Year: 1887

page_text: WILLIAM FRASER Engineer 49 Oxford Road Finsbury Park, London, N. do hereby
declare the nature of this invention to be as follows:-
A cylinder about 5" long & about 1 in diar. with plate marked, B, for attaching
same to door post by means of four screws or otherwise the cylinder A being sunk into
the door post flush with the plate, B, a corresponding plate marked, C, is attached
& sunk flush to the hinged edge of this door. Or the two plates can be made in
the form of an ordinary hinge one half attached to the edge of the door & the
other half attached to the Door post the cylinder being attached to the latter half.
D, is a piston block about 14" or thereby long made to fit cylinder, A, with a small
valve marked, E, in the bottom end of it. F, is a spiral spring of sufficient strength
to close the door. G, is a connecting pin for causing connecting rod, H, to travel.
The other end of same being attached to plate, C, by means of a pin joint marked, J.
There is a slotted hole in plate to allow the connecting rod, H, free access & egress.
J, is a casing of thin brass of sufficient hight to prevent the oil with which the
cylinder is charged with from being lost when at work. K & L, resply. are guides
for the connecting pin. M, is an upright plate or shield to prevent the oil spurting
up when working. N, is a shield also to prevent the oil being sent out at the slotted
hole, O, in plate, B. Cylinder A is slotted on the top side to within about 1" of the
end for pin, G, to travel backwards & forwards in G, is attached to, D, about the
middle & is about long & stands upright. There is a row of small holes bored on
either side of the sides of cylinder A, for the purpose of allowing the oil in the box to
flow back again when forced out. These holes also allows the oil free access from the
cylinder I.E. when the piston block is being drawn out the oil escapes, freely thro'
said holes when at work us seen in Figure I Plate, C, draws H, out when the door is
being opened H, draws block, D, along with it & D, compresses spring, F, the moment

page_text: the door is let go, F, pushes piston, D, back again. D, is not retarded in any way
until the bottom end of it passes the slot marked, P, immediately the block arrives at
that point it compresses the oil in that part of the cylinder that has neither escape
holes nor slot & the oil has to make its escape thro' valve, E, which can be made any
size required. Thus when the door is within a few inches of being closed the oil then
being caught between the end of the cylinder, A, & the piston block. The oil having
to force its way thro' valve E, the door is thus shut as gently as by the hand,
& without noise or slamming the oil will last for years as it is practically sealed up
& cannot get away, the closer complete only weight about 6 oz. or thereby & can be
retailed to the Public about 1/- or thereby each casing, J, is fitted with a loose cover
on the top to allow easy access to the working parts of which may be said really
works in an oil box.

page_text: I, WILLIAM FRASER of 49 Oxford Road, Finsbury Park, London N., 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:-
This invention relates to improvements, in concealed, and other automatic door
closers, and liquid checks, as hereinafter described, and consists in improvements in
the class of door closer and check described by Robert Adams in his Specification
No. 2718 A.D. 1885.
Figure 1 represents a complete vertical section of a concealed automatic door
closer, and liquid check, constructed according to my invention. It will be seen that
the parts of the said combined apparatus, are in the positions which they normally
assume, when a door, to which my invention is applied, is closed.
Figure 2 represents a top side view, and part horizontal section of the said combined
apparatus, and which said view, is taken upon the dotted lines A B figure 1.
Figure 3 is a transverse vertical section, of the said combined apparatus, on the
dotted lines CD figure 1, showing the end barrel part of the enclosing casing, valve,
end of trunk cylinder or piston block, and faceted end of adjusting rod, by means of
which latter, the ingress of oil to the inner chamber or cylinder, is regulated.
Figure 4 represents partly in elevation, and partly in section, my said new or
improved combined door check and spring, with the parts in the positions which they
normally assume, when a door is open.
Figure 5 shows a perspective view upon a similar scale, the said combined apparatus,
applied to a door, which is also shown open.
