IMPROVEMENTS IN LOCKS OR FASTENINGS FOR RAILWAY CARRIAGE AND OTHER DOORS
Year: 1878

page_text: "
LETTERS PATENT to Frederick Henry Bagge, of 14, Southampton Buildings, in
the County of Middlesex, Engineer, for the Invention of IMPROVEMENTS IN
LOCKS OR FASTENINGS FOR RAILWAY CARRIAGE AND OTHER DOORS." A
communication from abroad by William Wadbrook Paterson, of Brussels, in
the Kingdom of Belgium; Engineer.
Sealed the 23rd August 1878, in pursuance of an Order of the Lord Chancellor, and
1816
PROVISIONAL SPECIFICATION left by the said Frederick Henry Bagge at
the Office of the Commissioners of Patents on the 24th January 1878.
FREDERICK HENRY BAGGE, of 14, Southampton Buildings, in the County of
Middlesex, Engineer. "IMPROVEMENTS IN LOCKS OR FASTENINGS FOR RAILWAY
CARRIAGE AND OTHER DOORS." A communication from abroad by William
Wadbrook Paterson, of Brussels, in the Kingdom of Belgium, Engineer.
This Invention relates to a peculiar construction and arrangement of fastening
for railway carriage and other doors, whereby they may be readily shut and
effectually secured by simply slamming the door.
.
In carrying out this Invention a fastening is employed having a two-fold action,
combining the properties of an ordinary latch and a sliding bolt. To the end of a
rocking arm or lever, whose fulcrum pin forms the spindle of the lock, there is
pivotted a latch which is free to turn vertically, more or less, upon a horizontal
fulcrum pin in the end of the said rocking arm or lever. Against the rear or inner
end of this latch above or below its fulcrum, as the case may be, operates a spring
which tends simultaneously to turn the latch on its fulcrum in the end of the
rocking lever, and also to push it forward longitudinally after the manner of a
bolt.
Two inclines are made on a plate secured to the door cheek, the one acting
vertically on the under side of the latch and the other horizontally against the end
of the same. The latch bolt rides on the former incline, so that when the door is

