Patent Publication Number: US-6669172-B1

Title: Post puller

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 60/359,941, filed Feb. 27, 2002. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a post puller for use with a front end loader. 
     The conventional manner for pulling fence posts employs a front end loader having a bucket with a chain suitably attached thereto. The front end loader is typically operated in conjunction with a tractor. The operator of the tractor first moves the bucket into a position adjacent to the post to be pulled. The operator, if working alone, must then dismount from the tractor and secure the chain to the post. The operator then remounts the tractor and raises the bucket to pull the post from the ground. After lowering the bucket to place the post on the ground, the operator again dismounts from the tractor to remove the chain from the post. 
     The above-described series of actions are repeated for each post being pulled. This is obviously labor intensive and time consuming. Several post pulling devices have been developed for use with a front end loader or three-point hitch of a tractor. Such devices provide some improvement insofar as reducing the required time and labor, but are either too complex or prohibitively expensive to produce. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a post puller useable with a front end loader which is simple and inexpensive in construction. 
     The above object is realized by a post puller for use with a front end loader having a bucket, comprising: a pipe having a longitudinal axis, opposing ends, an interior surface, and an exterior surface; a first tooth member integrally connected to the interior surface of the pipe at one end thereof, the first tooth member having opposing, circumferentially spaced first ends and an inner edge extending between such first ends so as to arch outwardly from the longitudinal axis of the pipe; a second tooth member integrally connected to the interior surface of the pipe at the other end thereof and transversely opposite the first tooth member, the second tooth member having opposing, circumferentially spaced second ends and an inner edge extending between such second ends so as to arch outwardly from the longitudinal axis of the pipe; a mounting member integrally connected to the exterior surface of the pipe; and connection means for fixedly but removably connecting the mounting member to the bucket to thereby fixedly mount the pipe to the bucket. Two embodiments are hereafter described which use different connection means. 
     According to another aspect of the invention, there is provided an apparatus comprising: a loader bucket; a pipe fixedly mounted to a side wall of the bucket; and a pair of tooth members integrally connected to the pipe and configured in the manner described above. 
     In use, the bucket of a front end loader is positioned to place the pipe over a post to be pulled, and the bucket is pivoted to tilt the pipe so that the tooth members engage the post. The bucket and associated pipe are raised to pull the post from the ground. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of one embodiment in which the above-mentioned mounting member, as integrally connected to the pipe, has bolts extending therefrom. 
     FIG. 2 is a top view of the embodiment of FIG. 1 with the mounting member fixedly but removably connected to the side wall of a bucket with nuts threadedly received on the above-mentioned bolts. 
     FIG. 3 is a side view of the pipe fixedly mounted to the bucket of a front end loader in use for pulling a post from the ground. 
     FIG. 4 is a perspective view of another embodiment showing the mounting member with a plate integrally connected thereto. 
     FIG. 5 is a perspective view of a receptacle frame as integrally connected to the side wall of a bucket. 
     FIG. 6 is a top view of the embodiment of FIG. 4 with the mounting member fixedly but removably connected to the side wall of the bucket by means of the plate as received by the receptacle frame and an associated fastener pin. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In the following description and throughout this application, where a component of the post puller is described as being “integrally connected” to another component, this means that such components are fixedly connected to one another (i.e. by welding) or integral with one another. In addition, one component “fixedly connected” or “fixedly mounted” to another component is immobile with respect to such other component. 
     Referring to FIG. 1, the illustrated embodiment includes a pipe  10  having a longitudinal axis  12 . Pipe  10  is shown as having a circular shape, but other shapes are within the scope of the invention. Pipe  10  preferably has an inside diameter large enough (i.e. 8-10 inches) to accommodate most posts, and a wall thickness (i.e. about ⅜ inch) sufficient to withstand the considerable stress encountered during use. It is also preferred that pipe  10  is somewhat elongated. For example, a pipe having an inside diameter of 10 inches could have a length of 12 inches. 
