Improvements in or connected with Screw Fastenings.
Year: 1896

page_text: Date of Application, 2nd Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in or connected with Screw Fastenings.
We, MORGAN LESLIE TUCKER, of Crown Works, Chesham, in the County of
Buckingham, Wood Worker, and PETER CHARLES BRACHI, of Brook House, South-
gate, in the County of Middlesex, Gentleman, do hereby declare the nature of
this invention to be as follows:-
As is well known many of the parts of machinery and of apparatus of various
kinds are connected together by means of screw bolts, or by screw-bolts and nuts.
In some cases the parts have to be frequently separated from one another and
connected together again, and it is often desirable that this operation shall be
effected as quickly and easily as possible. When screw bolts or screw-bolts and
nuts are employed the tightening down and slackening of the nuts on the bolts
or of the bolts in their nuts or in the other internally screw-threaded parts adapted
to receive them not only occupies considerable time, but involves a great deal of
muscular exertion to overcome the frictional resistance, especially when the parts
are required to be firmly pressed together. The object of the present invention is
to provide a screw fastening which can be quickly and easily tightened up or
slackened without screwing the nut or the head of the bolt so tightly against the
parts to be connected as has been heretofore necessary.
For this purpose we make the nut or the head of the bolt, as the case may be,
with a pin or trunnion standing out laterally on each side thereof; and on each
of these pins or trunnions we mount, so as to be free to turn thereon, an eccentric
or cam, the two eccentrics or cams being preferably connected together by means
of a bar or other suitably shaped piece of metal adapted to serve as a handle or
lever by which the said eccentrics or cams can be turned on the aforesaid pins or
trunnions. The eccentrics or cams are so shaped that when turned into one
position they do not extend beyond the bearing surface of the nut or head to which
they are applied, but when turned into another position they extend beyond such
bearing surface.
It will now be understood that when the eccentrics or cams are placed in the
first position above mentioned, the nut, or the head of the bolts, as the case may
be, can be screwed down until its bearing surface comes in contact with the part
that is to receive the pressure, then by turning the eccentrics or cams into the
second named position they are caused to exert a wedging action which presses
the two parts of the machine or apparatus firmly together without the necessity
of screwing up the nut or bolt tightly as would otherwise be necessary. On again
turning the eccentrics or cam in the reverse direction the parts are slackened, and
the nut or bolt, as the case may be, can be easily unscrewed again.
In some cases where the pressure to be exerted is comparatively small, the pin
or trunnion and eccentric or cam on one side of the nut or bolt head may be
dispensed with, but in most cases an eccentric or cam on each side is preferable.
Dated this 2nd day of October 1806
M. L. TUCKER,
P. C. BRACHI,
Per W. H. Beck,
115 Cannon Street, London, E.C., Agent.

page_text: ovements in or connected with Screw Fastenings.
We, MORGAN LESLIE TUCKER, of Crown Works, Chesham, in the County of
Buckingham, Wood Worker, and PETER CHARLES BRACHI, of Brook House, South-
gate, in the County of Middlesex, Gentleman, do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
As is well known many of the parts of machinery and of apparatus of various
kinds are connected together by means of screw bolts, or by. screw-bolts and nuts.
In some cases the parts have to be frequently separated from one another and
connected together again, and it is often desirable that this operation shall be
effected as quickly and easily as possible. When screw bolts, or screw-bolts and
nuts are employed the tightening down and slackening of the nuts on the bolts or
of the bolts in their nuts or in the other internally screw-threaded parts adapted
to receive them not only occupies considerable time, but involves a great deal of
muscular exertion to overcome the frictional resistance, especially when the parts
are required to be firmly pressed together. The object of the present invention is to
provide a screw fastening which can be quickly and easily tightened up or slackened
without screwing the nut or the head of the bolt so tightly against the parts to
be connected as has been heretofore necessary.
And in order that the said invention may be fully understood, we will proceed
to describe the same with the aid of the accompanying sheet of drawings in which
Figure is a side elevation of a screw fastening constructed in accordance with
our invention, Figure 2 a plan of same, and Figure 3 an elevation showing the
invention applied under somewhat different circumstances.
For the purposes of our invention we make the nut A of the bolt or stud B with
a pin or trunnion C standing out laterally on each side thereof and on each of
these pins or trunnions we mount, so as to be free to turn thereon, an eccentric
or cam D, the two eccentrics or cams being preferably connected together by means
of a bar E or other suitably shaped piece of metal adapted to serve as a handle or
lever by which the said eccentrics or cams D can be turned on the aforesaid pins
or trunnions C. The eccentrics or cams D are so shaped that when turned into
one position, such as that shown by dotted lines for example, they do not extend
beyond the bearing surface of the nut A to which they are applied, but when
turned into another position, such as that shown in full lines, they extend beyond
such bearing surface, as shown in Figure 1.
It will now be understood that when the eccentrics or cams D are placed in the
first position above mentioned, namely that shown in dotted lines, the nut A can
be screwed down on the bolt or stud 13 by the handle or lever E until the bearing
surface of the said nut comes in contact with the part F that is to receive the
pressure; then by turning the eccentrics or cams 1 by means of the handle or
lever E into the second position, namely that shown in full lines, they are caused
to exert a wedging action which presses the two parts F and G of the machine or
apparatus firmly together without the necessity of screwing up the nut tightly as
would otherwise be necessary. On again turning the eccentrics or cams D in the
reverse direction the parts are slackened, and the nut can be easily unscrewed again.
In the drawings the part G represents in section the flange of a vessel of circular
or other shape and F part of a cover for the same, H representing an indiarubber
or other jointing washer interposed between the cover and flange; and our improved
screw fastening is shown applied to the purpose of pressing the cover F to the
flange G by the bolt or stud B; but it will be understood that what is shown is
merely by way of example, as the fastening is applicable to any purpose v
where

page_text: parts of machinery or apparatus require to be held together provided sufficient
pressure can be applied through the medium of the eccentrics or cams, and that
the fastening is otherwise suited to the purpose in view.
It will be understood that in cases where screws or bolts are screwed into tapped
holes the heads of such screws or bolts are provided with the pins or trunnions C
for carrying the eccentrics or cams 1) as shown in Figure 3.
In some cases where the pressure to be exerted is comparatively small, the pin
or trunnion and eccentric or cam on one side of the nut or bolt may be dispensed
with, but in most cases an eccentric or cam on each side is preferable.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, we declare that what
we claim is:
First. In a screw-fastening, providing the nut of the screw-bolt or stud with a
lateral pin or trunnion on one or both sides thereof, and mounting on such pin or
trunnion, or on both pins or trunnions when two are employed, an eccentric or
cam provided with an operating handle or lever, substantially as described.
Second. In a screw-fastening, providing the head of the screw-bolt with a lateral
pin or trunnion on one or both sides thereof, and mounting on such pin or trunnion,
or on both pins or trunnions when two are employed, an eccentric or cam provided
with an operating handle or lever, substantially as described.
Third. A screw-fastening constructed and operating, substantially as described.
100-
M. L. TUCKER,
P. C. BRACHI,
Per W. H. Beck,
115 Cannon Street, London, E.C., Agent.