Patent Publication Number: US-4481846-A

Title: Overhead fence assembly

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates generally to a fence assembly used in conjunction with a power saw which guides the stock through the saw. 
     When passing a piece of work through a tablesaw it is necessary that the stock be properly guided to ensure an accurate and straight cut. Most tablesaws are provided with an adjustable fence to guide the work through the saw. The present invention is designed to be used in conjunction with a conventional fence on a tablesaw so that work may be more accurately and safely guided through the saw. 
     The broad concept of an adjustable saw fence for a tablesaw is well known in the prior art. The following patents reflect the state of the art of which applicant is aware insofar as the appear to be germane to the patent process: U.S. Pat. Nos. 2,435,382 Caskey, 3,348,591 Carrasco, 2,764,190 Howard, 3,392,761 Klein, 3,192,814 Zimmerman, 4,002,329 Petrowski. 
     Of the references cited it would appear that the patent to Carrasco is significant since he teaches the use of a saw guide assembly in which a channel portion 7 is adapted to overlie a guide strip 3, and remain fastened thereto by means of a clamp 18, 20 (FIG. 2). In addition, the plate 9 is adapted to swing, as shown in that figure about hinge 12 to facilitate deployment of the device. The instant invention is distinguished from this and the remaining references in that it is capable of vertical adjustment so that the fence member can engage the work itself or be guided by a template affixed to the top of the work which guides the saw blade as the work passes through the saw. Furthermore, the instant invention is hinged so that the fence can be swung out of the way and the conventional tablesaw fence employed instead. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     It is a primary object of the present invention to provide a novel overhead fence assembly to be used with a powered table saw which is vertically adjustable so that it can guide the work through the saw directly by engagement therewith, or be used in conjunction with a template affixed to a top surface of the work product. 
     Another object of this invention is to provide a novel overhead fence assembly to be used in conjunction with a power saw which is hinged so that it can be folded up away from the saw blade area when not in use. 
     A further object of this invention is to provide a novel overhead fence assembly for use in conjunction with a power saw which can be adjusted for either left or righthanded use by simply reversing the fence to the other side of the blade. 
     Still another object of this invention is to provide a novel overhead fence assembly for use in conjunction with a power saw which minimizes scrap and waste and maximizes the usage of material that is truer to dimension by allowing a carpenter to effectively trim bowed, crowned, or crooked shaped wood that would formerly be scrapped. 
     A still further object of the present invention is to provide a novel overhead fence assembly for use with a power saw which also acts as a guard against the power saw blade because the saw cuts just underneath the fence support edge in an unexposed position. 
     The objects stated above and other related objects are accomplished by the provision of a vertically adjustable saw fence which can guide the work product directly through the saw or engage a template fixed to a top surface of the work product which allows crooked stock to be adequately trimmed and dimensioned for use as a component. Two hinged brackets adjustably deployed on a conventional fence are used in conjunction with two threaded shafts which allow the fence support to be vertically adjusted in relation to the work product. 
     Still further objects and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawing figures. 
    
    
     DESCRIPTION OF THE DRAWING FIGURES 
     FIG. 1 is a perspective view of the instant apparatus as it would be applied to a conventional type tablesaw. 
     FIG. 2 is a sectional view taken along lines 2--2 of FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now the drawings in detail wherein like reference numerals represent like parts throughout the several figures, reference numeral 10 in FIG. 1 refers generally to the device according to the instant application. 
     In FIG. 1, T is a flat table of a conventional tablesaw, B is a blade that extends through the table T, and F is a conventional type tablesaw fence. The overhead fence device 10 is affixed to the conventional fence F by two U-shaped brackets 11 and two threaded rods 12 with two handles 13 which clamp the device 10 to the fence F by being threaded through the brackets 11 and engaging the fence F. The rods 12 also engage and support two lower hinge pieces 14 (FIG. 2) which are connected to two L-shaped upper hinge pieces 15 by means of two hinges 16. The upper hinge pieces 15 are affixed to and support elongate C-shaped metal brackets 17 that have an upper tang 18 and a lower tang 9. Two vertically disposed, threaded adjustment rods 19 with large adjustment handles 20 affixed to the upper extremity of the adjustment rods 19 are supported by the upper tangs 18 and held in place by two stop washers 21. The adjustment rods 19 pass through two nuts 22 which are affixed to two horizontally disposed support bars 23 so that turning the handles 20 causes the support bars 23 to raise or lower upon the adjustment rod 19. 
     The support bars 23 each have two apertures 24 which are used to mount the wooden overhead fence guide 25. The overhead fence guide 25 has a leading edge 26 which actually engages the work product or the template affixed to the top of the work product. 
     In use and operation, the overhead fence guide 25 can be vertically adjusted in relationship to the table T by rotating the adjustment knobs 20. Thus, the leading edge 26 of the overhead fence guide 25 can be adjusted to engage the work product of FIG. 2 directly or a template TP FIG. 2 affixed to the top of the work product WP. This ensures a more straight cut because the straight leading edge 26 of the overhead fence guide 25 engages the straight edge of the template TP thereby directing the saw blade B in a straight linear path. The conventional fence F can also be used directly by rotating the entire device 10 about the hinges 16 so that it flips out of the way allowing the fence F to be used directly. Furthermore, the device 10 can be reversed on the fence F thereby adjusting to guide the work product from either the left or righthand side. 
     Having thus described the preferred embodiment of the invention, it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the spirit of the invention.