This invention relates generally to layout tools, and more particularly to so-called “squaring” tools for marking cut lines on workpieces.
There are several different types of layout tools that have been designed to assist carpenters in framing and construction of roof rafters, staircase stringers, spacing studs, marking rip lines, and the like. Carpenters often use framing squares for laying out staircase stringers and spacing studs. Perhaps the most famous tool for laying out roof rafters is the Swanson Speed Square offered by the Swanson Tool Co. of Frankfort, Ill. The speed square is shaped like a right-angle triangle with an enlarged lip or flange extending along one of the legs of the triangle.
The enlarged lip or flange of the speed square is a critical part of the speed square, for the speed square is positioned on a workpiece by pressing the speed square's lip against the workpiece straight edge. But the enlarged lip or flange makes the speed square, without an awkward accessory, unsuitable for laying out staircase stringers. Swanson Tool Co. offers a “Big 12 Speed Square” that combines an accessory that it refers to as a “layout bar” with a triangular speed square, for use in laying out staircase stringers. The layout bar, however, is not used to angularly align the speed square against a stringer. Rather, the layout bar simply adds a lip along the other “leg” of the right-angle triangle so that the speed square can be used to layout staircase stringers. Not only are two connectors required to connect the layout bar to the speed square, but also two separate “stop pegs” are required to configure the tool for laying out stringers. This particular product, in the inventor's opinion, is awkward, difficult, and time-consuming to use.
The inventor has developed an all-in-one combination layout tool that combines and extends the functions of a so-called “speed square” and a “framing square.” It is easy to use and configure for different purposes, including marking center lines for spacing studs, marking rip lines, and marking cut lines for roof rafters and staircase stringers. It is also easier to mark accurate and consistent cut lines with this new layout tool than with prior art devices.
The tool comprises a rectangular base plate, an elongate locator bar with a rounded pivot corner, and just two connectors to connect the locator bar to the base plate in a variety of configurations. The base plate includes multiple “pivot” points for pivotally connecting the locator bar, two strategically-placed arcuate slots for marking or making angle cuts, and two strategically placed parallel slots for configuring the tool to mark or make rip cuts. Angle markings are provided on two adjacent edges of the base plate, and 1/16-inch markings are provided on the opposite adjacent edges. The base plate is planar and has no enlarged flange or lip that would hinder its use in laying out staircase stringers.
The locator bar is far more useful than the so-called “layout bar” of the “Big 12 Speed Square.” For one thing, the locator bar can function by itself as a ruler, straight edge, or gauge. Second, the locator bar's “measuring edge” replaces the need for a “lip” on base plate. Either a rounded pivot corner, or the entire “measuring edge” of the locator bar is pressed against a workpiece straight edge in order to position the layout tool for marking or making cut lines. Third, the locator bar can be locked into a selected angular position for very accurate and stable positioning of the layout tool against a workpiece. When configured this way, the layout tool is so stable that it can be used directly as a saw guide - eliminating in many cases the need to mark a cut line. With the tool's locator bar locked into a fixed angular position with respect to the base plate, the tool can be placed against a workpiece while a circular saw is moved against an edge of the base plate, making an accurate angular cut. Fourth, the locator bar can be oriented to mark not only selected cut angles, but also staircase stringer “rise” and “run” cut lines. Fifth, the locator bar can be positioned parallel to the longitudinal edge of the base plate, for easy marking or cutting of “rip” lines. Sixth, the locator bar is longer than the either the width or length dimensions of the base plate. This allows the layout tool to be configured as either an 8-inch by 16-inch framing square or as a 12-inch by 16-inch framing square.
Furthermore, the rectangular shape of the base plate facilitates accurate angle markings and cut lines along four different edges, and more specifically, along two sets of parallel edges. As illustrated in the accompanying drawings, this configuration provides a number of advantages over prior art tools. One significant advantage is that it the tool does not have to be reconfigured to layout a staircase stringer. Based on the inventor's own experience, it dramatically reduces the time needed to layout staircase stringers—by as much as 90%. It also enables the tool to mark angle cuts from between 0 and 180 degrees, without flipping the tool.
Part of what makes the present invention so innovative and remarkable is its elegant simplicity. It comprises only a few different parts and is easy to use. But despite its simplicity, the present invention provides numerous advantages over more awkward prior art tools. Those of ordinary skill in the art will appreciate these and other improvements described further below in the detailed description and the accompanying drawings.
a through 8d illustrate the layout tool of
The elongate locator bar 50 measures 1 inch wide by 16 inches long by 3/16 inches thick. It has a latitudinal (i.e., minor-axis) alignment edge 52, a right latitudinal edge 53, a straight measuring edge 55 (also referred to as a “layout edge”), and a longitudinal (i.e., major-axis) alignment edge 59 opposite the measuring edge 55. Regularly-spaced English-unit distance markings 58, the smallest of which are 1/16th of an inch, are inscribed adjacent both the measuring edge 55 and the proximal longitudinal edge 59. The locator bar 50 includes an arrow 61 and the textual inscription 62 “measure edge” to assist users in the proper assembly and configuration of the layout tool 10.