     A first tooth member  14  is integrally connected to the interior surface of pipe  10  at the upper end thereof. Tooth member  14  has opposing, circumferentially spaced ends and an inner edge extending between such ends so as to arch outwardly from axis  12 . A second tooth member  16  (indicated by broken lines) is integrally connected to the interior surface of pipe  10  at the lower end thereof and transversely opposite tooth member  14  so as to be on the opposite side of the pipe. Like tooth member  14 , tooth member  16  also has opposing, circumferentially spaced ends and an inner edge extending between such ends so as to arch outwardly from axis  12 . 
     In the illustrated embodiment, the inner edge of each tooth member defines a circular arc conforming to the shape of pipe  10 . However, such inner edge could have some other shape which arches outwardly from axis  12 , such as a “v” shape. The illustrated embodiment employs suitably curved triangle bar stock to form each of tooth members  14  and  16 . Each triangle bar is preferably positioned to have its upper face substantially perpendicular to axis  12  in order to optimally grip a post. A suitable width for such upper face is about ¾ inch. Assuming a pipe inside diameter of 10 inches, each tooth member can have a suitable circumferentially measured length of about 8 inches. 
     A mounting member  18  is integrally connected to the exterior surface of pipe  10  so as to longitudinally extend between its upper and lower ends in intermediate relation to transversely opposed tooth members  14  and  16 . Mounting member  18  is preferably comprised of channel; that is, a bar of U-shaped cross section. A suitable width for mounting member  18  is about 4 inches, and its wall thickness can be about the same as that of pipe  10 . In the illustrated embodiment, a pair of longitudinally spaced bolts  20  are integrally connected to mounting member  18  so as to transversely extend therefrom. 
     Referring to FIG. 2, this top view shows each of tooth members  14  and  16 , as well as the head of the upper bolt  20  as integrally connected to mounting member  18 . The lower bolt  20  is not visible in FIG.  2 . Predrilled holes are provided in side wall  22  of a bucket, which is shown in its entirety in FIG.  3 . Such holes are adapted to receive respective bolts  20  therethrough. A plate  24 , having corresponding holes, is positioned on the side of side wall  22  opposite mounting member  18 . The threaded shaft of each bolt  20  extends through aligned holes in side wall  22  and plate  24 . Such aligned holes are indicated by broken lines. A nut  26  is threadedly received upon each bolt  20  and is tightened against a washer  28  to fixedly but removably connect mounting member  18  to side wall  22 , thereby fixedly mounting pipe  10  to such side wall of the bucket. 
     Referring to FIG. 3, this FIGURE shows a portion of a front end loader having a bucket  30 . The front end loader can be operated in conjunction with a tractor (not shown). Bucket  30  has the above-mentioned side wall  22 , as well as a back wall  32  and bottom wall  34 . An arm  36  is pivotally connected to back wall  32 , and hydraulic cylinder  38  is pivotally connected to back wall  32  above arm  36 . Of course, the front end loader has a pair of arms and a pair of hydraulic cylinders, but only one arm and one hydraulic cylinder is visible in the side view of FIG.  3 . 
     Pipe  10  is fixedly mounted to side wall  22  of bucket  30  in the manner described with reference to FIG.  2 . Pipe  10  is preferably mounted to side wall  22  adjacent to back wall  32  for optimum visibility to the operator, and adjacent to bottom wall  34  for ease of use. Bottom wall  34  is substantially planar in the illustrated embodiment so as to define and lie in a plane. For reasons discussed further below, pipe  10  is also angularly oriented on bucket  30  so that the upper end of pipe  10  is positioned farther back on the bucket than the lower end. Most preferably, longitudinal axis  12  of pipe  10  defines an acute angle α of about 20-300° with respect to a line perpendicular to the plane of bottom wall  34 . 
     FIG. 3 shows bucket  30  as having already been positioned to place pipe  10  over a wooden post  40  and appropriately pivoted by hydraulic cylinder  38  to tilt pipe  10  with respect to vertical, such that tooth members  14  and  16  (FIG. 2) engage and grip the post. The operator then raises bucket  30  and associated pipe  10  upward as indicated by the arrow to pull post  40  from the ground. If post  40  does not fall immediately out of pipe  10  to the ground, pivoting bucket  30  to position pipe  10  in a more vertical orientation assists in releasing the post from engagement with the tooth members. The operator can then move on to the next post for pulling in the same manner as described above. The operator can pull any number of posts in accordance with the invention using only the controls of the front end loader and without any need to dismount from the tractor. The time and labor required to pull the posts is consequently minimized. 