The same letters of reference, indicate corresponding parts in the several figures
of the drawings.
a is a hinged attachment, consisting of flaps a³, a³, affixedly, and respectively
secured to, the hinged side of a door b, and the adjacent door frame, or upright
stile c, while the said flaps a³, a', are jointed to a', by knuckle connections. Thus, the
flap a', is fixedly secured to the door b, by screws, so likewise is the flap a', fixedly
connected to the door frame or jamb c.
The flap a, has a knuckle snug a*, standing from its front face, and which, on the
door being closed, passes through a slot or gap a, made through the jamb flap a'.
d is a trunk cylinder, or block piston, which is made to reciprocate to and fro,
within the barrel part 9, of an outer enclosing casing 9, (which is fixedly secured to
the back of the flap a³) and upon an inside tube h, running axially within the said
trunk cylinder d, and with its inner end fitting upon a reduced part or neck 17, of a
screw plug i, which fits within a suitably formed hole, made within the flap a³,
is situated below the hole, or gap aº.
which
The trunk cylinder, is jointedly connected to the door flap a³, by a link e, and
connection link or rod f.
The link e is connected to the link f by a bossed eye, on the rear of the latter,

page_text: taking upon a stud or crank e³, on the front top side of the former, while the link e
is connected to the trunk cylinder, by its rear taking upon a neck or reduced part d'
of an arm or upright snug d.
Connection between the link f, and the knuckle snug a³ is made, by a pin f
j is an axially disposed rod, running up the interior of the tube h, and with its
fore part, screwed, upon the end of which, a lock nut j³, takes, for affixing the
said rod, in an adjusted position; and which said screwed part, passes through a plain
hole in the reduced part of the plug i, and has in juxta position to the said screwed
part, a collar and washer 1, of a diameter of the internal bore of the tube h.
The rear of the rod j, is screwed, and faceted, and works within a like screw-
hole, made axially through a shifting plug k, which is kept from rotating, by a
screw or pin, passing either partly, or right through tube h, and working into a
longitudinal slot ³, of the said shifting plug; so that by loosening the lock nut,
and then turning the rod j, by a screw-driver or other means, the shifting plug k, is
made to cover, or uncover more or less, the hole h³, through which, liquid inwardly
passes from the end chamber , disposed between the rear end of the trunk cylinder,
and the end cap g³, of the barrel part of the enclosing casing gª.
h is an inlet valve hole, in the rear of tube 1, and through which, oil passes into
the interior of same, from the rear chamber 1, then passing along, or up the interior of
the shifting plug or valve k, then forcing its way along the passages on the screw j³,
along the interior of said tube h, then ultimately through the holes h³, into the front
chamber again; that is, this displacement of liquid, takes place, when the door is closing.
These holes are so disposed along tube h, that when the door is fully opened, a number
of them at the rear chamber end, are all open, to allow the liquid to escape, then as
the door closes. they are one by one, cut off, (the travelling trunk cylinder passing
over them) until there is only the one hole 2, which is thoroughly under control of
the valve k. Thus, when a door is opened, the rear chamber immediately fills with
liquid through the valve m-The moment the closing action commences, the valve m
closes, then the only means of escape for the liquid is through the holes h³, which are
cut off one by one, as the trunk cylinder returns to its normal position.
By this arrangement, the speed of a door when closing is so gradually arrested,
that no shock or noise is caused whatever.
Disposed between the inner face of the plug i, and the shoulder of the reduced
part, and also surrounding the tube h, is a coiled spring n, which is employed for the
springing back of a door to its closed position, after having been opened.
Thus, the action of the combined apparatus, is as follows.
On the door being opened, the enclosing casing and tube 4, with central rod j, and
their auxiliary parts remain quiescent, while the trunk cylinder d, is drawn forward,
through the intervention of the links e and f; the result is, that the oil settling at the
lower part of the enclosing casing, passes outwardly through the valve m of the said
trunk cylinder d, into the rear compartment 1, and is from thence forced or conveyed
inwardly through the hole h2, up the middle of the shifting plug k, into the interior
of the tube, then outwardly through the holes h³, on the forward reciprocation of
the said trunk cylinder.