The locator bar 50 includes a round pivot hole 51 located near the bar's latitudinal alignment edge 52 and centered on the ½-inch mark. The hole 51 is provided to receive a shaft connector 85 to pivotally attach the locator bar 50 to one of four holes 31-34 of the base plate 20. Accordingly, the hole 51 has a diameter slightly greater than the diameter of the shafts 86 of the connectors 85.
The locator bar 50 has four corners, all of which are right-angled except for rounded corner 54. Rounded corner 54 has a radius of ½ inch that extends in a clockwise direction from the midpoint of the latitudinal alignment edge 52 to the ½-inch mark on the measuring edge 55. When two connectors 85 secure the locator bar 50 to the rectangular base plate 20 as shown in
A first longitudinal slot 56 extends through the middle of the locator bar 50 from approximately from the 2-inch mark to the 10-inch mark. A second longitudinal slot 57 extends through the middle of the locator bar 50 from approximately from the 11½-inch mark to the 13½-inch mark. Both longitudinal slots 56 and 57 are provided to receive another shaft connector 85 to lock the locator bar 50, at a second point, to the base plate 20. Accordingly, both longitudinal slots 56 and 57 have a width slightly greater than the diameter of the shafts 86 of the connectors 85.
The base plate 20 measures 8 inches wide by 12 inches long by 3/16 inches thick. The base plate 20 has a front face 18, a back face 19, proximal left corner 21, a proximal right corner 22, a distal left corner 23, a distal right corner 24, a left latitudinal (i.e., minor-axis) edge 26, a right latitudinal edge 27, a proximal longitudinal (i.e., major-axis) edge 28, and a distal longitudinal edge 29.
Regularly-spaced English-unit distance markings, the smallest of which are 1/16th of an inch, are inscribed adjacent the left latitudinal edge 26 and the proximal longitudinal edge 28. This perpendicular set of distance markings serves many construction purposes, most especially the layout of a staircase stringer (illustrated in
Four round holes 31, 32, 33, and 34 are located near each of the corners 21-24 of the base plate 20. The holes 31, 32, 33, and 34, which are provided to receive a shaft connector 85 attaching the locator bar 50 to the base plate 20, serve as selectable pivot points for pivotally connecting the locator bar 20 to the base plate 20. Accordingly, the holes 31, 32, 33, and 34 have diameters slightly greater than the diameter of the shafts 86 of the connectors 85.
Angle markings, starting from 0 degrees at a point one inch above the proximal right corner 22 to about 31 degrees at the distal right corner 24, are inscribed along the right latitudinal edge 27. More angle markings, from about 31 degrees at the distal right corner 24 to 90 degrees at the distal left corner 23, are inscribed along the distal longitudinal edge 29. These angle markings are useful in marking cut lines when the layout tool 10 is pivoted about pivot point 31, as shown in FIGS. 2-5. Each of the angle markings is angularly oriented so that when the layout tool 10 is pivoted about pivot point 31 against the straight edge 115 of a workpiece 100, the angle marking corresponding to the selected pivot angle lines up with the workpiece edge 115.
Two elongated arcuate slots 36 and 37, each having common rafter slope markings 41 and hip-valley rafter slope markings 42, extend through the base plate 20. The markings represent the number of inches of rise per foot of run that an appropriately cut and assembled common rafter or hip-valley rafter is supposed to have. The markings facilitate orientations of the layout tool 10 to mark the appropriate rafter cuts. The arc of slot 37 has a 6-inch radius centered about 3 inches from the pivot point 31. The inside edge of slot 37 is concave with respect to pivot point 31 and is spaced from the pivot point 31 between about 6 inches at its closest point and about 9 inches at its farthest point.
The arc of slot 36 has a 9-inch radius. The inside edge of slot 36 is concave with respect to pivot point 33 and is spaced from the pivot point 33 between about 9 inches at its closest point and about 10 inches at its farthest point. The outside edge of slot 36 is convex with respect to and extends fairly close to, and along a long portion of, the proximal longitudinal edge 28 of the base plate 20. The orientation of slot 36 is deliberate, for, as illustrated in
The arcuate slots 36 and 37 each have a width slightly greater than the diameter of the shafts 86 of connectors 85, so that the shafts 86 can be inserted up through the slots 56 and 57 of the locator bar 50 and up through the slots 36 and 37 of the base plate 20, and then engaged by the flange nuts 90, to lock the locator bar 50, at a selected orientation, against the base plate 20.