     Posts smaller than that shown require more tilt of pipe  10  with respect to vertical in order for the tooth members to engage the post, which means that hydraulic cylinder  38  must pivotally pull the bucket back to a greater extent. The angular orientation of pipe  10  on bucket  30  as discussed above allows the necessary tilt to be achieved while staying within the operational limits of the hydraulic cylinder in regard to backward pivotal movement. 
     To pull a steel post (not shown) having longitudinally spaced knobs, pipe  10  is tilted until both tooth members engage the post with at least one tooth member engaging the lower surface of a knob, such that upward movement of bucket  30  pulls the steel post from the ground. 
     Referring to FIG. 4, the illustrated alternative embodiment is similar to the previously described embodiment in having a pipe  42 , tooth members  44  and  46 , and mounting member  48 . However, in FIG. 4 a plate  50  is integrally connected to mounting member  48 . Plate  50  extends along the length of mounting member  48  from a lower end to an upper end spaced slightly above the upper ends of pipe  42  and mounting member  48 . As shown, a hole  52  is provided in plate  50  adjacent to its upper end. Plate  50  is somewhat wider than mounting member  48 , such that the opposing sides of plate  50  overlap corresponding sides of mounting member  48 . Assuming mounting member  48  is 4 inches wide, a suitable width for plate  50  is about 6 inches. The thickness of plate  50  can be about the same as the wall of pipe  42  (i.e. about ⅜ inch). 
     Referring to FIG. 5, the illustrated receptacle frame  54  includes a plate  56  integrally connected (preferably welded) to side wall  58  of a bucket. Plate  56  has a hole  60  adjacent to its upper end. A bar  62  is integrally connected to and extends across the lower end of plate  56 . Bars  64  and  66  are integrally connected to and extend along opposing sides of plate  56 . Accordingly, bars  62 ,  64 , and  66  form a “U” shape. Bars  68  and  70  are integrally connected to and extend along respective bars  64  and  66  down to bar  62 , but are slightly wider (i.e. by about ½ inch) than bars  64  and  66  to thereby form transversely opposing slots  72  and  74 . Receptacle frame  54  is adapted to receive plate  50  (FIG. 4) in slots  72  and  74  so that holes  52  (FIG. 4) and  60  are aligned. Bar  62  acts as a stop to plate  50 . Plate  56  and bars  62 ,  64 ,  66 ,  68 , and  70  have respective widths and lengths suitable to receive plate  50  in slots  72  and  74 . The thickness of plate  56 , bar  68 , and bar  70  can be about the same as plate  50 , whereas the thickness of bars  62 ,  64  and  66  should be greater than that of plate  50 . Consequently, slots  72  and  74  have a depth slightly greater than the thickness of plate  50 , such that plate  50  can be easily and smoothly received in the slots. For example, if plate  50  has a thickness of about ⅜ inch, each of bars  62 ,  64 , and  66  can have a thickness of about ½ inch. 
     Referring to FIG. 6, this top view shows plate  50  as received in the above-mentioned slots of receptacle frame  54 . The upper ends of plate  56  and bars  62 ,  64 ,  66 ,  68 , and  70  are shown in FIG. 6. A fastener pin  76  is received through hole  52  (FIG.  4 ), hole  60  (FIG.  5 ), and a predrilled hole in side wall  58 . Such holes, as aligned with one another, are indicated in FIG. 6 by broken lines. Fastener pin  76  has several transversely extending holes adjacent to its end. A keeper pin  78  (of which only the upper end is visible) is received through one of such holes immediately adjacent to a washer  80 . It should be apparent that this embodiment provides an alternative and quick means of fixedly mounting the pipe to the side wall of a bucket. 
     With respect to materials of construction, all components are preferably composed of steel for optimum strength and durability. 
     Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention can be practiced otherwise than as specifically described.