Patent Publication Number: US-11656069-B2

Title: Grading tools

Description:
RELATED APPLICATIONS/PRIORITY CLAIM 
     This application claims the benefit under 35 USC 119(e) to: U.S. Provisional Patent Application Ser. No. 63/105,611 filed on Oct. 26, 2020 and entitled “Grading Tool” which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND 
     Grading a surface of aggregate material, such as dirt, sand, gravel, or other material may be carried out to provide a smooth surface as a base for additional surfacing. For example, the aggregate material may be used as a base for paving asphalt or concrete. In other examples, the aggregate surface may be used as a base for paver stones in interlocking surfaces, such as for driveways, walkways or patios. Paver stones used to form an interlocking locking surface typically have a uniform depth such that when the paver stones are placed on the level aggregate material, the top surfaces of the paver stones form a flat surface. 
     The grading of the aggregate surface may be carried out using various pieces of machinery including heavy machinery having various grading and leveling tools. For smaller surfaces or for precision grading near edges, a hand grading tool may be used to manually grade and level the surface. The tool typically used to grade a surface includes a straight edge to effectively scrape the aggregate material to form a flat smooth surface. 
     SUMMARY 
     In accordance with an aspect of the invention, there is provided an apparatus. The apparatus includes an elongated member with a straight edge to grade a surface. In addition, the apparatus includes a height gauge to attach to an end of the elongated member. The height gauge is to engage a border of the surface, the border raised above the surface. Furthermore, the apparatus includes a connector to connect the height gauge to the elongated member. The apparatus also includes a first surface on the height gauge. The first surface is to engage a side wall of the border to grade the surface to the side wall. The apparatus further includes a second surface on the height gauge offset from the straight edge by a distance. The second surface is to engage a top surface of the border such that the straight edge is grade the surface at the distance below the top of the border. 
     The connector may include a connector opening in the elongated member and a portion of the height gauge configured to be received in the connector opening. 
     The of the height gauge configured to be received in the connector opening may be secured in the connector opening via a friction fit. 
     The apparatus may further include a securing mechanism. The securing mechanism may include a pin to engage a first hole aligned to a second hole. The first hole may be disposed on the elongated member and the second hole may be disposed on the height gauge. The pin may be disposed in the height gauge. The pin may extend through the second hole into the first hole. Furthermore, the pin may be biased toward an extended position. 
     The height gauge may be flush with the elongated member when connected. 
     The apparatus may further include a handle disposed on the elongated member to drag the elongated member across the surface. The handle may be a handle opening through the elongated member. 
     The apparatus may further include a top level disposed on a top surface of the elongated member. The apparatus may further include a front level disposed on a front surface of the elongated member. 
     In accordance with another aspect of the invention, there is provided a method. The method involves connecting a height gauge to an elongated member. The method further involves engaging a side wall of the raised border with a first surface of the height gauge. In addition, the method involves engaging a top surface of the raised border with a second surface of the height gauge. Also, the method involves grading the surface with a straight edge of the elongated member at a distance below the top surface of the raised border. The straight edge is offset from the second surface by the distance. 
     Connecting the height gauge to the elongated member may involve inserting a portion of the height gauge into a connector opening in the elongated member. 
     The method may further involve securing the height gauge to the elongated member. Securing may involve inserting the portion into the connector opening to cause a friction fit. 
     Securing may involve engaging a first hole aligned to a second hole with a pin. The first hole may be disposed on the elongated member and the second hole may be disposed on the height gauge. The pin may be disposed in the height gauge. The pin may extend through the second hole into the first hole. The pin may be biased toward an extended position. 
     Grading the surface may involve dragging the straight edge across the surface along the raised border. Dragging may involve pulling the elongated member with a handle. 
     The method may further involve monitoring a level disposed on the elongated member during grading. 
     In accordance with an aspect of the invention, there is provided an apparatus. The apparatus includes a body. The apparatus further includes a first surface on the body. The first surface is to engage a side wall of a border to grade a surface proximate to the side wall. The apparatus also includes a second surface on the body to gauge a distance above the surface. The second surface is to engage a top surface of the border. In addition, the apparatus includes a connection mechanism to connect the body to an elongated member. The elongated member includes a straight edge to grade the surface. The straight edge is offset from the second surface by the distance 
     The connection mechanism may include a portion of the height gauge configured to be received in a connector opening of the elongated member. 
