Year: 1887

page_text: Date of Application, 21st Nov., 1887
Complete Specification Left, 17th Aug., 1888
Complete Specification Accepted, 5th Oct., 188
I, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake and Co. Patent Agents,
Southampton Buildings, in the County of Middlesex, do hereby declare the nature of
this invention to be as follows :-
This invention relates to door-checks or devices for preventing the slamming of
doors, and the object of the present improvements are to impart a double stroke to
the piston for one motion of the door; to produce a check or device adapted for both
right and left hand doors, and in general to simplify the construction and improve
the efficiency of the apparatus.
In this improved door check, the cylinder is pivoted at one end to a bracket which
is secured to the door-casing in such a manner as to clear the door.
The piston head is secured upon the piston rod by a slot and pin connection so that
the piston head shall have a limited longitudinal play thereon, whereby its conoidal
end, which serves as a valve, is pressed upon and lifted from the central valve seat in
the piston head, the said piston-rod being flattened on opposite sides to permit the
passage of air through the piston head during the backward or outward stroke of the
piston. Instead of constructing the vent in the cylinder or in a special passage through
the piston head, I form a slot in the conoidal end of the piston rod, that is to say, in
the contact surface of the valve and valve seat, thus providing a small vent through the
said contact surfaces when the valve is pressed against its seat. This vent can be
constructed at a very trifling cost and by being formed in the conoidal or tapering
end of the piston rod which acts as a valve, the air passes through it, or by it, in
either direction and the vent being removed from the valve seat upon every return
stroke of the piston is less liable to become clogged than a vent which is at all times
surrounded by a solid wall.

page_text: The bracket secured to the door casing is provided with a projecting end to which
is pivoted an operating lever, and to the latter is coupled the end of the piston rod.
The long end of this lever has pivoted to it a link which is pivotally connected to a
bracket secured to the door. The pivotal post of this bracket is preferably formed of
a separate piece and is secured to its bracket by means of a screw, the hole for the
said screw, in the post being eccentric or to one side of the pivot for the link, so that
upon loosening the screw and swinging the post partially around it, the pivot may be
adjusted and secured at varying distances from the face of the door.
In order to provide for a still further adjustment the flange of the last named
bracket may be provided with two or more holes through which to pass the said
screw.
The mechanism thus far described completes the check or buffing mechanism and
may be used in connection with any ordinary door-closing spring.
prefer however
to connect the door-closing spring to the short end of the lever and 1 sometimes
employ a coiled spring arranged around the axis of a pair of toggle-arms, the ends of the
wire forming the spring being bent out so as to bear upon each of the said arms. One
of the toggle-arms is hooked upon one of the pivotal studs of the main bracket and
the other arm is connected by a series of links to the short end of the aforesaid lever.
The cylinder is elevated above the said lever so that the said lever may swing under
the cylinder.
Upon opening the door the bracket on the said door, will, through the aforesaid
link, push upon the long end of the lever so as to draw the piston outwardly, the
cylinder meantime swinging upon its pivot. When the door has been opened so as
to be at an angle of about forty-five degrees to the casings, the lever will stand at
about right angles thereto and the piston will be drawn outwardly to the full extent of
its stroke. Upon the further movement of the door the piston is pushed inwardly
thereby cushioning the door in its backward movement. Upon releasing the door,
the closing spring acts to return the door, while the lever pulls the piston outwardly,
thereby opening the valve so that no air is compressed within the cylinder until after
the door has passed a certain point. This permits the door to close quickly through
the greater part of its stroke and to be suddenly arrested by the formation of an air
cushion within the cylinder during the latter part of its stroke just in time to prevent
the door from slamming. The device may be changed from the position described to
adapt it for use upon a different handed door, by simply swinging the lever around
so that the end to which the piston rod and link are pivoted will point in the opposite
direction. If the door-closing spring herein described is used in connection therewith,
one of the toggle-arms must be unhooked from one of the pivotal studs of the bracket
and hooked upon the like stud at the opposite side of the said bracket.
