IMPROVEMENTS IN DOOR CHAINS OR DOOR FASTENINGS
Year: 1877

page_text: LETTERS PATENT to William Henry Tonks, of the Firm of William Tonks and
Sons, of Birmingham, in the County of Warwick, Manufacturers, for the
Invention of "IMPROVEMENTS IN DOOR CHAINS OR DOOR FASTENINGS."
Sealed the 1st February 1878, and dated the 12th September 1877.
PROVISIONAL SPECIFICATION left by the said William Henry Tonks at
the Office of the Commissioners of Patents on the 12th September 1877.
WILLIAM HENRY TONKS, of the Firm of Willian Tonks and Sons, of Birmingham,
in the County of Warwick, Manufacturers. "IMPROVEMENTS IN DOOR CHAINS OR
DOOR FASTENINGS."
My Invention relates to those kinds of door fastenings commonly called door
chains, and my said Invention consists, firstly, in combining with the slotted plate
of the door chain or door fastening a sliding bolt, so that the door to which the
chain is applied may whon required be fastened by the use of the said bolt. I apply
the said sliding bolt to that end of the slotted plate which is situated near the edge
of the door, the said bolt working in a box or between guides on the inner face of
the slotted plate. The sliding bolt is worked by a head or thumb plate external to
the slotted plate, the stem of the said thumb plate moving in a slot in the slotted
plate. Instead of attaching the end of the door chain to the door fraine by means
of an eye plate as usual, I use in place thereof a staple plate having an eye made
upon it, to which eye the chain is permanently connected. Into this staple plate the
sliding bolt takes when the latter is shot and thereby fastens the door to which the
door chain is applied.
By combining a sliding bolt with the door chain plate according to this part of
my Invention a separate inside bolt or other inside fastening may be dispensed with,
and the closed door may be fastened from the inside of the room by means
of the said sliding bolt, or the door be prevented from being opened beyond a
limited extent by the use of the door chain at the option of the person in the

page_text: My Invention consists further of the following improvements in door chains or
door fastenings, the said improvements having for their object to enable the person
in the room to disengage the door chain from its slotted plate at a distance from the
door, as for example, from a bed.
Instead of making at the end of the longitudinal slot in the slotted plate an
enlargement as usual, through which the head or stud on the free end of the chain
is passed to engage it with the said slotted plate, I make at the said end of the slot
a second or cross slot, the said cross slot extending from the upper edge of the
longitudinal slot to the bottom of the slotted plate, the bottom of the cross slot being
open. This cross slot is sufficiently large to permit of the passage through it of the
stud on the free end of the door chain. To the eye of the end or stud of the chain
a cord or wire is fastened, which cord or wire passes to the bed within reach of the
hand, or to any other part of the room. When it is wished to unfasten the door
chain for opening the door, the cord or wire described is pulled so as to withdraw
the head or stud of the chain from the top or inner end of the longitudinal slot in
the slotted plate to the cross and wider slot at the opposite end thereof. On
the head or stud reaching the said cross slot it falls through it and the door is
unfastened.
Or instead of the cross wide slot described in the slotted plate a slot of the
ordinary kind may be employed, that part of the said plate forming the lower edge
of the slot, being made of a separate jointed piece, so jointed to the other part as to
move in a vertical plane when released, and open the said slot, and permit the head or
stud of the door chain to fall from the slotted plate. The said jointed piece or part
of the slotted plate is maintained in its raised or normal position by a small snap or
other bolt or catch taking into the end of the jointed piece opposite that end which
is jointed to the slotted plate. The end of this bolt or catch is provided with an
eye to which the releasing cord or wire is fastened. By pulling the said bolt or catch
by the said cord or wire the jointed piece of the slotted plate is released, and falls by
its own weight, thereby opening the bottom of the slot in the slotted plate, and
permitting the rod or stud of the chain to escape therefrom and unfasten the door.
Door chains constructed according to my Invention are particularly useful for
bedroom doors, but may be applied to other doors.
The sliding bolts, herein first described, may either be used in conjunction with
ordinary slotted chain plates, or with the arrangements of slotted chain plates
described, whoreby the door chains may be unfastened at a distance from the doors.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Henry Tonks in the Great Seal Patent Office on the 21st
February 1878.
