of the first leg member  20 , thereby telescopingly coupling the first leg member  20  and the second leg member  26 . The first leg member  20  and the second leg member  26  cooperate to form an interior space  48  within which the winch assembly  30  is located. The second leg member  26  further includes a longitudinally-extending pocket  50  that serves to reduce the overall weight of the landing gear assembly  10 . 
   The winch assembly  30  ( FIG. 4 ) includes a first pulley  52  operably connected to the second leg member  26  by the flexible ribbon  32 , and to the drive mechanism  34  by a gear train  54 . The drive mechanism  34  includes the manual crank handle  18  fixedly connected to an input or drive shaft  56  that is shiftable between a first position providing a first drive speed, and a second position providing a second drive speed, as described in detail in U.S. patent application Ser. No. 11/412,688, filed on Apr. 27, 2006, entitled L ANDING  G EAR AND  M ETHOD OF  A SSEMBLY , which is a divisional of U.S. application Ser. No. 10/405,079, filed on Apr. 1, 2003, entitled L ANDING  G EAR AND  M ETHOD OF  A SSEMBLY , each of which is incorporated by reference herein in the entirety. A first input gear  58  and a second input gear  60  are fixed about the drive shaft  56 . A first output gear  62  and a second output gear  64  are fixedly coupled to an output shaft  66 , and are engagable with the first input gear  58  and the second input gear  60  when the drive shaft  56  is located in position A and position B, respectively. It is noted that the gearing ratios as provided between the input gears  58 ,  60  and the output gears  62 ,  64  drive the first pulley  52  at a relatively slower and faster speed when the drive shaft  56  is located in positions A and B, respectively. 
   As best illustrated in  FIG. 2 , the flexible ribbon  32  extends from the first pulley  52  downwardly about a transit pulley  68  that is rotationally coupled to a second end  70  of the first leg member  20 , and upwardly to an end  72  that is fixedly connected to an upper end  74  of the second leg member  26 . In operation, rotating the crank handle  18  in a first direction as represented by reference numeral  76  retracts or wraps the flexible ribbon  32  about the first pulley  52 , thereby shortening the overall effective length of the flexible ribbon  32  and forcing the second leg member  26  downwardly with respect to the first leg member  20  in a direction as represented by directional arrow  78 . A second pulley  80  ( FIG. 4 ) is fixed for rotation with the drive shaft  56  and is coupled to the second leg member  26  by a second flexible ribbon  82 , wherein an end of the second flexible ribbon  82  is fixedly connected to the second leg member  26 . In operation, the second leg member  26  is retracted or moved from the lowered in-use position to the raised storage position by moving the handle  18  in a direction  84  which retracts or wraps the second flexible ribbon  82  about the second pulley  80 , thereby moving the second leg member  26  upwardly in a direction  86  with respect to the first leg member  20 . 
   The reference numeral  10   a  ( FIG. 5 ) generally designates another embodiment of the present invention, utilizing additional pulleys therein to multiply the mechanical force generated. Since the landing gear assembly  10   a  is similar to the previously-described landing gear assembly  10 , similar parts appearing in  FIGS. 2-4  and  FIG. 5 , respectively, are represented by the same, corresponding reference numeral, except for the suffix “a” in the numerals of the latter. In the illustrated example, the second leg member  26   a  is telescopingly received within the first leg member  20   a . The flexible ribbon  32   a  extends downwardly from the first pulley  52   a  of the winch assembly  30   a , about a first transit pulley  68   a  pivotally coupled to a distal end  88  of the first leg member  20   a , about a second transit pulley  92  that is pivotally connected to the upper end  74   a  of the second leg member  26   a , and is fixedly connected at an end  94  to the distal end  88  of the first leg member  20 . The landing gear assembly  10   a  further includes return mechanisms similar to that previously described with respect to the landing gear assembly  10 . In operation, the landing gear assembly  10  operates in a similar manner to that of the landing gear assembly  10  as previously described. 
   Due to the heavy weight and cumbersome nature of standard landing gears, a significant weight advantage is achieved by replacing traditional threaded rod and gear mechanisms with pulleys/rollers and fibers. The present invention provides a landing gear having fibers that are of high tensile strength and withstand fatigue and elongation. Furthermore, the fibers are resistant to heat, chemicals, and degradation without compromising excellent flexibility that is better than steel cable. Moreover, the present inventive landing gear includes an uncomplicated design, can be operated by even unskilled workers, is efficient in use, capable of a long operating life, and is particularly well adapted for the proposed use. 
   In the foregoing description, it will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed herein.