Abstract:
The invention of this application is a protective sleeve for posts, such as fence posts, which are placed in the ground and cemented in place. The use of the protective sleeve increases the useful life of the post and makes it easy to replace a broken post without removing the concrete.

Description:
[0001]    This application claims the benefit of my Provisional Application No. 60/440,157 dated Jan. 14, 2003, which is hereby incorporated by reference herein. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    1. Field of the Invention  
           [0003]    The invention pertains to erecting fence posts, more particularly to sleeves which are placed in the ground to accept fence posts.  
           [0004]    2. Description of the Prior Art  
           [0005]    The prior art for fence building involves erecting a fence supported by fence posts. The fence posts are placed in holes in the ground. The holes are filled around the pole, generally by filling the hole with concrete for structural support. The problem with the prior art is that the poles are attacked by rot in the wet environment of the ground. When a fence post fails and needs to be replaced, it is necessary to break away the concrete, replace the post, and replace the concrete. This is a costly and inefficient proposition. It would be desirable to extend the life of the posts and/or provide a means for replacing the post without breaking up the concrete base.  
           [0006]    Several devices have been suggested for implanting tubes, sleeves, or boots into the ground to protect a post and extend its life. U.S. Pat. No. 5,315,796 to Gruhlke discloses an encapsulating sleeve for underground portion of the posts providing a positive barrier against deterioration by ground contact. The sleeve has an open top to receive a post, sides and a closed bottom. The sleeve is designed for a snug fit with the post and side vents for escape of air when the post is inserted into the sleeve. U.S. Pat. No. 5,090,165 to Kenny discloses a sleeve or boot designed to encase a preformed base configured diametrically smaller than the remainder of the post or pole. U.S. Pat. No. 6,389,760 to McDonnell is another wood post protective sleeve which has an open top and a closed bottom and displacement resisting projections extending from the external surface of the sleeve to resist compressive forces which would tend to lift the post out of the sleeve.  
           [0007]    U.S. Pat. No. 5,492,429 to Hodges is a device for erecting a post which comprises a tubular body with a deformable, removable internal collar for tightly retaining a post in place. Hodges&#39; device holds a post in place and allows replacement of the post without removing the device from the concrete.  
           [0008]    U.S. Pat. No. 5,315,796, U.S. Pat. No. 5,090,165, U.S. Pat. No. 6,389,760, and U.S. Pat. No. 5,492,429 are hereby incorporated by reference herein.  
           [0009]    There is a need for an improved protective sleeve for posts imbedded in concrete that increases the life of a post and also allows easy replacement of a broken post without removal of the concrete.  
           [0010]    There is a need for an improved protective sleeve for posts imbedded in concrete that increases the life of a post and also allows easy replacement of a broken post without removal of the concrete, wherein said improved protective sleeve is inexpensive and easy to use.  
           [0011]    There is a need for an improved protective sleeve for posts imbedded in concrete that increases the life of a post and can be used to make removable fence sections.  
         SUMMARY OF THE INVENTION  
         [0012]    It is an object of the invention to provide an improved protective sleeve for posts to be placed in concrete that increases the life of the post and allows a broken post to be easily removed.  
           [0013]    It is a further object of the invention to provide an improved protective sleeve for posts to be placed in concrete that increases the life of the post and allows a broken post to be easily removed, wherein the improved protective sleeve is inexpensive and easy to use compared to the prior art.  
           [0014]    It is a further objective of the invention to provide a method of using a protective sleeve to increase the life of a post and replace the post without removing concrete used to anchor the post.  
           [0015]    It is a further objective of the invention to provide a method for making a fence with a removable section using protective sleeves.  
           [0016]    One aspect of the invention is a protective sleeve for use in placing a post in the ground secured with concrete. A typical use is placing a fence post in the ground such as a wooden post or a metal post. Another use is support poles for structures. These examples are not limiting, and other uses will be obvious to those skilled in the art.  
