Patent Publication Number: US-2017370715-A1

Title: Expandable level

Description:
TECHNICAL FIELD 
     The present invention is generally directed to a level used for determining whether a workpiece is in a horizontal or vertical plane. In particular, the present invention is directed to an expandable level. More specifically, the present invention is directed to an expandable level that utilizes a straight edge assembly to allow a user to draw a line even though the level is in its expanded condition. 
     BACKGROUND ART 
     As is well known, levels are used to make sure a workpiece is in a horizontal or vertical plane. Ensuring that a workpiece is level to another workpiece for attachment purposes provides for ideal construction practices. If the workpiece is not level, the finished project is likely not structurally sound, and additionally provides, in most instances, an unpleasing appearance. 
     Different size levels are available depending on a particular application. However, large or long-length levels are too cumbersome to carry in a toolbox. Accordingly, small levels are used, but these levels do not provide, in some instances, an adequate length to provide for a consistent and accurate determination of whether an object is level or not. Additionally, if an edge of the level is used to make a straight line marking, the short length level is not long enough to provide for an adequate mark. As a result, a number of expandable or telescoping levels have been developed. These allow for a small length level to work almost as effectively as a longer level. 
     One distinct disadvantage of an expandable or telescoping level is that the level does not provide for a straight line edge. In other words, in an expanded condition, the level has a gap between expanded portions and the workpiece which is being analyzed to determine whether it is level or not. As such, once a workpiece or a line to be drawn on the workpiece is determined to be level, a user trying to draw the line to represent that level position will encounter a gap between the portions of the level not adjacent the workpiece and the workpiece. As such, a continuous and accurate straight line edge cannot be obtained. Therefore, there is a need in the art for an expandable level that also provides for a straight line edge adjacent the workpiece. 
     SUMMARY OF THE INVENTION 
     In light of the foregoing, it is a first aspect of the present invention to provide an expandable level. 
     It is another aspect of the present invention to provide an expandable level, comprising a pair of extension bodies, at least one of the extension bodies carrying a level indicator, each body having a carriage with a carriage cavity, the carriage cavities aligned with each other, and each carriage having a pair of exterior top surfaces separated by the carriage cavity, and a rail slidably received in both carriage cavities, the rail having a body surface that remains substantially flush with the exterior top surfaces when the pair of extension bodies are adjacent one another and when the pair of extension bodies are spaced apart from one another. 
     Yet another aspect of the present invention is to provide an expandable level, comprising a pair of extension bodies, at least one of the extension bodies carrying a level indicator, each extension body having a carriage cavity and an exterior surface, a rail slidably received in the carriage cavities, the rail having a body surface that remains substantially flush with the exterior surfaces when the pair of extension bodies are adjacent one another and when the pair of extension bodies are spaced apart from one another, and a straight edge assembly slidably secured to the pair of extension bodies so as to provide a straight line edge when the pair of extension bodies are spaced apart from one another. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings wherein: 
         FIG. 1  is a perspective view of an expandable level made in accordance with the concepts of the present invention; 
         FIG. 2  is a perspective view of the expandable level shown in an expanded condition according to the concepts of the present invention; 
         FIG. 3  is a cross-sectional view taken along lines  3 - 3  of  FIG. 1  showing the expandable level according to the concepts of the present invention; 
         FIG. 4  is a rear perspective view of the expandable level in the expanded condition in accordance with the concepts of the present invention; 
         FIG. 5  is an elevational view of the expandable level in the expanded condition according to the concepts of the present invention; 
         FIG. 6  is a top view of the expandable level in the expanded condition according to the concepts of the present invention; 
         FIG. 7  is a partial exploded perspective view of selected components of the expandable level illustrating features of a straight edge assembly employed by the expandable level according to the concepts of the present invention; 
         FIG. 8  is a detailed cross-sectional view of the straight edge assembly according to the concepts of the present invention; 
         FIG. 9  is a perspective view of an expandable level according to the concepts of the present invention showing an alternative embodiment of the straight edge assembly in accordance with the concepts of the present invention; 
         FIG. 10  is a partial exploded perspective view showing selected components of the expandable level illustrating features of the alternative straight edge assembly according to the concepts of the present invention; and 
         FIG. 11  is a detailed cross-sectional view taken along lines  11 - 11  of  FIG. 9  showing the alternative straight edge assembly according to the concepts of the present invention. 