The rate of motion at which the door is closed, is dependent upon the rate at which
oil is allowed to flow through the partially covered hole 2, into the interior of the
tube h, from whence it flows back again into the enclosing casing; so that on a door
being opened, the spring is compressed, and the liquid forced at a determinate rate
of motion, into the interior of the tube h, and from thence through holes ³, into the
enclosing casing again, as aforesaid.
The liquid flowing into the rear chamber 1, is prevented from returning, by the
closing of the valve m, immediately a return pressure is exerted by the spring, on the
closing of a door, as represented at figure 4.
Although I have described that the combined apparatus is inserted horizontally
within an upright stile of a door frame, yet the same may with slight modification be
applied to either side of a door or door frame, door post transom, or above or below
the floor.

page_text: I wish it to be understood that although I have described the apparatus as a con-
cealed automatic door closer and liquid check, yet the same may be applied upon the
outside of a door and door frame, by modifying some of the parts, and employing
connecting rods, arms, linked arms, chains, or any other suitable connections, with the
parts already mentioned, or equivalents to the links as aforesaid.
Figure represents in longitudinal vertical section, a liquid check, constructed
according to another form of my invention. Figure 7 represents a transverse vertical
section on the dotted lines E F figure 6.
Figure 8 is an elevation of the trunk piston, and figure 9 is an end view of the
same, while figure 10 is an end elevation of the rear end cap of the cylinder.
It will be understood that the said liquid check, can be applied both inside, or on
the outside of a door, door jamb, or frame, and the accessory parts, such as arms,
attachment brackets, joint connections, and such like, are omitted, as the check can be
used with such accessory parts, as are now in common use.
a is a cylinder, and a, a, are end caps thereof. The end cap a³, has a regulating
screw pin c, passing through the middle of the said cap, and with its inner end adapted
to cover and uncover, the small hole c³, of a series of holes c, made through the top
side, and at the rear end of an axial tube c, carried by the end cap a².
Working within the interior of the cylinder a. and upon the open ended tube c, is a
trunk piston and piston rod b, 63, the latter of which, is hollow and contracted, at 6³, to
the outside diameter of the tube c.
The said hollow rod &, works through a stuffing box a*, in the front end cap, and
has outlet holes 64, wherethrough liquid in the cylinder at the back of the piston, flows
to the front of the piston, while liquid flows from the front of the piston, to the back
thereof, through valves b³, disposed at the rear enclosed ond of the said trunk piston.
The return of the parts to their normal positions, and the closing of a door, is effected
by an interiorly disposed coiled spring n.
The action of the combined check and spring, is as follows-
On a door being opened, the spring is compressed between the trunk piston and
front end cap, and the oil in front of piston, is passed to the back thereof, through the
valves 6, which instantly close, on the closing of a door, produced by the force given
out by the spring. The valves 6, now being closed, the oil contained at the back of
the piston, is forced through the uncovered holes c, c, in the tube c, which then passes
out at its open end, into the hollow of the piston rod, and from thence out of the
holes 6, into the cylinder again, in front of the piston.
The door closes at a somewhat constant velocity, until the contracted part 63, of the
trunk piston, reaches the holes c³, when the door's velocity, becomes immediately
retarded, until the liquid is allowed only to be forced through the hole c*, which is
regulated in its passage, by the inner end of the plug c³, which when rotated, covers
and uncovers more or less, the said hole.
The trunk piston, may if necessary, be substituted by that of a cup leather piston,
with the same arrangement of piston rod, thus dispensing with the valves b*, but with
one of the holes of the inner tube, covered by a yielding or india rubber ring, so as to
admit of liquid being drawn, on the forward stroke, into the back chamber of the
cylinder, thereby counteracting any vacuum which may be incidentally created, within
the back chamber.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I wish it to be under-
stood that I do not claim anything described and claimed by Robert Adams in the
before mentioned Specification No. 2718 A.D. 1885, but I declare that what I
claim is :-
First Combining with a concealed door spring or check, or a door spring and check
combined, of hinged or knuckle flaps a, a, jointed as described and represented;
which are fixedly secured to a door and door frame, and with a knuckle snug a* of the
one part, passing through a gap of the other part.