WILLIAM HENRY TONKS, of the Firin of William Tonks and Sons, of Birmingham,
in the County of Warwick, Manufacturers. IMPROVEMENTS IN DOOR CHAINS OR
DOOR FASTENINGS."
"
My Invention relates to those kinds of door fastenings commonly called door
chains, and my said Invention consists, first, in combining with the slotted plate of
the door chain or door fastening a sliding bolt, so that the door to which the chain
is applied may when required be fastened by the use of the said bolt. I apply the
said sliding bolt to that end of the slotted plate which is situated near the edge of
the door; the said bolt working in a box or between guides on the inner face of the
slotted plate. The sliding bolt is worked by a head or thumb plate, external to the
slotted plate; the stem of the said thumb plate moving in a slot in the slotted plate.
Instead of attaching the end of the door chain to the door frame by means of an eye
plate as usual, I use in place thereof a staple plate having an eye made upon it, to
which eye the chain is permanently connected. Into this staple plate the sliding bolt
takes when the latter is shot, and thereby fastens the door to which the door chain
is applied.
By combining a sliding bolt with the door chain plate, according to this part of
my Invention, a separate inside bolt or other inside fastening may be dispensed
with, and the closed door may be fastened from the inside of the room by means
of the said sliding bolt, or the door be prevented from being opened beyond a
limited extent by the use of the door chain at the option of the person in the
room.
My. Invention consists further of the following improvements in door chains or
door fastenings, the said improvements having for their object to enable the
person in the room to disengage the door chain from its slotted plate at a distance
from the door, as for example, from a bed.
Instead of making at the end of the longitudinal slot in the slotted plate an
enlargement as usual, through which the head or stud on the free end of the chain is
passed to engage it with the slotted plate, I make at the said end of the slot a second
or cross slot, the said cross slot extending from the upper edge of the longitudinal
slot to the bottom of the slotted plate, the bottom of the cross slot being open. This
cross slot is sufficiently large to permit of the passage through it of the stud on the
free end of the door chain. To the eye of the head or stud of the chain a cord or
wire is fastened, which cord or wire passes to the bed within reach of the hand, or
to any other part of the room. When it is wished to unfasten the door chain for
opening the door, the cord or wire described is pulled so as to withdraw the head or
stud of the chain from the top or inner end of the longitudinal slot in the slotted
plate to the cross and wider slot at the opposite end thereof. On the head or stud
reaching the said cross slot it falls through it and the door is unfastened.
Or instead of the cross wide slot described in the slotted plate a slot of the
ordinary kind may be employed, that part of the said plate forming the lower edge
of the slot being made of a separate jointed piece, so jointed to the other part as to
move in a vertical plane when released, and open the said slot, and permit the head
or stud of the door chain to fall from the slotted plate. The said jointed piece or
part of the slotted plate is maintained in its raised or normal position by a small
snap or other bolt or catch taking into the end of the jointed piece opposite that
end which is jointed to the slotted plate. The end of this bolt or catch is provided
with an eye to which the releasing cord or wire is fastened. By pulling the said
bolt or catch by the said cord or wire the jointed piece of the slotted plato is released
and falls by its own weight, thereby opening the bottom of the slot in the slotted
plate and permitting the head or stud of the chain to escape therefrom and unfasten
the door,

page_text: Door chains constructed according to my Invention are particularly useful for bed
room doors, but may be applied to other doors.
The sliding bolts, herein first described, may either be used in conjunction with
ordinary slotted chain plates or with the arrangements of slotted chain plates
described, whereby the door chains may be unfastened at a distance from the doors.
I will now proceed to describe, with reference to the accompanying Drawings, the
manner in which my Invention may be performed.
Figure 1 represents a front elevation; and Figures 2 and 3, longitudinal sections
of a door chain or a door fastening provided with a sliding bolt according to my
Invention. In Figures 1 and 2, the sliding bolt is represented in its shot position, and
in Figure 3 in its withdrawn position.
Figure 4 represents an end elevation of the staple and eye plate detached.
