Improvements in Door Checks.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Door Checks.
I, BENJAMIN TURNER, of 50, Bartholomew Close, London, E.C., Engineer, do
hereby declare the nature of this invention to be as follows:-
The object of this invention is to provide an improved check action for door
springs, which can be applied in connection with any construction of such springs,
whether the door with which same is used be arranged to open in one only or in
both directions.
In carrying out the present invention, when the apparatus is to be used in
connection with a door opening in both directions, I mount a cam on the pin on
which the door is carried, such cam having teeth at a suitable part of its periphery
which engage with corresponding teeth on a pivotted lever, the latter having
three arms and being made substantially of T shape with its teeth situated opposite
the junction of the cross bar with the other arm and arranged concentrically with
the pivot on which the lever turns, which is situated at such junction. The two
oppositely extending arms of this lever are provided beneath with pins which are
so situated when the lever has been turned in either direction by the engagement
of the teeth during the opening of the door as to enter openings in the sides of the
cam above referred to, such cam being provided with a circular groove on its upper
surface into which such pins enter by the further movement of the door. The
third arm of the lever is connected by any suitable means with the piston rod of
an air or liquid cushioning cylinder of any desirable construction, which is pivotted
in the frame of the apparatus so that it can turn to accommodate itself to the
position of the lever as the latter is actuated.
The operation of the apparatus is as follows:-When the door is opened the
teeth of the grooved cam by gearing with those of the three-armed lever cause the
latter to turn on its pivot, so bringing the pin on one of its two oppositely extend-
ing arms opposite the opening to the groove of the cam, and at the same time the
third arm of the lever acts on the piston rod of the air or liquid cushioning
cylinder so as to draw the piston in same forward, air or liquid being allowed to
enter the cylinder behind such piston by means of a suitable valve. By the time
the forward movement of the piston has been completed the pin on one of the two
cross arms of the lever will have entered the groove in the cam, so that on the
further opening of the door such pin will travel in the groove, and the lever will
thus be prevented from returning to its normal position under the action of a
vacuum which might possibly be formed in the air or liquid cushioning cylinder
after the teeth of the cam and lever have become disengaged, and which would
tend to draw the piston back and with it the lever to which as above stated it is
pivotted. When the door is allowed to close it will turn freely until the pin on
the arm of the lever has left the groove in the cam, when the teeth of the cam
and lever will again engage and the latter acting on the piston rod of the air or
liquid cushioning cylinder will through the pressure of air or liquid on the back of the
piston ensure the door closing without jar or shock.
Although I have described this invention as applied in connection with a door

page_text: opening both ways it will readily be seen that it can be applied to a door opening
in one direction only.
It will also be understood that any suitable arrangement of door spring may be
used in connection with the apparatus above described, such for instance as that
referred to in the Specification of my prior Patent No. 16068 dated 6th December
1884, or the door spring described in the Specification of my prior Patent No. 11961
dated 3rd September 1887.
Dated this 16th dow of Cantarhan 1007
improvements in Door Checks.
I, BENJAMIN TURNER, of 50, Bartholomew Close, London, E.C., Engineer, 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:
The object of this invention is to provide an improved check action for door
springs, which can be applied in connection with any construction of such springs,
whether the door with which same is used be arranged to open in one only or in
both directions.
In carrying out the present invention, when the apparatus is to be used in con-
nection with a door opening in both directions, I mount a cam or part on the pin
on which the door is carried, such cam or part having teeth at a suitable point of
its periphery which engage with corresponding teeth on a pivotted lever, the latter
having three arms and being made substantially of T shape with its teeth situated
opposite the junction of the cross bar with the other arm and arranged concen-
trically with the pivot on which the lever turns, which is situated at such junction.
The two oppositely extending arms of this lever are provided beneath with pins
which are so situated when the lever has been turned in either direction by the
engagement of the teeth during the opening of the door as to enter openings in the
sides of the cam or part above referred to, such cam or part being provided with
a circular groove on its upper surface into which such pins enter by the further
movement of the door. The third arm of the lever is connected by any, suitable
means with the piston rod of an air or liquid cushioning cylinder of any desirable
construction, which is pivotted in the frame of the apparatus so that it can turn
to accommodate itself to the position of the lever as the latter is actuated.
But in order that my invention may be fully understood I will now proceed
to describe same by the aid of the accompanying sheet of drawings which shows
such invention applied to a door capable of opening in opposite directions (i.e. both
inwards and outwards), and in which
Fig. 1 is a vertical section showing the parts in the positions they occupy when
the door is closed.
Fig. 2 is a plan view of Fig. 1, and
Fig. 3 a similar view, but with the parts in the positions they occupy when the
door is open or partly open.
In these drawings A is the part mounted on the pin B on which door C is carried,
and which has teeth a formed thereon at a suitable point in its periphery, such
teeth engaging with corresponding teeth d on a pivotted lever of T shape with
three arms D. D'. D², and having such teeth formed opposite the junction
of the arms D1, D2, with arm D, and arranged concentrically with pivot d³ on
which the lever turns. The arms D¹, D³, of the lever are provided. beneath with

