Tool for hard to reach fasteners

A hand tool includes a handle and an arm assembly. The handle has a mounting portion. A square peg on the mounting portion is removably secured in a square hole in a base of the arm assembly. The arm assembly includes a pair of parallel arms each have an inner end portion pivotally mounted to the base on a pair of pins which extend parallel to the axis of the peg. A tool is pivotally connected to the outer end portion of each of the parallel arms. The handle is capable of being mounted to the base of the arm assembly in a first position and in a second position rotated 180.degree. from the first position.

FIELD OF INVENTION 
This invention relates generally to hand tools and more particularly to a 
hand tool which is especially adapted for use with fasteners that are in 
hard-to-reach places. 
BACKGROUND OF THE INVENTION 
An ordinary wrench or pliers can be used to remove or apply a fastener if 
the fastener is within easy reach and readily accessible. Often, however, 
the fastener, due to its location, is not readily accessible. What is 
needed is a hand tool which is capable of almost universal use, even when 
the fastener is difficult to reach. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, a hand tool is provided 
comprising an arm assembly having first and second parallel arms pivoted 
at one end to a base and at the other end to a tool. A handle is removably 
secured to the base. 
More specifically, the handle has an end portion provided with a peg on 
which the base of the arm assembly is mounted. The base, arms and tool 
define a parallelogram linkage swingable in a plane which is parallel to 
the handle. 
Preferably, the peg is rectangular so that the handle may be removed from a 
first position, rotated 180.degree. and re-applied to the peg in a second 
position 180.degree. from the first position. 
In the preferred construction about to be described, the handle has a 
mounting portion formed with an L-shaped recess having first and second 
flat surfaces which are perpendicular to one another. The peg, which is 
preferably square, projects outwardly from the first flat surface. The 
base has a mounting portion provided with a square opening in which the 
peg is inserted with a close fit to connect the handle to the base with 
the handle disposed in a first position. The peg is removable from the 
hole to disconnect the handle from the base so that the handle can be 
rotated 180.degree. to a second position and the peg re-inserted in the 
hole. The peg when inserted in the hole prevents rotation of the handle 
relative to the base. The mounting portion of the base has a flat surface 
in flush abutting engagement with the second flat surface of the recess in 
the mounting portion on the handle as a further means of preventing 
rotation of the handle relative to the base. 
One object of this invention is to provide a hand tool having the foregoing 
features and capabilities. 
Another object is to provide a hand tool which is constructed of a 
relatively few simple parts, is rugged and durable in use, and is capable 
of being readily manufactured and assembled. 
These and other objects, features and advantages of the invention will 
become more apparent as the following description proceeds, especially 
when considered with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now more particularly to the drawings, and especially to FIGS. 
1-6, a hand tool 10 is shown having an elongated handle 12, an arm 
assembly 14, and a tool 16 having a claw 17 for gripping a fastener such 
as a nut N. 
The arm assembly 14 comprises a pair of substantially identical, elongated, 
laterally spaced-apart, parallel arms 18 and 20. The outer ends of the 
arms are slotted to receive the shank 21 of the tool. The outer ends of 
the arms are pivoted to the shank 21 by pivot pins 22 and 24. The inner 
ends of the arms are pivoted to a base 26 by pivot pins 28 and 30. Pins 
22, 24, 28 and 30 have parallel pivot axes. 
More specifically, the base 26, which is shown in detail in FIG. 3, has a 
mounting portion 32 which is bifurcated to provide a slot 33 into which 
the inner ends of the arms 18 and 20 extend. The pivot pins 28 and 30 
extend across the slot 33 through aligned holes on opposite sides of the 
slot. The pivot pins 22 and 24 at the outer ends of the arms are spaced 
from one another the same distance as the pivot pins 28 and 30 at the 
inner ends of the arms and are spaced from the respective pivot pins 28 
and 30 the same distances so that the arm assembly 14 consisting of the 
base 26, arms 18 and 20 and the shank 21 of the tool, pivoted together by 
pins 22, 24, 28 and 30, form a parallelogram linkage. 
