Patent Publication Number: US-6712180-B2

Title: Height adjustable sawhorse

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a sawhorse and, more particularly, to a height adjustable sawhorse. The present invention further relates to a sawhorse having independently moving leg members that allow height adjustment to be readily and easily accomplished. 
     2. Description of the Related Art 
     A sawhorse is a movable frame or trestle for supporting wood or another workpiece while it is being sawed or for supporting plates to provide working spaces. A sawhorse typically includes two leg members hingedly connected at the tops thereof and a spread limiting mechanism which defines the working spread at their bottom. 
     Traditionally sawhorses were made of wood or metal, however, following the technological progress of the plastic industry, sawhorses are nowadays also available from plastic materials. 
     For whatever purpose it is employed, it is advantageous for a sawhorse to be adjustable in height because it enables users of different heights to adjust the height of the sawhorse to be most comfortable for them. Sawhorses capable of height adjustment can be used in a wider variety of applications than sawhorses without this capability. 
     Prior art sawhorses are known which are height adjustable. Such devices have extendible/retractable extensions housed by the lower ends of their leg members. One such device is shown in U.S. Pat. No. 6,164,413. This device suffers a limitation because the process of adjusting the height is highly demanding. It requires a user to both adjust individual vertically-adjustable extensions in each sawhorse and secure each vertically-adjustable extension with a respective locking pin during height adjustment all the while holding the vertically-adjustable extension in the adjusted position. 
     It is an object of the invention to provide an improved adjustable sawhorse. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention there is provided a sawhorse comprising an elongated workpiece supporting structure and a pair of leg assemblies. The pair of leg assemblies supports the workpiece supporting structure. Said pair of leg assemblies is movable between a folded position for storage and transportation purposes and an operative position. Connecting structure connects with the leg assemblies below the workpiece supporting structure. The connecting structure is constructed and arranged to retain the leg assemblies in the operative position thereof and to allow movement of the leg assemblies between the operative and folded positions thereof. Each leg assembly includes a pair of separate lower leg members having lower portions. The lower portions are constructed and arranged to engage a horizontal support surface for the sawhorse when the pair of lower leg assemblies is retained in the operative position by the connecting structure thereof. This enables the workpiece supporting structure to be supported at a predetermined height above the horizontal support surface. Each of the lower leg assemblies is mounted for independent movement in a generally vertical direction and can be adjusted to a plurality of different positions with respect to the associated leg assembly and the connecting structure while the pair of the leg assemblies are retained in the operative position thereof by the connecting structure. A releasable locking member for each leg member is mounted in the connecting structure for movement between a releasing position and a locking position. In the releasing position, the releasable locking member is operable to release the associated leg member from movement into a selected one of the plurality of adjusted positions thereof. In the locking position, the releasable locking member is operable to lock the associated leg member within the adjusted position selected. 
     In another embodiment of the invention, the releasable locking member is spring biased into the locking position thereof for movement between the releasing and locking positions. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention herein described, by way of example only, with reference to the accompanying drawings in which like reference numerals designate like elements and wherein: 
     FIG. 1 is a perspective view of a height adjustable sawhorse according to the principles of the present invention shown in a height retracted position; 
     FIG. 2 is a second perspective view of the sawhorse of FIG. 1, two leg members of which are shown in a deployed (vertically extended) position; 
     FIG. 3 is a side view of the height adjustable sawhorse of FIG. 1 in the operative position; 
     FIG. 4 is a side view of the height adjustable sawhorse of FIG. 1 in the folded, closed position; 
     FIG. 5 is a front view of the height adjustable sawhorse of FIG. 1 in the operative position; 
     FIG. 6 is a detail view of a releasable locking member encircled in FIG. 5; 
     FIG. 7 is a cross-sectional view of the height adjustable sawhorse taken through line  7 — 7  of FIG. 1 shown a releasable locking member in its locking position; and 
     FIG. 8 is a cross-sectional view of the height adjustable sawhorse shown in FIG. 7, but showing the releasable locking member in its releasing position. 
