Abstract:
A hopper door opening and closing apparatus operates a door on a hopper discharge opening. A pair of motorized linear actuators, each having an extendable rod, are mounted to support rails on opposite sides of the door. A bracket connects the rods to the door. A controller selectively activates the linear actuators to extend the rods and thereby move the door to an open position that permits material to flow through the lower opening and selectively activates the linear actuators to retract rods and thereby move the door to a closed position covering the lower opening.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a conversion of U.S. Provisional Application Ser. No. 62/255,557, filed Nov. 16, 2015, of which is herein incorporated by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates generally to mechanisms for opening a hopper door on a trailer, and more particularly, to automated mechanisms for opening the hopper door for a particulate material trailer. 
       BACKGROUND OF THE INVENTION 
       [0003]    A hopper trailer is a trailer that includes one or more hoppers defined within the trailer body. Each of the hoppers includes a discharge opening through which grain, or other loose granular material may flow in order to empty the trailer. The discharge opening at the lower end of the hopper is typically provided with a door that can be selectively opened and closed by a user to permit flow through the discharge opening or to prevent flow through the discharge opening. In a conventional design, the door slides in a generally horizontal plane to open and close the discharge opening. 
         [0004]    One disadvantage of the conventional sliding door design is that it is difficult to move the door when the trailer is fully loaded with grain or other bulk materials. According to a conventional design a hand crank is provided to allow a user to move the sliding door back and forth between the open and closed positions. However, it can be difficult and inconvenient to manually provide the necessary force to move the sliding door. 
         [0005]    Automated designs powered by hydraulics have been proposed. However, these hydraulic designs have some disadvantages. They require significant hardware and expertise to connect to a hydraulic system. They can be noisy during operation, and require pressure to be maintained in the hydraulic lines even when not in operation. There is a need for an improved automated design that does not utilize hydraulics. 
         [0006]    Accordingly, a primary objective of the present invention is the provision of an improved door opening and closing apparatus for a particulate material trailer hopper door. 
         [0007]    Another objective of the present invention is the provision of a motorized linear actuator connected to a door of a particulate material container to control opening and closing of the door. 
         [0008]    A further objective of the present invention is the provision of a method of moving a granular material hopper door between open and closed positions. 
         [0009]    Yet another objective of the present invention is the provision of a method and means for remotely operating a door of a grain trailer discharge chute. 
         [0010]    Still another objective of the present invention is the provision of an apparatus for quickly, easily and safely opening and closing a discharge door of a particulate material container. 
         [0011]    These and other objectives will become apparent from the following description of the invention. 
       SUMMARY OF THE INVENTION 
       [0012]    According to one embodiment, the present invention relates to a hopper door opening and closing apparatus for opening and closing a door located at a lower opening of a granular or particulate material hopper. A pair of support rails are mounted to opposite sides of the hopper. A pair of linear actuators each having an electric motor electrically connected to a power source and each having an extendable and retractable actuator rod are mounted to the support rails. A bracket is operably attached to the door and has a central portion with end portions extending from the central portion. The end portions include vertically extending portions that extend from the central portion to a height above a top edge of the rails The end portions also include lateral portions that extent outward beyond outer faces of the rails, and tabs that the attach the lateral portions to the rods, such that the bracket connects the rods to the door. A controller selectively activates the linear actuators to extend the rods and thereby move the door to an open position that permits material to flow through the lower opening, and selectively activates the linear actuators to retract the rods and thereby move the door to a closed position covering the lower opening. The apparatus may include a remote control, wherein the linear actuators are controllable with the remote control. Motor guards may be mounted to the support rails to protect the motors. 
         [0013]    The invention also encompasses a method of operating the door of a discharge chute on a particulate material hopper. The method involves actuating a motor to extend and retract a linear actuator connected to the door so as to move the door between open and closed positions. The method may be conducted remotely using a remote control device. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is side elevation view of a truck trailer with an open top, and having a cover tarp and two discharge chutes and openings, and with the door opener of the present invention. 
           [0015]      FIG. 2  is a close up view of a hopper door opening and closing apparatus according to one embodiment of the present invention, with the actuator extended to open the hopper door. 
           [0016]      FIG. 3  is another close up view of the hopper door opening and closing apparatus of the present invention, with the door in an open position. 
           [0017]      FIG. 4  is an enlarged view of the bracket of the apparatus. 
           [0018]      FIG. 5  is another enlarged view of the electric motor of the door opener and closer apparatus. 
           [0019]      FIG. 6  is a perspective view of the hopper door opening and closing apparatus, with the actuator in a retracted position to close the door. 
           [0020]      FIG. 7  is a perspective view of an alternative embodiment of a hopper door opening and closing apparatus that includes a motor guard. 
           [0021]      FIG. 8  is a left side perspective view of the hopper door opening and closing apparatus of  FIG. 7 . 
           [0022]      FIG. 9  is another perspective view of the hopper door opening and closing apparatus of  FIG. 7 . 
