Patent Application
20060213014
This invention pertains to tool, in particular, a linear striking device or hammer that can be converted to a screwdriver.
Hammers and other devices for driving nails into a work surface are well known in the art. Most of these devices are of the claw hammer variety, or some variation thereof, which uses a hammer head attached to a handle. These types of hammers may include another functional implement, such as a claw for removing nails, at the opposite end of the striking surface.
The most commonly used hammers are attached to a handle that extends approximately 90° from the head of the hammer. This arrangement allows the user to generate a striking force by swinging the hammer up and down or back and forth in relation to the work surface that is being struck. The need to swing the conventional hammer back and forth can, however, become problematic if the work surface presents little or no room in which to move the hammer, thereby preventing the user from generating a striking force.
In order to overcome this problem, linear hammers have been developed in which a rod is moved within a guide tube so as to generate a linear striking force against a nail. An implement of this type is disclosed, for example, in U.S. Pat. No. 2,587,944 (Williams) and U.S. Pat. No. 3,979,040 (Denin). A shortcoming of these types of nail drivers, however, is that the striking rod may be pulled out of the guide tube during use in an attempt to generate more force. Furthermore, the user may be required to repeatedly retract and advance the rod in order to drive the nail the required depth into the work surface. This repetitive action can cause fatigue and quite possibly injury to the user. Additionally, these types of nail drivers require the use of two hands, one to position and steady the guide tube and one to operate the striking rod. This can at times be cumbersome and awkward depending on the size of the area in which one is working.
U.S. Pat. No. 5,875,950 (Nuss et al.) discloses an attempt to overcome the problem of having the striking rod separate from the guide tube. This is done by utilizing a weight in the handle in which the guide tube is seated. This, of course, results in a heavy hammer that results in greater fatigue to the user.
It is for these reasons that a linear hammer that could allow one to single-handedly drive nails into a work surface would be an important improvement in the art. Furthermore, a device that could be converted to a screwdriver and still allow for the application of a force to set a screw into a work surface prior to initiating a screwing force would also be an important improvement in the art.
The invention is directed to a tool comprised of a handle which defines a passageway therethrough, a guide tube that extends through the channel, a rod positioned in the guide tube, a spring surrounding the guide tube within the channel, a depth adjuster attached to a first end of the rod and secured to the handle, and a bushing encircling the guide tube adjacent an end of the handle distal from the depth adjuster.
a is a sectional view of the tool shown in
As shown in
In an embodiment, the handle 12 has a threaded first end 30 and the depth adjuster 22 is screwed to the first end 30 of the handle 12. This allows for a more accurate adjustment of the rod 18 in order to predetermine the depth at which a nail 32 will be driven into a work surface 34. The depth adjuster 22 may also include indicia 36, as shown in
The protective tip 38 may be made of any suitable material including rubber. In an embodiment, the handle 12 may have a tapered second end.
The assembly of the tool 10 will now be described. The following example further illustrates the invention but, of course, should not be construed as in any way limiting its scope. It is important to note that the sizes and measurements cited in this example are exemplary only and are not limiting in any way on the spirit and scope of the invention.
Any suitable material including, but not limited to, steel may be used to manufacture the tool 10. In one embodiment, the handle 12 may be made of steel and be approximately 8½″ long and 1 and 3/16″ in diameter. The second end 28 of the handle 12 has an opening center drilled ½″ diameter by 7½″ deep, with the first ½″ of the opening threaded. The first end 30 of the handle 12 is turned down to a ¾″ outside diameter by 1½″ deep and has sixteen threads per inch. A 3/16″ opening 44 is center drilled in the first end 30. This opening 44 continues into the ½″ diameter opening 46 inside the handle 12, thereby defining the channel 14 that extends through the handle 12. In a particular version of the embodiment, the handle 12 may be covered by a protective grip 48, as shown in
The depth adjuster 22 may be made of steel two inches long by 1 3/16 inch in diameter. A first end 50 of the depth adjuster 22 has an opening 52 center drilled at two diameters. The opening 52 is first center drilled ¾″ diameter by 1⅝″ deep and is threaded the full depth with sixteen threads per inch. The opening 52 is then center drilled at the bottom of the first center drill at 3/16″ diameter by ¼″ deep. The rod 18, which may be of 3/16″ diameter solid steel, has one end hardened and a second end pressed into the 3/16″ diameter opening of the depth adjuster 22. In addition to being hardened, the one end of the rod 18 may be textured so as to prevent the nail from moving toward the guide tube. The depth adjuster's internal ¾″ threads are then screwed onto the ¾″ external threads of the handle 12. Indicia marks 36 may be included on the depth adjuster 22 and the handle 12. These marks 36 may be two small round indentations of contrasting color, one on the handle 12 and one on the depth adjuster 22, as shown in
In another embodiment, as shown in
The guide tube 16 may be made of stainless steel and may be 11″ long by 5/16″ outside diameter and 3/16″ inside diameter. One end 58 of the guide tube 16 is inserted into the second end 28 of the handle 12 where it encircles the rod 18 and is encircled by at least one spring 20. The spring 20, which may be a 7½″ long compression spring, for example, slides over the guide tube 16 up against a spring retainer 60. The guide tube 16 is held in place by a bushing 26 attached to the second end 28 of the handle 12. This bushing 26, which holds the tool 10 together as one piece, may be a standard 5/16″ brake line fitting with ½″ external threads on one end and 1/2″ hex nut on the other. When positioned over the guide tube 16, the hex nut is adjacent the second end 28 of the handle 12. In an embodiment, the bushing 26 may be used to secure the guide tube 16 in a retracted position.
