IMPROVEMENTS
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said John Thomas Mitchell at
the Office of the Commissioners of Patents on the 6th July 1882.
JOHN THOMAS MITCHELL, of Mere, in the County of Wilts,
TENSION COUPLINGS;"
"IMPROVEMENTS IN
My invention has for its object to disconnect the tractive force from the load,
or the load from the support from which it is suspended, while the apparatus is in
action, and without loss of time. It is applicable as a coupling or attachment for
vehicles, ships boats and similar objects. For this purpose the apparatus comprises
two parallel rods one of which has at its coupling end a lateral projection resting
with its oblique base or face on a correspondingly oblique face formed on a lateral
projection of the second rod, so that by pulling the two rods in opposite directions
(from each other) the projection of the first rod slides over the oblique face of the
second rod, so as to get disengaged from the latter. Along the second rod is guided
a movable slide, one end of which passes over the coupling end of the first bar,
while the other end is provided with a handle or with an eyelet for attaching a
cord by which the slide may be drawn out of contact with the first bar. A strap
fixed to the sides of the second bar and passing over the end of the movable slide,
serves to retain the coupling end of the first bar between the slide and the end of
the second bar, so as to prevent it from sliding sideways out of contact with the
oblique face of the latter, as long as the end of the slide remains under the strap,
in which position it is retained by a spring. For disconnecting the two bars while
a tractive force acts upon them it is sufficient to draw the slide back, so that its
end gets out of the contact with the end of the first bar, after which the latter is
automatically drawn sideways by the tractive force transmitted by the coupling.
The spring is preferably a helical spring placed in a recess between the two
coupling bars,

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said John Thomas Mitchell in the Great Seal Patent Office on the
6th January 1883.
"
JOHN THOMAS MITCHELL, of Mere, in the County of Wilts IMPROVEMENTS IN
TENSION COUPLINGS"
My invention has for its object to disconnect the tractive force from the load,
or the load from the support from which it is suspended, while the apparatus is in
action, and without loss of time. It is applicable as a coupling or attachment for
vehicles, ships boats and similar objects. For this purpose the apparatus comprises
two parallel rods one of which has at its coupling end a lateral projection resting
with its oblique base or face on a correspondingly oblique face formed on a lateral
projection of the second rod, so that by pulling the two rods in opposite directions
(from each other) the projection of the first rod slides over the oblique face of the
second rod, so as to get disengaged from the latter. Along the second rod is
guided a movable slide, one end of which passes over the coupling end of the first
bar, while the other end is provided with a handle or with an eyelet for attaching
a cord by which the slide may be drawn out of contact with the first bar. A
strap fixed to the sides of the second bar and passing over the end of the movable
slide, serves to retain the coupling end of the first bar between the slide and the
end of the second bar, so as to prevent it from sliding sideways out of contact with
the oblique face of the latter, as long as the end of the slide remains under the
strap, in which position it is retained. by a spring. For disconnecting the two bars
while a tractive force acts upon them it is sufficient to draw the slide back, so that
its end gets out of contact with the end of the first bar, after which the latter is
automatically drawn sideways by the tractive force transmitted by the coupling.
The spring is preferably a helical spring placed in a recess between the two
coupling bars.
The accompanying drawing Figs. 1 to 3 shows a method of carrying my invention
into practice, Fig 1 being a vertical section of a traction-coupling, with the
releasing bolt in action, Fig 2 the same with the releasing bolt disengaged, and
Fig. 3 a plan of the coupling.
The points of application for the tractive force and resistance, are respectively
the ring A¹ and the wooden shaft E, of which only the front part is shown. A is
the releasing bolt provided at the front end with a ring A' and at the back with a
tongue a. B is the sliding wedge connected with a ring b and pushed forward
under the strap or bridge-piece C by a spring & mounted on a spindle D.
c is a base-plate rigidly connected or made in one piece with the strap C, and
attached to the wooden shaft E, the front of which is further armed with a
staple F.
The tractive force acting on the ring A¹ in the direction of the arrow by means
of a chain or equivalent appliance, tends to draw the shaft E forward, as long as
the oblique front surface at of the tongue a is held down against the corresponding
abutment a² by the wedge B, under the influence of the spring d.
But as soon as the ring b is pulled back in the direction of the arrow by a small
releasing chain attached to it, the wedge B recedes and allows the tongue a to
slide upward into the position represented by. Fig 2, and out of the strap C,
whereby the connection between A and E is broken.
-
I do not, however, restrict myself to the particular shape of coupling represented'
by the drawing as an example, but wish it to be understood, that the details of
construction may be varied to suit different purposes.
What I claim is :-
-
1. The combination of a releasing bolt acted upon by a tractive force, and having
an oblique face or tongue, with a shaft or rod connected with the load or resistance,

page_text: and having an oblique face or projection corresponding to that of the releasing
bolt, a movable slide or wedge adapted to lock the releasing bolt and connected
with a releasing chain or equivalent device, and a strap adapted to hold together
the releasing bolt and movable slide, substantially as and for the purposes
described.
2. The combination of releasing bolt A actuated by the tractive force with
slide B, strap C, spring & and plate o, connected with the load, substantially as and
for the purposes described.
In witness whereof I the said John Thomas Mitchell have hereunto set
my hand and seal this fourth day of January A.D. 1888.
JOHN. THOMAS, MITCHELL (LA)