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TECHNICAL FIELD 
   Marking of tiles for cutting. 
   BACKGROUND AND SUMMARY 
   Floor tiles are generally laid first in open areas of a floor and are then cut to fit gaps that occur along walls or around obstacles. Many tile marking devices have been proposed for marking tiles to be cut to fit into the resulting gaps. These generally measure a gap and then mark the measurement on a tile, proceeding one tile at a time. A manual method positions a whole tile upside down against a wall or obstruction so that the whole tile overlaps a laid tile, and then a mark is made along the laid tile for a portion of the whole tile to be cut away and turned right side up to fit into the gap. All of these systems mark one tile at a time using procedures that are inconvenient and slow. 
   Embodiments disclosed herein aim at a faster and more efficient way of marking tiles to fit accurately within gaps between laid tiles and walls or obstructions. Embodiments also cut tiles to be laid directly, rather than first drawing or scratching a profile and then cutting. Embodiments aim at simplicity, low cost, convenience, and accuracy in quickly accomplishing the marking of tiles so they can be cut to fit whatever gap remains to be filled with the pieces along walls or in corners. 
   The inventive system as illustrated by embodiments disclosed herein begins by positioning whole tiles on top of laid tiles, either individually or along rows of laid tiles. In doing so, embodiments apply to tiles of vinyl, ceramic, and other materials. A marking device having a probe and a marking element separated from the probe by a tile width is moved along a single tile or preferably along a whole row of tile. Marking element here encompasses drawing elements, such as pens, markers, pencils, paintbrushes, and chalk, scratching elements, such as knives and abrasive elements, and cutting elements, such as saws, lasers, and other tools used for cutting tile. As the probe follows a wall or obstruction, the marking element, which is spaced a tile width away from the probe, marks the tile or tiles along a line parallel with and spaced from the wall or obstruction. The marked tiles can then be cut along the marked line, and the cut off pieces will fit accurately into the space between the laid tiles and the wall or obstruction. Alternatively, where the marking element is a cutting element, it cuts the tile parallel with and spaced from the wall or obstruction so that the cut tile will fit into the space between the laid tiles and the wall or obstruction. 
   A preferred way of accomplishing this is with a base that includes a fence that can guide along the edges of laid tiles and the superposed tiles. The base also includes a spring that lightly presses the probe away from the fence to contact and stay engaged with a wall or obstruction as the base moves along, the superposed whole tiles are restrained by the fence from moving toward the wall or obstruction, and a board or straight edge can be laid along the edge of the superposed tiles opposite the wall to keep the superposed tiles from moving as the base slides along the tile edges. The marking tool can be moved by hand, or a handle extending upward from the base can facilitate the movement along the tile row. The result is then a whole row of tiles accurately marked to fit a gap between laid tiles and a wall or obstruction. The tile marking accomplished this way can automatically follow variations in gap dimensions between the laid tiles and a wall or obstruction. 
   A special arrangement allows the marking device to mark a corner tile so that it can fit into a corner gap between two walls or between a wall and an obstruction. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIGS. 1-3  are partially schematic side elevations of a preferred embodiment of the inventive tile marker deployed to mark tiles for different dimensions of gaps between a laid tile row and a wall. 
       FIG. 4  is a schematic plan view showing how a spring within a base biases a probe and marker rod. 
       FIG. 5  is a schematic plan view similar to the view of  FIG. 4  showing a transverse probe arm clampable to the main probe for corner marking. 
       FIGS. 6 and 7  show how rows of tiles can be marked to approach a corner. 
       FIGS. 8 and 9  show how a corner tile can be marked to fit into a corner gap where two tile rows intersect. 
       FIG. 10  is a schematic side elevation showing how a handle can be extended above a marking base to facilitate tile marking allowing the user to stand while operating the device. 
       FIG. 11  is a schematic plan view similar to the views of  FIGS. 4 and 5  showing a transverse probe arm attachable to the main probe for corner marking and extending in an alternate direction. 