           [0017]    A protective sleeve for a post, the post having a cross sectional shape comprises:  
           [0018]    (a) an elongate body with a cross sectional shape similar to the shape of the cross sectional shape of the post, the elongate body having two substantially open ends, an outer surface and an inner surface, and  
           [0019]    (b) a plurality of axial protrusions emanating into the elongate body from said inner surface, such that said protective sleeve is capable of accepting the post within the elongate body inside of the axial protrusions.  
           [0020]    Preferably the sleeve is designed such that the post fits comfortably within the inner volume defined by the protrusions, within a preferred tolerance. Tolerances preferably range from about {fraction (1/64)} inch to about {fraction (1/16)} inch, preferably about {fraction (1/32)} inch. The sleeve preferably has a height that is sufficient for the sleeve to cover the portion of the post that will be in the ground and in addition to extending above the ground.  
           [0021]    Preferred protrusions include ripples with a triangular shape when viewed in a cross section drawn perpendicular to the height of the elongate body. Other shapes are “T” shaped protrusions or rectangular shaped channels.  
           [0022]    A preferred sleeve is made with the elongate body and protrusions being part of a single integral structure made by extrusion through at least one die. A preferred material is a soft and durable plastic, preferably polyvinyl chloride.  
           [0023]    The sleeve is held in place with preferably at least one screw and more preferably at least two screws that are screwed through the sleeve and into the post. The screws are preferably placed in the section of the sleeve which is above ground level, preferably about four inches down from the top of the sleeve.  
           [0024]    Another aspect of the invention is a method for using the protective sleeves as described above, comprising the acts of:  
           [0025]    a) providing a hole in the ground;  
           [0026]    b) placing an end of a post in a protective sleeve,  
           [0027]    c) placing at least one and preferably two screws through the protective sleeve into the post;  
           [0028]    d) placing the protective sleeve into the ground, and  
           [0029]    e) filling the hole around the protective sleeve, preferably with concrete.  
           [0030]    It is preferred to put gravel into the bottom of the hole before placing the protective sleeve and post into the hole. This provides for improved drainage of water and also makes it possible to adjust the vertical position of a post after it is set by removing the screws, pulling out the post and adding more gravel to the sleeve. The order of the above steps is not critical. For instance, a post may be placed in a sleeve and the at least two screws put in place before placing the post and sleeve into the ground. Alternatively, the sleeve may be placed in the hole and concreted in with a portion of the sleeve extending above ground level. The pole is then placed in the sleeve, pushed into place, and the screws applied.  
           [0031]    Still another aspect of the invention is using protective sleeves for making a removable fence section. In this aspect the protective sleeves have a shape and size to accept two fence posts side by side within the sleeve. The method comprises the following acts:  
           [0032]    a) providing three fence sections, the removable fence section and two adjacent fence sections, each fence section being between two fence posts,  
           [0033]    b) providing two holes in the ground each hole being located to accept one fence post from the removable fence section and one fence post from one of the adjacent fence sections,  
           [0034]    c) placing a protective sleeve in each of the two holes, filling the holes around each the two protective sleeves;  
           [0035]    d) placing a pair of fence posts in each of the two protective sleeves, wherein each pair of fence posts consists of one fence post from the removable fence section and one fence post from one of the adjacent fence posts in each of the protective sleeves;  
           [0036]    e) placing at least one shim between each pair of fence posts in a protective sleeve; and  
           [0037]    f) placing at least one and preferably two screws into each fence post in a protective sleeve, whereby the removable section may be removed by removing the at least two screws though each of its fence posts and removing each of the at least one shims adjacent to each of its fence posts.  
           [0038]    The invention provides a number of advantages compared to the prior art, as follows:  
           [0039]    1. The invention provides a post sleeve that provides extended life for the fence post and allows ready removal of the fence post in the same device.  
           [0040]    2. The open bottom of the sleeve is a departure from the prior art. Instead of trying to encase the post in an impervious encasement as in the prior art, the instant invention allows water to drain out through the open bottom. Drainage is promoted by a gravel layer at the bottom of the hole.  
