Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is in the field of fencing hardware including gate latches and pertains particularly to methods and apparatus for latching a gate. 
     2. Discussion of the State of the Art 
     In the art of fence construction, gate-latching apparatus are used to affect latching between a swing gate and a gatepost. The most common latches are vertical latches that, with the aid gravity and a passive bar grabbing design function to latch gates to prevent entrance to or egress from a fenced area. 
     Many vertical latch assemblies include a flat mounting plate and latch housing with a pivotally mounted latching plate disposed within the latch housing. Gravity keeps the latch plate in the closed position. A rounded front face on the latch plate allows a latch bar to be inserted into the latching position of the assembly, such action lifting the latch plate just enough to accept the bar. Gravity then urges the latch plate down over the latch bar providing a latched gate. 
     A challenge with these latches is that there are no operational components for opening and closing the latch. A user swings the gate closed to affect latching and manually lifts up on the latch to release the gate. This is not practical if the gatepost and gate are very tall because the user generally has to reach over the top of the gate to reach the latch assembly in order to unlatch the gate. 
     In some cases, a hole is drilled through the gatepost and a wooden handle and rope or string is used to connect to the latch assembly through the gatepost to the handle that can be used to pull the latch plate upward, thus releasing the gate. A problem with this approach is that a wooden handle hanging from a string is not aesthetic. Likewise, the latch plate may kink, become slightly rusted, etc. which may prevent gravity from re-closing the latch plate when the string or rope handle is released. Moreover, the rope or string connecting the latch plate to the handle can be easily compromised by wear and tear, rot, or other compromising condition rendering the method less effective at opening and closing the gate. 
     Therefore, what is clearly needed is a vertical gate latch that solves the above limitations. 
     SUMMARY OF THE INVENTION 
     The problem stated above is that consistency of successful operation is desirable for a vertical gate pull latch, but many of the conventional means for operating a vertical pull latch, such as string or rope applicators do not provide consistent operation. The inventors therefore considered functional components of a vertical gate pull latch, looking for elements that exhibit interoperability that could potentially be harnessed to provide consistent successful operation but in a manner that would not create uncertainty in operational integrity. 
     The present inventor realized in an inventive moment that if during the operation the latch plate could be caused to close correctly against a mild spring pressure significant improvement in consistent operation might result. The inventor therefore constructed a unique gate latch for installation on wooden or metal gateposts that allowed a user to unlatch the gate by pulling the vertical latch up against a mild spring tension that also worked to urge the latch into the closed position when the handle is released. A significant improvement in operational consistency results, with no impediment to motion or complexity of assembly created. 
     Accordingly, in an embodiment of the present invention, a gate latch is provided and includes a vertical latch assembly including a latch housing and a latch plate disposed centrally therein, the latch plate pivotally mounted to the latch housing by a pin, the latch assembly capable of passively receiving and locking a latch bar mounted to a gate, a latch operating assembly including a cylindrical body having a first end positioned in proximity to the latch assembly, and a second end, the cylindrical body including male threads at least on both ends to accept a first flange nut having matching female threads at the first end, and a second flange nut having matching female threads at the second end, a resilient linear member disposed linearly through the cylindrical body, the linear member fastened to a seat on the latch plate and fastened to a handle at the opposite end, and at least one spring disposed over the linear member, the spring retained in relaxed state within the cylindrical body by a first clamp and first metal washer strategically applied to the linear member at one end of the spring and by a second metal washer seated within the cylindrical body at the opposite end of the spring. 
     In one embodiment, the linear member is a plastic zip tie that connects to a zip tie receptacle fastened to the latch plate by a pin. In one embodiment, the vertical latch assembly mounts to the face of a gatepost and wherein the latch operating assembly is secured in a through hole drilled through the gatepost above the mounted latch assembly. In one embodiment, the linear member is a braided wire having a first fastening utility at one end for fastening the wire to the latch plate and a second fastening utility disposed at or near the opposite end for fastening the wire to the handle. In this embodiment, the second fastening utility is a second clamp clamped over the wire a strategic distance from the latch plate and fastened to the handle. 
     In an embodiment where the linear member is a plastic zip tie, the zip tie is inserted through a central opening in the handle and wherein the zip tie head seats in a recess provided on the face of the handle. In an embodiment where the linear member is a wire, the wire is inserted through a central opening in the handle and wherein the clamp seats in a recess provided on the face of the handle. 
