Pry bar
11692364 · 2023-07-04
Assignee
Inventors
Cpc classification
B25C11/00
PERFORMING OPERATIONS; TRANSPORTING
E04G2023/085
FIXED CONSTRUCTIONS
International classification
Abstract
A shaft, a wedge and a fulcrum plate connecting the shaft and wedge and having a transverse cross-section in one plane narrower than the shaft and a cross-section in an orthogonal plane wider than the transverse cross-section.
Claims
1. A pry bar comprising: an elongated shaft at least 12 inches long to be positioned upright and rotated in a selected plane, having a predetermined lateral width and including first and second extremities; the first extremity being in the form of a handle; a tool formed with a wedge; and a laterally elongated fulcrum plate interposed between the second extremity and the tool having a lateral width of less than ⅜ of an inch and first and second opposite upper and lower edges, the first and second opposite upper and lower edges expanding laterally and distally beyond the predetermined cross-section of the shaft and formed on the first upper edge to curve longitudinally and laterally inwardly and form a rounded edge surface so that, when the elongated oval fulcrum plate is disposed in the selected plane, a workman may grasp the shaft and thrust the shaft and the tool forwardly to engage the wedge with a workpiece to cause the wedge to penetrate the workpiece so that as the shaft is rotated in the selected plane, the rounded edge surface will act as a fulcrum about which the bar may be pried.
2. The pry bar of claim 1 wherein: the elongated fulcrum plate incorporates a longitudinal major axis and where the elongated fulcrum plate is at least 4 inches long along the longitudinal axis.
3. The pry bar of claim 1 wherein: the elongated fulcrum plate is 2¾ inches wide and 5½ inches long.
4. The pry bar of claim 1 wherein: the elongated fulcrum plate is at least 6 inches long.
5. The pry bar of claim 1 wherein: the elongated fulcrum plate is 2½ inches wide.
6. The pry bar of claim 1 wherein: the elongated fulcrum plate is at least 4 inches long.
7. The pry bar of claim 1 wherein: the elongated fulcrum plate is ¼ to ⅜ inches in the lateral width.
8. The pry bar in claim 1, wherein: the wedge is formed with a claw.
9. The pry bar in claim 1, wherein: the shaft is 52 inches long.
10. The pry bar in claim 1, wherein: the shaft is between 12 and 52 inches long.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(12) The pry bar of the present invention includes, generally, a shaft 21 (
(13) Pry bars are well known in the construction and demolition industry for prying boards loose and removing fasteners. While numerous different constructions and styles of pry bars have been proposed for various applications, one application that has been severely neglected is deck boards which may have been fastened by fasteners to underlying support beams and have been in place for many years or decades resulting in corrosion of the fasteners to present great resistance to separation of the deck boards from the support beams. Thus, a need exists for a sturdy pry bar which both access the near side of deck boards to pry about a fulcrum to lift the deck boards and which is efficiently constructed to carry high bending movements in the area of the tool for the accessing under the deck board. It is this need to which a present invention is directed.
(14) For the purpose of this description, I refer to the orientation of my pry bar as shown in
(15) The pry bar of the present invention may be constructed of forged steel or other material having construction for resisting bending and the like upon applications of high bending forces.
(16) The elongated shaft 21 is typically formed with a symmetrical transverse cross section such as round, hexagonal or the like. In practice, the shaft and overall length of the device may vary and so may come in different lengths so that access can be had to the workpiece without excessive stooping by the workman. The overall lengths which I have found desirable include but are not limited to 12, 24, 30, 42, 48 and 52 inches, though others will work.
(17) In one preferred embodiment, the handle 23 is curved gently downwardly to form a curved gripping section 31 (
(18) The shaft 21 typically works though a working plane and tapers distally inwardly from the opposite sides at the distal end to form oppositely facing slanting facets 41 (
(19) In practice, I have constructed the shaft 21 with a diameter of about ⅝ of an inch but, for different applications, ⅜ of an inch to ¾ of an inch works well.