Secondly-The combination with a door check and spring, as herein described, of a

page_text: trunk cylinder d, with upright arm d, d³, and jointedly connected to a hinge attach-
ment plate a, a², by links e, f, or chains or connecting rods or arms, which are
constructed and arranged as set forth; whereby the opening of a door, compresses the
spring, and passes the liquid within the apparatus from one part to the other, for
limiting the door's acceleration when closing, as described and illustrated in figures 1
to 6.
Thirdly-The combination with a door closer, and liquid check, of an interiorly
disposed tube h, with inlet and outlet holes h2, h3, as set forth in figures 1 to 6.
Fourthly -The combination with the inlet hole h³, of the tube h, of the shifting
plug k, whereby the closing of the door is regulated, as set forth in figures 1 to 5.
Fifthly The means herein described, for adjusting, traversing and affixing in
position, the shifting plug k, as set forth in figures 1 to 5.
Sixthly: The improvements in a combined door spring, and liquid check, as
herein described and illustrated; and which said combined spring and check, is con-
structed, arranged and operates, substantially as set forth in figures 1 to 5.
Seventhly-A combined liquid check and spring, consisting of a cylinder or barrel,
with an axially directed open ended inner tube, with holes or passages, made through
it; and working within the said cylinder, and upon the axially directed tube, is a
trunk piston (or cup leather piston) and hollow piston rod, the former having valve
and valve outlets, while the latter has hole outlets, with a contracted rear part, of the
outside diameter of the tube, upon which it works, and one of which said holes, in the
axially directed tube, is increased or decreased in size, by the inner end of a regulating
screw pin, working within the rear end cap, and which said parts are constructed,
and arranged, and operate, substantially as described and set forth in figures 6, 7, 8, 9
and 10.
Lastly-The combination of the regulating screw pin c³, with the hole c³, of the
centrally disposed tube c, as set forth in figures 6, 7, 8, 9 and 10.
Dated this Seventh day of June 1888.
WILLIAM FRASER.
By Henry Skerrett,
Agent for Applicant.

page_text: Date of Application, 10th Sept., 1887
Complete Left, 11th June, 1888
Complete Accepted, 13th July, 1888
WILLIAM FRASER Engineer 49 Oxford Road Finsbury Park, London, N. do hereby
declare the nature of this invention to be as follows:-
A cylinder about 5" long & about 1" in diar. with plate marked, B, for attaching
samo to door post by means of four screws or otherwise the cylinder A being sunk into
the door post flush with the plate, B, a corresponding plate marked, C, is attached
& sunk flush to the hinged edge of this door. Or the two plates can be made in
the form of an ordinary hinge one half attached to the edge of the door & the
other half attached to the Door post the cylinder being attached to the latter half.
D, is a piston block about 11" or thereby long made to fit cylinder, A, with a small
valve marked, E, in the bottom end of it. F, is a spiral spring of sufficient strength
to close the door. G, is a connecting pin for causing connecting rod, H, to travel.
The other end of same being attached to plate, C, by means of a pin joint marked, J.
There is a slotted hole in plate to allow the connecting rod, H, free access & egress.
J, is a casing of thin brass of sufficient hight to prevent the oil with which the
cylinder is charged with from being lost when at work. K & L, resply. are guides
for the connecting pin. M, is an upright plate or shield to prevent the oil spurting
up when working. N, is a shield also to prevent the oil being sent out at the slotted
hole, O, in plate, B. Cylinder A is slotted on the top side to within about 1" of the
end for pin, G, to travel backwards & forwards in G, is attached to, D, about the
middle & is about 3" long & stands upright. There is a row of small holes bored on
either side of the sides of cylinder A, for the purpose of allowing the oil in the box to
flow back again when forced out. These holes also allows the oil free access from the
cylinder I.E. when the piston block is being drawn out the oil escapes, freely thro'
said holes when at work as seen in Figure I Plate, C, draws H, out when the door is
being opened H, draws block, D, along with it & D, compresses spring, F, the moment

page_text: the door is let go, F, pushes piston, D, back again. D, is not retarded in any way
untill the bottom end of it passes the slot marked, P, immediately the block arrives at
that point it compresses the oil in that part of the cylinder that has neither escape
holes nor slot & the oil has to make its escape thro' valve, E, which can be made any
size required. Thus when the door is within a few inches of being closed the oil then
being caught between the end of the cylinder, A, & the piston block. The oil having.