Figure 5 is a cross section of the slotted plate taken on the line a, a, Figure 1;
and Figure 6 is a cross section of the said plate taken on the line b, b. Figure 1.
The same letters of reference indicate the same parts in the several Figures of the
Drawings.
e is the plate of the fastening which is fixed to the door; f is the slot in the plate
in which the stud or head of the door chain works in the ordinary way. The
chain g is connected to an eye on the staple plate h. To that end of the plate e,
situated near the edge of the door, a sliding bolt is appliod, the said bolt working in
a box or case on the inner face of the slotted plate e. By means of a head or thumb
plate 2 external to the plate e working in the slot the sliding bolt i may be shot
into or withdrawn from the staple of the combined staple and eye plate h, h².
When the sliding bolt i is shot into its staple h, as illustrated in Figures 1 and 2, the
door to which the door chain or door fastoning is applied is fastened, and when the
sliding bolt is withdrawn, as illustrated in Figure 3, the door may be opened to the
extent permitted by the chain g, as is well understood.
By using with a door a door chain or door fastening of the kind represented in
Figures 1, 2, and 3, a separate inside bolt or other inside door fastening may be
dispensed with, and the closed door may be fastened by means of the sliding bolt i,
or the door may be prevented from being opened beyond a limited extent by the use of
the chain g. In order to prevent the withdrawal of the stud or head g² of the chain g
from the slot f in the plate e excepting by the person in the room, I close or nearly
close the enlarged end of the said slot f through which the stud or head g² may
be drawn to liberate the chain by means of the disck carried on the end of the
spring arm ². By means of the pusher on the spring arm ² the closing disc k
may be pressed inwards so as to open the enlarged end of the slot f, and
permit of the withdrawal of the stud or head g³, and the liberation of the chain g
from the slotted plate e.
In order to introduce the head of the chain g into the slot f, the spring closing
disc is pushed inwards by the said head y², as illustrated in Figure 3, and the latter
may now be passed into the slot f. When the pressure is removed from the disc k
it resumes its normal position and closes the enlarged end of the slot f, and the
head g² of the chain cannot be withdrawn so long as the closing disc occupies that
position.
Figure 7 represents in front elevation, and Figure 8 in cross section, a door chain or
door fastening, constructed according to my Invention, in which the door chain may be
disconnected from its slotted plate at a distance from the door to which the said
door chain is applied. In this arrangement I make at the end of the longitudinal
slotf a cross or vertical slot, the said vertical slot being sufficiently large to permit
of the passage through it of the head or stud on the free end of the chain y.
This second or vertical slot passes from the enlarged end of the ordinary slot f
to the bottom of the slotted plate e, the bottom of the vertical slot f being open. To
the eye of the head or stud a cord or wire m is fastened. This cord or wire m may
be passed to the bed within reach of the hand, or to any other part of the room from
which it may be desired to unfasten the door.
For unfastening the door chain g for opening the doer from a distance from the

page_text: said door, the cord or wire m is pulled so as to slide the stud or head g' from the
position represented in Figure 7 to the enlarged end f* of the slot under which the
vertical slot f is situated. On the head or stud g² reaching the enlarged end f³ it
falls through the vertical slot f, as illustrated in Figure 8, and the chain g is liberated
from the slotted plate, and the door is unfastened.
Figures 9 and 10 represent front elevations, and Figure 11 a back elevation of a
door chain or door fastening constructed according to another of the arrangements of
my Invention. In Figure 9 the door chain is represented connected with the slotted
plate, and in Figure 10 disconnected from the said slotted plate by the opening of
the hinged part of the said plate. In this arrangement a separate piece is jointed
at e to the slotted plate e, the upper edge of the said jointed piece e", when it is
raised into a horizontal position and fixed, forming the lower edge of the slot f in
the slotted plate e, as represented in Figures 9 and 11. When the jointed piece e³
is released it takes the position represented in Figure 10 by its own weight; the slot
fis thereby opened, and the head or stud 2 of the door chain g falls from the said
slotted plate. The jointed piece es is fastened in its normal or raised position, Figures
9 and 11, by the small spring or snap bolt or catch p, engaging under a shoulder s
on the unjointed end of the said piece e', as best seen in Figure 11. The inner end
of the spring bolt or catch p is bevelled, and its outer end is provided with an eye
to which a releasing cord or wire q is fastened, the said releasing cord or wire
being conducted to the bed or other place in the room from which it is wished to
unfasten the door chain.