     The apparatus may further include a securing mechanism to secure the body to the elongated member. The securing mechanism may be a friction fit. The securing mechanism may include a pin to engage a hole disposed on the elongated member. The pin may be biased toward an extended position to engage the hole. 
     The body may be flush with the straight edge of the elongated member when connected. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Reference will now be made, by way of example only, to the accompanying drawings in which: 
         FIG.  1    is a perspective view of an example of an apparatus to grade a surface along a border; 
         FIG.  2 A  is a perspective view of an example of a height gauge of the apparatus shown in  FIG.  1   ; 
         FIG.  2 B  is another perspective view of the example of the height gauge of the apparatus shown in  FIG.  1   ; 
         FIG.  3    is a flowchart of an example of a method of grading a surface along a border; 
         FIG.  4    is a perspective view of another example of an apparatus to grade a surface along a border; 
         FIG.  5 A  is a perspective view of an example of a height gauge of the apparatus shown in  FIG.  4   ; 
         FIG.  5 B  is another perspective view of the example of the height gauge of the apparatus shown in  FIG.  4   ; 
         FIG.  6 A  is a cross sectional view the example of the height gauge shown in  FIGS.  5 A and  5 B  along the plane  6 - 6  with a pin in the extended position; 
         FIG.  6 B  is a cross sectional view the example of the height gauge shown in  FIGS.  5 A and  5 B  along the plane  6 - 6  with a pin in the retracted position; 
         FIG.  7    is a perspective view of another example of an apparatus to grade a surface along a border; 
         FIG.  8    is a view of an example of a handle of the apparatus shown in  FIG.  7   ; 
         FIG.  9    is a view of an example of an end of the elongated member of the apparatus shown in  FIG.  7   ; 
         FIG.  10    is a side view of an example of a height gauge of the apparatus shown in  FIG.  7   ; 
         FIG.  11 A  is a view the example of a pin and a clip in the closed position of the apparatus shown in  FIG.  7   ; 
         FIG.  11 B  is a view the example of a pin and a clip in the open position of the apparatus shown in  FIG.  7   ; 
         FIG.  12 A  is a view the example of an end of the apparatus shown in  FIG.  7    with the clip in the closed position; and 
         FIG.  12 B  is a view the example of an end of the apparatus shown in  FIG.  7    with the clip in the open position. 
     
    
    
     DETAILED DESCRIPTION 
     As used herein, any usage of terms that suggest an absolute orientation (e.g. “top”, “bottom”, “up”, “down”, “left”, “right”, “low”, “high”, etc.) may be for illustrative convenience and refer to the orientation shown in a particular figure. However, such terms are not to be construed in a limiting sense as it is contemplated that various components will, in practice, be utilized in orientations that are the same as, or different than those described or shown. 
     Prior to paving or installing paver stones, a surface is generally graded to provide a smooth and flat finish once the pavement and/or paver stones are placed thereupon. In many applications, the surface to be graded is made from an aggregate material that may be graded using hand tools and/or heavy machinery for larger surfaces. For example, various rakes and straight edges may be used to push and pull the aggregate material to form a flat surface onto which the pavement or paver stones are installed. During the process of pushing and pulling the aggregate material across the surface, it is to be appreciated that the height of the surface may be raised by increasing the amount of aggregate material in an area or lowered by decreasing the amount of aggregate material in the area. 
     In some applications, pavement or paver stones may be installed on a surface bordered by another surface of a different height. For example, the border may include a curb, existing pavement, and/or existing paver stones. When installing the pavement or paver stones, the relative height of the aggregate surface to be graded may be graded to be a constant distance below the height of the border feature. Accordingly, by maintaining the constant height, the pavement installed on the aggregate surface may have a substantially uniform thickness along the border and be flush with the top of the border. Similarly, if paver stones are to be installed over the aggregate surface, the constant distance between the aggregate surface and the border surface may allow for substantially uniform paver stones to be installed flush with the top of the border surface to create a smooth transition from the border. 