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
     The present invention is directed to a height adjustable sawhorse which can be height adjusted for different users and/or applications. The present invention is further directed to a sawhorse having independently moving leg members that allow height adjustment to be readily and easily accomplished even while the sawhorse is in an operative position. 
     The principles and operation of a sawhorse according to the present invention may be better understood with reference to the drawings and accompanying descriptions. 
     Referring now to the drawings, FIGS. 1-8 illustrate one embodiment of a sawhorse, generally indicated at  10 , according to the principles of the present invention. The sawhorse  10  includes a pair of leg assemblies  12 ,  14  that are pivotally connected at their upper ends along a pivot axis  16 . The leg assemblies  12 ,  14  are pivotally connected to be moved between a folded position for storage and transportation purposes (FIG. 4) and an operative position (FIGS.  1 - 3 ). An elongated workpiece supporting structure  18  having an upwardly facing workpiece supporting surface  17  is located generally at the upper ends of the leg assemblies  12 ,  14  and is supported at a predetermined height above a horizontal support surface  19  for the sawhorse  10 . The workpiece supporting structure  18  may include indicia  21 , such as measurement indicia, printed or formed thereon. 
     Connecting structure  20  is connected with the leg assemblies  12 ,  14  below the workpiece supporting structure  18 . The connecting structure  20  is constructed and arranged to retain the leg assemblies  12 ,  14  in the operative position thereof and to allow movement of the leg assemblies  12 ,  14  between the operative and folded positions thereof. The connecting structure  20  includes a releasable locking member, generally indicated at  22 , operable to allow movement between a releasing position and a locking position to at least partially control height adjustment of the workpiece supporting structure  18 , as will be described in further detail below. 
     The leg assemblies  12 ,  14  may be substantially identical in construction and operation and accordingly, a description of the leg assembly  12  will suffice for an understanding of both leg assemblies  12 ,  14 . The leg assemblies  12 ,  14  can be formed of the same construction such that only one die or mold can be used to manufacture both leg assemblies  12 ,  14 . Accordingly, like reference numerals designate similar elements of the leg assemblies  12 ,  14 . 
     The leg assembly  12  includes an upper connecting member  24  that extends along the workpiece supporting structure  18  and may be pivotally connected thereto, for example, by pivot rod  26 . Other pivot mechanisms or hinges can be employed as well, such as that disclosed in U.S. Pat. No. 6,305,498, the contents of which are hereby incorporated by reference in its entirety. The upper connecting member  24 , which may be formed of plastic, for example, may further include a manually engageable handle  27  for storage and transporting purposes when the sawhorse  10  is in its folded position or for assisting in the height adjustment of the workpiece supporting structure  18 . Alternatively, the upper connecting member  24  can be formed of metal or any other suitably rigid material. 
     The leg assembly  12  further includes a pair of upper leg members  28 , 30  spaced from one another by the upper connecting member  24  and a pair of lower leg members  32 ,  34  (FIG. 2) associated with respective upper leg members  28 ,  30 . The upper leg members  28 ,  30  and the lower leg members  32 ,  34  can each be formed of metal, plastic or another suitably rigid material. However, it may be preferable for the upper and lower leg members  28 ,  30 ,  32 ,  34  to be formed of a relatively strong and light weight material, such as extruded aluminum. It may also be preferable for the lower leg members  32 ,  34  to be formed of an extruded or molded polymer material. 
     The upper connecting member  24  is of elongated hollow cross-sectional configuration sized with respect to the upper leg members  28 ,  30 . The upper leg members  28 ,  30  are received in respective downwardly extending end portions  36 ,  38  of the upper connecting structure  24 . The upper leg members  28 ,  30  are fixedly secured to the downwardly extending end portions  36 ,  38  with a plurality of fasteners  40  so to extend generally downward therefrom when the leg assemblies  12 ,  14  are in the operative position thereof. The fasteners  40  may be, for example, rivets, screws, bolts or some other fastening device capable of fixedly securing the downwardly extending end portions  36 ,  38  of the upper connecting structure  24  to the upper leg members  28 ,  30 . 