     In one embodiment, the gate latch further includes a first rubber washer disposed between the first flange nut and the face of the gatepost, a second rubber washer disposed between the second flange nut and the opposite face of the gatepost, and a third rubber washer disposed between the second flange nut and the handle. 
     In one embodiment, the gate latch further includes a first end cap having a central opening placed there through for accepting the linear member, the first end cap for covering the first end of the cylindrical body, and a second end cap having a central opening placed there through for accepting the linear member, the second end cap for covering the second end of the cylindrical body. In a variation of this embodiment, the first and second end caps have female threads and are treaded onto the first and second ends of the cylindrical body. 
     In a preferred embodiment, the cylindrical body is cut to length to accommodate a specific thickness of the gatepost. In a variation of this embodiment, the linear member is cut to length to facilitate full opening of the latch. In one embodiment, the gate latch of claim  1  is installed on a wooden gatepost. In another embodiment, the gate latch is installed on a metal gatepost. 
     In one embodiment, the handle is fabricated from glow-in-the-dark plastic. In another embodiment, the handle includes a solar powered light emitting diode (LED) with batteries. In a variation of this embodiment, the solar power apparatus is contained in a cap fitted atop the gatepost. In another embodiment the handle is coated with a glow in the dark coating. In one embodiment, the gate latch further includes one or more additional linear members of varying but standard lengths. In one embodiment, the clamp used to retain the spring is a spring-loaded alligator type clamp. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
         FIG. 1  is an elevation view of a gate latch system according to an embodiment of the present invention in the latch-closed position. 
         FIG. 2  is an elevation view of the gate latch system of  FIG. 1  with the latch in the open position. 
         FIG. 3  is a front partial view of the vertical latch assembly of  FIG. 1  connected to the latch operating assembly of  FIG. 1 . 
         FIG. 4  is a sectioned and exploded view of the latch operating assembly of  FIG. 1   
         FIG. 5  is a process flow chart depicting steps for installing the gate latch system according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     The present invention provides a gate latch assembly and latch-operating component that makes operating a gate latch more consistent with less work on the part of the operator. The present invention will be described in enabling detail using the following examples, which may describe more than one relevant embodiment falling within the scope of the present invention. 
       FIG. 1  is an elevation view of a gate latch system  100  according to an embodiment of the present invention in the latch-closed position.  FIG. 2  is an elevation view of the gate latch system of  FIG. 1  with the latch in the open position. Referring now to  FIG. 1 , gate latch system  100  includes a modified version of vertical gate latch assembly  102 . Gate latch assembly  102  includes a gate latch housing  103  and a gate latch plate  104 . Gate latch housing  103  is a piece of sheet metal folded over on itself to form a housing that culminates in a mounting bracket having at least four openings provided there through for mounting purposes. Gate latch housing  103  is installed to the face surface of a gatepost  101  by wood screws  106  in this example. However other fasteners can be used. 
     Gate latch plate  104  is a piece of sheet metal formed into a latch capable of receiving a latch bar (not illustrated). Latch plate  104  is rotatably pinned within gate latch housing  103  using a pin or dowel  105 . Dowel  105  is a steel pin in one embodiment. However other rigid materials may be used in the manufacture of pin  105 . Gate latch assembly  102  is described as a vertical latch assembly because latch plate  104  assumes a vertical orientation in the assembly and opens and closes along a vertical plane orthogonal to the axis of pin  105 . 
     Gate latch system  100  includes a latch operating assembly  107 . Gate latch operating assembly is adapted to be installed through an opening provided by drilling or boring through the interior of gatepost  101  roughly in line with and orthogonal to the vertical gate latch assembly. In a preferred embodiment, gate latch operating assembly includes a cylindrical body such as a tubing or pipe  113 . The inside diameter of the through hole placed through gatepost  101  is held just larger that the outside diameter of cylindrical body  113  for a slidable fit. 
     Cylindrical body  113  has male threading provided at opposing ends to accommodate a first and second flange nut  114 . Flange nuts  114  have female threading matching the thread specification of the cylindrical tubing and are threaded over the cylindrical body at opposing ends. A washer may be utilized at either end between the gatepost surface and the flange nut. In a preferred embodiment, cylindrical body  113  is provided at such a length that it may be trimmed or cut to length to accommodate different thicknesses of gateposts. In this embodiment, the male threading on each side of the tube may be extended to about the center of the tube from both ends ensuring enough threading for installation of the flange nuts after cutting the tube to the appropriate length for installation. 