The common rafter slope markings 41 and hip-valley rafter slope markings 42 are angularly oriented so that the locator bar 50, when affixed to the corresponding pivot point 31 or 33, can be pivoted so that it's measuring edge 55 lines up with a selected common rafter slope marking 41 or hip-valley rafter slope marking 42 (as shown in
The arc of slot 37 facilitates locking configurations of the locator bar 50 with respect to the base plate 20 (when anchored at hole 31) that range from about 3 degrees when the locator bar 50 is locked to the base plate 20 at the most proximal point available on the slot 37 to about 53 degrees when the locator bar 50 is locked to the base plate 20 at the most distal point available on the slot 37. The common rafter slope markings 41 of slot 37 extend from the value 1 to 12, which represents a range of rise/run slopes of between 1 inch of rise per foot of run to 12 inches of rise per foot of run. The hip-valley rafter slope markings 42 of slot 37 extend from 1 to 17, which represents a range of rise/run slopes of between 1 inch of rise per foot of run to 17 inches of rise per foot of run.
Slot 36 is provided for two purposes. The first purpose of slot 36 is to enable the locator bar 20 to be locked to the base plate 50 in a wide range of positions for laying out staircase stringers (see
A latitudinal L-slot 38 extends for about 4½ inches proximate and parallel to the left latitudinal edge 26. Another latitudinal straight slot 39 extends about 4½ inches proximate and parallel to the right latitudinal edge 27. The slots 38 and 39 each have a width slightly greater than the diameter of the shafts 86 of connectors 85, so that the shafts 86 can be inserted through the slots 56 and 57 of the locator bar 50 and through the slots 38 and 39 of the base plate 20, and then engaged by the flange nuts 90, to lock the locator bar 50 parallel to and at a selected distance from the proximal longitudinal edge 28 of the base plate 20. The slots 38 and 39 also have regularly spaced, coordinated alignment markings 43 and 44, the smallest of which are 1/16th of an inch, inscribed against their inside edges. These coordinated alignment markings 43 and 44 facilitate the parallel positioning of the locator bar 50 against the base plate 20, as shown in
Latitudinal slot 38 includes a longitudinal, approximately 1-inch extension 45 for staircase stringer configurations of the layout tool 10. The longitudinal extension 45 enables the locator bar 50 to be positioned so that its measuring edge 55 intersects both the 8-inch distance mark on the left latitudinal edge 26 and the 12-inch distance mark on the proximal longitudinal edge 28 of the base plate 20.
All of the markings shown on the front face 18 of the base plate 20 of
In this position, the proximal longitudinal edge 28 of the base plate 20 is aligned with the proximal longitudinal edge 59 of the locator bar 50. Also, the latitudinal alignment edge 52 of the locator bar 50 is aligned with a left latitudinal edge 26 of the base plate 20.
In
With the layout tool 10 so positioned on and against the workpiece 100, the left latitudinal edge 26 of the base plate 50 provides a guide for marking a line 125 or moving a saw at an angle corresponding to a selected common rafter marking 41 of the arcuate slot 37. Namely, the angle 110 between the left latitudinal edge 26 and a perpendicular 105 to the workpiece straight edge 115 is about 22.5 degrees, which equates very approximately to a rise of 5 inches per every foot of run. Likewise, the angle 111 between the proximal longitudinal edge 28 and the workpiece straight edge 115 is about 22.5 degrees.
The third cut line 127, unlike the first and second cut lines 125 and 126, extends at counterclockwise angle from the perpendicular 105. Because the rectangular configuration of the base plate 20 provides two guides, perpendicular to each other, for marking lines on a workpiece, the layout tool 10 facilitates the marking of cut lines from an angle of 0 to 180 degrees without the necessity of flipping the layout tool 10, as one would have to do to mark the same range of angles using a traditional triangular speed square. Eliminating the need to flip the tool 10 reduces confusion and errors and makes the process of marking and cutting lines easier, faster, and generally more accurate.
The third cut line 127 has an angle 113 to the perpendicular 105 equal to 90 degrees minus the second selected pivot angle 49. Viewed another way, the third cut line 127 has an angle 114 to the workpiece straight edge 115 that is equal to the second selected pivot angle 49.