   

   DESCRIPTION 
     FIGS. 1-3  schematically show how a simplified preferred embodiment  25  of the inventive marking device can be used for marking different dimensions of gaps between a laid tile  16  on floor  15  and a wall or obstacle  20 . Tile  17  to be marked is superposed over laid tile  16 , and a fence  27  of base  26  guides along the edges of tiles  16  and  17 . This allows base  26  and fence  27  to move along a whole row of laid tiles  16  and superposed tiles  17  while marking a line on or cutting superposed tiles  17 . To facilitate movement of the base  26 , rolling elements, such as wheels, ball bearings, or the like, can be mounted on the base  26  for engagement with a surface beneath the base  26 , such as a laid tile  17 . 
   Fence  27  keeps tile  17  from moving toward wall  20 . This is because fence  27  also guides on laid tile  16  and thus prevents superposed tile  17  from moving past the edge of laid tile  16 . A board or straight edge  18  can be positioned against the rear edge of a superposed tile  17 , such as shown in  FIG. 1 , so that board  18  can run along a row of superposed tiles  17  and help stabilize them against movement away from wall  20  while base  26  and fence  27  slide along the tile edges. 
   A marking rod  30  is mounted on base  26  to move back and forth under a bias preferably provided by a spring  40 , alternative embodiments of which are shown in  FIGS. 1 and 4 . Different forms of springs can be arranged to accomplish this, and many different connections are possible for different source of springs. The rod  30  includes a probe  31  arranged near a forward end and a marking element  35  arranged near a rear end. The bias of spring  40 , however attached to marking rod  30 , urges probe  31  gently against wall or obstruction  20  as base  26  and fence  27  move along a tile edge or row of tile edges while marking element  35  marks a line on a superposed tile  17 . 
   The distance between a tip of probe  31  and marking element  35  mounted on rod  30  is preferably equal to a width of tiles  16  and  17 . With fence  27  engaging tile edges  16  and  17  and probe  31  engaging wall  20 , marking element  35  is then positioned to mark off a dimension on superposed tile  17  equal to the gap distance between laid tiles  16  and wall  20 . When tile  17  is so marked, the piece of tile  17  between marking element  35  and board  18  fits in the gap between laid tile  16  and wall  20 . The width of the gap and the corresponding width of the piece to be cut from a superposed tile  17  can vary as marker  25  proceeds along a row of tiles. 
   Marking element  35  can be any convenient marking instrument, such as a ballpoint pen, felt tip marking pen, pencil, chalk, saw, or knife. As used herein, “marking” includes drawing, as with a pen, pencil, chalk, marker, or other drawing implement, scratching, as with a knife, abrasive element, or other scratching tool, and cutting, as with a tile saw, knife, laser, torch, or other cutting implement. Selection of an appropriate marking element  35  is based on low cost and reliability in marking a line that can be followed to cut a tile or cutting the tile outright. Probe  31  can have a ball bearing or wheel arranged to roll smoothly with reduced friction along a wall or obstruction. In alternative embodiments, a cutting device can be used marking element  35  to simply cut the tile to be marked rather than first marking, then cutting the tile. Thus, marking element  35  can take the form of a saw, laser, torch, heating element, or other device that can cut tile. 
     FIG. 2  schematically illustrates the same marking device  25  as illustrated in  FIG. 1 , but positioned to mark a narrower piece of superposed tile  17  fitting a narrower gap between laid tile  16  and wall  20 .  FIG. 3  schematically illustrates the same tile marking device  25  as illustrated in  FIGS. 1 and 2 , but positioned to mark for the wider gap between laid tile  16  and wall  20 . 
   As also illustrated in  FIG. 3 , a notch in a bottom of body  26  serves as a rear fence  28  that can be used to guide along the tile edges instead of front fence  27 . Motion of probe  31  and marker arm  35  back and forth within base  26  is limited by the width of base  26 , so that rear fence  28  provides an alternative to front fence  27 . Fence  28  can then be used, as shown in  FIG. 3 , when a wide gap exists between laid tile  16  and wall or obstruction  20 . 
   A front vertical notch  23 , as shown in  FIG. 2 , provides a recess to accommodate probe  31  when measuring a narrow gap, and a rear vertical notch  24 , as shown in  FIG. 3 , provides a recess to accommodate marking element  35  when measuring a wide gap. Altogether, base  26  is preferably dimensioned to enable marking of both the smallest and largest possible cuts from superposed tile  17  and any dimension of cut in between these. 