     To achieve a substantially constant distance between the aggregate surface and the top surface of a border, the operator of the grading tool is to exercise care and judgement to not push or pull too much aggregate material away or into the areas adjacent to the border. In many instances, the operator of the grading tool is to make multiple measurements to ensure that the distance between the aggregate surface and the top surface of a border is substantially constant. 
     An apparatus is provided to facilitate the grading of an aggregate surface adjacent to a border such that the aggregate surface is maintained at a substantially constant height relative to the top surface of the border. In particular, the apparatus provides a solid height gauge that may be easily attached and detached to a grading tool. By providing a solid height gauge, it is to be appreciate by a person of skill in the art that the height may be maintained even if significant pressure is applied to the height gauge since there are no moving parts that may slip. 
     Referring to  FIG.  1   , a schematic representation of an apparatus  50  to grade a surface proximate to a border is generally shown. It is to be appreciated by a person of skill with the benefit of this description that the apparatus  50  may include additional features and components. For example, the apparatus  50  may also include various attachments for operation by an operator standing up, or connectors to connect to a motorized device to drag the apparatus along the surface. In addition, some of the components described below may be omitted in variations of the apparatus  50 . In the present example, the apparatus  50  includes an elongated member  55  a height gauge  60 , and a connector mechanism  70 . 
     The elongated member  55  includes a straight edge  57  to grade a surface. In the present example, the surface to be graded is typically a surface of aggregate material such that dragging or pushing the elongated member  55  across the surface will cause the aggregate material be graded. The exact design of the elongated member  55  is not particularly limited. For example, the straight edge  57  of the elongated member  55  may be replaced with an attachment or other shape to grade the surface. For example, the straight edge  57  may be substituted with tines or teeth to loosen the aggregate material while grading in some examples. In other examples, the straight edge  57  may include multiple sections, such as a section to loosen the aggregate material followed by a flat section to leave a smooth aggregate surface. In other examples, the elongated member  55  may have a sawtooth structure to provide a sawtooth surface that is graded. 
     The material from which the elongated member  55  is constructed is not particularly limited. In the present example, the elongated member  55  is made from a lightweight metal, such as aluminum. The elongated member  55  may be solid or hollow in various examples. In some examples, alternative metals may be used such as steel, bronze, or other alloys that are typically corrosion resistant. In further examples, the elongated member  55  may also be made from plastic, fiberglass, or other composite materials having sufficient mechanical strength to grade the surface. By using plastics, the elongated member  55  may be made from various processes such as injection molding techniques or three-dimensional printing to allow for modifications and other features to be added to the apparatus  50 , including some of the features discussed below in more detail. 
     The dimensions of the elongated member  55  are not particularly limited and may be varied depending on the application. It is to be appreciated that an elongated member  55  with longer dimensions will be able to grade a large surface area with a single pass; however, the grading process will use more force which may make it more difficult to grade the surface. In the present example, the elongated member  55  may be about 2.0 meters long, about 15 centimeters tall, and about 2.5 centimeters wide. It is to be appreciated by a person skilled in the art that these dimensions provide the ability to grade a wide swath of aggregate material while being able to be controlled by a single user. The cross section dimensions provide sufficient mechanical rigidity for many of the materials mentioned above. Accordingly, for materials with increased structure rigidity, the cross section may be smaller. Similarly, the length of the elongated member  55  may be increased in some applications where additional users or other mechanical devices may be assist in controlling the motion of the apparatus  50 . Alternatively, the elongated member  55  may also have a shorter length for applications where a smaller swath of aggregate material is to be graded, such as for a narrow pathway. 
     The height gauge  60  is to attach to an end of the elongated member  55  using the connector mechanism  70 . The height gauge  60  is to engage a border of the surface that is to be raised above the surface. The manner by which the height gauge  60  engages the border is not particularly limited. In the present example, the height gauge  60  may include fixed shapes such as a substantially square shape formed by the side surface  62  and the bottom surface  63  to engage a border. It is to be understood that for an aggregate surface at the border, any aggregate material buildup next to the raised border may result in an uneven installation, such as a raised paver stone along the border. Accordingly, the substantially square corners provide sharper edges for the installation of a top surface, such as paver stones. 