In
In
In
To configure the layout tool 10 as shown in
In
Once the layout tool 10 is in the proper staircase stringer configuration, the tool 10 is positioned over the face of the stringer 200, with the measuring edge 55 of the locator bar 50 positioned against the straight edge 215 of the stringer 200. “Rise” and “run” pencil markings 225 and 226 are then quickly made against the left latitudinal edge 26 and the proximal longitudinal edge 28 of the base plate 20. After each set of rise and run pencil markings 225 and 226 is made, the layout tool 10 is quickly repositioned further down the stringer 200 to mark the next set of rise and run pencil markings 225 and 226.
a through 8d illustrate the layout tool 10 of
To mark the stringer cut level line 228, the layout tool 10 is simply translated from position “A” to the opposite side of the stringer 200, as illustrated in position “B,” with the proximal longitudinal edge 59 of the locator bar 50 lying against the opposite edge 216 of the stringer 200. The stringer cut level line 228 is then marked against the distal longitudinal edge 29 of the base plate 20. If the cut level line 228 needs to be extended, then the layout tool 10 is rotated counterclockwise 90 degrees and moved to the right edge 217 of the stringer 200, as illustrated in position “C,” with the proximal longitudinal edge 59 of the locator bar 50 lying against the right edge 217 of the stringer 200. The extension of the cut level line 228 is then marked against the right latitudinal edge 27 of the base plate 20.
To mark the stringer plumb cut line 227, the layout tool 10 is translated from position “C” to position “D,” this time with the measuring edge 55 of the locator bar 50 lying against the left edge 218 of the stringer 200. Alternatively, assuming that position “C” was not needed, the layout tool 10 is rotated counterclockwise 90 degrees from the position shown in position “A” or “B” and moved toward the left edge 218 of the stringer 200. Either way, the stringer plumb cut line 227 is then marked against the proximal longitudinal edge 28 of the base plate 20. If the stringer plumb cut line 227 needs to be extended, then the layout tool 10 can be translated (without rotation) from position “B” to position “E,” and the line 227 extended by marking against the right latitudinal edge 27 of the base plate 10.
Once the layout tool 10 is in the proper rip-line-marking configuration, the tool 10 is positioned over the face of the workpiece 100, with the measuring edge 55 of the locator bar 50 positioned against the straight edge 115 of the workpiece 100. Rip lines 155 are easily and quickly made by moving the pencil 120 along the proximal longitudinal edge 28 of the base plate 20, or by holding the pencil 120 against the edge 28 while sliding the base plate 20 along the workpiece 100.
The layout tool 10 can also be configured as two differently-dimensioned right-angle framing tools (often referred to in the art as a “framing square”).
Although not shown in the drawings, the locator bar 50 can be removed and separated from the base plate 20 and used as a gauge.
Although the foregoing specific details describe various embodiments of the invention, persons reasonably skilled in the art will recognize that various changes may be made in the details of the apparatus or method of this invention without departing from the spirit and scope of the invention as defined in the appended claims.
The present invention includes several independently meritorious inventive aspects and advantages. Unless compelled by the claim language itself, the claims should not be construed to be limited to structures that incorporate all of the inventive aspects, or enjoy all of the advantages, disclosed herein.
It is well established that the claims of the patent serve an important public notice function to potential competitors—enabling them to not only determine what is covered, but also what is not covered—by the patent. And a number of Federal Circuit decisions have emphasized the importance of discerning the patentee's intent—as expressed in the specification—in construing the claims of the patent.
It is my intent that the claims receive a liberal construction and be interpreted to uphold and not destroy the right of the inventor. It is my intent that the claim terms be construed in a charitable and common-sensical manner, in a manner that encompasses the embodiments disclosed in the specification and drawings without incorporating unrecited, unnecessary limitations. It is my intent that the claim terms be construed as broadly as practicable while preserving the validity of the claims. It is my intent that the claim terms be construed in a manner consistent with the context of the overall claim language and the specification, without importing extraneous limitations from the specification or other sources into the claims, and without confining the scope of the claims to the exact representations depicted in the specification or drawings. It is also my intent that not each and every term of the claim be systematically defined and rewritten. Claim terms and phrases should be construed only to the extent that it will provide helpful, clarifying guidance to the jury, or to the extent needed to resolve a legitimate, good faith dispute that is material to the questions of validity or infringement. Otherwise, simple claim terms and phrases should be presented to the jury without any potentially confusing and difficult-to-apply definitional construction.
It is also to be understood that the terminology employed in the Summary of the Invention and Detailed Description sections of this application is for the purpose of describing particular embodiments. Unless the context clearly demonstrates otherwise, is not intended to be limiting. In this specification and the appended claims, the singular forms “a,” “an” and “the” include plural references unless the context clearly dictates otherwise. Conversely, it is contemplated that the claims may be drafted to exclude any optional element or be further limited using exclusive terminology as “solely,” “only” and the like in connection with the recitation of claim elements or by use of a “negative” limitation. It is also contemplated that any optional feature of the inventive variations described herein may be set forth and claimed independently, or in combination with any one or more of the features described herein.
The headquarters building of the World Intellectual Property Organization bears the following inscription: “Human genius is the source of all works of art and invention; these works are the guarantee of a life worthy of me; it is the duty of the State to ensure with diligence the protection of the arts and inventions.” It is my intent that the claims of this patent be construed—and ultimately enforced, if necessary—in a manner worthy of this mandate.