Abstract:
An automated spring force adjustment assembly for a seed planter includes a screw. Also included is a spring wound around an outer surface of the screw. Further included is a nut in threaded engagement with the outer surface of the screw and in contact with the spring. Yet further included is a motor operatively coupled to the screw to rotatably drive the screw, rotation of the screw translating the nut, translation of the screw adjusting the compression of the spring.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This patent application claims priority to U.S. Provisional Patent Application Ser. No. 62/155,060, filed Apr. 30, 2015, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The embodiments described herein relate to a seed planter and, more particularly, to an automated spring force adjuster for such seed planters. 
         [0003]    Conventional planting implements currently used in farming, commonly referred to as “planters,” utilize a seed channel opener, typically in the form of a disc, that creates a channel or furrow in the soil for seed placement. Due to varying soil conditions of a field being planted, as well as different depths for different types of seeds being planted, it is desirable to adjust a spring force that assists in controlling the seed planting depth achieved during a planting operation. 
         [0004]    Adjustment of the spring force requires manual adjustment by an operator. For example, an operator must exit a tractor to go to each individual planter row unit to manually turn a large retaining nut that is operatively coupled to the spring shaft to set an estimated down force pressure for the row unit. This adjustment system undesirably leads to costly wasted time by the operator. Furthermore, the adjustment of the spring force is subject to operator error, particularly as the operator becomes fatigued throughout the planting operation. 
       SUMMARY OF THE INVENTION 
       [0005]    According to one aspect of the disclosure, an automated spring force adjustment assembly for a seed planter includes a screw. Also included is a spring wound around an outer surface of the screw. Further included is a nut in threaded engagement with the outer surface of the screw and in contact with the spring. Yet further included is a motor operatively coupled to the screw to rotatably drive the screw, rotation of the screw translating the nut, translation of the screw adjusting the compression of the spring. 
         [0006]    According to another aspect of the disclosure, an automated spring force adjustment system for a seed planter includes a controller unit. Also included is an electric motor in operative communication with the controller unit to receive a signal therefrom. Further included is a gear arrangement operatively coupled to an output shaft of the electric motor. Yet further included is a ball screw operatively coupled to the gear arrangement. Also included is a spring wound around the ball screw, the spring force controlling a seed planting depth. Further included is a ball nut in threaded engagement with the outer surface of the ball screw and in contact with the spring. 
         [0007]    These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0009]      FIG. 1  is a plan view of a tractor towing a planter; 
           [0010]      FIG. 2  is a perspective view of an automated spring force adjuster for a seed planter; and 
           [0011]      FIG. 3  is a perspective view of the automated spring force adjuster with a housing removed. 
       
    
    
     DETAILED DESCRIPTION 
       [0012]    Referring now to the Figures, where the invention will be described with reference to specific embodiments, without limiting same, an automated spring force adjuster is provided to assist in seed planting operations. 
         [0013]    Referring to  FIG. 1 , schematically illustrated is tractor  10  with a planter  12  hitched thereto. Although not illustrated in detail, the planter  12  comprises a fixed main frame having tires attached thereto for movement along the ground. The planter  12  includes a disc assembly that is used to cut a channel for a seed to be placed. The disc assembly is operatively coupled to a gauge wheel that is used to set ground penetration depth during a seed planting operation. The gauge wheel is provided to follow behind the channel and pack the soil to a desired depth. The gauge wheel is mounted to a beam arrangement. 
         [0014]    As shown, the planter  12  includes a plurality of row units  14  that are spaced from each other in a lateral direction. Each of the row units  14  translates over the ground and plants seeds at spaced intervals, and to a desired depth, along the direction of travel of the respective row unit. The desired depth is predetermined by an operator. The beam arrangement is mounted to facilitate seed planting depth control. 
         [0015]    A biasing spring  16  ( FIG. 2 ) is operatively coupled to the beam arrangement and is adjustable to adjust the force exerted by the spring  16 , thereby controlling the beam arrangement, which assists in controlling the seed depth placement, as described above. 