     In use, the side surface  62  of the height gauge  60  is to engage a side wall of the border. In the present example, it is to be assumed that the side wall of the border is to be substantially vertical. In other examples where the side wall of the border is to be sloped, the side surface  62  is to have a complementary slope to engage with the side wall of the border. Continuing with the present example where the side wall of the border is substantially vertical, the height gauge  60  is dimensioned such that the base of the height gauge  60  is proximate to the side wall of the border when the side surface  62  contacts the side wall of the border. It is to be appreciated by a person of skill with the benefit of this description that by positioning the base of the height gauge  60  proximate to the border of the surface, the base of the height gauge  60  may be used to grade the surface up to the border to provide a square corner. Accordingly, the apparatus  50  may be used to grade along the border without the use of a smaller tool to clean up the edges of the surface against the border. 
     The height gauge  60  also includes a bottom surface  63  that is substantially horizontal to engage the top surface of the border. In the present example, the bottom surface  63  is substantially horizontal and parallel with the straight edge  57 . In particular, the surface  63  is offset from the straight edge  57  by a distance that represents the target height of the top surface of the border relative to the aggregate surface. Accordingly, the surface may be graded by the apparatus  50  until the surface  63  contacts the top of the border. At this point, the apparatus  50  can grade a surface up to a distance equal to the height below the top surface of the border. Accordingly, the height gauge  60  reduces the likelihood of grading the surface too deep. In the present example, the height gauge  60  includes the surface  62  and the surface  63  meeting at a substantially right angle to form a square. In other examples, the height gauge  60  may include other shapes and features that can mate with various border profiles or tracking or guiding mechanisms. 
     The material from which the height gauge  60  is constructed is not particularly limited and may be a plastic material that may be molded to provide a target height from the straight edge  57  to the bottom surface  63 . In other examples, the height gauge  60  may be made from wood, a composite material, or a lightweight metal, such as aluminum. The height gauge  60  may be substantially solid or hollow in various examples. In some examples, alternative metals may be used such as steel, bronze, or other alloys that are typically corrosion resistant. By using plastics, the height gauge  60  may be made from various processes such as injection molding techniques or three-dimensional printing to allow for modifications and other features to be added to the apparatus  50 , including some of the features discussed below in more detail. 
     Referring to  FIGS.  2 A and  2 B , the body of a height gauge  60  is shown in greater detail. The dimensions of the height gauge  60  are not particularly limited and may be varied depending on the application and the dimensions of the raised border to which the height gauge  60  is to engage. It is to be appreciated that the width of the height gauge  60  may be substantially the same as the width of the elongated member  55 , which is about 2.5 centimeters wide in the present example. Similarly, the height of the height gauge  60  may be substantially the same as the height of the elongated member  55 , which is about 15 centimeters tall in the present example. In the present example, the height gauge  60  includes a portion  65  to extend into an opening of the elongated member  55 . The length of the portion  65  is not limited. In the present example, the length of the portion  65  of the height gauge  60  that is to extend from the elongate member  55  is about 10 centimeters long and the surface  63  is about 5 centimeters long (i.e. from the surface  62  to the end of the height gauge  60 ). In the present example, the height gauge  60  has a fixed offset (i.e. the distance from the surface  63  to the bottom of the height gauge  60 , which corresponds with the straight edge  57 ). It is to be appreciate by a person of skill with the benefit of this description that multiple interchangeable height gauges  60  may be used to obtain different offsets. The offset values are not particularly limited and may be about 50 mm, about 60 mm, or about 70 mm. Variations of the height gauge  60  are contemplated and the dimensions and shape may be varied to accommodate other applications or elongated members  55  with other dimensions. 
     Referring again to  FIG.  1   , the connector mechanism  70  is to connect the height gauge  60  to the elongated member  55 . The manner by which the connector mechanism  70  secures the height gauge  60  to the elongated member  55  is not particularly limited and may include various mechanisms. The connector mechanism  70  is to allow for easy attachment of the height gauge  60  to the elongated member  55 . Accordingly, an operator may change the height gauge  60  with another height gauge, such as one with a different height offset between the surface  63  and the straight edge  57  to accommodate different depths below the top surface of the border to the surface to be graded. 
