Abstract:
A tie down device for securing equipment such as lawn mowers, snow blowers, and generators to the deck of a trailer comprises a retractable arm which hangs under the trailer deck when not in use but which may be extended above the deck in order latch onto a mating projection on the equipment to be secured.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a tie down device to secure items to a deck. More particularly, it relates to a device which will secure equipment such as lawn mowers, garden tractors, snow blowers, and construction equipment to a trailer deck to secure such equipment for transport. 
     Landscape contractors, builders, snow removal contractors, and even home owners have a need to transport equipment to and from a job site. This transport of equipment is generally accomplished using a trailer, and it is preferred to secure the equipment to the trailer so it will not move around or fall off during transit. There is a need for a simple mechanism to safely and quickly secure the equipment to the trailer. Preferably, this mechanism should be inexpensive, easy to install, and easy to use. It should not be in the way when loading or unloading the equipment onto the trailer, and it should also offer the possibility of not only tying down but also of locking down the equipment to the trailer so that the equipment may not be readily stolen. 
     SUMMARY OF THE INVENTION 
     The present invention provides a tie down device to secure equipment to a trailer deck. A preferred embodiment of the present invention has two main parts—a retractable tie down arm, which is secured to the trailer deck, and an equipment connector, which is secured to the equipment to be tied down (by welding, bolting, riveting, or some other suitable means). In the preferred embodiment, the tie down arm has a receiving nose with an opening that is sized to receive a projection from the equipment connector. 
     To secure the equipment to the trailer, the equipment is placed on the trailer so that the equipment connector is next to the tie down arm (which at this point is still mostly retracted under the trailer deck). The tie down arm is then pulled up, and the opening on the nose of the arm is slid over a projection on the equipment connector. A locking pin is inserted through a hole in the projection to fasten the projection and arm together. The locking pin may be replaced by a padlock or other lock in order to lock down the equipment to the trailer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a trailer on which is secured a lawn mower using a tie down device made in accordance with the present invention; 
     FIG. 2 is an enlarged view of the tie down device of FIG. 1; 
     FIG. 3 is the same view as FIG. 2, except that the tie down arm has been released from the equipment connector, and the arm is retracted to be almost flush with the trailer deck; 
     FIG. 4 is a broken away side view, partially in section, of the tie down arm in the retracted position, almost flush with the trailer deck as shown in FIG. 3; 
     FIG. 5 is the same view as FIG. 4, except that the tie down arm is in the fully extended position as shown in FIG. 2; 
     FIG. 6 is a view along line  6 — 6  of FIG. 5; and, 
     FIG. 7 is a view along line  7 — 7  of FIG.  5 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIGS. 1-7 show a preferred embodiment of a tie down device  10  made in accordance with the present invention. This preferred embodiment includes nine pieces: an equipment connector  12 , a locking pin  14 , a tie down arm  16 , an upper mounting plate  18 , a lower mounting plate  20 , and two carriage bolts  22  with corresponding nuts  24 . 
     In this preferred embodiment, the equipment connector  12  is made up of a flat, rectangular piece of steel  30  (See FIG. 3) onto which is welded a horizontally-oriented cylindrical projection  32  sized to be received in a circular opening  46  in the nose  44  of the tie down arm  16 , as will be explained later. The projection  32  has a vertical opening  34  which extends through the projection  32  and receives a locking pin  14 . The locking pin  14  in this preferred embodiment includes a pivot ring  15 , which is swivelled down around the projection  32  to secure the locking pin  14  to the projection  32 . The tie down plate  30  is secured to the equipment  36  to be tied down to the trailer  38  by any suitable means such as by bolting, welding, or riveting, and is secured to the equipment  36  at a height which will allow the tie down arm  16  to engage the projection  32  when the tie down arm  16  is fully extended, as will be explained in further detail later. 
     The tie down arm  16  includes a shaft  40  having first and second ends  40 A and  40 B. A flange  42  is secured to said first end  40 A, and the maximum diameter of the flange  42  is larger than the diameter of the shaft  40  and larger than the opening  48  in the lower mounting plate  20 , as will be explained later. A flat, nose-like projection  44  is secured to said second end  40 B, and this projection  44  has an opening  46  with a inside diameter which is larger than the diameter of the horizontally-oriented cylindrical projection  32  on the equipment connector  12 , so that the opening  46  can easily slide over the cylindrical projection  32 . The nose-like projection  44  of the tie-down arm  16  is flat but is wider than the cylinder  40  to which it is secured, and it defines two shoulders  50  projecting outwardly from the cylinder  40 . 
     The lower mounting plate  20  (See FIGS. 4,  5 , and  7 ) preferably is a flat, rectangular piece of steel which has a circular central opening  48  and two square side openings  52 . The central opening  48  has a diameter larger than the diameter of the shaft  40  of the tie down arm, smaller than the diameter of the flange  42  which is secured to the first end  40 A of the tie down arm  16 , and smaller than the maximum width of the nose portion  44  of the tie-down arm  16 . Since the two ends of the tie-down arm  16  are larger than the diameter of the central opening  48  in the lower mounting plate, the tie-down arm  16  and lower mounting plate  20  cannot be separated from each other except by cutting or deforming one of the members. 