         [0016]    Rather than requiring manual adjustment of the spring force, the embodiments described herein provide an operator the advantages of an automated spring force adjustment system  17 . The automated system includes an electric motor  18  ( FIGS. 2 and 3 ) that is position controlled by a controller based on a signal sent from a controller unit  22 . In some embodiments the signal sent to the electric motor controller is sent in a wired manner and in alternative embodiments the signal is sent wirelessly. In one embodiment, the controller unit  22  is located onboard the tractor  10  and includes a monitor that the operator may interact with. Such an embodiment may include a touch screen that allows the operator to input commands with. Alternatively, the controller unit  22  may be operated by a wireless device, such as a tablet, laptop computer, cellular phone or the like. Regardless of the specific type of controller unit interface employed, the operator may adjust all of the spring forces of biasing spring  16  ( FIG. 2 ) for each respective individual row unit  14  at the same time and consistently. Each row unit  14  will have the same loads exerted based on the similar signal being sent to each unit. Alternatively, different rows may be adjusted with a different spring force than adjacent rows. 
         [0017]    Referring to  FIGS. 2 and 3 , the automated spring force adjustment system  17  is illustrated in greater detail.  FIG. 2  illustrates the automated spring force adjustment system  17  with a housing assembly  23 , while the housing assembly  23  is removed in  FIG. 3  to better illustrate certain features of the system  17 . The electric motor  18  is illustrated and includes an output shaft  24 . The particular type of electric motor employed may vary depending upon the particular application, but in some embodiments, the electric motor  18  is a 3-phase, 12 Volt DC motor. Irrespective of the type of motor, the output shaft  24  is operatively coupled to a worm gear arrangement  26  that is non-back drivable to drive the worm gear arrangement  26 . More particularly, the output shaft  24  is operatively coupled to a worm  28  of the arrangement  26 , which rotates a worm wheel  30  that the worm  28  is engaged with. The gear ratio of the worm gear arrangement  28  may vary depending upon the particular application, but in some embodiments a 15:1 worm gear box is employed. As shown in  FIG. 2 , the housing assembly  23  includes a gearbox housing  32  that environmentally seals the worm gear arrangement  26  to maintain operational integrity of the worm gear arrangement  26 . 
         [0018]    The worm wheel  30  is operatively coupled to, or integrally formed with, a screw (shown as a ball screw  34 ). The ball screw  34  is a hollow screw having a hollowed portion  37  that is fitted over an existing shock for dampening of the overall system in some embodiments. The biasing spring  16  is disposed about, and in contact with, an outer surface  36  of the ball screw  34 . As discussed above, adjustment (e.g., compression) of the biasing spring  16  adjusts the planting depth of seeds or the like. Adjustment of the biasing spring  16  is achieved by interaction of a nut (shown as a ball nut  38 ) with the biasing spring  16 . The ball nut  38  is in threaded engagement with the outer surface  36  of the ball screw  34 . 
         [0019]    In operation, an operator provides an input with the controller unit  22  ( FIG. 1 ) to send a signal to the electric motor  18 , which drives the worm gear arrangement  26  to rotate the ball screw  34 . Rotation of the ball screw  34  results in linear movement of the ball nut  38  in a longitudinal direction  40  of the ball screw  34 . The linear movement of the ball nut  38  compresses or relaxes the biasing spring  16  to a desired compression, which controls the planting depth. 
         [0020]    As shown in  FIG. 2 , the housing assembly  23  also includes a screw housing  42  to environmentally seal the ball screw  34 , ball nut  38  and biasing spring  16 . The screw housing  42  maintains operational integrity of the sealed components. In some embodiments, the screw housing  42  and the gearbox housing  32  are separate components. Alternatively, the screw housing  42  and the gearbox housing  32  are integrally formed to define a single, unitary housing assembly  23 . 
         [0021]    A corrugated boot  44  surrounds a portion of the ball screw  34  to allow movement of the automated spring force adjustment system  17  in a flexible manner. Based on the environmentally sealed system, a breathing feature  46  is provided proximate an end of the corrugated boot  44  to provide air exchange. This relieves pressure within the sealed regions 
         [0022]    Advantageously, the automated spring force adjustment system reduces operator time by completely eliminating manual adjustment time required by other planter systems. Furthermore, the opportunity for operator error generally, and particularly between row units, is greatly reduced. 
         [0023]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description.