     In the present example, the connector mechanism  70  includes an opening on in the elongated member  55  to receive the portion  65  of the height gauge  60 . As shown in  FIGS.  2 A and  2 B , the portion  65  of the height gauge  60  has smaller dimensions that than the rest of the body of the height gauge  60 . The decrease in dimensions is generally to correspond with the thickness of the walls of the elongated member  55  about the opening such that when the height gauge  60  is attached to the elongated member  55 , the outside surface is substantially flush between the height gauge  60  and the elongated member  55 . 
     The connector mechanism  70  is also to rigidly secure the height gauge  60  to the elongated member  55  such that the height gauge  60  is in a fixed position relative to the elongated member  55  during use. The manner by which the height gauge  60  is secured to the elongated member  55  is not particularly limited and may include various mechanisms. In the present example, the portion  65  of the height gauge  60  may fit tightly in the opening of the elongated member  55  to form a friction fit. Accordingly, a friction fit mechanism provides a quick connecting mechanism to secure the height gauge  60  to the elongated member  55  to allow the height gauge  60  to the elongated member  55  to be connected and disconnected easily without tools. 
     In other examples, the connector mechanism  70  includes other securing mechanisms to secure the height gauge  60  to the elongated member  55 . For example, the connector mechanism  70  may use various fasteners such as a screws or bolts to connect the height gauge  60  to the elongated member  55 . In further examples, a magnetic coupling system may also be used to provide easy interchanging of the components. 
     Referring to  FIG.  3   , a flowchart of a method of grading a surface along a raised border is generally shown at  300 . In order to assist in the explanation of method  300 , it will be assumed that method  300  may be performed by the apparatus  50 . Indeed, the method  300  may be one way in which the apparatus  50  may be configured and used. Furthermore, the following discussion of method  300  may lead to a further understanding of the apparatus  50  and its components. In addition, it is to be emphasized, that method  300  may not be performed in the exact sequence as shown, and various blocks may be performed in parallel rather than in sequence, or in a different sequence altogether. 
     Beginning at block  310 , a height gauge  60  is connected to an elongated member  55 . The manner by which the height gauge  60  is connected to the elongated member  55  is not particularly limited and may involve using the connector mechanism  70  to rigidly connect the height gauge  60  and the elongated member  55  such that they remain locked in a relative position during use when uneven forces may be applied to the height gauge  60  and the elongated member  55 . 
     Block  320  involves engaging the side wall of the raised border with the surface  62  of the height gauge  60 . This process may involve pushing the apparatus against the side wall such that the aggregate material of the surface to be graded cannot be deposited along the raised border, which may ultimately cause uneven paver stones of the surface along the edge. 
     Next, block  330  comprises engaging the surface  63  of the height gauge  60  with the top surface of the raised border. It is understood that the starting height of the surface, as measured by the distance between the surface to be graded and the top surface of the raised border, is to be less than the offset between the surface  63  of the height gauge  60  and the straight edge  57 . Accordingly, as the apparatus is moved, the aggregate surface being graded as in block  340  to remove excess aggregate material from an area until the surface  63  contacts the top surface of the raised border. 
     Referring to  FIG.  4   , another schematic representation of an apparatus  50   a  to grade a surface proximate to a border is generally shown. Like components of the apparatus  50   a  bear like reference to their counterparts in the apparatus  50 , except followed by the suffix “a”. It is to be appreciated by a person of skill with the benefit of this description that the apparatus  50   a  may include additional features and components. In the present example, the apparatus  50   a  includes an elongated member  55   a,  a height gauge  60   a , and a connector mechanism  70   a.    
     The elongated member  55   a  includes a straight edge  57   a  to grade a surface. In the present example, the surface to be graded is typically a surface of aggregate material such that dragging or pushing the elongated member  55   a  across the surface will cause the aggregate material be graded in a similar manner to the elongated member  55 . The material from which the elongated member  55   a  is constructed is not particularly limited and may include similar materials as those described above in connection with the elongated member  55 . 
