Improvements in Screw Wrenches or Spanners.
Year: 1897

page_text: Date of Application, 5th Oct., 1897-Accepted, 11th Dec., 1897
COMPLETE SPECIFICATION.
Improvements in Screw Wrenches or Spanners.
I, FRANK STEWART SMITH, Engineer, of 263 Wabash Avenue, Chicago, Cook
County, Illinois, United States of America, do hereby declare the nature of my
invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:
The object of my invention is to provide a simple, economical and efficient screw
wrench adapted to have an easy and rapid adjustment, which is intended to be
an improvement upon the wrench described and claimed in Letters Patent, No.
13900, dated June 23, 1896; and the invention consists in the features, com-
binations and details of construction hereinafter described and claimed.
In the accompanying drawings, Figure 1 is a side elevation of my improve-
ment, shown partly in section; Fig. 2 a transverse section taken on line 2 of
Fig. 1, looking in the direction of the arrow; Fig. 3 a longitudinal sectional
elevation of the sliding jaw, showing a modified construction; and Fig. 4 an
end view of Fig. 3.
In constructing a wrench in accordance with my improvements, I make a
body, portion A, and provide it at cne end with a fixed or immovable jaw a. I
then make a movable jaw B and slidingly mount it on the body portion,
providing it with an encompassing sleeve b that spans and encloses the body
portion of the wrench in such manner that the jaw is prevented from such lateral
movement, but is permitted to have an easy longitudinal movement.
To provide means by which the movable jaw may be operated, I provide a
shaft C, which is mounted in suitable openings in the sliding jaw. In my
preferred construction these openings are elongated, so that the shaft may have
a limited lateral movement for the purposes hereinafter described. The shaft is
provided with a rotatable worm C, which is held between the main portion of the
jaw and the lug 2, so that it can have a free rotary motion, but no longitudinal
movement.
In order to hold the shaft with its worm in operative engagement and permit
such worm to be drawn from its operative engagement, I provide the shaft at
each end with diametrical openings or recesses, and insert therein helical coiled
springs that have one end resting against the interior surface of the openings
in the jaw and the other against the bottom of the diametrical openings of the
shaft, in such manner that when the shaft is free to operate it forces the teeth
of the worm into engagement with the teeth a¹ of the wrench body and permits
the revolution or rotation of the worm and adjustment of the jaw.
Inspecting Figs. 1 and 2 of the drawings, it will be seen that the helical coiled
spring-to the left of Fig. 1-not only acts to assist in keeping the worm .n
operative engagement, but also assists in preventing the unlocking of the parts
that is, the shaft cannot be disengaged from the worm until this helical coiled
spring is forced down below its surface.
In Figs. 3 and 4 all of the parts are constructed the same as described in
connection with Figs. 1 and 2, with the exception that the shaft C is made oval
or elliptical-shaped at its bearing portions, and the perforations or openings 4
037

page_text: are made perfectly round. This accomplishes the same result as shown in
Fig. 1—that is, it permits the necessary lateral movement of the shaft and
consequent rapid adjustment of the jaw. In order to lock the parts in place,
however, the lug 62 of the jaw is recessed at 65 to allow the helical coiled spring
to enter the same.
.j
The advantages of my improvement are, that the parts may be manufactured
very economically, and that a less number of parts is required than in my
former improvement. Further, the parts are more readily assembled and easily
taken apart for the purposes of repair or renewal.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what I
claim is;
1. In a screw wrench, the combination of a body portion provided with teeth
and a jaw portion, a jaw slidingly mounted thereon, a worm shaft laterally
movably mounted in the sliding jaw and provided with diametrical openings --
one at each end thereof, and helical coiled springs at each of such openings in
the worm shaft for holding the parts in operative engagement and locking them
together, substantially as described.
2. In a screw wrench, the combination of a body portion provided with teeth
and rigid jaw, a second jaw slidingly mounted thereon and provided with
elongated openings, a worm shaft laterally movably mounted in the sliding jaw
and provided with diametrical openings, one at each end thereof, and a helical
coiled spring in each of said openings for holding the parts in operative engage-
ment and locking the same together, substantially as described.
Dated this 5th day of October 1897.
HASELTINE LAKE & CO.
45 Southampton Buildings, London, W.C. Agents for the Applicant.