Abstract:
A motorized jack assembly that is used with trailers that has a functional combination of several outputs providing different speeds for raising or lowering the jack. The jack has a drop leg feature to allow for quickly raising or lowering the jack. The motorized jack assembly has an actuator having a motor integrated with a gearbox that not only has the capacity to handle a relatively heavy load, but also have the ability to handle small and midsize loads at efficient speeds. The jack has a cover for protecting the actuator and providing user friendly controls for operating the actuator and the jack.

Description:
FIELD AND BACKGROUND OF THE INVENTION 
       [0001]    This invention generally relates to a motorized jack, and more particularly, to a motorized jack assembly having at least two outputs for raising or lowering a jack. 
         [0002]    Typically, jacks operate mechanically to raise or lower objects, such as, trailers. Jacks operating mechanically require a user to turn a crank a shaft to raise or lower the object connected to the jack, such as, a trailer. Operating the crank to raise or lower the object is not only time-consuming but also inconvenient and rigorous. As a result, there is a need for a motorized jack having lifting and lowering capabilities, ease of cranking and overall performance for both loaded and unloaded trailers. 
         [0003]    It is generally known to couple a motor to a gearbox to power a jack. However, such motors operate at one speed and cannot operate multiple jacks. Coupling the motor to the gearbox of mechanically operated jacks requires an additional gearbox. Therefore, a need exists for a motorized jack that eliminates the additional gearbox and provides easy and convenient connection to jacks. In addition, a need exists for a motorized jack having multiple output speeds. 
         [0004]    In many instances, it is desirable to have a jack that moves upward or downward at a high rate of speed when, for example, the jack is not in contact with the object to raise or lower. For example, the jack may require raising to a height to contact the trailer before raising the trailer. In such instances, there is a need for a jack operating at a high rate of speed prior to contacting the trailer. In addition, there is a need for a jack operating at a high torque as the jack begins to raise the trailer. 
         [0005]    In addition, it is oftentimes desirable to quickly provide elongation of the jack, such as in a drop leg, where there is not any mechanical cranking required in order to have a significant amount of jack elongation or contraction in a short amount of time, such as at the beginning or completion of the lifting process. 
         [0006]    Moreover, the drop leg of the jack can frequently contact the ground such that the trailer will be raised unevenly. In other words, the drop leg may abut the ground to raise one side of the trailer more than the opposite side of the trailer. Therefore, it would be advantageous to provide a jack having a level to ensure proper alignment of the jack prior to and during raising or lowering of the object, such as the trailer. 
         [0007]    Operating a jack at night or in a dark environment is difficult. For example, the drop leg of the jack may contact an object on the ground that the user is unable to see. Additionally, it is often difficult to operate the drop leg of the jack as well as other components of the jack in dark environments. Accordingly, it would be advantageous to incorporate lighting within the jack assembly. 
         [0008]    The present invention overcomes the deficiencies of the prior art by providing an actuator connectable to a jack that has two output speeds, an integrated motor and gearbox, lighting and a level. Other advantages of the present invention will be appreciate by one of ordinary skill in the art. 
       BRIEF SUMMARY OF THE INVENTION 
       [0009]    Disclosed herein is an actuator for use with a jack, such as a trailer jack. The actuator integrates a motor and a gearbox and provides at least two outputs. The first output operates at a first rate of speed providing a corresponding first amount of torque. The second output operates at a second rate of speed providing a second amount of torque. The first rate of speed is higher than the second rate of speed and the first amount of torque is less than the second amount of torque. As a result, the motorized jack efficiently and conveniently provides at least two different output speeds and at least two different amounts of torque. Advantageously, the jack can utilize a lower amount of torque before contacting a trailer and a higher amount of torque when raising the trailer. In addition, the actuator can connect to two jacks for raising or lowering, for example, landing gear of a trailer. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    The drawings illustrate the best mode presently contemplated for carrying out the invention. In the drawings: 
           [0011]      FIG. 1  illustrates a perspective view of an actuator having a first output and a second output for selectable connection to a jack to raise or lower the jack in accordance with one aspect of the present invention. 