My bracket has considerable projection from the casing, and the pivot to which the
cylinder is pivoted and the fulcrum of the lever are in a line which is substantially at
right angles to the face of the door casing, I am thus enabled to impart a double
stroke to the piston, for one movement of the door, provided the door is opened beyond
a given point.
Dated this 21st do
זג
1004
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Devices for Preventing the Slamming of Doors.
I WILLIAM ROBERT LAKE, of the firm of Haseltine Lake & Co., Patent Agents,
Southampton Buildings in the County of Middlesex 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 :-
This invention relates to door-checks, or devices for preventing the slamming of
doors. The objects of the present improvements are to construct the device with a
piston which works in a cylinder and to which a double stroke will be imparted for
one motion of the door, that is to say, in the opening and in the closing of the door
to produce a door-check or device adapted for both right and left hand doors, and in
general to simplify the construction and improve the efficiency of the apparatus.
In the accompanying drawing
Figure 1 is a front elevation showing a portion of a door and casing or frame with
the improved door-check attached thereto.
Figure 2 is a plan of the same.
Figure 3 is a plan showing the parts in the position they assume when the door is
open.
Figure 4 is a vertical central section on the line x Figure 1 showing the bracket
by which the check is connected to the door.
Figure 5 is a longitudinal central section of the piston-head and a portion of the
piston-rod.
Figure 6 is an end view of the piston rod.
Similar letters indicate corresponding parts throughout the drawing.
A is the door, B the door-frame or casing, C is a cylinder pivoted at a to a
bracket D which is secured to the door-casing B in such a manner as to clear the
door A. The piston head E Figure 5 is secured upon the piston rod 6 by a slot and
pin connection so that the piston-head shall have a limited longitudinal play upon the
rod, and its conoidal end, which serves as a valve will be pressed upon and lifted
from the central valve-seat in the piston-head in the inward and outward strokes of
the piston. The said piston-rod is flattened on opposite sides to permit the passage
of air through the piston head during the backward or outward stroke of the piston.
Instead of constructing the vent in the cylinder or in a special passage through the
piston-head, I form a slot or groove c in the conoidal end of the piston rod, that is to
say, in the contact surface of the valve or in the contact surface of the valve-seat thus
providing a small vent through the said surfaces when the valve is pressed against its
seat. This vent can be constructed at a very trifling cost and by being formed in
the conoidal or tapering end of the piston-rod which acts as a valve, the air passes
through it, or by it, in either direction and the vent, being removed from the valve-
seat upon every return stroke of the piston is less liable to become clogged than a
vent which is at all times surrounded by a solid wall.

page_text: The bracket D secured to the door-frame or casing B is provided with a projecting
end to which is pivoted at F1 an operating lever F; to this lever is coupled at 6 the
outer extremity of the piston-rod b. The long end of this lever F is coupled by a
link G to a bracket H secured to the door. The pivotal post d of this bracket is
preferably formed of a separate piece and secured to the bracket H by means of a
screw e the hole for the said screw in the post d being eccentric or to one side of the
pivot for the link so that upon loosening the screw and swinging the post partially
around it, the pivot may be adjusted and secured at varying distances from the face
of the door..
In order to provide for a still farther adjustment the flange of the last named
bracket H is sometimes provided with two or more holes through which to pass the
said screw e.
The mechanism above described completes the check or buffing mechanism and may
be used in connection with any ordinary door-closing spring. I prefer, however,
to connect the door-closing spring to the short arm of the lever F. I sometimes
employ a coiled spring J arranged around the axis of a pair of toggle-arms f, the
ends of the wire forming the spring being bent out so as to bear upon each of the
said arms. One of the said toggle arms is hooked upon one of the pivotal studs h of
the bracket B and the other arm is connected by a series of links to the short end of
the lever F. As will be seen by reference to Figure 1 the cylinder () is elevated
above the lever F so that the said lever may swing under the cylinder.
