Year: 1885

page_text: I ALFRED JULIUS BOULT of 323 High Holborn, in the County of Middlesex,
Engineer, do hereby declare the nature of this invention (a communication from
Gilbert R. Elliott of New York, United States of America) and in what manner
the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This invention relates to pneumatic door checks and mechanism by which they
are made more durable and lasting, simpler, in their construction, cheaper in first
cost, and more readily manipulated and easy of repair.
The object of the invention is to prevent doors or gates from slamming, and
therefore prevent the violent noise incident thereto, and also prevent breakage of
glass of doors which very often occurs from the violent shutting thereof by gusts of
wind or otherwise.
To these ends this invention consists!
In a door check, having its piston rod mounted at its rear end on a friction
joint or hinge.
In a spring toggle joint mechanism whereby when the door is shut, the springs
and toggle connections will force the piston and buffer to resume proper position
for the next closing movement of the door.
In means for preventing the rattling or shaking of the door from any cause, as
such shaking is very annoying and disagreeable, the movement of toggle and spring
also assists in opening the door after the knob is turned all of which will be more
fully hereinafter described and pointed out in the claims.
Heretofore in pneumatic door checks have been made with connections which
were fastened both to the door casing and door, which rendered the door hard to
open, and otherwise awkward to handle, but with this device the door is perfectly
free the same as if there were no checks, either whether the check be on the door
or on the casing, although it may be adapted to either with equally results.
The piston rod in door checks has, also, been mounted on a hinge or joint but in
such construction it was necessary to provide other means to hold it in any desired
position. With my friction hinge such auxiliary devices are unnecessary and the
piston, as it is withdrawn from the cylinder will assume the correct position to
re-enter the cylinder when the door is closed and will be automatically held in
such position.
Referring to the drawings in which the same letters indicate like parts in all
the fianres

page_text: Fig. 1 is a longitudinal section through a cylinder piston, and piston rod, showing
the piston rod mounted on a friction joint.
Fig. 2 is a view in side elevation of a friction joint and rear end of the
piston rod.
Fig. 3 is a top plan view of the device applied to a door the door being open.
Fig. 4 is a similar view, the door being closed.
Fig. 5 represents a side elevation of this improved toggle door check, the dotted
lines showing the position of the toggle and when the door is in a closed position.
Fig. 6 is an end elevation of the same.
Fig. 7 is a vertical longitudinal section through the entire apparatus.
Fig. 8 is an enlarged detailed view of the piston head.
Fig. 9 is an enlarged view of the piston head which also shows the stuffing box
for the piston rod, spring clearly showing the spring fingers for setting out the
packing.
"
Fig. 10 is a detailed view of the toggle joint, and spring arm connection.
Fig. 11 is a detailed view of one of the cylinder heads.
Fig. 12 shows a check in position ready for use, also an angular supplementary
buffer which provides for the angle of the door so that the check comes in contact
with the door on a straight line.
.
Referring to the drawings by letters, A is the cylinder having open flaring
end B. C is the closed head of the cylinder and D the piston having cupped
head E. The cylinder head has air apertures d, d, to admit air when the piston is
being withdrawn and a slotted screw escape opening to allow of the gradual escape
of the air when the piston is entering the cylinder. The openings, d, are closed,
when the piston is entering the cylinder, by a packing valve, e, b are flanges by
which the cylinder can be attached. F is the frame of the friction joint or hinge
in which the rear end of the piston rod is mounted. The screw h, forms the pintle,
and the friction is created by a cup shaped spring, 9. A washer is interposed
between the piston rod and spring to regulate friction. When the door is opened
the piston is wholly withdrawn from the cylinder and by virtue of its friction
joint, the rod assumes, just as it leaves the cylinder, the correct position to re-enter
it when, in closing the door, it reaches its mouth. No adjustment of any kind is
necessary, nor are any auxiliary devices.
i, is the frame and j is the door.
F is the cylinder of the door check which may preferably be made of drawn
tubing, G, H are the cylinder heads which may be secured in any approved manner,
I is the piston head and J the piston rod, the cylinder head H is of very peculiar
construction and is cast with two wing flanges, k, l, and two bifurcated hinge
plates, m, n, integral therewith.
The flanges, k, l, are for the purpose of securing the door check to the casing or
the door as the case may be, and the bifurcated hinge pieces are connections for the
toggle joint levers, the piston rod J, carries on one of its ends the piston, and on its
other end, a cross-head K which cross-head has a central bore for the piston rod,
a pair of bifurcated hinged lugs, o, p, and two upper projecting lugs q, r in the
latter of which is placed an anti-friction roller, 8, which roller prevents the abrasion
of the door while in contact therewith.
The toggle arms L, M, are formed at one end with the hinge link or eye which
engages with bifurcated hinged flanges L, K, H, J, respectively, and at their central
joint, N, O, with laterally projecting hinge flanges, between the inner flanges N
and upon the pintle t, spiral springs P, the end of which bear against the end of the
opposite hinge N, O, are located in such manner that the resiliency of the spring
serves to bring the toggle lever to an elevated position, but of course out of a
straight line, as may be seen in Fig. 5, the object being to bring the buffer back to
a position to receive the shock of the door when it is violently shut, thus it will be
seen that when the door strikes the buffer or check, the latter will gently yield
to the force of the door, and permit it to shut without jar or noise the operation of
which will be more fully hereinafter described.

