Abstract:
An automated device for centering a mechanical tree spade provides a sighting device on each blade thereof with a readout adjacent to the operator to determine proper blade placement in order to provide an acceptable root ball for transplanting a tree.

Description:
This invention relates to an automated tree spade centering device, and more particularly, to an automated tree spade centering device, which includes a centering mechanism in order to assist the tree spade in the obtaining of a desirable root ball to thereby facilitate replanting of the tree. 
   BACKGROUND OF THE INVENTION 
   In the landscaping business, transplanting of larger trees is a popular method of achieving an aesthetically pleasing landscape appearance, without the necessity of planning smaller trees and waiting for them to grow. To that end, many devices are known to assist in such a project. 
   For example, a mechanical tree spade is commonly known in the prior art as used to remove such a large tree. The typical mechanical tree spade includes a housing with a number of blades mounted thereon. These blades form a very large circular spade, usually with about four blades, which can then be assembled around the trunk of a tree. The blades can then be driven into the ground and collapsed around the root ball of the tree. The tree can then be lifted out of the ground and transported to a desired position. 
   However, it is a major difficulty to center a mechanical tree spade around the root ball of a tree. Yet, by centering the mechanical tree spade around the root ball, the best root ball is achieved, so that replanting of the tree in a desired location provides the best chance for the tree to thrive in the new area. 
   One partially effective method, as shown in  FIG. 1 , for achieving desired center positioning of the mechanical tree spade  110  mounted on a truck  102  is having a control person  104  and a siting person  106  at the digging site, to assist in the positioning of the mechanical tree spade  110 . The cost of this additional siting person  116 , combined with the unsure accuracy provided thereby, brings the efficiency thereof into great question. It is very desirable to provide a more efficient manner of centering the mechanical tree spade around a tree decided to be transplanted. 
   It is further very useful to be able to modify an existing mechanical tree spade to have a centering device. Such an adaptable centering device provides a great cost savings if the centering device can be added to an existing mechanical tree spade, rather than having to replace the entire mechanical tree spade. 
   SUMMARY OF THE INVENTION 
   Among the many objectives of this invention is the provision of an automated device for centering a mechanical tree spade around a tree, which permits a root ball for the tree to be formed in an efficient fashion. 
   A further objective of this invention is the provision of an automated device for centering a mechanical tree spade, which reduces labor costs of transplanting a tree. 
   Yet a further objective of this invention is the provision of an automated device for centering a mechanical tree spade, which positions the mechanical tree spade around a tree efficiently. 
   A still further objective of this invention is the provision of an automated device for centering a mechanical tree spade, which is easily installed. 
   Another objective of this invention is the provision of an automated device for centering a mechanical tree spade, which improves the success rate for tree transplants. 
   Yet another objective of this invention is the provision of an automated device for centering a mechanical tree spade, which may be added to an existing mechanical tree spade. 
   These and other objectives of the invention (which other objectives become clear by consideration of the specification, claims and drawings as a whole) are met by providing an automated device for centering a mechanical tree spade in order to provide an acceptable root ball for transplanting a tree. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  depicts a prior art view of the use of a mechanical tree spade  110 . 
       FIG. 2  depicts a block diagram of the automated tree spade centering device  100  of this invention mounted on a mechanical tree spade  110 . 
       FIG. 3  depicts a perspective view of the automated tree spade centering device  100  of this invention mounted on a mechanical tree spade  110 . 
       FIG. 4  depicts a top plan view of four of blades on housing  112  for the mechanical tree spade  110 , each with a sighting device mounted on the blades. 
       FIG. 5  depicts a top plan view of five of blades on housing  112  for the mechanical tree spade  110 , each with a sighting device mounted on the blades. 
   

   Throughout the figures of the drawings, where the same part appears in more than one figure of the drawings, the same number is applied thereto. 
   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   With the automated tree spade centering device of this invention, a mechanical tree spade has a housing with a series of blades thereon. On each of the blades is a sighting device. Each sighting device reads the position of its respective blade relative to a desired point. 
   Also, the position of the sighting device is read relative to the other sighting devices. At least one of the sighting devices on each of two blades are desired. More preferred is a sighting device on each of three blades. Most preferred, is a sighting device on each of blade in the series of blades. 
   By coordinating the readings of all sighting devices, the desired position of the mechanical tree spade permits the blades thereof to be arranged so that the desired area the root ball is properly located. In this fashion, the blades can be coordinated to strike the ground and remove the desired root ball with the tree. 
   Customarily, the desired center point is based on the central vertical axis of the trunk of the tree sought to be transplanted. This device is used on a tree spade for digging a coniferous or deciduous tree. On each blade of the tree spade is positioned a sighting device, which concerns the position of each blade together with the orientation of the tree trunk in relation to the tree ball circumference. With the sighting device, it is quite possible to position the tree trunk in the center of the root ball in order to maintain a viable root zone more efficiently. 
   Referring now to  FIG. 2 , the automated tree spade centering device  100  is mounted on a mechanical tree spade  110 . The mechanical tree spade  110  has a housing  112  with a series of blades mounted thereon. Preferably, the blades are equally spaced around the housing  112  and include first blade  114 , second blade  116 , third blade  118  and fourth blade  120 . Optionally, other blade or blades may be attached to the housing  112  as desired. The four blade assembly is preferred. 
   Adding  FIG. 3  and  FIG. 4  to the consideration, automated tree spade centering device  100  includes at least first sighting device  140  mounted on first blade  114  and second sighting device  142  mounted on second blade  116 . Most preferred is the addition of third sighting device  144  mounted on third blade  118  and fourth sighting device  146  mounted on fourth blade  120  to first sighting device  140  mounted on first blade  114  and second sighting device  142 . 
   Each of the four sighting devices reads the position of each blade relative to the ground  122  and the tree trunk  124 . Each blade is then positioned so that the trunk  124  is at the center point of a circle formed by first blade  114 , second blade  116 , third blade  118  and fourth blade  120 . 
   Readouts from first sighting device  140 , second sighting device  142 , third sighting device  144  and fourth sighting device  146  are fed in a standard fashion to computer  160 . Computer  160  is programmed to take readouts and display the position of first blade  114 , second blade  116 , third blade  118  and fourth blade  120  around the trunk  124  of tree  126  and ground  128 . Once a desired center point is reached with the trunk  124  thereon, of first blade  114 , second blade  116 , third blade  118  and fourth blade  120  are cooperatively activated to remove the tree trunk  124  with an effective root ball  130 . 
   Computer  160  provides a screen readout  162  easily read by the operator (not shown). When the operator sees proper positioning of the blades on the screen  162 , the tree trunk  124  can be properly dug out of a current location and moved to a desired location. 
     FIG. 4  displays the use of four blades and  FIG. 5  displays the use of five blades. With the five blade system, in addition to first blade  114 , second blade  116 , third blade  118  and fourth blade  120 , fifth blade  170  is added with appropriate size adjustments being made in the other blades. Like the other blades, fifth blade  170  has a fifth sighting device  172 , which function in the same way as the similar devices. Such a structure illustrates the variation in the plurality of blades to be used. 
   This application—taken as a whole with the abstract, specification, claims, and drawings being combined—provides sufficient information for a person having ordinary skill in the art to practice the invention as disclosed and claimed herein. Any measures necessary to practice this invention are well within the skill of a person having ordinary skill in this art after that person has made a careful study of this disclosure. 
   Because of this disclosure and solely because of this disclosure, modification of this method and device can become clear to a person having ordinary skill in this particular art. Such modifications are clearly covered by this disclosure.