     
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     Referring now to the drawings and in particular to  FIGS. 1-8 , it can be seen that an expandable level according to the concepts of the present invention is designated generally by the numeral  10 . The level  10  includes two extension bodies, each designated generally by the numeral  12 . For the most part, the extension bodies  12  are mirror images of one another, wherein one of the bodies  12  is shown on the left side of  FIGS. 1 and 2  while the other extension body  12  is shown on the right side of  FIGS. 1 and 2 . Each extension body  12  provides an end  14 , wherein each end is at an opposite end of the level  10 . Each extension body  12  has a face  16  that is opposite its respective end and which is adjacent each other when the level  10  is in its collapsed position as shown in  FIG. 1 . 
     Each extension body provides a web designated generally by the numeral  20 . In the embodiment shown, the web is shaped like an I-beam, but it will be appreciated that other structural shapes may be employed. As best seen in  FIG. 3 , the web  20  provides for a beam  22  which makes up a middle portion of the web. Each web  20  is terminated at one end by the end  14  and at an opposite end by the face  16 . Each edge of each beam  22  provides a pair of substantially perpendicularly extending shoulders  24 . The beam  22  carries at least one level indicator designated generally by the numeral  28 . The level indicators may be of the bubble configuration, but other configurations may be employed. In the embodiment shown, one of the level indicators is partially carried at the face  16  of one of the extension bodies and a corresponding notch  30  in the other extension body receives the other portion of the level indicator when the extension bodies are spaced apart from one another as shown in  FIGS. 2 and 4 . 
     Secured to each shoulder of the extension bodies  12  on both sides thereof may be an extension member  40 . The extension members  40  may be welded, adhesively secured, or in some embodiments, integral with the shoulders  24 . The extension member  40  includes a carriage  42  which is generally U-shaped in cross-section. The carriage includes a base  44  which may extend from the end  14  to the face  16 . Extending substantially perpendicularly from the base  44  are a pair of opposed arms  46 . Each arm  46  provides an exterior side surface  48  that faces outwardly. In the embodiment shown the exterior side surfaces  48  are substantially flush with an outer exterior edge of each shoulder  24 . In some embodiments, the exterior side surface  48  may extend beyond the outer exterior edge of the corresponding shoulder  24 . Skilled artisans will appreciate that the extension members  40  will all be of substantially the same width. 
     Each arm  46  maintains a channel  50  therein which extends substantially along the entire length of each arm  46 , wherein the channel in one arm faces the channel in the other facing arm. Each channel  50  may further provide a trough  51 . Each arm  46  also provides an exterior top surface  52  which is substantially perpendicular to the exterior side surface  48 . In any event, the channel  50  may be disposed anywhere along the arm, but in the embodiment shown the channels are positioned proximally near the base  44 . The arms  46  are opposed to one another and form a carriage cavity  54 . As best seen in  FIG. 3 , one side of a single arm  46  along the adjacent exterior side surface  48  and the exterior top surface  52  provides for a groove  56 . Although the groove  56  is only shown in relation to one of the arms  46 , it will be appreciated by skilled artisans that the groove  56  may be provided on any one or all of the outer corners of the arms  46 . As best seen in  FIG. 7 , each groove  56  is formed by a wall  58  that extends perpendicularly downwardly from the exterior top surface  52 . Extending substantially perpendicularly from the wall  58  is a ledge  60  which extends to the outwardly facing exterior side surface  48  of the arm  46 . Further details about the groove  56  will be discussed later. 