           [0041]    3. The axial protrusions of the invention provide protection to the post without extensive contact with the walls of the sleeve. When water inevitably moves into the post, snug contact with the walls promotes mold growth and deterioration of the post. In the instant invention sleeves, there is minimal contact due to the protrusions and plenty of space for air circulation during dry weather conditions to allow the post to dry out.  
           [0042]    4. The open bottom allows gravel to be added or removed to adjust the height of a post after the cement has been set.  
           [0043]    5. The only attachment points between the sleeves and a post within, are at least one and preferably two screws located above ground level. This allows for easy removal of a post by simply removing the screws. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0044]    These and other features, aspects and advantages of the present invention will become better understood with regard to the following description, appended claims and accompanying drawings, where:  
         [0045]    [0045]FIG. 1A is a top view of the protective shield. FIG. 1B is a front view of a protective shield.  
         [0046]    [0046]FIG. 2 is a front view of a group of three fence posts deployed in the ground with protective sleeves.  
         [0047]    [0047]FIG. 3 is a front view of a removable fence section according to the invention.  
         [0048]    [0048]FIG. 4 is a top view of a protective shield with “T” shaped protrusions.  
         [0049]    [0049]FIG. 5 is a top view of a circular protective shield. 
     
    
     DESCRIPTION  
       [0050]    The invention involves a protective sleeve for use in installation of posts into the ground, generally posts that are placed in a post hole and secured by concrete which fills the post hole. One preferred embodiment of the invention is a protective shield comprising an elongate body having a cross sectional shape similar to the shape of a post, having two substantially open ends, an inner surface and an outer surface. The elongate body has a plurality of axial protrusions emanating into the elongate body from the inner surface.  
         [0051]    The cross sectional shape of the elongate body is said to be similar to the post in that it has generally the same shape as the post. Thus the elongate body for a circular cross sectioned post will be generally circular and that for a rectangular cross sectioned post will be generally rectangular with similar ratio of length to width as the cross section of the post. In this context, cross sectional refers to the cross section that is perpendicular to the height of the elongate body. The cross sectional shape of the elongate body is sufficiently larger than that of the post so that the post will fit comfortably into the protective shield. It is not necessary that the similarity be precise geometrical similarity, for instance, the protective sleeve for a rectangular post may have rounded corners.  
         [0052]    When the sleeve is described as elongate, the term is used to describe an object that has a height that is larger than its diameter.  
         [0053]    The height of the protective sleeve is such that it will cover the portion of the post that will be placed in the ground and will extend above the ground.  
         [0054]    One preferred type of axial protrusion is a triangular cross section ridge extending from end to end of the elongate body, Another preferred type of protrusion is “T” shaped protrusion.  
         [0055]    Once the bottom of the post is in the sleeve, the post is held in place by driving at least one and preferably two screws through the sleeve into the post. The screws are preferably placed in the portion of the sleeve that will remain above ground when the post is in place. The screws may be located on one side of the sleeve or adjacent or opposing sides.  
         [0056]    One of the principles of the invention is to provide a protective sleeve that allows the post to dry out between wet cycles. Prior art sleeves have focused on keeping all water out of a sleeve by tightly encasing the post in a water impervious case. However, water will inevitably get into the underground portion of the post under wet conditions, at least by downward diffusion of water from the upper portion of the post that is not protected from rain. The instant design protects the post by minimizing contact with wet surfaces since the post is in contact only with the protrusions. Also, the open bottom promotes drainage from the bottom of the sleeve. A layer of gravel is preferably placed at the bottom of a hole to promote drainage.  