Upon opening the door, the bracket H through the aforesaid link G pushes upon
the long end of the lever F so as to draw the piston outwardly, the cylinder meantime
.swinging upon its pivot a. When the door has been opened so as to be at an angle
of about forty-five degrees to the door-frame or casing the lever F will stand at
about right angles thereto and the piston will be drawn outwardly to the full extent
of the stroke as shown in dotted lines in Figure 3. Upon the further movement of
the door, the piston is pushed inwardly thereby cushioning the door in its backward
movement. Upon releasing the door, the closing spring Jacts to return the door,
while the lever F pulls the piston outwardly, thereby opening the valve so that no
air is compressed within the cylinder until after the door has passed a certain point.
This permits the door to close quickly through the greater part of its stroke and to be
suddenly arrested by the formation of an air cushion within the cylinder during the
latter part of its stroke, just in time to prevent the door from slamming. The
device may be changed from the position described to adapt it for use upon a door
opening in a different direction by simply swinging the lever around so that the
end to which the piston rod and link Gare pivoted will point in the opposite direction.
If the door closing spring herein described is used in connection therewith one of the
toggle-arms must be unhooked from one of the pivotal studs of the bracket D and
hooked upon the like stud at the opposite side of the said bracket.
My bracket has considerable projection from the door-frame or casing, and the
pivot a to which the cylinder is pivoted and the fulcrum of the lever F are in a line
which is substantially at right angles to the face of the door frame or casing, I am
thus enabled to impart a double stroke to the piston, for one movement of the door
provided the door is opened beyond a given point.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me by
my foreign correspondent I wish it understood that I am aware that door-checks
have been constructed with a cylinder and a piston operated by a lever and pivoted
link, the said lever and link being mounted upon brackets secured respectively to
the door and its frame or casing; and that in some cases, the cylinder has been
pivoted. I am also aware that a pneumatic door check has been devised consisting
of a stationary cylinder; a piston whose rod is provided with a slotted cross-head, an
operating angle lever having a pin working in the slot of the said cross-head, a door-
closing spring connected with the axle of the operating lever and a pair of toggle
levers having one arm or link pivoted to a stationary bracket and the other arm or

page_text: link to one end of the operating lever. I therefore do not claim generally or
irrespectively of my improvements herein set forth a door check provided with a
cylinder and piston. I am not aware, however, that it has heretofore been proposed
to construct a door-check in such a manner that the piston will have a double
stroke imparted to it in each movement of the door in opening and closing; and
1 claim :-
First. A door-check wherein a piston and cylinder are so arranged that, in the
opening and in the closing of the door, a double stroke will be imparted to the said
piston, as, and for the purposes, above specified.
Second. The valve and the valve-seat in the piston-head provided on one or both
of their contact surfaces with a vent or slot and connected with the operating
mechanism, substantially as described and for the purposes specified.
Third. The combination of the cylinder and piston with the operating lever, the
link, the bracket, and the eccentric pivotal post secured to the said bracket, substan-
tially as described and for the purpose specified.
Fourth. The combination of the link and its bracket, the cylinder and piston
pivoted to another bracket and the operating lever having its fulcrum in front of the
pivot of the said cylinder on a line substantially at right angles to the face of the
door-frame or casing, substantially as described and for the purpose specified.
Fifth. The combination of the link and its bracket, the operating lever pivoted to
another bracket and having its long end coupled to the outer end of the said link, the
cylinder and piston pivoted at one end to a stationary bracket and coupled at the
opposite end to the long end of the said operating lever, and the door-closing spring
connected with the short end of the said operating lever, substantially as described
and for the purpose specified.
Sixth. The improved door-check consisting of the parts constructed and combined
substantially as described with reference to the accompanying drawing.
Dated this 15th day of An 1820
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.