Abstract:
A tool for removing nail fins from vinyl window frames comprising either a pneumatic wrench or an electric hand drill driving a tool having a slot into which cutter wheels project along with toothed rings above the cutter wheels. The toothed rings move the tool along the nail fin while the cutter wheels cut the nail fin from the frame.

Description:
BACKGROUND OF THE INVENTION 
     Vinyl window frames, when used in new construction, have one or two nail fins extending outward perpendicularly from the frame. When used in existing construction, however, the nail fins must be removed before installation. 
     I was watching an employee in the process of removing a nail fin from a vinyl window frame when the scoring knife slipped, and he cut his forearm, requiring a trip to the hospital emergency room to get his arm stitched. 
     Additionally, there are carpal tunnel problems due to heavy downward pressure on the scoring knife, which adds to the time loss to the employer and the employee. 
     Another alternative is to use a table saw to cut the fin off. The use of a table saw is a potential hazard, and always requires extra time to clean chips from the extrusions. 
     In removal of the nail fin by scoring, the worker has to score the fin at the frame, and push down and pull up on the fin to fatigue it to break it off. It takes a strong person to do this all day. 
     The nail fin removal tool I have developed eliminates accidental injuries from scoring knives. The necessity of scoring the fin adjacent to the frame body so that the fin can be worked back and forth to break it off is eliminated. 
     The nail fin removal tool procedure is: 
     1. Line up tool on fin. 
     2. Apply drive power. 
     3. Guide tool. 
     4. Take off fin. 
     The advantages of the nail fin removal tool are: 
     1. The tool eliminates knife cuts. 
     2. Use of the tool greatly reduces wrist fatigue. 
     3. Accidents will be avoided when this tool is used, and will save the employer and employee many hours of lost time and medical expenses. 
     BRIEF DESCRIPTION OF THE INVENTION 
     The nail fin removal tool may be driven by means of a pneumatic wrench, as in FIG., 1, or an electric hand drill, as in FIG. 7. As can be seen in FIGS. 2, 3 and 4, within the tool are two parallel shafts. The shaft driven by the pneumatic wrench has a gear near the driven end. That gear engages with a similar gear on the second shaft. At the opposite end of each shaft is a cutter wheel. As a part of the cutter wheel, but separated from the cutter, is a toothed ring. As can be seen in FIG. 2, the toothed rings are spaced apart a sufficient distance to allow the teeth to engage the nail fin, and move the tool along the length of the fin. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a first model of the tool driven by a pneumatic wrench in the act of removing a nail fin. 
     FIG. 2 is a cross-section of the first model of the tool. 
     FIG. 3 is an exploded view of the first model of the tool viewed from the driven end. 
     FIG. 4 is an exploded view of the first model of the tool viewed from the cutter end. 
     FIG. 5 is a view of the first model of the tool viewed from the cutter end and showing the attachment for the pneumatic wrench. 
     FIG. 6 is a view of the first model of the tool viewed from the driven end and showing the attachment for the pneumatic wrench. 
     FIG. 7 shows a second model of the tool driven by an electric hand drill in the act of removing a nail fin. 
     FIG. 8 is a cross-section of the second model of the tool. 
     FIG. 9 is an exploded view of the second model of the tool viewed from the driven end. 
     FIG. 10 is a view of the assembled second model of the tool viewed from the cutter end. 
     FIG. 11 is a view of the assembled second model of the tool viewed from the driven end. 
     FIG. 12 is an exploded view of a third model of the tool. 
     FIG. 13 is a view of the assembled third model of the tool viewed from the cutter end. 
     FIG. 14 is a view of the assembled third model of the tool viewed from the driven end. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows the first model of the tool 10 driven by pneumatic wrench 11. Wrench 11 is attached to tool 10 by circular split yoke 12, to which is welded bar 13. Bar 13 is screwed to tool 10. The tool 10 is in the act of removing nail fin 14. 
