Patent Application
20160129580
Not applicable.
The subject matter of the present application is in the field of wrench extensions, i.e. devices added to the handle of a one-piece wrench.
Extenders for increasing the leverage of one-piece, relatively straight-handled wrenches are known, the most common probably being the ubiquitous length of pipe temporarily slid over the wrench handle.
More sophisticated examples include U.S. Pat. No. 5,570,617 to Love and U.S. Pat. No. 6,626,069 to Cooper.
The Love patent discloses an extendible extension handle for wrenches, ratchets, and tire irons to increase leverage, and uses a tubular inner handle and a telescoping outer handle assembly.
The Cooper patent discloses an angled adapter bar with a U-bolt for receiving the handle of a wrench, and a leverage bar for engaging the other end of the adapter bar, so that when all three are connected they multiply the force applied by the user to the wrench.
The foregoing prior art and other prior wrench extensions seem to focus on increasing leverage more than they address the problem of extending reach. In the case of nuts or bolts deeply recessed in tight places, reach is often the more important factor.
I have invented a wrench extender that increases both leverage and reach, and that works with most types of common one-piece wrenches, including open-end wrenches, combination wrenches, and box-end wrenches (hereafter collectively “wrenches”). My wrench extender can be used with both single- and double-ended wrenches, but is especially advantageous in combination with double-ended wrenches. My wrench extender also accommodates the offset angle of one or both ends of a double-ended wrench.
My wrench extender includes a handle-supporting base having two spaced vertically-opening clamping receptacles on an upper surface of the base for securely holding a wrench handle. The inner end of the base terminates at a downwardly-angled neck defining a combined recess and stop for one end of a double-ended wrench. The inner end of the angled neck is connected to a grip portion that is aligned with the handle-supporting base. If the extender is combined with a double-ended wrench, the outer end of the wrench extends beyond the outer end of the base to engage a nut or bolt, while the inner end of the wrench extends beyond the inner end of the base and is located in the angled neck between the base and the grip.
In a further form, the angled neck includes a ramp portion adjacent the handle-supporting base, the ramp angled downwardly relative to the base corresponding to the angle of an angled end of a double-ended wrench.
In a further form, the angled neck includes a stop in the form of a stud projecting vertically up from the neck to a height at or above the height of the upper surface of the handle-supporting base. In an alternate form, the stop is formed by an inner vertical wall or shoulder formed by the junction of the inner end of the angled neck and the grip.
These and other features and advantages of the invention will become apparent from the detailed description below, in light of the accompanying drawings.
Referring first to
Extender 10 includes a handle-supporting base 12 with an upper surface 14, an outer end 16, and an inner end 18. In the illustrated example, extender 10 is made from a single piece of durable metal, for example drop-forged steel, although other materials and/or methods of forming are possible: e.g., other metals or plastics formed by machining or molding or casting, and multi-piece constructions.
Extender 10 further includes an elongated clamping receptacle means 20 defining two or more longitudinally-spaced clamping points for a wrench handle. In the illustrated example, receptacle means 20 is formed by two spaced clamping receptacles 20 on the upper surface 14 of base 12. It will be understood that a single elongated receptacle, for example extending over a majority of the length of handle-supporting base 12, could be used in place of the two spaced receptacles 20, and longitudinally spaced regions or ends of the receptacle would define the clamping points where provided with handle-clamping or securing means. However, the spaced receptacles 20 are preferred, with advantages including reduced weight and cost.
Clamping receptacles 20 secure the wrench to the upper surface 14, and transfer leverage force to the sides of the wrench handle 42 when the extender is turned. Clamping receptacles 20 each include a pair of spaced rigid ears or sidewalls 20a extending upwardly past surface 14 from the sides of base 12 a height equal to or greater than the top-to-bottom thickness of a corresponding wrench handle, forming a generally U-shaped receptacle for the wrench handle. Each receptacle is provided with an associated securing member 20b such as a clasp (illustrated) or strap or equivalent structure for locking the wrench handle to the upper surface 14 of base 12 by closing off the open upper end of the associated receptacle 20. In the illustrated example, securing member 20b is a spring clip pivotally secured to one of the sidewalls 20a on a first side of base 12, moveable between open and closed positions, and frictionally engaged with the sidewall 20a on the other side of base 12 when closed. In the case of a single elongated receptacle, it would be possible to use two or more spaced closure devices such as clips 20b, or a single elongated closure device such as an elongated clip 20b.
Further in the illustrated example, inner surfaces 20c of the spring clips are provided with resilient and/or frictional pads 21 to engage the wrench handle in compression and/or friction when the clips are closed, in order to prevent the wrench handle from moving longitudinally on upper surface 14 of base 12. Alternately, or additionally, pads 21 could be placed on upper surface 14 within receptacles 20. The upper surface 14 of base 12 could also be provided with similar compressible and/or frictional material, such as rubber or high-density foam, or it could be provided with non-slip texturing. Alternately, spring clips 20b or other securing means could be contoured or located to directly engage the wrench handle with sufficient compressive force to hold the handle in place without the need for pads or texturing.
Wrench extender 10 has a downwardly-offset neck 22 at the inner end 18 of base 12. Neck 22 includes a downwardly-angled ramp portion 24 approximating or matching the angle of wrench box-end 46 relative to the axis of the wrench handle. Stop 26 in the example of
To further prevent wrench 40 from shifting longitudinally in the receptacles 20, neck 22 is configured to provide a vertical stop at the inner end of the wrench. In a first form shown in
In the illustrated example of
Neck 22 is offset or angled downwardly relative to handle-supporting base 12 to receive any angled portion of the inner secured end of the wrench 40, such as the angled box-end 46 shown in the example. Since sets of wrenches with angled ends usually come with standard angles, a predetermined neck angle is usually sufficient to accommodate multiple wrenches.
Referring next to
In the examples of extender 10 above, grip 28 is substantially aligned with handle-supporting base 12. This alignment keeps the height of the extender above the wrench to a minimum, and also allows more effective use of a wrench secured to the extender. By substantially aligned is meant both true alignment of the base 12 and grip 28 along the same axis, as well as variations in the height of grip 28 above base 12 less than the height of clamping receptacles 20.
Handle-supporting base 12 on extender 10 has a maximum side-to-side width equal to or less than the width of a wrench handle, and the bottom surface 13 (like upper surface 14) is preferably flat. These features maximize clearance and provide a stable base for the body of the wrench.
In operation, the extender 10 is used by placing a wrench handle 42 in receptacles 20 with an outer end of the wrench (e.g., 44) extending beyond the outer end 16 of the extender, and the inner end of the wrench (e.g., box end 46) extending into neck 22 into engagement with stop 26 (or 126). Receptacle closures 20b are closed over the wrench handle 42 to lock the wrench 40 to base 12. A user can then operate the wrench 40 using extender 10 through grip 28, at any angle and in any wrench-turning direction.
It will finally be understood that the disclosed embodiments represent presently preferred examples of how to make and use the invention, but are intended to enable rather than limit the invention. Variations and modifications of the illustrated examples in the foregoing written specification and drawings may be possible without departing from the scope of the invention. It should further be understood that to the extent the term “invention” is used in the written specification, it is not to be construed as a limiting term as to number of claimed or disclosed inventions or discoveries or the scope of any such invention or discovery, but as a term which has long been conveniently and widely used to describe new and useful improvements in science and the useful arts. The scope of the invention should accordingly be construed by what the above disclosure teaches and suggests to those skilled in the art, and by any claims that the above disclosure supports in this application or in any other application claiming priority to this application.