           [0012]      FIG. 2  illustrates a perspective view of an actuator connected to a shaft of a jack in an embodiment of the present invention. 
           [0013]      FIG. 3  is a side view of a jack having a drop leg connected to an actuator in an embodiment of the present invention. 
           [0014]      FIG. 4  is a perspective view of an actuator connected to a first jack and a second jack in an embodiment of the present invention. 
           [0015]      FIG. 5  is a perspective view of a first jack connected to a first actuator and a second jack connected to a second actuator in an embodiment of the present invention. 
           [0016]      FIG. 6A  illustrates an actuator connected to a jack in an alternate orientation in an embodiment of the present invention. 
           [0017]      FIG. 6B  illustrates the actuator of  FIG. 6A  having a cover in an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Referring to  FIG. 1 , a perspective view of an actuator  3  for a jack in an embodiment of the present invention. In an exemplary embodiment, a motor  4  and a gearbox  5  are integrated in the actuator  3  such that coupling a motor to a gearbox is eliminated. The motor  4  provides input power to gearing within the gearbox  5  to output torque. The motor  4  eliminates the need for human effort to input power to the jack. In an exemplary embodiment, the motor  4  is electrically powered. 
         [0019]    The actuator  3  has a first output  7  and a second output  9 . The outputs  7 ,  9  are connectable to a shaft, such as, an axle of a trailer jack. In such an embodiment, the outputs  7 ,  9  rotate the shaft to raise or to lower the jack. A trailer may be raised or lowered by connection of the jack to the trailer. Trailers that are contemplated for use with the present invention include, but are not limited to, RV trailers, horse trailers, livestock trailers, a-frame trailer, large flatbed trailers, and construction equipment trailers. For example, the actuator  3  operates to raise or lower a jack of a RV trailer or to raise or lower an a-frame of a RV trailer. 
         [0020]    The first output  7  operates at a first rate of speed and provides a first amount of torque. The second output  9  operates at a second rate of speed and provides a second amount of torque. In a preferred embodiment, the first rate of speed is greater than the second rate of speed and the first amount of torque is less than the second amount of torque. In a most preferred embodiment, the first rate of speed is twice that of the second rate of speed and the first amount of torque is one-half of the second amount of torque. The low gear speed at the second output  9  facilitates lifting of relatively higher loads, and the working high gear speed at the first output  7  facilitates faster lifting of relatively lower and medium-sized loads or lowering relatively high loads. The actuator  3  provides different amounts of torque and different output speeds to the outputs  7 ,  9  due to different gear ratios of the gearing of the actuator  3 . The gear ratio is changed by selectably connecting the actuator  3  at the output  7  or the output  9 . 
         [0021]    The actuator  3  has apertures  10  in the gearbox  5  for mounting the actuator  3  to a jack  11 . As illustrated in  FIGS. 2 and 3 , the actuator  3  is mountable to the jack  11 , such as, an upper housing section  13  of the jack  11 . Preferably, the actuator  3  is mounted on the jack at or adjacent to a drive mechanism of the jack  11 . The drive mechanism causes telescopic movement of the jack  11  by moving the upper housing section  13  of the jack  11  with respect to a lower section  15  of the jack  11 . 
         [0022]    An axle or shaft  15  is typically connected to the drive mechanism of the jack  11 . For example, the shaft  15  engages the drive mechanism to cause telescopic movement of the jack  11 . The outputs  7 ,  9  are selectably connectable to the shaft  15  to impart rotational torque as well as translation to the jack  11 . In a preferred embodiment, one of the outputs  7 ,  9  of the actuator  3  is selectably connected to the shaft  15  to raise or lower the jack. For example, the actuator  3  is positioned such that the first output  7  engages the shaft  15  of the jack  11 . At such a position, the jack  1 I may raise at a high rate of speed relative to the second output  9 . The actuator  3  may be removed when the jack  11  is raised to a position contacting the trailer. The actuator  3  may then be positioned such that the second output  9  engages the shaft  11  to raise the jack  11  and the trailer. The second output  9  may rotate the shaft  15  at a lower rate of speed but provide more torque relative to the first output  7  to raise the trailer. 