           [0023]      FIG. 10  is a right side perspective view of the door opening and closing apparatus shown in  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]      FIG. 1  shows a hopper trailer  10  including a storage compartment  12  that is suited for containing grain, coal, fertilizer, gravel, sand, or other loose, solid, flowable particulate or granular material. The lower portion of the storage compartment  12  is provided with hopper chutes  14 . The hopper chutes  14  act as funnels to guide the flow of granular material (not shown) within the storage compartment  12  through discharge openings (not shown) at the lower ends of the hopper chutes  14 . The hopper trailer  10  of  FIG. 1  includes a kingpin structure  18  that is adapted to be connected to the fifth wheel of a truck (not shown) or other towing vehicle. Collapsible and foldable jacks  20  are provided to support the hopper trailer  10  when it is not connected to a towing vehicle. 
         [0025]    The present invention is directed toward a hopper door opening and closing apparatus  16  provided on each of the hopper chutes  14 . The hopper door opening and closing apparatus  16  provides a mechanism for controlling the flow of the granular material through the discharge openings. 
         [0026]    Additional details of the hopper door opening and closing apparatus  16  can be seen in  FIGS. 2-6 . A pair of support rails  22  are mounted at a lower portion of each chute  14  on opposite lateral sides of the chute  14 . One of the rails  22  is mounted on the driver side of the chute  14  and the other is mounted on the passenger side. The rails  22  are elongated metal beams that act as mounting and support structures for linear actuators  24 . The rails  22  may be attached to the chutes by bolts, rivets, or the like. In many instances the rails  22  will be existing structure used to support the sliding hopper door  34 . 
         [0027]    Electric motors  26  are provided at one end of each of the linear actuators to selectively extend and retract corresponding output rods or arms  28 . The free ends of the two output rods  28  are attached to a bracket  30  that extends between and connects the free ends of the two output rods  28 . The bracket  30  includes a lower central portion  32  that attaches to the hopper door  34  and end portions  36  that connect the central portion  32  with the output rods  28 . The end portions  36  extend vertically upward from the lower central portion  32 , laterally outward beyond the width of the support rails  22  and, and vertically downward to connect with the free ends of the output rods  28 . The end portions  36  attach to the rods  28  preferably by an easily detachable connector, such as a bolt. In the embodiment shown, the lower central portion  32  along with the adjacent vertical and lateral portions are formed from a single piece of metal bent to the desired shape, and separate metal tabs  38  are welded to that piece of metal to act as the connection to the rods  28  (See  FIG. 4 ). 
         [0028]    The linear actuators  24  may be screw-type electric linear actuators. According to a preferred embodiment, the linear actuators  24  have in input voltage of 12V DC such that they can be powered by a standard vehicle battery when the trailer  10  is attached to a towing vehicle. A wire harness  40  may be attached to each linear actuator  24  to connect with the electrical system of the towing vehicle, or other electrical power source. According to a preferred embodiment, the linear actuators  24  may include a  12 A motor and have a sixty (60) inch stroke. A linear actuator sold under the brand/model Progressive Automations PA-04 has been found to be suitable. The linear actuators  24  are preferably controllable with a remote control, such as an RF or Bluetooth controller. The linear actuators  24  may be provided with a smart controller that permits actuation through a mobile device application. The linear actuators  24  may include limit switches to stop the rods  28  in the fully open and fully closed positions. Alternatively, a user may stop the linear actuators  24  with the door in any desired position from fully opened to fully closed, or anywhere in between, using the remote controller, or other activator. Additionally, the controller may be programmable to stop the door  34  at pre-programmed or learned intermediate positions. As a still further option, the controller may be programmed to open the door  34  to a desired position and automatically move it back to a closed position after a set period of time to facilitate unloading a desired amount of material through the hopper. 
         [0029]    The opening and closing apparatus  16  will operate without the need to disconnect the existing rack and pinion manual opening and closing systems  42  (see  FIG. 9 ) on most trailers. However, in case the opening and closing apparatus  16  is not functioning, or there is no available electrical source, the rods  28  may be quickly and easily detached from the bracket  30 , so that the actuator  24  does not preclude or prevent manual movement of the door  34 . 
         [0030]      FIGS. 7-10  show an alternative embodiment of the opening and closing apparatus  16  that also includes a motor guard  44 . The motor guard  44  may be formed of any appropriate material, such as from metal plates that are welded together, to form a shield that protects the motor  26 , especially during times when the trailer  10  is being transported. As best seen in  FIG. 7 , the guard  44  may include a lower plate  46  that is bolted or otherwise secured to the rail  22  below the motor  26 , and a cover  48  that is welded to the plate  46  to protect the motor  26 , especially against contact that might occur during movement of the trailer  10 , and from weather and debris. 
         [0031]    The opening and closing apparatus  16  improves upon existing hydraulic door options. The linear actuators  24  are smaller, simpler to install, and permits more accurate control of the door position. Unlike a hydraulic system, the linear actuators  24  do not require power input to hold their position. The actuators are also quieter and better for the environment. 
         [0032]    The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.