to force its way thro' valve E, the door is thus shut as gently as by the hand,
& without noise or slamming the oil will last for years as it is practically sealed up
& cannot get away, the closer complete only weight about 6 oz. or thereby & can be
retailed to the Public about 1/- or thereby each casing, J, is fitted with a loose cover
on the top to allow easy access to the working parts of which may be said really
works in an oil box.

page_text: [, WILLIAM FRASER of 49 Oxford Road, Finsbury Park, London N., 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:
This invention relates to improvements, in concealed, and other automatic door
closers, and liquid checks, as hereinafter described.
Figure 1 represents a complete vertical section of a concealed automatic door
closer, and liquid check, constructed according to my invention. It will be seen that
the parts of the said combined apparatus, are in the positions which they normally
assume, when a door, to which my invention is applied, is closed.
Figure 2 represents a top side view, and part horizontal section of the said combined
apparatus, and which said view, is taken upon the dotted lines A B figure 1.
Figure 3 is a transverse vertical section, of the said combined apparatus, on the
dotted lines CD figure 1, showing the end barrel part of the enclosing casing, valve,
end of trunk cylinder or piston block, and faceted end of adjusting rod, by means of
which latter, the ingress of oil to the inner chamber or cylinder, is regulated.
Figure 4 represents partly in elevation, and partly in section, my said new or
improved combined door check and spring, with the parts in the positions which they
normally assume, when a door is open.
Figure 5 shows a perspective view upon a smaller scale, the said combined apparatus,
applied to a door, which is also shown open.
The same letters of reference, indicate corresponding parts in the several figures
of the drawings.
a is a hinged attachment, consisting of flaps a², a³, affixedly, and respectively
secured to, the hinged side of a door b, and the adjacent door frame, or upright
stile C₁ while the said flaps a², a³, are jointed at a*, by knuckle connections. Thus, the
flap a, is fixedly secured to the door b, by screws, so likewise is the flap a³, fixedly
connected to the door frame or jamb c.
The flap a, has a knuckle snug a°, standing from its front face, and which, on the
door being closed, passes through a slot or gap a, made through the jamb flap a³.
d is a trunk cylinder, or block piston, which is made to reciprocate to and fro,
within the barrel part 92, of an outer enclosing casing g, (which is fixedly secured to
the back of the flap a) and upon an inside tube h, runuing axially within the said
trunk cylinder d, and with its inner end fitting upon a reduced part or neck, of a
screw plug i, which fits within a suitably formed hole, made within the flap a', which
is situated below the hole, or gap a³.
The trunk cylinder, is jointedly connected to the door flap a², by a link
connection link or rod f.
and
The link e is connected to the link f, by a bossed eye, on the rear of the latter,

page_text: taking upon a stud or crank e², on the front top side of the former, while the link e,
is connected to the trunk cylinder, by its rear taking upon a neck or reduced part d³,
of an arm or upright snug .
Connection between the link f, and the knuckle snug a' is made, by a pin f³.
jis an axially disposed rod, running up the interior of the tube h, and with its
fore part, screwed, upon the end of which, a lock nut 13, takes, for affixing the
said rod, in an adjusted position; and which said screwed part, passes through a plain
hole in the reduced part of the plug i, and has in juxta position to the said screwed
part, a collar and washer *, of a diameter of the internal bore of the tube .