         [0023]    Turning to  FIG. 3 , a perspective view of the actuator  3  connected to a jack  11   a  in an embodiment of the present invention is illustrated. The jack  11   a  has tubular sections  31   a ,  31   b  and  31   c . Each tubular section  31   a - 31   c  is telescopically movable to raise or to lower the jack  11   a . Rotation of shaft  15   a  translates into linear movement of jack  11   a , and more particular, the tubular section  31   a  relative to the tubular section  31   b , in order to raise and lower the jack  11   a . The tubular section  31   c  may be utilized as, for example, a drop leg to move the jack  11   a  quickly between a retracted position and an extended position in which base  33  of the jack  11   a  is in close proximity to the ground. The drop leg is in sliding, telescoping relationship with tubular section  31   b . The tubular sections  31   a - 31   c  are supported by the base  33  of the jack  11 . 
         [0024]    The tubular section  31   b  includes a pin assembly  37  having a pin  39  used to secure the drop leg into position relative to the tubular section  31   b . The drop leg may be utilized to move the base to quickly provide elongation or contraction of jack elongation in a short amount of time, such as at the beginning or completion of the lifting process. In such an embodiment, the drop leg provides the through-the-air function. As a result, the outputs  7 ,  9  do not have to provide a high speed of rotation of the shaft  15   a  to raise the jack  11   a  to satisfy the through-the-air function. 
         [0025]    With incorporation of the drop leg, each of the outputs  7 ,  9  can be utilized for lifting loads of the jack  11   a  and neither output is required to operate at a high speed that cannot carry a load. The outputs  7 ,  9  can be operator selected to lift various loads with as much speed as possible. For example, one of the outputs  7 ,  9  can operate at a higher speed (and lower torque) for relatively light loads on the jack  11   a . Likewise, one of the outputs  7 ,  9  can operate at a lower speed (and higher torque) for relatively heavier loads on the jack  11   a . In an exemplary embodiment, one of the outputs  7 ,  9  can be used to raise or lower two jacks, such as, landing gear of a trailer. Therefore, the overall efficiency of the jack  11   a  increases by reducing time required to raise and lower the jack  11   a  for more than one loading condition. 
         [0026]    The two outputs  7 ,  9  plus drop leg embodiment is particularly desired when the loads change from fully loaded to unloaded, and where loading and unloading occurs frequently, such as in vehicle or animal trailers. The outputs  7 ,  9  can serves as a working high gear and a working low gear each having a turns per inch (TPI) parameter selected at least in part to complement the drop leg. By “complement” it is meant that the TPI parameters are selected based on the anticipation of the availability of the drop leg. 
         [0027]    In another embodiment of the present invention as illustrated in  FIG. 4 , the actuator  3  is selectably connected to a first jack  11   b  and a second jack  11   c . The first jack  11   b  and the second jack  11   c  may be utilized as, for example, landing gear for a trailer, such as, an RV trailer. The actuator  3  is secured to a first jack  11   a  and connected via a shaft  15   a  to a second jack  11   c . In an embodiment, the shaft  15   a  is a hex shaft connected to one of the outputs  7 , 9  and the second jack  11   c . The outputs  7 ,  9  are selectably connected to the shaft  15   a  causing rotation of the shaft  15   a  and, in turn, raising or lowering of the first jack  11   b  and the second jack  11   c . In such an embodiment, the output  7  may raise or lower the jacks  11   b ,  11   c  at a slow rate (with high torque) and the output  9  may raise or lower the jacks  11   b ,  11   c  at a higher rate (with lower torque). Depending on the size of the load to be raised or lowered by the jacks  11   b ,  11   c , the output  9  may provide enough torque to raise or lower the jacks  11   b ,  11   c . The drop leg may be incorporated into the jacks  11   b ,  11   c . The rates of speed and amounts of torque provided by the outputs  7 ,  9  may be adjusted based on the presence or absence of the drop leg. In one such embodiment, the output  9  may be used to raise or lower the jacks  11   b ,  11   c  and the output  7  may be used to merely raise or lower one of the jacks  11   b ,  11   c . 