     A tool carrier member (not shown) could be provided on an outside surface of the upper connecting structure  24  and attached thereto via the fasteners  40 , for example. An example of such a tool carrier member is shown in U.S. Pat. No. 6,305,498, incorporated by reference above. 
     The connecting structure  20  includes a lower connecting member  42  associated with each leg assembly  12 ,  14  that is connected to lower portions  39 ,  41  of the upper leg members  28 ,  30  thereof. The lower connecting members  42  each have downwardly extending portions  44 ,  46 , which are of elongated hollow cross-sectional configuration sized with respect to the upper leg members  28 ,  30 , so as to receive therein the lower portions  39 ,  41  of the upper leg members  28 ,  30 . The lower portions  39 ,  41  of the upper leg members  28 ,  30  extend through interiors of the downwardly extending portions  44 ,  46 , respectively, and are fixedly secured thereto with a plurality of fasteners, such as the fasteners  40 , for example. A cross brace  43  extends from the downwardly extending portion  44 , along the underside of the lower connecting member  42  and to the downwardly extending portion  46  to support the leg assemblies  12 ,  14 . An opening can be formed through the lower connecting member  42  to provide a handle portion  45  for manual engagement or gripping by a user. It is contemplated that the connecting structure  20  may be formed of any suitable material, such as polymer or metallic material. It may be preferable, however, for the connecting structure  20  to be formed by molding a polymer material, for example. 
     FIGS. 2 and 3 show a foldable tray assembly  48  that can be pivotally connected between the lower connecting members  42  with a hinge structure  49  (FIG.  3 ). The foldable tray assembly  48  is associated with the leg assemblies  12 ,  14  such that movement of the sawhorse  10  between its folded and operative positions moves the foldable tray assembly  48  between an inoperative, folded position and an operative limiting position. In the operative limiting position, as shown in FIG. 3, the foldable tray assembly  48  acts both as a shelf and to limit the operative spread of the leg assemblies  12 ,  14  in the operative position thereof. In other words, when the foldable tray assembly  48  is in its operative limiting position, the foldable tray assembly  48  limits the outward movement of the leg assemblies  12 ,  14  in their opening direction. One example of such a foldable tray assembly is shown in U.S. Pat. No. 6,298,946, the contents of which are hereby incorporated by reference in their entirety. 
     As best shown in FIG. 3, the lower connecting members  42  are configured to secure the sawhorse  10  in the folded position. More particularly, each lower connecting member  42  has a bayonet pin portion  51  and a barrel portion  53  extending inwardly from the cross brace  43  at opposite ends thereof. As illustrated, each bayonet pin  51  engages the associated barrel portion  53  upon convergence of the leg assemblies  12 ,  14  when the leg assemblies  12 ,  14  are moved into the folded position, as shown in FIG. 4. A press fit between the bayonet pins  51  and the associated barrel portions  53  can retain the leg assemblies  12 ,  14  in the folded position for storage or transportation purposes. 
     Another option (not shown) for retaining the leg assemblies  12 ,  14  in the folded position might be to include a hook-and-eyelet latch. The sawhorse might have one or more such hook-and-eyelet latches. One leg assembly, e.g.  12 , may have a hook member extending toward the other leg assembly, which may have an eyelet member that the hook member engages when the sawhorse is in the folded position. 
     The upper leg members  28 ,  30  are of elongated hollow cross-sectional configuration sized with respect to a cooperating lower leg member  32 ,  34 , respectively, so as to telescopically receive the same therein for relative rectilinear movement in opposite substantially vertical directions (FIGS.  7  and  8 ). As shown in FIGS. 2 and 3, the lower leg members  32 ,  34  have lower portions  50 ,  52 , in the form of cantilevered foot portions, that are constructed and arranged to engage the horizontal support surface  19  for supporting the workpiece supporting structure  18  at a predetermined height above the horizontal support surface  19 . The lower portions  50 ,  52  may be supplemented with anti-slip rubber insets (not shown) to prevent slippage of the sawhorse  10  when in use, or may themselves be formed of a non-slip material, such as rubber. 