The rear of the rod j, is screwed, and faceted, and works within a like screw-
hole k³, made axially through a shifting plug k, which is kept from rotating, by a
screw or pin, passing either partly, or right through tube h, and working into a
longitudinal slot k³, of the said shifting plug; so that by loosening the lock nut j³,
and then turning the rod j, by a screw-driver or other means, the shifting plug k, is
made to cover, or uncover more or less, the hole h³, through which, liquid inwardly
passes from the end chamber 1, disposed between the rear end of the trunk cylinder,
and the end cap 9, of the barrel part of the enclosing casing g³.
h2 is an inlet valve hole, in the rear of tube h, and through which, oil passes into
the interior of same, from the rear chamber 1, then passing along, or up the interior of
the shifting plug or valve k, then forcing its way along the passages on the screw j³,
along the interior of said tube h, then ultimately through the holes ³, into the front
chamber again;
that is, this displacement of liquid, takes place, when the door is closing.
These holes are so disposed along tube h, that when the door is fully opened, a number
of them at the rear chamber end, are all open, to allow the liquid to escape, then as
the door closes, they are one by one, cut off, (the travelling trunk cylinder passing
over them) until there is only the one hole h², which is thoroughly under control of
the valve k. Thus, when a door is opened, the rear chamber immediately fills with
liquid through the valve m-The moment the closing action commences, the valve m
closes, then the only means of escape for the liquid is through the holes ³, which are
cut off one by one, as the trunk cylinder returns to its normal position.
By this arrangement, the speed of a door when closing is so gradually arrested,
that no shock or noise is caused whatever.
Disposed between the inner face of the plug i, and the shoulder of the reduced
part, and also surrounding the tube h, is a coiled spring n, which is employed for the
bringing back of a door to its closed position, after having been opened.
Thus, the action of the combined apparatus, is as follows.
On the door being opened, the enclosing casing and tube h, with central rod j, and
their auxiliary parts remain quiescent, while the trunk cylinder d, drawn forward,
through the intervention of the links e and f; the result is, that the oil settling at the
lower part of the enclosing casing, passes outwardly through the valve m of the said
trunk cylinder d, into the rear compartment 1, and is from thence forced or conveyed
inwardly through the hole h³, up the middle of the shifting plug k, into the interior
of the tube h, then outwardly through the holes ³, on the forward reciprocation of
the said trunk cylinder.
The rate of motion at which the door is closed, is dependent upon the rate at which
oil is allowed to flow through the partially covered hole ², into the interior of the
tube h, from whence it flows back again into the enclosing casing; so that on a door
being opened, the spring is compressed, and the liquid forced at a determinate rate
of motion, into the interior of the tube h, and from thence through holes /³, into the
enclosing casing again, as aforesaid.
The liquid flowing into the rear chamber 1, is prevented from returning, by the
closing of the valve m, immediately a return pressure is exerted by the spring, on the
closing of a door, as represented at figure 4.
Although I have described that the combined apparatus is inserted horizontally
within an upright stile of a door frame, yet the same may with slight modification be
applied to either side of a door or door frame, door post transom, or above or below
the floor.

page_text: I wish it to be understood that although I have described the apparatus as a con-
cealed automatic door closer and liquid check, yet the same may be applied upon the
outside of a door and door frame, by modifying some of the parts, and employing
connecting rods, arms, linked arms, chains, or any other suitable connections, with the
parts already mentioned, or equivalents to the links as aforesaid.
Figure 6 represents in longitudinal vertical section, a liquid check, constructed
according to another form of my invention. Figure 7 represents a transverse vertical
section on the dotted lines E F figure 6.
Figure 8 is an elevation of the trunk piston, and figure 9 is an end view of the
same, while figure 10 is an end elevation of the rear end cap of the cylinder.
It will be understood that the said liquid check, can be applied both inside, or on
the outside of a door, door jamb, or frame, and the accessory parts, such as arms,
attachment brackets, joint connections, and such like, are omitted, as the check can be
used with such accessory parts, as are now in common use.
a is a cylinder, and a², a³, are end caps thereof. The end cap a, has a regulating
screw pin c, passing through the middle of the said cap, and with its inner end adapted
to cover and uncover, the small hole c³, of a series of holes c', made through the top
side, and at the rear end of an axial tube c, carried by the end cap a³.
Working within the interior of the cylinder a, and the open ended tube
upon
C, is 8
trunk piston and piston rod b, 62, the latter of which, is hollow and contracted, at 6³, to
the outside diameter of the tubo c.