     Cylindrical body  113  is secured in rigid position within gatepost  101  by tightening down the flange nuts  114  over one or more washers until the body is rigidly secure within the post. The body should extend beyond the gatepost surface at both ends to accommodate further components that are attached to the assembly. For example, latch-operating assembly  107  includes a first and second cap  112 . Cap  112  has a central opening provided through the back wall for accepting a resilient linear member  108  such as a wire, or plastic zip tie. Cap  112  includes female threading about the inside surface thereof that is of sufficient depth to enable the cap to be threaded over the exposed end of cylindrical body  113  and over the flange nut hiding the flange nut from view. Cylindrical body  113  and caps  112  are fabricated of a polymer such as Polyvinyl Chloride (PVC) or some other whether and sun (UV)resistant material. Cylindrical body  113  and caps  112  could also be fabricated from any kind of metal such as brass, stainless steel etc. . . . . 
     Latch operating assembly  107  includes a handle  110 . Handle  110  may be molded of plastic or may be assembled (glued) from PVC components such as a short tube and opposing caps. Handle  110  may be hollow inside or it may be a solid piece of plastic. Handle  110  has an opening provided there through substantially in line with the longitudinal axis of tube  113 . The opening is sufficiently large to accommodate threading through of resilient linear member  108 . 
     Second cap  112  is threaded over tube  113  and flange nut  114  on the side of gatepost  101  opposite the latch side of the assembly. Linear member  108  is a zip tie, in one embodiment, consisting of a linear member capable of slidably locking to a zip tie receptacle such as the standard receptacle found at one end of a typical zip tie. The use of a zip tie in this example does not represent a limitation of the present invention as other types of linear members such as a string, cord, or wire might be used instead without departing from the spirit and scope of the present invention. The use of a zip tie in this example presents an opportunity to trim or cut the tie to a length suitable for fully closing and opening the latch plate in the latch assembly and an opportunity for a quick connection to the latch plate after trimming. Linear member  108  can be connected to latch  104  in any number of ways without departing from the scope of the invention. 
     In this example, linear member  108  is physically inserted through latch operating assembly  107  from the end supporting handle  110 . In an embodiment where the linear member is a zip tie, a zip tie seat or stop seat  111  is provided as a counter bore feature at the opening on handle facing away from the assembly. In another embodiment, linear member  108  may be fastened to handles  110  in some other fashion. Linear member  108  extends through the center of cylindrical body  113  and extends out from the assembly toward the latch plate of the gate latch assembly  102 . 
     Latch operating assembly  107  includes a steel spring  115 . Spring  115  is disposed over linear member  108 . Spring  115  may be a straight spring or a tapered spring without departing from the spirit and scope of the present invention. Spring  115  has an outside diameter that is smaller than the inside diameter of tubing  113  so that it may be retained within cylindrical body  113 . Spring  115  is retained within cylindrical body  113  using at least two washers  117  and  118 , the washers disposed over linear member  108  and on opposite sides of spring  115 . In one embodiment washer  118  is seated within tubing  113  to retain one end of spring  115 . In another embodiment tube  113  has a shoulder at one end to retain spring  115 . A stop clamp  116  having an internal opening slightly larger than the outside dimensioning of linear member  108  is provided to station spring  115  in a relaxed sate on linear member  108 . Clamp  116  is pressed down over linear member  108  after it is inserted onto linear member  108  and slid into position before clamping it in place to retain spring  115  in position. In one embodiment, a butterfly clamp or some other clamping device such as a spring loaded alligator type clamp might be used instead of clamp stop  116 . 
     The free end of linear member  108  is trimmed if required before attaching it to latch plate  104  on latch assembly  102 . An opening is provided at the top end of latch plate  104  to facilitate an interface for attachment of the linear member. In this case, a plastic zip tie seat  109  comprising a plastic tube formed with an orthogonal zip tie receptacle is attached to latch plate  104 . In this configuration, zip tie  108  may be trimmed to length if required, and then inserted into the receptacle of seat  109  to secure the zip tie to the latch plate. Other methods of attachment are also possible depending upon the nature of linear member  108 , however, the method of attachment depicted herein affords the ability to trim and reattach if needed. 