page_text: slammed the said latch bolt will be raised or depressed, as the case may be, thereby
releasing a notch made therein from a retaining plate on the door, and allowing the
latch to shoot outwards into a recess or chamber in the door cheek when brought
opposite thereto, thus effectually fastening the same by a combined sneck and bolt
action. On reaching the top of this incline the latch drops slightly so as to engage
with a notch or projection behind such incline at the same time that it is being
pushed or shot forward, by which means perfect security is obtained against
the recoil or accidental re-opening of the door in case the latch should fail to be
shot out.
On unlocking the fastening the latch bolt is withdrawn from the recess in the
door cheek till its end is flush with the edge of the door, and when the handle or
key is released and the door pulled open the said latch moves outwards and
downwards, and is thus brought into the position it will assume for permitting of
the slamming the door to, the position of the handle always indicating whether the
door is securely shut or not, as in opening the door the handle must be turned,
thereby withdrawing the latch longitudinally after the manner of a bolt from its
recess in the door cheek, and so releasing the door.
In slamming the door the latch is lifted by the first incline so as to release the
retaining notch, and is at the same time pushed back by the second incline which
acts against the end of it.
In order to prevent the door from-sinking and to diminish the strain upon the
lock or fastening and hinges when the door is shut, the well-known arrangement of
a wedge or incline fitted to the door and engaging with a corresponding incline on
the door cheek may be used in combination with the before-mentioned lock or
fastening.
A stop is fitted to the lock plate to arrest the forward movement of the rocking
lever when the door is locked.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Frederick Henry Bagge in the Great Seal Patent Office on the 23rd
August 1878.
FREDERICK HENRY BAGGE, of 14, Southampton Buildings, in the County of
Middlesex, Engineer. "IMPROVEMENTS IN LOCKS OR FASTENINGS FOR RAILWAY
CARRIAGE AND OTHER DOORS.". A communication from abroad by William
Wadbrook Paterson, of Brussels, in the Kingdom of Belgium, Engineer.
The said Invention relates to a peculiar construction and arrangement of
fastening for railway carriage and other doors, whereby they may be readily shut
and effectually secured by simply slamming the door. In carrying out this
Invention a fastening is employed, having a two-fold action, combining the pro-
perties of an ordinary latch an a sliding bolt.
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the several Figures on the explanatory Sheet of Drawings hereunto annexed, the
same letters of reference indicating corresponding parts in all the Figures.
Figure 1 of the Drawings represents a face view of the lock plate on the door
frame. Figure 2 is an edge view of the same.
Figure 3 is a vertical section of the lock and parts connected therewith taken
along the line 1-2 in Figure 4.
Figure 4 is a.sectional plan of the lock, the section being taken just above the
latch bolt.
Figure 5 is a vertical transverse section taken through the centre line of the lock
spindle.
+
Figure 6 is a face view of the edge of the lock fitted on to the door.
And, Figure 7 represents a slight modification in the notching of the latch bolt.
To the end of the rocking arm or lever A, the fulcrum pin a of which forms the
spindle of the lock, there is pivotted a latch B which is free to turn vertically more
or less upon a horizontal fulcrum pin b in the end of the said rocking arm or lever.
Against the rear or inner end of this latch above or below its fulcrum, as the case
may be, operates a spring C which tends simultaneously to turn the latch B on its
fulcrum b in the end of the rocking lever A, and also to push it forward longi-
tudinally after the manner of a bolt.
Two inclines c and d are made on a plate secured to the door cheek, the one
incline c acting vertically on the under side of the latch B, and the other incline d
acting horizontally against the end of the same. The latch bolt rides on the former
incline c, so that when the door is slammed the said latch bolt will be raised or de-
pressed, as the case may be, thereby releasing a notch e made therein from a retaining
plate fon the door, and allowing the latch to shoot outwards into a recess or chamber g
in the door cheek when brought opposite thereto, thus effectually fastening the
door by a combined sneck and bolt action. On reaching the top of this incline c,'
the latch drops slightly so as to engage with a notch or projection h behind such
incline at the same time that it is being pushed or shot forward, by which means
perfect security is obtained against the recoil or accidental re-opening of the door in
case the latch should fail to be shot out.
On unlocking the fastening the latch bolt is withdrawn from the recess g in the
door cheek till its end is flush with the edge of the door, and when the handle or
key is released and the door pulled open, the said latch moves outwards and down-
wards, and is thus brought into the position it will assume for permitting of the
slamming the door, the position of the handle always indicating whether the door
is securely shut or not, since on opening the door the handle must be turned, thereby
withdrawing the latch longitudinally after the manner of a bolt from its recess in
the door cheek and so releasing the door, whilst in slamming the door the latch is

page_text: lifted by the first incline c so as to release the retaining notch, and is at the same
time pushed back by the second incline d which acts against the end of it.
.
In order to prevent the door from sinking and to diminish the strain upon the
lock or fastening and hinges when the door. is shut, the well-known arrangement of
a wedge or incline fitted to the door and engaging with a corresponding incline on
the door cheek, may be used in combination with the before-mentioned. lock or
fastening. A stop is fitted to the lock plate to arrest the forward movement of
the rocking lever when the door is locked.
Figure 7 represents a portion of the lock showing a slight modification of the
notching of the latch bolt. In this case, in lieu of having a notch with two sides, as
shown in Figure 3, the said latch bolt B may be made with steps e¹, e¹¹, the step e¹
serving the purpose of the two-sided notch e of the previous arrangement, whilst
the step e answers the purpose of the stop i.
Having now described and particularly ascertained the nature of the said In-
vention, and the manner in which the same is or may be used or carried into effect,
I would observe in conclusion that what I consider to be novel and original, and
therefore claim as the Invention secured to me by the herein-before in part recited
Letters Patent is,-
The combination of the lever arm A with its pivot b, the duplex action latch bolt
B with its notch or notches e, the spring C acting above or below the pivot, and the
inclines c and d, when arranged so as to operate together substantially in the
manner and for the purpose herein-before described, and illustrated by the Drawings
hereunto annexed.
In witness whereof, I, the said Frederick Henry Bagge, have hereunto set my
hand and seal, this Twenty-second day of August, in the year of our Lord
One thousand eight hundred and seventy-eight.
FREDERICK HENRY BAGGE. (L.S.)
Witness,
EDWIN P. ALEXANDER,
Consulting Engineer and Patent Agent,
14, Southampton Buildings,
Chancery Lane,
W.C.