(20) The opposite edges of the shaft are then tapered along the facets 41 (
(21) In operation, the pry bar of the present invention may conveniently be utilized to pry deck board 71 away from underlying support beam 73 (
(22) It will be realized by those skilled in the art that from time to time when fasteners 77 are corroded in place, such fasteners will fail to be drawn free with the freeing of the deck board 71, thus leaving them embedded in the support beam. The claw 27 incorporated in the wedge 47 may thus be re-engaged under the head of the fastener 77 to receive the shaft of such fastener within the notch 69 and the handle 31 again lowered to rotate the fulcrum plate 45 about such rolling fulcrum surface 51 as shown in
(23) As will be appreciated by those skilled in the art, the long lever arm provided by the shaft 21 will be effective to, when the handle 31 is pressed downwardly, apply substantial leverage about the rolling fulcrum surface 51 to apply a high magnitude lifting force under the board 71 or under the head of the fastener 77. These forces are then resisted by the vertical cross section of the fulcrum plate to prevent undue bending or failure of such plate.
(24) As will be appreciated by those skilled in the art, the resistance to bending in a beam is proportional to the lateral distance from the neutral axis in the plane in which the torque is applied. Thus, the vertical width of the fulcrum plate is important to the capability of the plate to resist bending as torque is applied due to prying of the shaft as the workman presses down on the handle to rotate about the rolling fulcrum point.
(25) In this regard, it would be appreciated that, when the bar is in the working plane, the height of the plate 45 provides for a substantial body above and below the major axis at 60 so that there is substantial cooperation by the upper and lower halves of such plate as tension and compression forces respectively, are applied thereto during the leveraging work. As will be appreciated, the height of the plate disposes the working part of the beam spaced from the neutral axis to thereby provide substantial resistance to bending to provide a high moment of resistance. Further, by the fulcrum plate having a horizontal cross section narrower than the cross section of the shaft, the workman's view while manipulating the tool from the handle 31 is maximized, thereby providing a clear line of sight to the blade and fork.
(26) Further, by the plate being elongated and formed with the rolling fulcrum curved surface 51 being spaced rearwardly from the blade/fork, the working end of the tool has a substantial reach such that it can be readily utilized for lifting a board 71 while pried over the edge of a plank 81 (
(27) Referring to
(28) In the preferred embodiment, the wedge 89 is formed with an outside transverse dimension of about 5¾ inches but 4½ to 6 inches is acceptable. In this embodiment, I sometimes taper the opposite lateral ends of such blade distally and inwardly at a slight angle of about 5 degrees to the longitudinal axis. In the preferred embodiment, I formed the back edge of such wedge with a thickness of about ½ to ¾ inch and taper the upper and lower surfaces of the blade forwardly to a height of about 1/16 inch over a longitudinal length of about 2½ inches. This presents a wide support surface to be disposed under a deck board to raise such deck board off the support beam over an extended lateral support surface to thus minimize the tendency to break through the body of the deck board and destroy the body of such board, which may well have deteriorated over its life. I formed the forward edge of the wedge centrally with a V shaped notch 99 about 1½ inches deep and of having an open end of about 5/16 to ⅜ inch wide.
(29) Operation of the embodiment shown in
(30) While the fulcrum plate my take many different forms and dimensions, in addition to the above, as one of my preferred embodiments, a fulcrum plate double the size of that shown in
(31) From the foregoing, it will be apparent that the pry bar of the present invention derives a convenient means for removing deck boards and fasteners and the like with a robust connection between the shaft and blade for carrying high torque loads and affording convenient access to the deck boards and viewing of the operation of the working end of the pry tool.
(32) As will be appreciated by those skilled in the art, in practice the pry bar will take many different shapes and configurations depending on the application including different lengths, widths of the puller blade, configuration and thicknesses and widths.
(33) The invention may be embodied in other forms without departure from the spirit and essential characteristics thereof. The embodiments described therefore are to be considered in all respects as illustrative and not restrictive. Although the present invention has been described in terms of certain preferred embodiments, other embodiments that are apparent to those of ordinary skill in the art are also within the scope of the invention. Accordingly, the scope of the invention is intended to be defined only by reference to the appended claims.