     A securing structure  55  (FIG. 2) may be used to secure the lower portions  50 ,  52  to the lower leg members  32 ,  34 . The securing structure  55  may be constituted by, for example, a protrusion projecting from the lower portions  50 ,  52  and received in a recess formed in the lower leg members  32 ,  34 . Other forms of securing structure may be used as well, such as, fasteners, adhesives and press-fit engagements, for example. 
     As shown in FIG. 2, each lower leg member  32 ,  34  is mounted to an associated upper leg member  28 ,  30  for independent movement in a relative rectilinear vertical direction while the sawhorse  10  is in the operative position thereof. This construction enables a user to extend or retract one or more of the lower members  32 ,  34  independently relative to the upper leg members  28 ,  30  to readily adjust the height of the workpiece supporting surface  17  relative to the horizontal support surface  19  (FIG.  1 ). In this manner, the sawhorse  10  may be adjusted, for example, according to heights of different users or needs of a particular application. Additionally, the lower leg members  32 ,  34  may be adjusted individually to allow the angle and level of the workpiece supporting surface  17  to be adjusted relative to a level and/or contour of the horizontal support surface  19 . 
     The fasteners  40  connecting the upper leg members  28 ,  30  and the downwardly extending end portions  44 ,  46  extend through the lower leg members  32 ,  34  to secure the lower leg members  32 ,  34  to the upper leg members  28 ,  30 . The lower leg members  32 ,  34  can be adjusted to a plurality of different positions with respect to the associated upper leg member  28 ,  30  and the lower connecting member  42 . Adjustment of the lower leg members  28 ,  30  is performed while the leg assemblies  12 ,  14  are retained in the operative position thereof by the connecting structure  20  in response to movement of the releasable locking member  22 , as will be described in greater detail below. 
     FIG. 2 shows each lower leg member  32 ,  34  including stop structure in the form of a vertically elongated slot  62  formed through opposite sides (e.g., an exterior side and an interior side) thereof. The stop structure of the lower leg members  32 ,  34  engages the fasteners  40  associated with the upper leg members  28 ,  30 . The fasteners  40  constitute cooperating stop structure to the vertically elongated slot  62 . The vertically elongated slot  62  has a lower end  63  and an upper end  65  defined by end surfaces of the respective lower leg members  32 ,  34 . The upper and lower ends  63 ,  65  of the vertical slot  62  cooperate with the fasteners  40  to limit the rectilinear movement of each lower leg member  32 ,  34  with respect to the respective upper leg member  28 ,  30 . The upper end  63  of the elongated slot  62  limits downward movement while the lower end  65  in combination with the lower portions  50 ,  52  limits upward movement of each lower leg member  32 ,  34 . 
     The upper leg members  28 ,  30  include a pair of openings  54 ,  56  formed on opposite ends thereof (openings  54 ,  56  are shown in FIG.  6 ). Similarly, the lower leg members  32 ,  34  include a series of openings  58 ,  60  (FIGS. 6-8) integrally formed therein. The openings  54 ,  56 ,  58 ,  60 , (as shown in FIGS. 6-8) are constructed and arranged to accept and lockingly engage portions of the releasable locking member  22 . The lockingly engaged portions of the releasable locking member  22  are provided by a pair of locking pins  61  positioned in the access openings  58 ,  60  of the lower connecting members  42 . As discussed above, the upper leg members  28 ,  30  can have identical structure and the lower leg members  32 ,  34  can have identical structure for easy manufacture. 
