1. Technical Field
The invention relates generally to hand tools and more particularly to hand tools adapted for use with threaded rods.
2. Description of Prior Art
A threaded rod is a metal rod having a continuous thread about its exterior. The thread may be “right handed” or “left handed”, describing how the thread winds about the rod. Most threaded rods have right hand threads. Unlike a bolt, a threaded rod does not have an end protuberance for gripping. A threaded rod is typically used by inserting one or both ends into threaded holes, though nuts may also be placed thereon.
The convention for describing a threaded rod is to provide the diameter of the threaded rod in fractions of an inch and to provide the number of threads per inch. For example, one might ask for a “½-13 threaded rod,” which would describe a threaded rod having a nominal diameter of one half of an inch, and having thirteen threads to the inch as measured along a line parallel to the longitudinal axis of the threaded rod. Metric measurements of threaded rods are also common. In addition to the diameter of the threaded rod and the thread count, the thread of a threaded rod may also be characterized by its pitch and thread profile. Often these are standardized for ease of use, but they may also vary.
Threaded rods are commonly used in many mechanical applications. They are particularly found in small engines. Threaded rods may need to be adjusted or removed from their threaded holes, or reinserted therein. Over time, the threaded rod may become tightly bound to the threaded hole, making removal or adjustment of the threaded rod difficult, or the threaded hole may become dirty or damaged, making insertion of a threaded rod therein difficult.
Previously, persons needing to remove, adjust, or insert a tightly bound threaded rod from a threaded hole have had several less than optimal options. One method commonly used is the two-nut method. The user places two nuts onto the threaded rod, one on top of the other, thereby “locking” them against each other. After locking the nuts against each other, one of the nuts is gripped with a gripping device and then rotated, thereby rotating the threaded rod along with it (on a threaded rod having a right hand thread, to loosen the rod the lower nut is gripped and rotated, while to tighten the rod the upper nut is gripped and rotated; if the thread is left handed, the process is reversed). This method is time consuming and risks locking the nuts onto the threaded rod. It also cannot work where both ends of the threaded rod are inserted into threaded holes or are otherwise inaccessible.
A second method commonly used is to wrap a rag around the threaded rod and place a clamping device onto the rag, such as a vice grip or locking pliers. The rag is gripped with enough force to allow for rotation of the threaded rod. However, in applying sufficient force there is a risk that the threads of the rod will be damaged. The rag itself offers little protection. Gauging the exact amount of force necessary to move the rod but not to damage its thread is extremely difficult, and made even more so by the varying thicknesses of rags. The most common damage to a thread that occurs when using this method is to break or bend the crest of the thread, such that the distanced between the crests and/or flanks of the thread are no longer uniform. This prevents the thread from mating with another thread, either found in a nut or in a threaded hole.
A third method used is to grip the threaded rod directly with a clamping device. This frequently results in the destruction of a portion of the threads, through bending or breaking, and renders the threaded rod useless.
None of the foregoing methods adequately addresses the problem of removing, adjusting, or inserting a threaded rod easily and without damage to its threads. There is thus a need to overcome the deficiencies of the known art and to provide a device to easily and safely remove, adjust, or insert threaded rods.
It is therefore an objective of this invention to provide an improved hand tool for use with threaded rods which can be used to rotate a threaded rod with out damaging its thread.
It is a further objective of this invention to provide an improved hand tool for use with threaded rods which can be used to easily rotate a threaded rod.
It is yet a further objective of this invention to provide an improved hand tool for use with threaded rods which is easy and cost efficient to manufacture.
It is yet a further objective of this invention to provide a set of improved hand tools for use with many different sizes of threaded rods.
Other objectives of this invention will be evident from the following disclosure.
The present invention is directed to an improved hand tool for use with threaded rods. The present invention comprises a pair of partially threaded jaws that are used to grip threaded rods in conjunction with a gripping tool, such as a “Vice-Grip”™ locking pliers or a channel lock pliers. The present invention allows the user to easily and quickly clamp onto any size threaded rod without damaging its threads, thereby allowing the user to rotate the threaded rod for insertion, adjustment, or extraction purposes.