     The dimensions of the elongated member  55   a  are not particularly limited and may be varied depending on the application. It is to be appreciated that an elongated member  55   a  with longer dimensions will be able to grade a large surface area with a single pass; however, the grading process will use more force which may make it more difficult to grade the surface. 
     In the present example, the elongated member  55   a  includes a level  80   a  to allow an operator to assess and monitor the horizontal level of the apparatus  50   a  as it is being dragged or pushed across the surface. The level  80   a  is not particularly limited and may be disposed on the top surface of the elongated member  55   a.  It is to be appreciated by a person of skill with the benefit of this description that the level  80   a  may also be disposed on a front surface or back surface of the elongated member  55   a.  In further examples, multiple levels  80   a  may be disposed in multiple positions on the elongated member  55   a.  The level  80   a  is not particularly limited and may include any device, such as a bubble level as shown in  FIG.  4   . In other examples, the level  80   a  may be a digital levelling device. 
     Furthermore, the elongated member  55   a  includes handle openings  85   a - 1  and  85   a - 2  (generically, these handle openings are referred to herein as “handle opening  85   a ” and collectively they are referred to as “handle openings  85   a ”) formed therein to extend through the body of the elongated member  55   a . The handle opening  85   a  allows and operator to firmly hold the apparatus  50   a  as it is dragged or pushed along a surface. The handle openings  85   a  may be substituted with a handle extending from the elongated member  55   a  that is either attached or integrally formed with the elongated member  55   a.  For example, the handle may be another elongated member extending substantially vertical or at an angle to allow for an operator to use the apparatus  50   a  from a standing position. 
     The height gauge  60   a  is to attach to an end of the elongated member  55   a  using the connector mechanism  70   a.  The height gauge  60   a  is to engage a border of the surface that is to be raised above the surface. The manner by which the height gauge  60   a  engages the border is not particularly limited and may operate in substantially the same way as the height gauge  60  when attached to the elongated member  55 . 
     Referring to  FIGS.  5 A and  5 B , the body of a height gauge  60   a  is shown in greater detail. The dimensions of the height gauge  60   a  are not particularly limited and may be varied depending on the application and the dimensions of the raised border to which the height gauge  60   a  is to engage. It is to be appreciated that the width of the height gauge  60   a  may be substantially the same width and height of the elongated member  55   a.  The portion  65   a  of the height gauge  60   a  to extend into the opening of the elongated member  55   a  may be similar in dimensions as the portion  65  of the height gauge  60 . Variations of the height gauge  60   a  are contemplated and the dimensions may be varied to accommodate other applications or elongated members  55   a  with other dimensions. 
     The connector mechanism  70   a  is to connect the height gauge  60   a  to the elongated member  55   a.  The manner by which the connector mechanism  70   a  secures the height gauge  60   a  to the elongated member  55   a  is not particularly limited and may include various mechanisms. The connector mechanism  70   a  is to allow for easy attachment of the height gauge  60   a  to the elongated member  55   a . Accordingly, an operator may change the height gauge  60   a  with another height gauge, such as one with a different distance between the surface  63   a  and the straight edge  57   a  to accommodate different target depths of the surface to be graded below the top surface of the border. 
     In the present example, the connector mechanism  70   a  includes an opening on in the elongated member  55   a  to receive the portion  65   a  of the height gauge  60   a.  As shown in  FIG.  2   , the portion  65   a  of the height gauge  60   a  has smaller dimensions that than the rest of the body of the height gauge  60   a.  The decrease in dimensions is generally to correspond with the walls of the opening in the elongated member  55   a  such that when the height gauge  60   a  is attached to the elongated member  55   a,  the outside surface is substantially flush between the height gauge  60   a  and the elongated member  55   a.  Furthermore, in the present example, the height gauge  60   a  includes a pin  75   a  to extend through a hole in the height gauge  60   a  and a hole in the elongated member  55   a  to secure the height gauge  60   a  relative to the elongated member  55   a    
     In the present example, the connector mechanism  70   a  is to rigidly secure the height gauge  60   a  to the elongated member  55   a  such that the height gauge  60   a  is in a fixed position relative to the elongated member  55   a  during use. It is to be understood by a person of skill with the benefit of this description that the connector mechanism  70   a  is to have sufficient mechanical rigidity to secure the height gauge  60   a  to the elongated member  55   a  when subjected to typical forces used to grade an aggregate material and that the forces involved may depend on the type of material being graded. In the present example, the connector mechanism  70   a  includes a pin  75   a  to engage a hole in the body of the height gauge  60   a  and another hole in a wall of the elongated member  55   a.  In particular, the pin  75   a  is dimensioned to fit tightly in the holes to reduce relative motion between the height gauge  60   a  and the elongated member  55   a.    