     Each lower connecting member  42  includes a pair of opposing outwardly facing receptacles  64  formed therethrough within each of which one releasable locking member  22  for each upper leg member  28 ,  30  is mounted. Each lower connecting member  42  also includes a pair of exteriorly facing access openings  67  to allow manual operation of the releasable locking members  22 . Each releasable locking member  22  is operable for movement between a releasing position and a locking position. In the releasing position, the releasable locking member  22  is operable to release an associated lower leg member  32 ,  34  from movement into a selected one of the plurality of adjusted positions thereof (as determined by the series of openings  58 ,  60  formed therein). In the locking position, the releasable locking member  22  is operable to lock the associated lower leg member  32 ,  34  within the adjusted position selected (where the locking pins  61  engage the openings  58 ,  60 ). Movement of each released lower leg member  32 ,  34  into a selected adjusted position while the pair of leg assemblies  12 ,  14  is retained in the operative position thereof by the connecting structure  20  allows the workpiece engaging structure  18  to be supported at different heights (selected by the user) above the horizontal support surface  19 . 
     As shown in FIGS. 7 and 8, each receptacle region  64  is defined by an end wall  66  and a pair of oppositely facing side walls  68 . The end wall  66  and side walls  68  of each receptacle region  64  are configured so that each receptacle region  64  has an open portion  70  facing the respective upper leg member  28 ,  30 . The side walls  68  have a recess  72  formed therein, which is configured to slidably receive a flange portion  74  of the releasable locking member  22 . Each releasable locking member  22  is slidably mounted in each receptacle region  64  to allow relative horizontal rectilinear movement of the releasable locking member  22 . Alternatively, the side walls  68  can slidably engage the releasable locking member  22  without forming the recess  72  in the side walls  68 . 
     The open portion  70  is positioned to align with the openings  54 ,  56  in the upper leg members  28 ,  30  and with the series of openings  58 ,  60  in the lower leg members  32 ,  34 , respectively. In this manner, each releasable locking member  22  may slide within each receptacle region  64  to effect generally horizontal rectilinear movement through the open portion  70 . In doing so, the locking pins  61  of the releasable locking member  22  can engage the openings  54 ,  56  in the upper leg members  28 ,  30  and can engage one of the series of openings  58 ,  60  in the lower leg members  32 ,  34  to support the workpiece engaging structure  18  at different heights (selected by the user) above the horizontal support surface  19 . 
     The releasable locking member  22  includes a manually engageable portion  76 , in the form of a circular portion or tab, that is manually engageable by a user through the access opening  67  to slide the releasable locking member  22  between its releasing and locking positions. A spring  78 , as shown in FIG. 6, may be mounted between each releasable locking member  22  and each end wall  66  of the lower connecting structure  42  for biasing the locking pins  61  of the releasable locking member  22  toward and into the locking position thereof. 
     The height of the workpiece supporting structure  18  can, therefore, be easily adjusted by selectively adjusting the position of the lower leg members  32 ,  34  with respect to the upper leg members  28 ,  30 . The lower leg members  28 ,  30  are normally placed in their lowermost position (FIG. 1, for example) when the sawhorse  10  is stored. To raise the position of the workpiece supporting structure  18 , the user lifts the same, while standing on the lower portions  50 ,  52  and releasing a selected releasable locking member  22 , for example, thereby causing the locking pins  61  of the selected releasable locking member  22  to move outwardly against the bias of the spring  78 . When the locking pins  61  are released from the aligned openings  54 ,  56  and  58 ,  60 , as shown in FIG. 6, rectilinear movement of the lower leg members  32 ,  34  with respect to the associated upper leg member  28 ,  30  is allowed. A user needs to release only one or more of the releasable locking members  22  at a time, or alternatively, may simultaneously release all of the releasable locking members  22 , because the lower leg members  32 ,  34  may be independently extended and need not be extended at the same time. 
     It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting. 
     For example, workers using sawhorses typically use power tools in conjunction therewith. It is therefore frequently necessary to have a source of electrical power at the work site where the sawhorses are being used. Electrical power is usually provided at a work site by electrical outlets and by electrically conductive extension cords. In alternative embodiments not shown, a plurality of attachments could be provided by the invention for use with the sawhorse  10  to mount an electrical power cord on the sawhorse  10  for power cord storage and used, for example. In other alternative embodiments not shown, a plurality of attachments could also provided by the invention to mount a power strip to the sawhorse  10  to provide a plurality of electrical outlets at the work site. 
     Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.