Because threaded rods come in many different diameters, thread counts, pitch, and thread profiles, the present invention also contemplates a set of multiple pairs of jaws with varying characteristics as needed to mate with a wide range of threaded rods.
The present invention overcomes the deficiencies of the known art by providing a pair of partially threaded jaws that together may be placed around a threaded rod over its threads. The threads of the jaws mate with the threads of the threaded rod. The two jaws are placed on opposite sides of the threaded rod from each other, thereby substantially surrounding the threaded rod. A force applied to the jaws from opposite directions moves the jaws toward each other and against the threaded rod. The threads of the jaws are slightly deeper than the threads of the threaded rod, thereby allowing the jaws to grip the threaded rod at the root of its threads so as to avoid damaging the threads of the threaded rod.
In the preferred embodiment the pair of jaws is joined by a hinge. The hinge keeps the jaws together and allows them to be easily and properly aligned on the threaded rod when in use. Other embodiments are also contemplated, such as keeping the pair of jaws together by the use of magnets, or aligning the jaws with matched engagement pins and engagement holes.
In yet another embodiment, pivotally cooperating handles are attached to the jaws, so that a separate clamping device is not needed to apply a force to the jaws to grip the threaded rod. The handled configuration may be oriented whereby the handles are aligned substantially perpendicular to the threaded rod when the hand tool is in use, or oriented whereby the handles are aligned substantially parallel with the threaded rod, whichever better serves the purpose.
Other features and advantages of the invention are described below.
The hand tool 1 of the present invention is intended to be used with a threaded rod 10. The threaded rod 10 is characterized as having a core 14 and an external thread 12 formed on the core 14. The external thread 12 of the threaded rod 10 has a given nominal diameter, pitch, thread profile, thread count, and depth. The external thread 12 further has a pair of flanks 16 extending outward from the core 14 and meeting at a crest 18.
The hand tool 1 of the present invention is comprised of a first jaw 100 and a second jaw 200. See
The inner surface 110 of the first jaw 100 has a series of internal screw threads 112 formed thereon. Each internal screw thread 112 has the same pitch (i.e., deviation from the normal), thread profile (i.e., shape of the thread), and thread count as the external thread 12 on the threaded rod 10. Each of the internal screw threads 112 of the first jaw 100 also comprises a pair of flanks 116 extending from the inner surface 110 of the first jaw 100 and meeting at a crest 118. Configured as such, the internal screw threads 112 are suitably adapted for mating engagement with the external thread 12 of the threaded rod 10.
The second jaw 200 likewise has an inner surface 210 and an outer surface 220. The inner surface 210 of the second jaw 200 is concave and has a shape substantially corresponding to an arc of the same circle defining the arc of the inner surface 110 of the first jaw 100. The arc of the inner surface 210 of the second jaw 200 has a length L′, where L′ is less than or equal to the circumference of the circle less length L. In the preferred embodiment the length L′ is just slightly less than one half the circumference of the circle. Thus, in the preferred embodiment lengths L and L′ together are just slightly less than the circumference of the circle. In the most preferred embodiment the first jaw 100 and the second jaw 200 have substantially the same shape. However, in other embodiments the lengths L and L′ may be of unequal length.
The inner surface 210 of the second jaw 200 has a series of internal screw threads 212 formed thereon. Each internal screw thread 212 has the same pitch, thread profile, and thread count as the external thread 12 on the threaded rod 10. Each of the internal screw threads 212 of the second jaw 200 also comprises a pair of flanks extending from the inner surface 210 of the second jaw 200 and meeting at a crest. Configured as such, the internal screw threads 212 are suitably adapted for mating engagement with the external thread 12 of the threaded rod 10.
So configured, the first and second jaws 100,200 of the hand tool 1 may be simultaneously engaged upon opposite sides of the threaded rod 10, with the first and second jaws 100,200 lying in substantially the same plane with the threaded rod 10 positioned between them. See
To accommodate the use of a clamping device, the outer surface 112 of the first jaw 100 may be substantially convex with at least one gripping side 122. See
Various configurations of the outer surfaces 120,220 of the first and second jaws 100,200 which can accommodate a clamping device are contemplated by the present invention. One such configuration is for the hand tool 1 to have a substantially hexagonal profile. See
To be usable as described, the jaws 100,200 of the hand tool 1 should be made of a very hard, durable material. Preferably, the first and second jaws 100,200 are made of a metal, such as steel, stainless steel, a metal alloy, and the like. Other materials exhibiting similar hardness and durability may also be used.