     Referring to  FIGS.  6 A and  6 B , the pin  75   a  is disposed within the height gauge  60   a.  The pin  75   a  and configured to fit into a hole in the height gauge  60   a . The pin  75   a  may then be aligned to a hole in wall of the elongated member  55   a  into which the portion  65   a  of the height gauge  60   a  is to be inserted. In the present example, the pin  75   a  is moveable between an extended position as shown in  FIG.  6 A  and a retracted position as shown in  FIG.  6 B . The pin  75   a  is also connected to a biasing system, such as a spring  77   a  in the present example. In other examples, the spring  77   a  may be substituted with another resiliently deformable material, to urge the pin toward the extended position. Accordingly, the pin  75   a  may be manually depressed to the retracted position to unlock the height gauge  60  from the elongated member  55   a  to allow for easy and quick detachment. 
     Referring to  FIG.  7   , another schematic representation of an apparatus  50   b  to grade a surface proximate to a border is generally shown. Like components of the apparatus  50   b  bear like reference to their counterparts in the apparatus  50   a , except followed by the suffix “b”. It is to be appreciated by a person of skill with the benefit of this description that the apparatus  50   b  may include additional features and components. In the present example, the apparatus  50   a  includes an elongated member  55   b,  height gauges  60   b - 1  and  60   b - 2  (generically, these height gauges are referred to herein as “height gauge  60   b ” and collectively they are referred to as “height gauges  60   b ”), pins  75   b - 1  and  75   b - 2  (generically, these pins are referred to herein as “pin  75   b ” and collectively they are referred to as “pins”  75   b ), and clips  77   b - 1  and  77   b - 2  (generically, these clips are referred to herein as “clip  77   b ” and collectively they are referred to as “clips  77   b ”). 
     The elongated member  55   b  includes a straight edge  57   b  to grade a surface. In the present example, the surface to be graded is typically a surface of aggregate material such that dragging or pushing the elongated member  55   b  across the surface will cause the aggregate material be graded in a similar manner to the elongated member  55   a.  The material from which the elongated member  55   b  is constructed is not particularly limited and may include similar materials as those described above in connection with the elongated member  55   a.    
     In the present example, the elongated member  55   b  includes a level  80   b  to allow an operator to assess and monitor the horizontal level of the apparatus  50   b  as it is being dragged or pushed across the surface similar to the operation of the level  80   a.  In addition, the elongated member  55   b  includes a vertical level  82   b  disposed on the elongated member  55   b,  such as on a front surface. The vertical level  82   b  is to check the plumb true level of a vertical structure such as a wall. It is to be appreciated by a person of skill with the benefit of this description that the level  82   b  provides additional functionality to the apparatus  50   b  when used at a worksite where vertical structures are built in addition to grading of the surface. 
     The elongated member  55   b  also includes handle openings  85   b - 1  and  85   b - 2  (generically, these handle openings are referred to herein as “handle opening  85   b ” and collectively they are referred to as “handle openings  85   b ”) formed therein. The handle openings  85   b  allow and operator to firmly hold the apparatus  50   b  as it is dragged or pushed along a surface. Referring to  FIG.  8   , each of the handle openings  85   b  may be covered with a handle grip  87   b  to improve comfort during use. In addition, the handle grips  87   b  may improve the grip of the user. 
     In the present example, the height gauges  60   b  is to attach to opposite ends of the elongated member  55   b.  Each height gauge  60   b  is to engage a border of the surface that is to be raised above the surface. The manner by which each height gauge  60   b  engages the border is not particularly limited and may operate in substantially the same way as the height gauge  60  when attached to the elongated member  55 . 