To release the door chain g the cord or wire q is pulled. The bevelled end of the
spring bolt or catch p is thereby withdrawn from under the shoulder & of the
jointed picce e³, and the latter falls by its own weight into the position represented
in Figure 10. The head or stud g² of the chain g is thereby permitted to escape
from the slotted plate e and the door is unfastened.
P
In Figure 10 the door chain g is represented in the act of falling, after the jointed
part 3 has been released by the withdrawal of the spring bolt or catch p. On
raising the jointed part e into a horizontal position, the spring bolt or catch is
first pushed back by the inclined end of the said jointed partes, and when the latter
has been fully raised into its place the said bolt snaps under the shoulder s, and the
slotted piece e is fastened, and is again ready to receive the head or stud g³ of the
door chain g.
When the parts of the door fastening are in the positions represented in Figures
9 and 11, the said door fastening is used like an ordinary door chain or fastening,
the spring bolt p and its releasing cord or wire q only being used when it is wished
to unfasten the chain at a distance from the door.
I have shown in combination with this part of my Invention a sliding bolt i,
which can be made to take into the staple plate and fasten the door when required,
as herein-before described.
I have also shown in this arrangement a spring closing disc k, k², for closing the
enlarged end of the slot in the slotted plate, and thereby preventing the withdrawal
of the head or stud of the chain from the said slotted plate, excepting when the
closing disc is pushed back or inwards by a person in the room; but I wish
it to be understood that the arrangement of parts for releasing the door chain
ot a distance from the door may be used without the sliding bolt i and the spring
closing disc, 12.
In place of the sliding bolt i, represented in the Drawings, a spring sliding bolt or
latch inay be used, the said spring bolt or latch being withdrawn from the staple by
means of an ordinary spindle and knobs.
Having now described the nature of my Invention and the manner in which the
same is to be perforined, I wish it to be understood that 1 clain as iny Invention of
improvements in door chains or door fastenings,
First. The combination with the slotted plate of the door chain or door fastening
of a sliding bolt, and providing the eye plate to which the chain is connected with
a staple, into or from which the sliding bolt may be shot or withdrawn, so that the

page_text: door to which the chain is applied may when required be fastened by the use of the
said bolt, substantially as herein-before described, and illustrated in Figures 1,2,3,4,5,
6, 9, 10, and 11, of the accompanying Drawings; also the combination with the
slotted plate of the door chain or door fastening of a spring sliding bolt or latch for
fastening or latching the door independently of the door chain, as before described.
Secondly. The improvements in door chains or door fastenings, herein-before
described, and illustrated in Figures 7, 8, 9, 10, and 11, of the accompanying Drawings,
whereby the person in the room can disengage the door chain from its slotted plate
and unfasten the door at a distance from the said door, that is to say, making at
the enlarged end of the longitudinal slot in the slotted plate a vertical or cross slot,
marked in Figures 7 and 8, through which vertical slot the head or door chain
may fall and release the chain, when the said head or stud is brought opposite the
said vertical slot in the manner described; also forming the lower edge of the
longitudinal slot in the slotted plate of a separate jointed piece fastened in its place
by a spring or snap bolt or catch, the withdrawal of the said spring or snap bolt or
catch by the pulling of a cord or wire releasing the said jointed piece, which falls
by its own weight, and thereby permits the head or stud of the door chain to
escape from the slotted plate and unfasten the door, substantially as described, and
illustrated in Figures 9, 10, and 11.
Lastly. The adaptation to the enlarged ends of the slots in the slotted plates of
door chains or door fastenings of a spring closing disc, for the purpose and substantially
as herein-before described, and illustrated in the accompanying Drawings.
In witness whereof, I, the said William Henry Tonks, have hereunto set
my hand and seal, this Eighteenth day of February, in the year of our
Lord One thousand eight hundred and seventy-eight.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
Birmingham.
WILLIAM HENRY TONKS. (L.S.)