This invention relates generally to flooring tools, and in particular to vinyl composition tile cutters.
In the floor covering trade, vinyl composition tile is a common flooring for commercial applications. Vinyl composition tile is often referred to as VCT (or VCT tile), a common example being Armstrong Excelon VCT Tile. Such tile has the benefits of low materials cost, low labor cost to install, durability, and ease of cleaning. VCT tile is often installed in large rooms such as classrooms, cafeterias, supermarkets, and other commercial spaces. The VCT tile can be easily adhered directly to the concrete floors commonly found in such buildings, using low cost adhesive. The labor cost to install VCT tile is lower than ceramic tile because the tiles are precisely formed to abut each other without the need for grouting at the joints.
As shown in
VCT tile is cut to desired lengths in one of the following methods: VCT tile can be cut by hand by marking the desired cut on the tile with a penciled line, then scoring the line with a razor knife guided by a straight edge. After scoring, the tile can be broken along the score line by bending the tile by hand on both sides of the score line.
Alternatively, professional VCT tile cutters have been developed, such as the present day Crain No. 001 Model “A” Tile Cutter. These prior art VCT tile cutters can cut across the entire width of a VCT tile rapidly with inexpensive, low carbon steel blades, using pressure from the stroke of a crankshaft mechanism, as will be described below.
An assembled prior art VCT tile cutter 10000 is shown in
The crankshaft and blade carrier subassembly 11000 is assembled to base 10100 by first fastening the top blade 12000 onto blade carrier 12050. Top blade 12000 is fastened to blade carrier 12050 in blade carrier relief 12051 with four bolts 12055. Top blade 12000 will be referred to as the movable blade of VCT tile cutter 10000 because it moves vertically in the cutting action of the tool. Top blade 12000 has a straight bottom edge 12005 with a square left end 12007 and a square right end 12009.
Once the blade and blade carrier are assembled, a left guide 12100 is connected to base 10100 with a screw 12105. A left end of blade carrier 12050 inserts into a slot 12110 of left guide 12100. Above the left end of blade carrier 12050, a left bearing block 12120 is also inserted into slot 12110 of left guide 12100.
Crankshaft 13000 includes camshaft 13010, lever 13020, left ball bearing 13030, right ball bearing 13035, left pin 13040, and right pin 13045. Left pin 13040 and right pin 13045 insert within eccentric holes in camshaft 13010 (such as right eccentric hole 13011). Left pin 13040 inserts within slot 12110 of left guide 12100 beneath left bearing block 12120.
Right guide 12150 is positioned on a free right end of blade carrier 12050 within slot 12160. Next pin 13045 of crankshaft 13000 is inserted into slot 12160, followed by right bearing block 12125, which rests on top of pin 13045. Right guide 12150 can then be fastened to base 10100 with fastener 12155.
Left ball bearing 13030 has a flange 13031, and right ball bearing 13035 has a flange 13036. Flange 13031 of left ball bearing 13030 seats in left slot 12052 in the top surface of blade carrier 12050. Flange 13036 of right ball bearing 13035 seats in right slot 12054. The insertion of the flanges of the ball bearings into the slots on the top surface of blade carrier 12050 controls the eccentric motion of left ball bearing 13030 and right ball bearing 13035 as they pressure the top of blade carrier 12050 in the cutting action of the tool. This eccentric motion will be described below along with the discussion of the cutting action of the tool.
Left guide 12100 has a hole 12107 in the bottom of slot 12110, and right guide 12150 has a similar hole (not shown). Blade carrier 12050 has corresponding left and right holes on its bottom side (not shown) which align with the holes in the bottom of left guide 12100 and right guide 12150. Left coil spring 14005 and right coil spring 14007 insert through the holes in the bottom of the left guide 12100 and right guide 12150 and extend up into the left and right holes (not shown) of blade carrier 12050. Two pairs of pan head screws 14011, 14013 additionally fasten left guide 12100 and right guide 12150 to base 10100 through back side holes (not shown) in base 10100. The inner of each pair of pan head screws 14011, 14013 passes directly underneath the hole in the bottom of the left guide 12100 and right guide 12150, each creating a footing for left coil spring 14005 and right coil spring 14007. Left coil spring 14005 and right coil spring 14007 pressure blade carrier 12050 upward within slots 12110, 12160 in left guide 12100 and right guide 12150
Because the blade carrier 12050 is constantly pressured upwards by left coil spring 14005 and right coil spring 14007, it causes lever 13020 to rotate backwards (clockwise). A leg 13025 formed by an extension of lever 13020 through the back of camshaft 13010 contacts the back of blade carrier 12050. This creates a stop for lever 13020 at a vertical position. At the stop, the vertical position of lever 13020 also corresponds to a high point or starting position of top blade 12000.