     Spring  115  is illustrated in a substantially decompressed or relaxed state in  FIG. 1  taking up a length A within cylindrical body  113 . The length of A shall be sufficient to force latch plate  104  into a closed position owing to the resilient nature of linear member  108 . Referring now to  FIG. 2 , handle  110  is depicted as pulled out from the gatepost in an act of opening the latch. When handle  110  is pulled out, spring  115  within cylindrical body  113 , compresses due to the movement of the linear member and the retained position of the spring within body  113 . Latch plate  104  is pulled up to near maximum height; at least enough to free a latch bar and open the gate. Latch operating assembly  107  may be easily disassembled requiring only a wrench to loosen the flange nuts. A user may replace or readjust the linear member when required. The compression force of spring  115  may also be easily readjusted by taking the assembly apart performing the adjustment and reassembling the cylindrical body. The linear member may be detached from latch plate  104  by removing the pin through seat  109  or by snipping the linear member at the latch plate. Washers  117  and  118  are metal washers in this example however; plastic washers may also be used instead. 
     In one embodiment, handle  110  is made from glow-in-the-dark plastic or painted with a glow-in-the-dark paint so that a user may readily see the door handle at night or in low light conditions. In one embodiment, a solar powered LED with a mini solar collector, may be provided on handle  110  or in close proximity on the gatepost so that the handle is lit up when the sun goes down. Such as solar power source may include a voltaic solar cell or panel installed on top of the gatepost such as in a special vinyl post cap housing a pair of rechargeable batteries and battery charging circuitry. Handle  110  could also have its own mini solar collector and battery contained within the handle  110  itself. Solar solutions above could also be applied to element  112 . 
       FIG. 3  is a front partial view of the vertical latch assembly of  FIG. 1  connected to the latch operating assembly of  FIG. 1 . In this front view, latch assembly  102  can be better visualized. Latch assembly  102  is mounted vertically onto the surface of a gatepost by screws  106 . Latch plate  104  rotates about pin  105 . In this example, latch plate  104  includes an offset thumb flap  302  formed thereon for facilitating easy manual lifting of the latch plate in the assembly. Receptacle  109  is pinned onto latch plate  104  using the provided opening and a steel dowel  300 . 
     Linear member  108 , in this case, a zip tie, is inserted into a zip tie receptacle on seat  109 . The receptacle enables insertion and lock of the linear member into the receptacle. The only visible part of the latch operating assembly from this side of gatepost  301  is cap  112 . Cap  112  is threaded over the cylindrical body on top of and covering flange nut  114  visible in broken boundary beneath the cap in this view. It should be noted herein that there may be a counter bore relief at both end of the hole drilled through the gatepost so that the depth and diameter of the counter bore encompasses the flange nut. In one embodiment the cap contains bell feature that covers the flange nut to the wood of the gatepost while both the flange nut and cap are threaded onto the same end of the tube. 
       FIG. 4  is a sectioned and exploded view of the latch operating assembly of  FIG. 1 . The latch operating assembly is installed in a gatepost  400 . In this case, a gatepost  400  has an overall thickness of C representing a larger post than previously illustrated. Post  400  may be a 6×8 or an 8×8 gatepost. Cylindrical body  113  can be cut to length to accommodate all standard gateposts. In this example, a rubber washer  401  is placed between handle  110  and cap  112 . Caps  112  are threaded onto body  113  over flange nuts  114  as described further above. In this example, rubber washers  402  are placed one each beneath the flange nuts against the wood surface of gatepost  400 . In one embodiment, cylindrical body  113  may be installed through a metal or plastic gatepost that is solid or substantially hollow. Flange nuts  114  secure the latch operating assembly in place regardless of the post material. 
     In one embodiment of the invention, handle  110  may also be a cap and may be threaded, in one embodiment, over cap  112  when not in use to prevent inadvertent opening of the gate. In another embodiment, a screw may be provided to secure handle  110  to cap  112  when not in use to prevent unintended opening of the gate. In still another embodiment, a wire lock may be routed through both handle  110  and cap  112  and then closed to lock when not in use. A key may be required to unlock the handle from the cap so regular use may continue. When a user pulls out the handle against spring tension the latch plate lifts up to release the latch bar. When the user closes the gate, the user maintains the pullout state of the handle keeping the latch plate open until the gate is closed and the latch bar is seated in the latch assembly. As the user lets go of the handle with the gate closed, the Latch plate is gently forced down over the latch bar effectively locking the gate. The force-down of the latch plate is in part due to the resiliency of the linear member. 
     In one embodiment of the present invention, the latch-operating assembly includes a spacer component in the form of a spacer ring with a slot cut through the cylinder wall and breaking out at both ends. This enables the spacer ring to be positioned over the linear member and between the handle and the cap when the handle is pulled out against the spring pressure. In this case, spring tension holds the spacer in place and the gate latch stays in the open position for times or events when a lot of traffic will go back and forth through the gate. There are many possibilities. 