     FIGS. 5 ,  8 , and  9  schematically show a corner probe  50  clamped to marker arm  30  to aid in corner marking. Probe arm  50  extends from arm  30  by one tile width, just as the distance between probe  31  and marking element  35  equals one tile width. Referring to  FIGS. 8 and 9 , probe arm  50  allows tile marking tool  25  to guide along an adjacent wall while marking a corner tile  17 C for a cut shaped to fit a corner gap, as explained below. While the probe arm  50  is shown extending from the marking arm toward the opposite side of the base  26 , the probe arm  50  can instead be mounted to project from the marking arm away from the base, as seen, for example, in  FIG. 11 . This alternative arrangement can allow for more flexibility in marking corners in that the base  26  does not interfere with the movement of the marking arm toward a corner wall in some circumstances. 
     FIGS. 6 and 7  show how rows of tiles  17  can be marked to approach a corner  21  between two walls  20 A and  20 B.  FIG. 7  shows how a row of superposed tiles  17  can be positioned on top of laid tiles (not shown) and possibly stabilized by a board  18  as the tile row extends along wall  20 A approaching corner  21 . The tiles marked with line  36  can then be cut to fit into the gap between the tile row and wall  20 A. 
   In a similar way, tool  25  can move along tiles  17  in a direction parallel to wall  20 B while marking line  37 . For this step, the corner-most tile  17 C is replaced to form a new tile row extending along wall  20 B. Then, as illustrated in  FIGS. 6 and 7 , tile pieces cut along line  37  can then fit the gap between tiles  17  and wall  20 B. 
   Once the tiles are marked with lines  36  and  37  and/or are then cut to form pieces that fit the gaps along walls  20 A and  20 B, what remains is an empty corner gap to be marked for a filling tile piece as shown in  FIGS. 8 and 9 . This requires use of an additional corner tile  17 C and the use of corner probe  50 , also illustrated in  FIGS. 5 and 11 . Marking tool  25 , with corner probe  50  attached, is moved along tile  17 C to approach corner  21  between walls  20 A and  20 B. Corner probe  50  engages wall  20 B and stops probe and marking arm  30  so that marking element  35  stops one tile width short of corner  21 . Then marking tool  25  is slid along a top face of tile  17 C while holding probe  50  against wall  20 B so as to mark line  37  parallel with wall  20 B. A corner piece cut from tile  17 C along lines  36  and  37  then fits into the tile gap at corner  21 . Fence  27  is preferably vertically adjustable so it can be raised to facilitate movement of body  26  over the top surface of tile  17 C during marking of line  37 . In embodiments in which the marking element  35  directly cuts the corner tile  17 C, the corner piece is ready to be placed in the gap as soon as the user has finished with the marking tool  25 . 
   Since marking tool  25  can quickly mark or cut along a whole row of tiles, it is convenient to have a handle  55  extending upward from body  26  so that an operator, after laying a row of superposed tiles  17 , can slide body  26  along the tile edges by using handle  55  to mark a whole row of tiles in a few seconds. This saves bending over and crawling about on hands and knees. Rolling elements  29 , such as wheels or ball bearings, placed in the base can further ease use of the marking tool  25  as seen, for example, in  FIG. 3 . 
   It will be appreciated that various of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. It will also be appreciated that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.

Summary:
A tile marking tool uses a probe mounted on a biased marking arm to engage and follow a contour of an obstruction, such as a wall, cabinet, or heat vent, adjacent which floor tile must be installed. As the tool is moved along the wall, a marking element on the other end of the marking arm marks or cuts the contour of the obstruction on a tile or tiles to be laid, facilitating cutting and/or placement of the tile in such a way as to fit well against the obstruction. Embodiments include a corner marking arrangement for marking tiles to be laid in reentrant corners. The corner marking arrangement includes a corner arm attachable to and orthogonal to the marking arm so that the tool is used in usual fashion as it approaches the reentrant corner.