The mounting portion 32 of the base 26 has an integral extension 34 to 
which the handle 12 is connected. The extension 34 has a flat surface 36 
lying in a plane established by the longitudinal axes of the arms 18 and 
20. The flat surface 36 together with a flat surface 38 of the mounting 
portion meet at right angles to form an L-shaped recess. A square hole 40 
extends through the extension 34 with two opposite parallel sides of the 
hole parallel to the flat surface 38 and the remaining two sides 
perpendicular thereto. The extension 34 has flat parallel side surfaces 39 
and 41. 
The handle 12 has a mounting portion 42 at one end. The mounting portion 42 
has an L-shaped recess formed by flat surfaces 46 and 48 which are 
perpendicular to one another. The surface 46 is perpendicular to the 
longitudinal centerline of the handle. The surface 48 lies on the 
longitudinal centerline of the handle. Projecting from surface 48 is a 
square peg 50 of substantially the same size and shape as the hole 40 in 
the extension 34 of the mounting portion 32 of the base 26. The peg 50 
extends outwardly from the surface 48 on an axis which is parallel to the 
pivot pins 22, 24, 28 and 30. The peg 50 is adapted to be received in the 
hole 40 with a close fit preventing rotation of the handle relative to the 
base. Two opposite parallel sides of the peg 50 are parallel to the 
surface 46 and the remaining two sides are perpendicular thereto. The 
mounting portion 42 of the handle has opposite flat side surfaces 60 and 
62 which are parallel to the longitudinal centerline of the handle. 
When the handle 12 is secured to the base 26, the handle extends parallel 
to the plane of swinging movement of the arm assembly 14, and parallel to 
the shank 21 of the tool. 
When assembled as in FIGS. 1 and 4-6, the peg 50 is received in the hole 40 
with the surfaces 36 and 48 in flush surface-to-surface engagement and 
with the flat side surface 62 in flush surface-to-surface engagement with 
the flat surface 38 of the body portion of the base 26. The peg 50 and 
hole 40 prevent the handle 12 from rotating relative to the base 26 of the 
arm assembly 14. The engagement of the surface 62 of the mounting portion 
of the handle 12 with surface 38 of the base 26 also prevents rotation of 
the handle 12 relative to the base 26 of the arm assembly 14. The side 
surface 41 of the extension 34 of the base 26 is in flush 
surface-to-surface engagement with the surface 46 of the mounting portion 
42 of the handle to also prevent rotation of the handle relative to the 
base 26 of the arm assembly 14. The handle 12 is parallel to the shank 21 
of the tool in all positions (compare FIGS. 4-6) and parallel to a 
straight line connecting the pivot pins 28 and 30. 
A screw 70 threads through the mounting portion 42 of the handle and has a 
head 72 engaging the base 26 to releasably secure the handle and arm 
assembly together. 
The peg 50 is removable from the hole 40 to disconnect the handle 12 from 
the base 26 so that the handle can be rotated 180.degree. to a second 
position and the peg re-inserted in the hole. This arrangement is shown in 
FIGS. 7 and 8. In this alternate position of the handle, the peg 50 and 
hole 40 prevent the handle 12 from rotating relative to the base 26 of the 
arm assembly 14. The engagement of the surface 60 of the mounting portion 
of the handle 12 with the surface 38 of the base 26 also prevents rotation 
of the handle 12 relative to the base 26 the arm assembly 14. Surface 39 
of the extension 34 of the base 26 is in flush engagement with the surface 
46 of the mounting portion 42 of the handle as a further means of 
preventing relative rotation. Likewise, in this alternate condition, the 
handle 12 is parallel to the shank 21 of the tool. 
The various figures show the flexibility and adaptability of the tool of 
this invention, enabling it to be used in many difficult situations where 
the fastener is not readily accessible but can be reached by the tool of 
this invention.