         [0057]    Another principle of the sleeve design is that replacement of a post should be easy to accomplish without removing the protective sleeve from the ground. One of the big advantages of the invention is that a protective sleeve allows a post to be replaced without removing concrete that is used to secure the post in the post hole. When a protective sleeve is used, a post within a protective sleeve is placed in a post hole and then the hole is filled with cement. If a pole rots or breaks off, the post can be replaced by simply removing the screws which hold the post to the sleeve and then removing the portion of the post remaining in the ground from the sleeve (discussed in greater detail below under section entitled “Method of Using a Protective Shield”) and inserting a new pole in the sleeve. This can be readily accomplished without removing the sleeve from the concrete. Without a sleeve it is necessary to break the concrete up and remove it to replace a post. The design features which accomplish this are the open bottom end of the sleeves, constructing the sleeve out of plastic, leaving a clearance between the post and the wall of the sleeve, and minimization of wall frictional contact by use of protrusions rather than a flat wall.  
         [0058]    [0058]FIG. 1 illustrates a first preferred embodiment of the invention. FIG. 1A is a top view and FIG. 1B is a front view. Referring to FIGS. 1A and 1B a protective sleeve  100  is shown with a post  106  therein. The sleeve has an elongate body  102  having an outer surface and an inner surface with axial protrusions  104  extending into the sleeve. The axial protrusions have a triangular shape in a horizontal cross section (perpendicular to the length of the sleeve) and extend from the top to the bottom of the sleeve. There is a tolerance  108  between the post and the inner surface of the protrusions. The post is held in the sleeve by screws  110 . The screws  110  may also be on opposing sides of the post. Note that in FIG. 1B the hidden lines corresponding to the axial protrusions on the front and back are not shown to prevent clutter.  
         [0059]    The sleeve shown is a protective sleeve for a square cross section wooden post such as a 4×4 post. A standard 4×4 post has an outside diameter of 3½ inches. This is the distance B on FIG. 1A. In one preferred embodiment of the invention the inside distance on a horizontal plane (perpendicular to the length of the sleeve) between opposing protrusions is about 3{fraction (9/16)} inches. This is the distance C on FIG. 1A. In this embodiment the tolerance between the post and the sleeve is {fraction (1/32)} inch or half of (C-B). In general for a 4×4 post the preferred tolerance is between a {fraction (1/64)}-inch and {fraction (1/16)}-inch and is larger for larger post sizes. In this preferred embodiment, the outside diameter of the protective sleeve is 3⅞ inches (distance A on FIG. 1A). The wall thickness (including the protrusions) is about {fraction (5/32)} inch with the protrusions being about {fraction (1/16)}-inch peak to valley. In this embodiment the axial protrusions are preferably spaced about {fraction (1/8)} inch tip to tip. In this preferred embodiment the body of the sleeve and the axial protrusions are a single integral piece of polyvinyl chloride which has been made by extrusion through a die. This method of construction is generally preferred and is well known to those skilled in the art. The polyvinyl chloride is preferably of the type that is treated for ultraviolet light resistance.  
         [0060]    In this preferred embodiment the height of the sleeve is 30 inches corresponding to about a buried depth of 24 inches and 6 inches extending above the soil line. The post is held in place by two #10×¼ inch stainless steel screws placed through the sleeve and into the post.  
         [0061]    Posts may be made with various shapes and sizes as well as various types of axial protrusions. FIG. 4 illustrates a square sleeve  400  with “T” shaped axial protrusions  401  with a post  402  therein. The post is held to the sleeve by screws  404 . A circular protective sleeve  501  for a circular post  502  is shown in FIG. 5. The protective sleeve has axial protrusions  504  having a triangular cross section. The post is held in the sleeve by screws  506 .  
         [0062]    Protective sleeves are preferably made to fit standard post sizes such as 4×4 in the previous example. It should be understood that the detailed dimensions will vary and the values given in the first preferred embodiment are for examples of one preferred embodiment and are not limiting.  
         [0063]    Larger diameter posts will be buried deeper into the ground and the height of a protective sleeve will be longer.  
         [0064]    Method of Using a Protective Shield  
         [0065]    The protective shield as previously described is used by taking the following acts:  
         [0066]    a) providing a hole in the ground,  
         [0067]    b) placing an end of a post in a protective sleeve,  
         [0068]    c) placing at least one screw and preferably two screws through the protective sleeve into the post;  
         [0069]    d) placing the protective sleeve into the ground, and  
         [0070]    e) filling the hole around the protective sleeve, preferably with concrete.  