page_text: pins.,, so situated that when the lever has (by the engagement of the teeth a
of part A and teeth d of lever D during the opening of the door) been turned in
either direction, one of same will be in a position to enter a circular groove a¹
formed to receive same in part A, and which groove it will enter on the further
movement of the door. The third arm I of the lever is suitably connected with
the piston rod E of the air or liquid cushioning cylinder E', which is pivotted at e
to the frame X of the apparatus so that it can turn to accommodate itself to the
position of the lever as same is turned. is the valve for allowing air or liquid
to enter behind the piston Es of cylinder E' as same is drawn outwards. An outlet
valve is also provided, the escape of air or liquid through which is regulated by
a screw e placed at the top, so as to be perfectly accessible for adjustment.
The spring acting upon the door when same is opened may be arranged in any
suitable manner, the arrangement shown in the drawing consisting in a roller Y
carried by the part A and acting upon an arm or arms Z connected to a spiral
spring contained in the box Z', so as to place such spring in tension or compres-
sion when the door is opened.
The operation of the apparatus is as follows:-When the door C is opened the .
teeth a of the grooved cam or part A, by gearing with the teeth d of the three-
armed lever D, D1, D2, cause the latter to turn on its pivot, so bringing one of
the pins d,, on its two oppositely extending arms D1, D2, opposite the opening to
the groove a¹ of the cam or part A, and at the same time the third arm D of the
lever acts on the piston rod E of the air or liquid cushioning cylinder El so as to
draw the piston E in same forward, air or liquid being allowed to enter the
cylinder behind such piston by means of valve . By the time the forward move-
ment of the piston Es has been completed the pin on one of the two cross arms D¹, D³,
of the lever will have entered the groove a¹ in the cam or part A, so that on the
further opening of the door C, groove a¹ will encircle and travel round such pin
and the lever will thus be prevented from returning to its normal position under
the action of a vacuum which might possibly be formed in the air or liquid
cushioning cylinder E¹ after the teeth a the cam or part A. and those of the
lever D, D, D, have become disengaged, and which would tend to draw the
piston Es back and with it the lever D, D1, D2, to which as above stated it is pivotted.
When the door C under the action of its spring is allowed to close it will turn
freely until the pin or on the arm of the lever has left the groove a¹ in the
cam or part A which it had engaged, when the teeth of such cam or part and
those of the lever D, D1, D2, will immediately engage and the latter acting on
the piston rod E of the air or liquid cushioning cylinder El will through the
pressure of air or liquid on the back of the piston ensure the door closing without
jar or shock, the speed of closing being regulated by screw el which controls the
only outlet for air or liquid drawn in through the inlet valve e³.
Although I have described this invention as applied in connection with a door
opening both ways it will readily be seen that it can be applied to a door open-
ing in one direction only, in which case either the arm D or the arm D³ (and the
pin d or d which they respectively carry) will be abolished.
It will also be understood that any suitable arrangement of door spring may be
used in connection with the apparatus above described. Such apparatus may for
instance be employed with a spring of the construction described in the Specifica-
tion of my prior Patent No. 16068 dated 6th December 1884, or the door spring
described in the Specification of my prior Patent No. 11961 dated 3rd September
1887, but it may also be employed with springs of any other suitable construction.
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:
The combination with a door acted upon by a spring which is placed in tension
or compression by the action of opening the door, of a cam or part mounted on
the door spindle and having teeth engaging corresponding teeth on a pivotted
1

page_text: lever connected to the piston rod of a check cylinder, such cam or part also being
provided with a circular groove with which a pin on the pivotted lever engages
when the door is opened, all substantially as and for the purpose specified.
Dated this 3rd day of June 1898.
ALLISON BROS.,
Agents for the Applicant.