         [0028]      FIG. 5  illustrates an embodiment of the present invention having actuators  3   a ,  3   b  individually and independently raising and lowering the jacks  11   b ,  11   c . The actuators  3   a ,  3   b  may utilize the outputs  9  to raise and lower the jacks  11   b ,  11   c  at a higher rate of speed. In this embodiment, the jacks  11   b ,  11   c  may not require a high amount of torque due to independent connection of the actuators  3   a ,  3   b  to each of the jacks  11   b ,  11   c . 
         [0029]      FIGS. 6A and 6B  illustrate an embodiment of the actuator  3   c  orientated for use with, for example, an a-frame application. The actuator  3   c  may be used to raise and lower an a-frame attached to an RV trailer. The actuator  3   c  is rotated relative to the embodiments of the actuator  3  illustrated in  FIGS. 4 and 5 . In a typical a-frame application, for example, it may be advantageous to connect the actuator  3  at the top of the jack  11 . The present invention should not be deemed as limited to a specific arrangement of connection of the actuator  3  to the jack  11 . One of ordinary skill in the art will appreciate other arrangements of connection of the actuator  3  to the jack  11 . 
         [0030]      FIG. 6B  illustrates a cover  60  attached to the actuator  3 . The cover  60  may be made of plastic, rubber, metal or other protective material. The cover  60  may protect the actuator  3  from mechanical damage. Fasteners  61  may secure the cover  60  to the actuator  3  and/or the jack  11 . A level  63  may be connected to and/or integrated into the cover  60 . The level  63  may be, for example, a bubble level that indicates the position of the jack  11  relative to the horizon. In use, the level indicates the position of the jack  11  as the jack  11  raises or lowers relative to the ground. In a preferred embodiment, the level  63  is located at the top end of the cover  60 . A user of the jack  11  may use the level  63  to adjust the position of the jack  11  as the jack  11  raises or lowers relative to the ground. In a most preferred embodiment, the user of the jack  11  utilizes the level  63  to establish a level position of the jack  11  prior to raising the object. 
         [0031]    A light  65  is attached to the cover  60  such that the light  65  illuminates the area below the jack  11 . The light  65  may be electrically connected to a light switch  67 . To activate or deactivate the light  65  a user may engage the light switch  67 . To this end, the light  65  illuminates the jack  11  and allows effective operation of the jack  11  in operation in dark environments. 
         [0032]    A jack switch  69  is integrated and/or connected to the cover  60 . The jack switch  69  is in communication with the actuator  3  to control power, such as electricity, from a power source to the actuator  3 . In an embodiment, the jack switch  69  controls operation of the actuator  3  to raise and lower the jack  11 . In another embodiment, the cover  60  has an emergency override control  71 . In case of emergencies, such as, when it is desired to power down the jack  11 , triggering the emergency override control  71  terminates power to the jack  11 . In an embodiment, power supplied to the jack  11  is immediately stopped from reaching the actuator  3 . 
         [0033]    In another embodiment of the present invention, the cover  60  may display an emblem  70 , such as the brand name, a logo and a symbol related to the jack I  1 . The emblem  70  may be information, such as, information relating to the type of the jack  11  and the speeds and/or torque amounts of the outputs  7 ,  9  of the jack  11 . The cover  60  is removably attached or secured to the actuator  3 .  FIG. 6B  illustrates the cover  60  removed from the actuator  3  in an embodiment of the present invention. 
         [0034]    The present invention has been described with respect to several embodiments. Equivalents, alternatives, and modifications, aside from those expressly stated herein, are possible and should be understood to be within the scope of the appending claims.