     Slidably received in the carriage cavity  54  is a rail designated generally by the numeral  70 . The rail  70  includes a body  72  which has a body surface  74 . In the embodiment shown, the body surface  74  is substantially flush with the exterior top surface  52  provided by the respective arms  46 . As such, it will be appreciated that together the exterior top surfaces  52  and the body surface  74  provide a substantially flat planar surface for the level  10  when it is applied to a workpiece or object to determine whether the workpiece is in a level condition or not. At a lower edge of the body  72  may be a pair of opposed ribs  72 . As best seen in  FIG. 3 , the ribs  76  are slidably received in the respective channels  50 . Further extending from each rib  76  at one end thereof may be a knob  78 . Each knob  78  is slidably received in the corresponding trough  51 . The knob  78  may be a fixed outwardly extended pin or a spring-loaded pin that can be pushed inwardly to facilitate insertion of the rail  70  into the carriages  42  and specifically the carriage cavities  54 . The knobs  78  are employed to catch on an end surface provided by each channel so that the extension bodies do not become disconnected from the rails  70  when the level is expanded. Skilled artisans will appreciate that other retention mechanisms may be employed so as to keep the extension bodies and the rail associated with one another. 
     As presented, the level  10  provides a rail  70  that may be slidably received in both carriage cavities along opposed sides of the extension bodies. Each rail has a body surface  74  that remains substantially flush with the exterior top surface  52  of the arms when the pair of extension bodies are adjacent one another. When the extension bodies  12  are spaced apart from one another, the exterior top surface  52  of the arms remain flush with the body surface  74  of the rail in those positions where the rail  70  is still received in the carriage cavity  54 . This is in distinct contrast to prior art expandable levels which utilize a telescoping feature or other configuration wherein the surface of the level that is maintained adjacent the object being evaluated has a significant gap therebetween which does not permit a user to draw a straight line for later positioning and then attaching another piece of material to the first piece of material. Skilled artisans will appreciate that the width of each arm  46  may be minimized so that when the extension bodies are spaced apart from one another, only a minimal gap between the rail and the workpiece surface upon with the level is placed is generated. As such, the expanded level  10  can provide a substantially straight edge that can be used when marking a straight line on the workpiece. 
     To further assist and ensure that a straight edge can be provided by the level when it is in an expanded condition, a straight edge assembly designated generally by the numeral  88  may be provided with the level  10 . In such a configuration, the straight edge assembly  88  allows for the extension bodies to be separated from one another and provide for a straight line edge in substantially the middle portion of the expanded level that is in substantially touching contact with the adjacent workpiece. 
     The straight edge assembly  88  may be received in one or all of the grooves  56  provided by each extension body  12 . A pin  90  may extend from the wall  58  near the face  16  of each extension body. Specifically, as best seen in  FIGS. 7 and 8 , each pin  90  is connected to a corresponding wall  58 . Each pin  90  has a shaft  92  and a pin head  94  connected to the shaft. The effective outer diameter of the pin head is larger than the effective outer diameter of the shaft. The shaft  92  may be a threaded member for connection to the wall or the shaft may be fastened by other means. Each pin head  94  may provide an underside surface  96 . In some embodiments the underside  96  may be a chamfered configuration instead of a substantially perpendicular configuration as shown. The pin  90  may be connected to the wall  58  such that the pin head  94  is substantially flush with the exterior side surface  48  of the arm  46 . In other words, the pin head  94  and the exterior side surface  48  are coplanar so that the level, when positioned on its side, lies substantially flat on the workpiece. 
     The straight edge assembly  88  also includes an inner frame  100  and an outer frame  120  that are both slidably secured by the pins  90  to the extension bodies. The inner frame  100  includes an external edge  102  which is aligned and substantially flush with the exterior top surface  52  of the arm  46 . Opposite the external edge  102  is an internal edge  104  which is maintained slidably adjacent the ledge  60  provided by the groove  56 . The edges  102  and  104  are connected by corresponding sides  106 . The inner frame  100  provides an arm surface  110  that faces the wall  58 . The inner frame  100 , opposite the arm surface  110 , provides a frame surface  112 . The inner frame  100  maintains an elongated slot  108  that extends from the arm surface  110  to the frame surface  112 . The slot  108  is sized to allow for slidable movement past the shafts  92 . 