     Referring to FIGS. 3 and 4, the method of assembly is as follows. Cutter wheel 15 is placed at the end of shaft 18 and held in place by a set screw 17. Cutter wheel 16 is placed on shaft 19 and held in place by a set screw 17. The ends of shafts 18 and 19 are co-planar with the cutting edges of cutter wheels 15 and 16. Ball bearing 33 is pressed on to shaft 18, and ball bearing 21 is pressed on to shaft 19. Cutter wheel 15 assembly is then pressed in to recess 22 in cutter housing 20. Cutter wheel 16 assembly is then pressed in to recess 22 in cutter housing 20. Shaft 18 projects through opening 23 in cutter housing 20, and shaft 19 projects through opening 24. Ball bearing 25 is pressed onto shaft 18 and occupies opening 23. Ball bearing 26 is pressed on to shaft 19 and occupies opening 24. Gear 27 is placed on the end of shaft 18 and held in place by set screws 29. Gear 28 is placed on shaft 19 and is held in place by set screws 30. Gear lubricant is placed on gears 27 and 28. Gear housing 31 is placed over gears 27 and 28 and is screwed to cutter housing 20 by means of screws 32. Slot 36 is provided to accommodate the nail fin and to expose necessary portions of the cutter wheels and the toothed rings 35 which advance the tool. 
     The second model of the nail fin removal tool is illustrated in FIGS. 7-11. The tool 40 is being powered by an electric drill 41 which is attached to tool 40 by a split circular yoke 42 to which is welded an arm 43. Arm 43 is screwed to tool 40. Nail fin 44 is being removed. 
     Cutter wheel 45 is attached to the end of shaft 47 by means of set screws 46. Ball bearing 48 is then pressed on to shaft 47. Shaft 47 assembly is then placed into housing 48 with its end projecting through opening 49. Bearing 50 is then pressed on to shaft 47. Bearing 50 occupies opening 49. Drive member 51 is then placed on the end of shaft 47 and is held in place by set screws 51. Member 52 is an anvil that is screwed into housing 48. Cutter wheel 45 has a close clearance with anvil 52 enabling cutter wheel 45 to cut deeply into nail fin 44. Anvil 52 is mounted rotatably on screw 53. Slots 56 and 57 are provided to accommodate the nail fin and to expose the necessary portions of cutter wheel 45, anvil 52, and the toothed ring 58 which advances the tool. 
     The third model of the nail fin removal tool is illustrated in FIGS. 12-14. The drive shaft is 60, and the driven shafts are 61 and 62. Bearing 65 is pressed on to shaft 60. The assembly is then pressed into opening 70 of cutter housing 73. Cutter wheel 63 is mounted on shaft 61 and is held in place by set screw 68. Bearing 66 is then pressed on to shaft 61 and the assembly is pressed into opening 71 in cutter housing 73. Cutter wheel 64 is mounted on shaft 62 and is held in place by set screw 69. Bearing 67 is pressed on to shaft 62 and the assembly is pressed into opening 72 in cutter housing 73. Bearing 74 is pressed on to shaft 60. Bearing 75 is pressed on to shaft 61. Bearing 76 is pressed on to shaft 62. Bearings 74, 75 and 76 occupy recesses in cutter housing 73 (not shown). Driving gear 77 is attached to shaft 60 with set screws 80. Driven gear 78 is attached to shaft 61 by set screw 81, and driven gear 79 is attached to shaft 62 by set screw 82. After packing with gear lubricant, gear housing 83 is placed over gears 77, 78 and 79 and is screwed to cutter housing 73 with screws 84 (only one of which is shown). Slot 85 is provided to accommodate the nail fin and to expose the necessary portions of cutter wheels 63 and 64, and the toothed rings 86 which advance the tool. 
     There has been described above a hand-held self-propelled tool which will remove a nail fin from a vinyl window frame simply by aligning the tool and applying electric or pneumatic power. The use of hand-held knives is no longer necessary.