The said hollow rod 2, works through a stuffing box at, in the front end cap, and
has outlet holes 64, wherethrough liquid in the cylinder at the back of the piston, flows
to the front of the piston, while liquid flows from the front of the piston, to the back
thereof, through valves 65, disposed at the rear enclosed end of the said trunk piston.
The return of the parts to their normal positions, and the closing of a door, is effected
by an interiorly disposed coiled spring n.
The action of the combined check and spring, is as follows-
On a door being opened, the spring is compressed between the trunk piston and
front end cap, and the oil in front of piston, is passed to the back thereof, through the
valves, which instantly close, on the closing of a door, produced by the force given
out by the spring. The valves 6, now being closed, the oil contained at the back of
the piston, is forced through the uncovered holes c³, c, in the tube c, which then passes
out at its open end, into the hollow of the piston rod, and from thence out of the
holes 6, into the cylinder again, in front of the piston.
The door closes at a somewhat constant velocity, until the contracted part 63, of the
trunk piston, reaches the holes c, when the door's velocity, becomes immediately
retarded, until the liquid is allowed only to be forced through the hole c', which is
regulated in its passage, by the inner end of the plug c², which when rotated, covers
and uncovers more or less, the said hole.
The trunk piston, may if necessary, be substituted by that of a cup leather piston,
with the same arrangement of piston rod, thus dispensing with the valves 6º, but with
one of the holes of the inner tube, covered by a yielding or india rubber ring, so as to
admit of liquid being drawn, on the forward stroke, into the back chamber of the
cylinder, thereby counteracting any vacuum which may be incidentally created, within
the back chamber.
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 :-
First Combining with a concealed door spring or check, or a door spring and check
combined, of hinged or knuckle flaps a, a, jointed as described and represented;
which are fixedly secured to a door and door frame, and with a knuckle snug a³ of the
one part, passing through a gap of the other part.
Secondly-Working within the interior of the barrel, of a combined spring and
check, of a trunk cylinder or piston with one end thereof, working and sliding upon a
concentric and internally disposed tube, as described and set forth,

page_text: Thirdly--The combination with a door check and spring, as herein described, of a
trunk cylinder d, with upright arm d, d, and jointedly connected to a hinge attach-
ment plate a, a, by links e, f, or chains or connecting rods or arms, which are
constructed and arranged as set forth; whereby the opening of a door, compresses the
spring, and passes the liquid within the apparatus from one part to the other, for
limiting the door's acceleration when closing, as described and illustrated in figures 1.
to 6.
:-
Fourthly The combination with a door closer, and liquid check, of an interiorly
disposed tube h, with inlet and outlet holes h³, h³, as set forth in figures 1 to 6.
Fifthly The combination with the inlet hole 2, of the tube h, of the shifting
plug k, whereby the closing of the door is regulated, as set forth in figures 1 to 5.
Sixthly-The means herein described, for adjusting, traversing and affixing in
position, the shifting plug k, as set forth in figures 1 to 5.
Seventhly The improvements in a combined door spring, and liquid check, as
herein described and illustrated; and which said combined spring and check, is con-
structed, arranged and operates, substantially as set forth in figures 1 to 5.
Eighthly A combined liquid check and spring, consisting of a cylinder or barrel,
with an
axially directed open ended inner tube, with holes or passages, made through
it; and working within the said cylinder, and upon the axially directed tube, is a
trunk piston (or cup leather piston) and hollow piston rod, the former having valve
and valve outlets, while the latter has hole outlets, with a contracted rear part, of the
outside diameter of the tube, upon which it works, and one of which said holes, in the
axially directed tube, is increased or decreased in size, by the inner end of a regulating
screw pin, working within the rear end cap, and which said parts are constructed,
and arranged, and operate, substantially as described and set forth in figures 6, 7, 8, 9
and 10.
Lastly-The combination of the regulating screw pin c³, with the hole c³, of the
centrally disposed tube c, as set forth in figures 6, 7, 8, 9 and 10.
Dated this Seventh day of June 1888.
WILLIAM FRASER.
By Henry Skerrett,
Agent for Applicant.