Left set screw 15011 and right set screw 15013 work against left coil spring 14005 and right coil spring 14007 to set a starting height and shear angle of the movable upper blade 12000. Left set screw 15011 and right set screw 15013 bear on left bearing block 12120 and right bearing block 12125. Turning left set screw 15011 or right set screw 15013 causes left pin 13040 or right pin 13045 of crankshaft 13000 to move up or move down.
If both left set screw 15011 and right set screw 15013 are turned by equal amounts, blade carrier 12050 and top blade 12000 are moved straight up or down. However, for ease of cutting, a “shear angle” in the cutting action of top blade 12000 is preferred. A shear angle is an orientation of the top blade 12000 where, in its starting position, the space between top blade 12000 and bottom blade 10200 on the right side is 2-3 times the space on the left side. A shear angle on the blade causes the blade to cut only a small portion of the tile as lever 13020 is being turned. This reduces the force necessary to be applied on lever 13020 as the tile is being cut. To produce the shear angle, left set screw 15011 only can be turned such that the gap on the opposite right side is a preferred 2-3 times that on the left side.
Left guide 12100 is fitted with left ball caster 12115, and right guide 12150 is fitted with right ball caster 12165. Left ball caster 12115 and right ball caster 12165 facilitate lateral movement of the tile cutter when used with the floor guide 10210 (discussed below).
To make a cut, a user marks a line the full length across a tile, and places it on bed surface 10105 of base 10100. The user positions a right edge of the tile against a fence 10110. The fence 10110 squares the tile to top blade 12000 and bottom blade 10200. The user aligns the marked line with the line of top blade 12000 and pulls lever 13020 downward. This causes camshaft 13010 to be turned. The eccentric positioning of left pin 13040 and right pin 13045 rotates left ball bearing 13030 and right ball bearing 13035 forward and down, causing blade carrier 12050 to be pressured downwards. This causes the movable top blade 12000 to pressure the tile against fixed bottom blade 10200, thereby shearing the tile. Afterwards, the user releases lever 13020, and it returns to a vertical position. In the same motion, top blade 12000 also returns to a starting position.
A tile guide 15000 can be fastened to fence 10110 with thumbscrew 15005 to make multiple cuts of a fixed width. A floor guide 10210 provides an alternative automatic measuring system. Floor guide 10210 forms a vertically adjustable lip which can work as a stop below base 10100 capable of positioning the blades of the cutter in line with the edge of the last full field tile. When floor guide 10210 is used, a full tile is placed on the bed surface 10105 and slid underneath top blade 12000 until it abuts a wall. With the cutter in this position, the blades will automatically cut a fill tile for the proper width at that particular location.
The assembled prior art VCT tile cutter 10000 is shown in
Prior art VCT tile cutter 10000 is mainly useful to make straight cuts across an entire width of a tile, as needed to cut fill tile needed along straight walls. However, wall surfaces form many other shapes. One example is the shape of outside corners. In such case, as shown in
Another example of a situation where partial cuts in the VCT tile are needed is for “U-shaped” cutout shown in
To make the partial cuts shown in
However, VCT tile can be brittle, particularly when it is held in storage for an abnormally long period of time, or whenever it is being installed in cold weather. In such cases, the VCT tile cracks often cracks unpredictably beyond the score lines. In such cases, the flooring installer often has to pre-heat the tile with a powerful heat gun. The preheating process, often to referred to as a “hot cut” in the trade, adds additional labor cost.
In general, the labor involved in cutting tiles to fit corners areas, doorways, and other areas can be one of the more costly aspects of the installation. Most of the cuts required to fit tiles in these areas involve partial cuts in the VCT tile, but the prior art VCT tile cutter cannot make such cuts.
A VCT tile cutter that could make partial cuts in the VCT tile could speed up the process of making rectangular cutouts, “U-shaped” cutouts, or other cutouts requiring partial cuts in the tile. A VCT tile cutter that could make partial cuts in the VCT tile, while still being able to make the straight cuts across the entire tile as required at walls, would have greater utility, and could help reduce labor cost.
Embodiments of the invention comprise a VCT tile cutter with a movable top blade and a fixed bottom blade that shears a tile with a crankshaft mechanism. In addition, the cutter includes a blade carrier enabling the top blade to be slid horizontally in relation to the fixed position of the bottom blade beneath it.
In one embodiment, the blade carrier component includes an added slot. The top blade includes an added slideable member insertable in the slot. The slideable member slides within the slot, enabling the top blade to be slid horizontally (i.e., in a direction transverse to the cutting direction that is generally parallel to a cutting edge of the top blade) while being fixed in the direction of cutting.
In another embodiment, a blade carrier assembly comprises several components, including a first blade carrier component and a second blade carrier block component. The blade carrier component is slideably mounted to a fixed, blade carrier block component. A top blade is fixedly attached to the blade carrier component. However, the top blade can be slid horizontally along with the slideable blade carrier component.