     The outer frame  120  provides for an external edge  122  that is aligned and substantially flush with the exterior top surface  52  of the arm  46 . Opposite the external edge  122  is an internal edge  124  which is maintained slidably adjacent the ledge  60 . The edges  122  and  124  are connected to one another by opposed sides  126 . The outer frame  120  includes an outer surface  128  that is substantially flush with the exterior side surface  62  of the arm  46 . The outer frame  120  also provides a facing surface  130  that is positioned slidably adjacent to the inner frame&#39;s outwardly facing frame surface  112 . Extending through the outer frame  120  is an elongated slot  132  which is sized to be slightly larger than the diameter of the shafts  92 . Extending from the slot  132  is a step  136  that extends substantially along the entire length of the slot  132 . The step  136  is positioned adjacent the pin&#39;s underside  96 . As a result, the pin head  94  functions to capture and slidably maintain the outer frame  120  and the inner frame  100  within the groove  56 . 
     In operation, when the user positions the level on a workpiece to determine whether it is level or not, the level provides for a straight edge assembly upon which the user can make an appropriate straight line marking. If needed, the level can be expanded by pulling the two extension bodies apart from one another. As this occurs, the extension bodies slide apart and are slidably supported by the rail  70  which is maintained within the respective carriage cavities  54 . As the extension bodies are pulled apart from one another the straight edge assembly  88 , which is maintained within the groove  56 , expands accordingly with the extension bodies. Eventually, at least one of the pins  90  engages the inner and/or outer frames so that they likewise pull apart. This pulling apart however maintains a straight edge in between the extension bodies so that a straight line marking can be obtained. 
     Referring now to  FIGS. 9-11 , it can be seen that an alternative straight edge assembly designated generally by the numeral  88 ′ may be provided. In this embodiment, prime numbers are utilized to indicate components which are similar to the components shown in the prior embodiment. In this embodiment, instead of utilizing an inner frame and an outer frame, only a single outer frame is provided. An outer frame  120 ′ extends substantially the entire length of the two extension bodies and, as such, allows for the level to be expanded further than provided by the previously described straight edge assembly  88 . As such, the outer frame  120 ′, in a manner similar to the previously described outer frame, provides for an external edge  122 ′ that is substantially aligned and flush with the exterior top surface  52 . Opposite the external edge  122 ′ is an internal edge  124 ′ which is maintained slidably adjacent the ledge  60 . Each of the edges  122 ′ and  124 ′ are connected by sides  126 ′. The outer frame  120 ′ provides for an outer surface  128 ′ that is maintained substantially flush with the outer surface  48  and a surface of the pin head. The outer frame  120 ′ provides for a slot  132 ′ that extends substantially therethrough. Extending from the slot  132 ′ is a step  136 ′ that may extend substantially along the entire length of the slot. As in the previous embodiment, the slot  132 ′ is sized to be slightly larger in width than the diameter of the shafts  92 . The pin head  94 ′ is sized to be larger than the width of the slot  132 ′ such that the underside  96 ′ is slidably adjacent the step  136 ′ so that the outer frame  120 ′ is held slidably in place. Accordingly, in this embodiment the extension bodies are allowed to extend as far as the length of the slot  132 ′. In other words, the pins will travel within the slot until they come in contact with the end of the respective ends of the slot  132 ′. 
     This configuration allows for the level to be extended a larger amount than the previous embodiment. Otherwise the advantages are substantially the same in that the straight edge assembly provides for a straight line for marking a workpiece whenever the level is fully expanded. And in both embodiments of the slide edge assembly  88  and  88 ′, the assembly assists in maintaining the extension bodies  12  associated with one another. 
     Thus, it can be seen that the objects of the invention have been satisfied by the structure and its method for use presented above. While in accordance with the Patent Statutes, only the best mode and preferred embodiment has been presented and described in detail, it is to be understood that the invention is not limited thereto or thereby. Accordingly, for an appreciation of the true scope and breadth of the invention, reference should be made to the following claims.