This invention relates to a wrench, more particularly a pipe wrench that is self-adjusting and that is suitable for use in remote applications, such as a keyhole.
Gas utilities perform several operations on underground pipeline systems including the removal and installation of tee caps, insertion of couplings and pipeline surface preparations. When performed through a traditional bell hole, the performance of these operations generally does not represent a significant problem. For example, when removing and installing tee caps, workers are able to easily determine the cap size, type of cap and other physical attributes of the cap and are able to access the cap with cap-specific tools/accessories or with common adjustable tools. However, performance of these operations through a keyhole is substantially more problematic.
“Keyholing” and “potholing” refers to the excavation of a hole to access or repair utilities. Potholing and keyholing are preferred over other techniques such as digging shovels, backhoes, and the like which often result in damage to the utilities and the corresponding demand for expensive repair and reconstruction. In addition to the increased costs associated with damage repair and increased labor costs associated with digging, such damage may present danger to workers or others in the immediate vicinity of the excavation.
Typically, a keyhole is 12-18 inches in diameter and up to about ten feet in depth and visibility down the keyhole is limited, thereby precluding the use of conventional tools to access the utility. It is very difficult to determine the type of cap, fitting, or pipe, its exact size, and whether or not the workers have the proper equipment to perform the necessary work. In addition, the design of tee caps and fittings is not standardized between manufacturers, thereby making it very difficult to determine every variation in design and size and to have a specific tool or accessory for each. Often times the type of fitting or size of pipe is not known until it is unearthed. Thus, to be equipped for every possible design and size would require an excessive amount of tools and accessories on the crew truck. In addition, due to the relatively small amount of space in keyholes in which to work, tool control and maneuverability can be problematic.
Accordingly, it is one object of this invention to provide a wrench that is suitable for use in remote applications.
It is one object of this invention to provide a wrench that addresses some of the problems associated with the use of conventional tools in keyhole applications.
It is one object of this invention to provide a wrench for use in keyhole applications that is readily adaptable to the design and size of any tee cap, pipe, and fitting.
These and other objects of this invention are addressed by a self-adjusting type wrench comprising a rigid adapter body comprising a heel jaw, a hook jaw disposed opposite the heel jaw and pivotably connected with the rigid adapter body such that the hook jaw is pivotable within the plane of the heel jaw, adjustment means for automatically adjusting the distance between the heel jaw and the hook jaw, and a removable elongated drive handle connected with the rigid adapter body such that rotation around a longitudinal axis of the handle results in application of a force on an object disposed between the heel jaw and the hook jaw. In accordance with one embodiment of this invention, at least one of the heel jaw and the hook jaw comprises a plurality of grasping teeth.
These and other objects and features of this invention will be better understood from the following detailed description taken in conjunction with the drawings wherein:
A fully assembled self-adjusting wrench in accordance with one embodiment of this invention is shown in
Referring to
Hook jaw 11 is a substantially planar hook-shaped structure of a given thickness having a grasping end 27 and a pivot end 28. Grasping end 27 comprises hook jaw grasping surface 25 facing grasping section 23 of heel jaw 12. In accordance with one embodiment of this invention, grasping surface 25 forms a plurality of grasping teeth.
The thickness of hook jaw 11, in accordance with one embodiment of this invention as shown in
The self-adjusting feature of the self-adjusting wrench of this invention is provided, in accordance with one embodiment of this invention, by torsion spring 50 shown in
Rigid adapter body 22 forms at least one polygonal bore 15, which is adapted to receive a correspondingly shaped end 17 of the elongated drive handle 40. In accordance with one embodiment of this invention, the at least one polygonal bore is oriented substantially perpendicular to the plane of planar surfaces 30, 31. In accordance with one preferred embodiment of this invention, the at least one polygonal bore has a square shape, thereby rendering it suitable for receiving common square drives and allowing the self-adjusting wrench assembly to be used as an attachment to long handled keyhole tools or even common hand tools that can accept a square drive socket. In accordance with one preferred embodiment of this invention, rigid adapter body 22 forms at least one polygonal bore on opposed sides of the rigid adapter body to which the elongated drive handle 40 may be attached, thereby enabling the wrench to be used in either a tightening or loosening mode. That is, when used in a tightening mode, elongated drive handle 40 is inserted into a bore on one side of rigid adapter body 22 and, when used in a loosening mode, the elongated drive handle is inserted into the bore on the opposite side of the rigid adapter body.
The self-adjusting wrench of this invention can be used in different axes with respect to the axis of the pipeline on which work is being performed. The two most common axes are the vertical axis (substantially perpendicular to the axis of the pipeline) or in the horizontal axis (substantially parallel to the axis of the pipeline). To facilitate use in the vertical axis in accordance with one embodiment of this invention, the self-adjusting wrench comprises a laterally extending retaining element 20 connected with said elongated drive handle 40 proximate rigid adapter body 22 by rotation means for rotating the retaining element around the longitudinal axis of the elongated drive handle. The retaining element, as shown in
While in the foregoing specification this invention has been described in relation to certain preferred embodiments thereof, and many details have been set forth for the purpose of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of this invention.
Number | Date | Country | |
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60675040 | Apr 2005 | US |