       FIG. 5  is a process flow chart  500  depicting steps for installing the gate latch system according to an embodiment of the present invention. In this aspect of the process, it is assumed that the latch assembly, including the seat for the linear member, and latch bar plate are already installed and working properly before beginning installation of the latch operating assembly. At step  501 , a user drills a hole through the gatepost at a position above and orthogonal to the vertical latch assembly installed on the opposite face of the gatepost as depicted in  FIG. 3 . The drill size may vary according to the scale of the apparatus. For example, the cylindrical body may have a larger diameter and come with a stronger spring for more robust installations on larger gateposts or for metal gateposts. Alternatively, the diameter of the cylindrical body may be smaller and housing a smaller spring for light post/gate installations. 
     The user inserts the cylindrical tube into and through the hole at step  502 . In this step, a user may visually determine if the tube should be cut to accommodate the thickness of the gatepost. Assuming that the tube will be cut to length during installation, the user cuts the tube to length at step  503 . The tube may be cut with a suitable PVC pipe cutter or like instrument. At step  504 , the user may place washers, one per each end, over the inserted tube. The washers may be rubber washers, plastic washers, or washers made from some other material suitable for cushioning washers. It is noted herein that a properly cut and inserted tube will have substantially equal lengths thereof protruding past both surfaces of the gatepost. 
     At step  505 , the user may install flange nuts, one over each end, threading the nuts down to the surface of the gatepost at both ends to secure the installation. In one embodiment the flange nuts may seat at the bottom of counter bores placed in the openings so that they recede past the surface of the gatepost in the installation. However, this is not required to practice the present invention. At step  506 , the user determines if the installation is rigid and secure. If at step  506  the user determines that the installation is not secure, the process resolves back to step  505  until the flange nuts are adequately tightened against the face of the gatepost. 
     At step  505 , if the user determines that the installation is secure, then the user inserts the linear member, such as a zip tie strip through the handle, the washer (between cap and handle), and the cap at step  507 . At step  508 , the user loads the first retaining washer, the spring, and the second retaining washer onto the linear member. The first retaining washer may abut against the flange nut. At step  509 , the user loads the clamp over or on the linear member at a position so as to abut against the second washer and spring, but without unduly compressing the spring. The clamp may be pressed or collapsed over the linear member or some other clamping technique might be observed. 
     At step  510  users install the linear member or tie and spring assembly into the cylindrical body or tube. A step  511 , the user threads the cap over the tube end down to cover the flange nut. At step  512 , the user threads the free end of the linear member or tie through the remaining cap at the opposite end. At step  513 , the user threads the remaining cap over the remaining tube end down to the flange nut to cover the flange nut. At this point the installation of the operating assembly is complete accept for the connection to the latch plate. 
     At step  514 , the user may pull back on the handle against spring compression and at step  515  the user may lift the latch plate to the top position or maximum height in order to gauge the proper distance of tie to the seat on the latch plate. With the handle pulled back and the latch plate pulled up, the user gauges the distance required to properly attach the linear member to the latch plate at step  516 . At step  517 , the user makes a determination whether to cut the linear member before attaching it to the latch plate. 
     If the user determines to cut the linear member to a more appropriate length at step  517 , the user snips the linear member to the proper length at step  518 . In one embodiment, there may be more than one linear member provided of different lengths that are applicable to certain installations and post sizes. In such a case, the user may simply choose the correct length from a pool of linear members. If the user determines not to cut the linear member, then the process skips step  518  and moves to step  519 . At step  519  the user inserts the free end of the linear member into the seat connected to the latch plate. In the case of a zip tie, the user only need insert the tie end to engage the teeth on the seat to lock the member in place. 
     At step  520 , the user then releases the handle to relax the spring, which in turn urges the latch plate into the closed position. The process then ends for installation at step  521 . The user may now pull and release the handle to open and close the latch plate required to open and close the gate. 
     It will be apparent to one with skill in the art that the gate latch system of the invention may be provided using some or all of the mentioned features and components without departing from the spirit and scope of the present invention. It will also be apparent to the skilled artisan that the embodiments described above are specific examples of a single broader invention that may have greater scope than any of the singular descriptions taught. There may be many alterations made in the descriptions without departing from the spirit and scope of the present invention.

Technology Category: 4