     In the present example, the elongated member  55   b  has an opening at each end as shown in  FIG.  9   . Referring to  FIG.  10   , the portion  65   b  of the height gauge  60   b  is to be inserted into the opening. The elongated member  55   b  further includes an internal support  58   b  to provide additional rigidity to the elongated member  55   b.  The internal support  58   b  is a cross beam along the length of the hollow elongated member  55   b.  In other examples, different support structures may be incorporated into the elongated member  55   b,  such as periodic cross beams, thicker walls, or a filler material. To accommodate the internal support  58   b,  each height gauge  60   b  includes a complementary feature, such as the slot  163   b.  In the present example, the slot  163   b  is dimensioned to fit tightly to engage the internal support  58   b  and provide an additional friction fit. 
     In the present example, the width of the height gauge  60   b  may be substantially the same as the width of the elongated member  55   b,  which is about 1.5 centimeters wide in the present example. Similarly, the height of the height gauge  60   b  may be substantially the same as the height of the elongated member  55   b,  which is about 10 centimeters tall in the present example. In the present example, the height gauge  60   b  includes a portion  65  to extend into an opening of the elongated member  55   b.  In the present example, the length of the portion  65   b  of the height gauge  60   b  that is to extend from the elongate member  55   b  is about 7.5 centimeters long and the surface  63   b  is about 7.5 centimeters long (i.e. from the surface  62   b  to the end of the height gauge  60   b ). In the present example, the height gauge  60   b  has a fixed offset (i.e. the distance from the surface  63   b  to the bottom of the height gauge  60   b,  which corresponds with the straight edge  57   b ). It is to be appreciate by a person of skill with the benefit of this description that multiple interchangeable height gauges  60   b  may be used to obtain different offsets. The offset values are not particularly limited and may be about 50 mm, about 60 mm, or about 70 mm. 
     Referring to  FIGS.  11 A and  11 B , pins  75   b  are used to secure the height gauge  60   b  to the elongated member  55   b.  In the present example, each pin  75   b  is to extend through the opening  59   b  in the elongated member  55   b  and the hole  162   b  through the body of the height gauge and an opening on the opposite side of the elongated member. In the present example, each pin  75   b  includes a clip  77   b  to secure the pin  75   b  in place. The clip  77   b  may be pivotally attached to the pin  75   b  such that it may rotate about a pivot point between a closed position (shown in  FIG.  11 A ) to lock the pin  75   b  when inserted through the elongated member  55   b  and the height gauge  60   b  and an open position (shown in  FIG.  11 B ) to allow for insertion and removal.  FIGS.  12 A and  12 B  illustrate the pin  75   b  in use to secure the height gauge  60   b  to the elongated member  55   b.    
     It is to be appreciated by a person of skill with the benefit of this description that the height gauges  60   b  at opposite end of the apparatus  50   b  allow for both edges of a surface to be graded simultaneously. Accordingly, the dimensions of the elongated member  55   b  are not particularly limited and may be varied depending on the application, such as the width of the surface to be graded. In the present example, the elongated member  55   b  may be about 2.1 meters long, about 10 centimeters tall, and about 1.5 centimeters wide. In other examples, the dimensions may be larger or smaller. 
     Various advantages will not become apparent to a person of skill in the art. In particular, the apparatus  50  may be used to grade various aggregate surfaces having a border. By selecting the height gauge  60  with the correct distance, the apparatus  50  may be used to grade the surface with a high degree of uniformity and precision such that when paver stones are place over the aggregate surface, they can be flush with a border. As an example, the surface may be used as a base for an interlocking driveway and the border may be an edge of a road. Accordingly, by selecting a height gauge  60  substantially close to the thickness of the paver stones, the surface may be graded and the paver stones easily installed to the target height to be flush with the road. Furthermore, by allowing for relatively easy attachment and detachment, multiple border heights may be accommodated by the present example. In addition, the rugged design and fixed size of the height gauge  60  allows for an operator to apply larger forces without recalibrating height settings periodically. 
     It should be recognized that features and aspects of the various examples provided above may be combined into further examples that also fall within the scope of the present disclosure.