In one embodiment, a bell shaped finger grip 62 may extend form the end 40 of the guide tube 16 distal to the handle 12. This finger grip 62 may be made of aluminum and include a 5/16″ opening 64 in the one end 66 in which the guide tube 16 is pressed and two 3/16″ openings 70, 72 in the opposite end 68. As shown in
When in operation, the user first determines the depth at which he desires to drive the nail 32 into the work surface 34. This is done by adjusting the distance of the depth adjuster 22 from the first end 30 of the handle 12. For example, if one desires the nail 32 to be flush with the work surface 34, the depth adjuster 22 is positioned so as to contact the first end 30 of the handle 12. In order to adjust the rod 18 so that a portion of the nail 32 extends from the work surface 34, the depth adjuster 22 is positioned a respective distance from the first end 30 of the handle 12. This means that if one desires the head of the nail 32 to extend a ¼″ from the work surface 34 to allow for the hanging of, for example, a picture or a string of lights, the depth adjuster 22 would be positioned ¼″ from the first end 30 of the handle 12.
One way of obtaining a precise measurement is to incorporate a threaded micro adjuster that allows infinite depth settings from flush with the work surface 34 to approximately 1¼″. This is done, in one embodiment, by providing the adjuster with sixteen threads per inch thus resulting in a 1/16″ depth change for every 360° of revolution of the adjuster.
In such an embodiment, one 360° revolution of the depth adjuster 22 results in the head of a nail 32 being driven into a work surface 34 extending 1/16″ above the surface 34. Two 360° revolutions results in a ⅛″ protrusion, four revolution a ¼″ protrusion and eight revolutions a ½″ protrusion. The gap between the handle 12 and the depth adjuster 22 indicates the amount of nail 32 that remains protruding from the work surface 34. This gap can be observed visually, by touch, or by counting the number of 360° revolutions the depth adjuster 22 is turned.
After the operator sets the depth adjuster 22 to the desired setting, a nail 32 is inserted head first into the open end 40 of the guide tube 16 distal to the depth adjuster 22. In one embodiment, the open end 40 of the guide tube 16 is covered with a protective tip that may include a magnet 42, as is shown in
After positioning the end of the guide tube 16 against the work surface 34, the operator can then, with one hand, loosely grip the handle 12 and by using short, in-and-out strokes, drive the nail 32 into the work surface 34, as shown in
When utilizing the tool 10 as a screwdriver, the operator positions the screw in the open end 40 of the guide tube 16 where it is held in place by a magnet 42. The guide tube 16 is positioned against the work surface 34 and the handle 12 is rotated with respect to the guide tube 16, as shown in
In an embodiment, the tool 10 has an extension rod 80 for remote use of the tool 10. In an embodiment, as shown in
In an embodiment, the finger grip 62 is capable of receiving at least one detachable tool accessory. Examples of such tool accessories will now be further described.
In an embodiment, an angle guide 94 is detachably coupled to an end 40 of the guide tube 16 distal from the depth adjuster 22. In an embodiment, the angle guide 94 snaps onto the tool 10 over the finger grip 62, as shown in
In an embodiment, the tool 10 has a spacer 100 detachably coupled to the end 40 of the guide tube 60 distal from the depth adjuster 22. In an embodiment, the spacer 100 snaps onto the tool 10 over the finger grip 62. In an embodiment, the spacer 100 defines a passage 102 through which the rod 18 of the tool 10 passes. In an embodiment, the spacer 100 maintains a substantially uniform distance between the work surface 34 and raised objects, e.g., nails 32, which are substantially perpendicular to the work surface 34. In another embodiment, the spacer 100 maintains a substantially uniform distance between an edge of a work surface 34 and an object, e.g., a nail 32, being inserted into the work surface. In an embodiment, as shown in
In an embodiment, the tool 10 has a light source attachment 106 for illuminating the end of the tool 10 and the work surface 34. In an embodiment, the light source 106 is coupled to the end 40 of the guide tube 60 distal from the depth adjuster 22. In an embodiment, the finger grip 62 may be clear plastic and backlit, thereby also serving as the light source 106, as shown in
In an embodiment, the tool 10 has a centralized center of gravity, thereby resulting in a tool 10 that is balanced and easier to manipulate than other linear hammers.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. It should be understood that the illustrated embodiments are exemplary only, and should not be taken as limiting the scope of the invention.