With either of the embodiments, an outer edge of a top blade can be slid horizontally and positioned over a point in the tile which corresponds to the end point of a desired partial cut in the tile. The lever is activated and the blade will create a partial cut in the tile from the perimeter of the tile to a point in the center of the tile corresponding to the location of the end of the movable blade.
Embodiments of the invention additionally include faceted blade shapes enhancing the capability of the cutter to perform partial cuts in the tile. In one embodiment, the blade has a straight edge in a center area, similar to that of the prior art top blade, but additionally includes one or more relieved edges at either end of the blade. These partially relieved edges at the end of the blade produce a small scored area at the end of partial cut in the tile, corresponding to the relieved area at the end of the blade. This scored area can be broken after the cutting operation with light hand pressure. This prevents the undesirable cracking created by the prior art square-end top blades (such as top blade 12000 of
Alternatively, the top blade may be completely relieved from a point in the center of the blade, all the way out to left and right ends of the blade. Such a completely relieved blade is capable of cutting a tile from a point in the center of the tile outward to the perimeter of the tile. Such a blade can make the center cut of a “U-shaped” cutout (cut 32035 of “U-shaped” cutout 32005 in
The figures depict various embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.
As shown in
The blade carrier 22050 of VCT Tile Cutter 20000 includes an added slot 22057 in the area of the blade carrier relief 22051. The prior art VCT Tile Cutter 10000 of
The top blade 22000 includes an added slideable member 22010 attached with four screws 22020 to the back side of top blade 22000. Slideable member 22010 has a rectangular profile that is insertable within slot 22057 of blade carrier 22050 and slideable within slot 22057.
As shown in
As shown in
In the embodiment of
Conversely, the slideable member itself may be formed in other profiles, such as a “T-shape”. A “T-shaped” profile for the slideable member would require a corresponding “T-shaped” cutout (slot) in the blade carrier. Such would hold the blade on the blade carrier without the need for cover 22060.
However, a rectangular shape for the slot 22057 is preferred because it can be formed with conventional milling cutters. Furthermore, a corresponding rectangular profile for slideable member 22010 is preferred because it can be formed inexpensively as a sheet metal stamping. Cover 22060 is also a rectangular shape that can be formed inexpensively as a sheet metal stamping.
Furthermore, the slideable member may be formed from several pieces of material which are spaced apart, rather than a single lengthy piece of material such as the slideable member 22010 (
As shown in
The embodiment of
If the VCT tile is unusually brittle, the square corners at left end 22005 and right end 22007 on top blade 22000 (
As shown in
At any area beneath the straight central edge 25030, top blade 25000 will tend to cut the VCT tile all the way through. However, along the left relieved area 25035 or right relieved area 25037, top blade 25000 will tend to score or partially cut the VCT tile rather than cut all the way through. When the tile is removed from the cutter, any small scored areas that remain can be safely snapped by hand pressure. This prevents the undesirable cracking which can sometimes occur beyond the end of a partial cut in a VCT tile when straight blade 22000 (
As shown in
Top blade 22000 of
As shown in
The fully relieved top blade 26000, with its long left relieved area 26035 and right relieved area 26037 from center 26030, can cut the VCT tile from a point in the center of the tile outward. As shown in
Another embodiment including an alternative blade carrier comprising several components is shown in
In
As shown in
Another embodiment of the top blade facilitating partial cuts in a VCT tile is shown in
In another alternative, the top blade includes a slot, and the blade carrier includes features such as pins or bosses insertable into the slot in the top blade, such that the top blade is slideable on the features of the blade carrier.
In another alternative, the top blade includes a slot or a relief, and the blade carrier, or the cover attachable to the blade carrier, includes a feature such as a boss or a rib insertable into the slot or relief of the top blade, such that the slot or relief on the top blade is slideable on the boss or rib on the blade carrier, or the cover.
The foregoing description of the embodiments of the invention has been presented for the purpose of illustration; it is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Persons skilled in the relevant art can appreciate that many modifications and variations are possible in light of the above disclosure. For example, although discussed in terms of a cutter for VCT tiles, embodiments of the cutter may be designed for other types of materials that are relatively soft, such as cork or rubber, as opposed to hard tiles such as ceramic.
Finally, the language used in the specification has been principally selected for readability and instructional purposes, and it may not have been selected to delineate or circumscribe the inventive subject matter. It is therefore intended that the scope of the invention be limited not by this detailed description, but rather by any claims that issue on an application based hereon. Accordingly, the disclosure of the embodiments of the invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.
This application claims the benefit of U.S. Provisional Application No. 61/276,403, filed Sep. 11, 2009, which is incorporated by reference in its entirety.
Number | Date | Country | |
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61276403 | Sep 2009 | US |