The hand tool 1 may be configured to further reduce the risk of damage to the external thread 12 of the threaded rod 10 during engagement. In this embodiment, for each internal screw thread 112 of the inner surface 110 of the first jaw 100, each internal screw thread 112 has a depth greater than the depth of the external thread 12 of the threaded rod 10. See
The two jaws 100,200 of the hand tool 1 may be connected to each other by use of a hinge 300. See
In one embodiment of the hinge 300, the hinge further comprises a substantially rigid first portion 320, a substantially rigid second portion 322, and a pivot mechanism 330. The pivot mechanism 330 is interposed between and integrated with the first and second portions 320,322 of the hinge 300. See
In yet another embodiment of the hinge 300, the hinge is substantially monolithic and flexible. This is shown in
In another embodiment, means other than a hinge 300 are used to keep the two jaws 100,200 together when not in use and to keep the two jaws 100,200 properly aligned when the hand tool 1 is in use on a threaded rod 10. In one such embodiment, the outer surface 120 of the first jaw 100 further comprises a first end and a second end located opposite the first end. On the outer surface 120 of the first jaw 100 at the first end is a first face 130. On the outer surface 120 of the first jaw 100 at the second end is a second face 140. Similarly, the outer surface 220 of the second jaw 200 has a first face 230 and a second face 240. The first face 130 of the first jaw 100 is substantially planar, as are the second face 140 of the first jaw 100 and the first and second faces 230,240 of the second jaw 200. The first face 130 of the first jaw 100 is oriented towards and is substantially aligned with the first face 230 of the second jaw 200, and the second face 140 of the first jaw 100 is oriented towards and is substantially aligned with the second face 240 of the second jaw 200, when the first and second jaws 100,200 of the hand tool 1 are simultaneously engaged upon opposite sides of the threaded rod 10. See
In this embodiment, the first face 130 of the first jaw 100 has one or more engagement pins 132 depending from the first face 130 of the first jaw 100 and oriented substantially perpendicular to the first face 130 of the first jaw 100. The first face 230 of the second jaw 200 has a like number of engagement holes 234 formed into the first face 230 of the second jaw 200, each such engagement hole 234 suitably adapted to receive a corresponding engagement pin 132 from the first jaw 100 when the first and second jaws 100,200 of the hand tool 1 are simultaneously engaged upon opposite sides of the threaded rod 10. See
In another embodiment, the first face 130 of the first jaw 100 is magnetically attracted to the first face 230 of the second jaw 200, and the second face 140 of the first jaw 100 is magnetically attracted to the second face 240 of the second jaw 200. This accomplishes the purpose of holding the two jaws 100,200 together without use of a hinge.
In an alternative embodiment of the hand tool 1, the hand tool 1 further comprises a first handle 410 and a second handle 412. The first handle 410 is substantially elongate and rigid, and is fixedly attached to the first jaw 100. The second handle 412 is substantially elongate and rigid, and is fixedly attached to the second jaw 200. The first and second handles 410,412 are in connection with each other by a pivot 420. The pivot 420 is suitably adapted to pivotally connect the first handle 410 with the second handle 412. See
The present invention also contemplates a set of hand tools 1 suitable for use with a plurality of threaded rods 10. Each set may be configured to work with a corresponding set of threaded rods 10, for example threaded rods 10 all having the same combination of pitch, thread profile, and thread count but having different nominal diameters. In such a set, the most common sizes of threaded rods 10 would have corresponding hand tools 1 designed to fit them. This is analogous to socket sets which contain various sockets sized to fit common nut sizes. The hand tools 1 may be configured with Imperial measurements (e.g., based on inches) or metric.
Modifications and variations may be made to the disclosed embodiments of the present invention without departing from the subject or spirit of the present invention as defined in the following claims.