     The upper mounting plate  18  (See FIGS. 4-6) preferably is a flat, rectangular piece of steel, identical to the lower mounting plate  20 , except that the central opening  56  of the upper plate  18 , which corresponds to the central opening  48  in the lower mounting plate  20 , defines an additional rectangular slot or keyway  58 , sized to receive the shoulders  50  of the flat, nose-like projection  44 . When the nose  44  of the tie-down arm  16  drops down through the slot  58 , it falls until the shoulders  50  abut the lower mounting plate  20 . At this point, only the uppermost portion of the nose projection  44  projects up through the upper mounting plate  18 . (See FIG. 4.) Thus, in this preferred embodiment, the nose portion  44  has a height that is slightly greater than the combined thickness of the deck and the upper mounting plate  18  in order that the nose projection  44  will project slightly above the upper mounting plate  18  when it is retracted. Most decks are made of 2×4-inch lumber, so the height of the nose projection  44  in this preferred embodiment is about 2-¼ to 2-½ inches. If the deck is thinner, then spacers can be provided to mount between the bottom surface of the deck and the lower mounting plate  20 . These spacers may be identical to the upper mounting plate  18 , or they may just be a stack of washers mounted over the carriage bolts. 
     When the mounting arrangement is being constructed, the shaft  40  of the tie-down arm  16  is inserted through the opening  48  in the lower mounting plate  20  before the last of the flange  42  and nose  44  is welded onto the shaft  40 , so the lower mounting plate  20  is trapped onto the tie down arm  16 . (While the flange and nose preferably are welded onto the shaft  40 , they may also be bolted on or secured by other known means.) The mounting parts usually would be supplied to the customer as a kit, which the customer would then use to install the mounting arrangement on a deck, so the customer would receive a kit including the tie-down arm  16  with the lower mounting plate  20  trapped onto the arm  16 , and then loose parts including the upper mounting plate  18 , the carriage bolts  22  and nuts  24 , the equipment connector  12 , and the locking pin  14 . 
     The customer would then assemble the mounting arrangement onto his deck. First, a central hole  55  is drilled through the deck  38  to a diameter that is at least as large as the width of the nose  44 . Next, two side holes are drilled through the deck to receive the carriage bolts  22 . Then, the nose  44  of the tie-down arm is inserted from beneath the deck through the central hole  55  in the deck, the upper mounting plate  18  is placed on top of the deck and aligned with the drilled holes, and the upper and lower mounting plates  18 ,  20  are fastened together, with the deck sandwiched between them, by means of the carriage bolts  22 , which extend through the holes  54  in the upper plate  18 , through holes in the deck, and through holes  52  in the lower plate  20 , and are secured with nuts  24 . The central holes  56  and  48  of the upper and lower mounting plates  18 ,  20  and the side holes  54 ,  52  are aligned. 
     The installed tie down arm  16  is then free to move upwardly until the lower flange  42  of the tie-down arm  16  hits against the bottom surface of the mounting plate  20 . Also, the tie down arm  16  is free to move downwardly until the shoulders  50  hit against the top of the lower mounting plate  20 . Thus, the lower mounting plate  20  acts as a stop to control how far up and down the tie down arm  16  may move. (See FIG. 5 for the extended position and FIG. 4 for the retracted position.) 
     Then, the equipment  36  is loaded onto the deck  38  and placed in its intended location. The tie down arm  16  is lifted up, the projection  32  on the equipment is inserted through the opening  46  on the nose-like projection  44  of the tie down arm  16 , and the flat steel plate  30  of the equipment connector  12  is then bolted or otherwise secured to the equipment  36 . 
     Once the tie down device  10  has been installed, it is quick, easy, and safe to use. To secure the equipment  36  to the trailer  38 , the operator loads the equipment  36  to the designated location on the trailer, and lifts up the tie down arm  16 . The operator then slides the opening  46  of the nose-like projection  44  of the tie-down arm  16  over the cylindrical projection  32  secured to the equipment  36 . Then, the operator secures the tie down arm  16  to the tie down projection  12  by means of the locking pin  14 . The operator may alternatively choose to insert a padlock (not shown) in place of the locking pin  14  in order to help prevent theft of the equipment  36 . To remove the equipment  36  from the trailer  38 , the operator simply reverses the aforementioned steps. 
     The central holes  56 ,  48  in the upper and lower mounting plates  18 ,  20  are slightly oversized relative to the diameter of the shaft  40 . This gives the device  10  enough play to make it easy to mount the equipment  36 . However, there is enough rigidity to the device  10  that it secures the equipment on the deck and prevents the equipment from rolling around on the trailer deck as the trailer is pulled down the road. Of course, while this device  10  is shown being used on a trailer deck, it may be used on other decks as well. 
     This tie down device  10  greatly speeds up and simplifies the tie down and removal of equipment from a trailer, and, by automatically retracting, this tie down device  10  limits the opportunity for the operator to trip over it when walking around on the deck. 
     While this preferred embodiment has a projection secured to the equipment which fits through an opening in the tie down arm, it would also be possible in an alternative embodiment to have an opening on the equipment connector and the projection on the tie down arm, with the tie down arm projection extending through the opening on the equipment connector. 
     It will be obvious to those skilled in the art that other modifications may be made to the embodiment described above without departing from the scope of the present invention.