         [0071]    It is important to note that there is not a particular order necessary for carrying out the acts. In one order, a protective sleeve is placed over an end of the post and the screws placed through the sleeve into the post before the sleeve (with included post) is placed in the hole. In a second order, the sleeve is placed in the hole first, then the hole is filled, and the post is then placed into the sleeve and the screws set.  
         [0072]    It is preferred that gravel is placed in the bottom of the hole before the sleeve and post are set. The gravel allows for improved water drainage. Preferably one inch to two inches of gravel are used. FIG. 2 shows three posts  200  concreted in the ground with post concrete  204 . A protective sleeve  202  has been placed over the portion of the post below ground level and extends above ground level where it is held on the post by screws  206  (a second screw is on the opposite side and is not shown). Gravel  205  has been placed under the posts. FIG. 2 illustrates one advantage of using protective shields. If a post needs to be raised after the posts are set in concrete, the post can be readily removed by removing the two screws and pulling the post out of the sleeve. The level can be raised by adding additional gravel into the sleeve and then returning the post to the sleeve and replacing the screws.  
         [0073]    Another advantage to using the protective sleeves is when a post that was installed with a protective sleeve needs to be replaced for any reason the use of a protective sleeve makes it possible to replace the post without digging up the whole or removing the concrete. For instance if a post breaks off due to rot, leaving a portion of the post in the sleeve, the post can be removed from the sleeve by removing the screws if necessary and pulling it out, A fragment of post left below ground level can be removed with a needle nose pliers.  
         [0074]    If it is desired to replace the protective sleeve as well as the post, once the post is removed the sleeve can often be pulled out of the concrete. If this can not be readily done, a sleeve can be removed by flling it with ice to shrink it and then pulling it out. A new sleeve and post can then be placed in the concrete.  
         [0075]    Removable Fence Section  
         [0076]    Another method of using a protective sleeve is in making a removable fence section. In this case the cross section of the protective shield is sized so that two posts will fit inside of it. The protective sleeve is otherwise the same as described above for a single post. The use of protective sleeves in this manner is illustrated on FIG. 3. The method comprises the following acts:  
         [0077]    a) providing three fence sections ( 306 , 308 , and  310 ), the removable fence section  306  and two adjacent fence sections  308  and  310 , each fence section being between two fence posts,  
         [0078]    b) providing two holes in the ground each hole being located to accept one fence post from the removable fence section and one fence post from one of the adjacent fence sections,  
         [0079]    c) placing a protective sleeve ( 300  and  302 ) in each of the two holes, filling the holes around each the two protective sleeves with concrete ( 310  and  304 );  
         [0080]    d) placing a pair of fence posts in each of the two protective sleeves, wherein each pair of fence posts consists of one fence post from the removable fence section ( 314  or  316 ) and one fence post from one of the adjacent fence posts in each of the protective sleeves ( 318  or  320 );  
         [0081]    e) placing at least one shim  304  between each pair of fence posts in a protective sleeve, the at least one shim held in place by screws ( 305 ); and  
         [0082]    f) placing at least one screw and preferably two screws ( 312 ) into each fence post in a protective sleeve, whereby the removable section may be removed by removing the at least one screw though each of its fence post and removing each of the at least one shims adjacent to each of its fence posts.  
         [0083]    Gravel  303  is preferably placed at the bottom of each hole beneath the post and protective sleeve. An example of a preferred set of components for a removable fence section comprises 2×4 pressure treated lumber for the fence posts  314 , 316 ,  318 , and  320 , and 1×4×⅜ inch redwood bender boards for shims  304  between each pair of fence posts. If these components are chosen then a preferred protective sleeve is the same sleeve that was previously described as being suitable for a single 4×4 fence post.  
         [0084]    Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore the spirit and scope of the appended claims should not be limited to the preferred versions herein.