page_text: The piston head and packing is made of a metallic disc, having serrations around
its periphery, the divisions between the serrations form springs by which the
packing is kept tight.
The operation of the mechanism is as follows:
The flanges k, l, are secured to the door or the casing as may be preferred, the
buffer being arranged to strike either, so that when the door is slammed violently to
it strikes the buffer the force being imparted to the piston rod and piston the latter
yields displacing the air in the cylinder which forms a cushion and permits the
door to gradually advance to its place in the door frame or casing without noise or
shock, the toggle lever taking the position shown in dotted lines. When the door
is again opened the spiral springs around the pintle acts upon the toggle levers
which are connected to the cross-head on the end of the piston rod and the
cylinder head and forces out the piston and rod to meet the action of the door from
being again closed.
An additional function of the spring toggle is to assist in opening the door as
the springs commence to act, just as soon as the door fastening is released, in the
door checks now in use it requires considerable effort to open the door the effort
being exerted in displacing the air in the opposite end of the cylinder, all of which
will be readily understood by persons familiar with this class of inventions.
It is evident that modifications may be made in the construction and arrangement
of the parts without departing from the spirit and scope of this invention.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed as communicated
to me by my foreign correspondent, I declare that what I claim is
1. The combination, substantially as described, of a cylinder, open at one end
and having an air aperture at the other, a piston adapted to reciprocate the
cylinder, and a spring friction hinge upon which the piston rod is mounted as
Bet forth.
2. In a door check, the combination of the cylinder a piston, and a piston rod, the
latter being mounted at its outer end on a friction hinge or joint, substantially as
set forth.'
3. A pneumatic door check and piston rod of which is provided with spring
toggle levers acting in combination to draw the piston to one end of the cylinder
for the purpose substantially as described.
4. The combination in a pneumatic door check having a cylinder and piston, of
the rod provided with a cross-head as described the toggle levers and the springs
all being arranged to operate as set forth.
5. A pneumatic door check having one of its cylinder heads provided with
fastening devices or flanges a stuffing box and bifurcated hinge lugs in combination
with the spring toggle levers in the manner and for the purpose set forth.
6. In a pneumatic door check, the combination of the piston, the spring being
arranged on pintles working on flanges formed on the toggle joint, the piston
rod, and the spring toggle levers, arranged for joint operation, substantially as
described.
7. The combination in a door check having the spring toggle lever as described
of the cross head provided with the antifriction roller and with the buffers on the
door for contact with the said rollers, whereby their combined action lessens the
shock of the door when violently closed; as set forth.
W. P. THOMPSON & BOULT,
Agents.