IMPROVEMENTS IN MACHINERY OR APPARATUS FOR LOCKING OR CONTROLLING THE HAND LEVERS OF RAILWAY POINTS AND SIGNALS
Year: 1870

page_text: LETTERS PATENT to William Buck, of Upper Tooting, in the County
of Surrey, Engineer, for the Invention of “IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR LOCKING OR CONTROLLING THE HAND LEVERS
OF RAILWAY POINTS AND SIGNALS."
Sealed the 17th February 1871, and dated the 29th November 1870.
5
PROVISIONAL SPECIFICATION left by the said William Buck at the
Office of the Commissioners of Patents, with his Petition, on the
29th November 1870.
I, WILLIAM BUOx, of Upper Tooting, in the County of Surrey,
Engineer, do hereby declare the nature of the said Invention for "Ix-
PROVEMENTS IN MACHINERY OR APPARATUS FOR LOCKING OR CONTROLLING THE
HAND LEVERS OF RAILWAY POINTS AND SIGNALS," to be as follows:-
This Invention relates to certain peculiar arrangements and con-
structions of apparatus for locking or controlling the levers or handles
employed for working railway points and signals in such a manner that
only those signals can be given which correspond to the position of their

page_text: respective points, and that those point levers will be locked by the
movement of their corresponding signal levers; also that it shall be
impossible to give improper or conflicting signals from one and the same
set of levers, thereby relieving the signalman of much responsibility and
ensuring the greater safety of the traffic upon railways especially where 5
a large number of signals and points are worked from one spot.
The first part of my Invention consists in the use of "lever bars" or
bars working direct from the hand levers either vertically or horizontally
provided with longitudinal projections acting upon triggers or cranks
for giving motion to a series or tier of parallel sliding bars, or the 1
motion may be communicated direct without the use of triggers or
cranks, but in either case these bars are to be provided with notches or
stops for receiving the locks attached to the sliding bars above referred
to. By this arrangement the "lever bars are caused to perform a
double function inasmuch as they not only serve to actuate the locks 1
but receive and are locked by the said looks.
3
"
The second part of my Invention relates to the mode of giving motion
to the sliding bars herein-before referred to. This is effected by means
of the aforesaid triggers or cranks which work upon fixed centres and
transmit the motion of the "lever bars", rapidly or suddenly at one or
both ends of the stroke of the hand lever, but are inoperative or at rest
during the remainder of the stroke.. These triggers move the sliding
bars forward in one direction only, the backward motion being effected
by springs or weights.
The third part of my Invention is applicable when inclines or wedges
are placed on the sides or edges of "lever bars" for the purpose of
imparting motion directly or without the intervention of triggers or
cranks in one or both directions to the sliding bars, and consists of loose
clips or shoes which are fitted on to the sliding bars and are capable of
adjusting themselves to the various angles of the inclines or wedges on
the "lever bars."
The fourth part of my Invention consists of frames placed on each
side of the sliding bars, such frames being grooved or recessed either for
the reception of the locks attached to the sliding bars or for auxiliary
locks working between and independently of the said bars.
.
The fifth part of my Invention is applicable when two or more levers
operate upon the same sliding bar, and consists of an auxiliary sliding
plate or lock working between and independently of the sliding bars for

page_text: the
purpose of preventing more than one of these levers being pulled.
over at the same time. The "lever-bárs" are provided with notches or
projections which either give motion to the lock when it is free or
form stops for the."lever bars".against the lock when it is fixed by
another lever.
"
•
The sixth part of my Invention relates to a method of applying
additional or extra locks to the sliding bars after the apparatus is fixed
or at work without displacing the other locking. It consists in the use
of plates. somewhat similar in form to the other locks, which plates are
introduced between the sliding bars and are caused to butt at each end
against the locks already fixed to the sliding bars; or these additional
plates may be secured to the sliding bars by means of studs, bolts, or
clips.
•
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Buck in the Great Seal Patent Office on
the 22nd May 1871.
.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
Buck, of Upper Tooting, in the County of Surrey, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of November, in the
year of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did for Herself, Her heirs and successors,
give and grant unto me, the said William Buck, Her special licence that
I, the said William Buck, my executors, administrators, and assigns, or
such others as I, the said William Buck, my executors, administrators,
and assigns, should at any time agree with, and no others, from time
to time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands,
and Isle of Man, an Invention for "IMPROVEMENTS IN MACHINERY OR
APPARATUS FOR LOCKING OR CONTROLLING THE HAND LEVERS OF RAILWAY POINTS
AND SIGNALS," upon the condition. (amongst others) that I, the said
William Buck, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
:

page_text: •
particularly describe and ascertain the nature of the said Invention,
and in what manner the same was to be performed, and cause the
same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said William Buck, do hereby declare
the nature of my said Invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement :—
My said Invention relates to certain peculiar arrangements and con-
structions of apparatus for locking or controlling the levers or handles
employed for working railway points and signals in such a manner that
only those signals can be given which correspond to the position of their
respective points, and that those point levers will be locked by the
movement of their corresponding signal levers, also that it shall be im-*
possible to give improper or conflicting signals from one and the same
set of levers, thereby relieving the signalman of much responsibility,
and ensuring the greater safety of the traffic upon railways, especially
where a large number of signals and points are worked from one spot.
The first part of my Invention consists in the use of "lever bars" or
bars working direct from the hand levers either vertically or horizontally
provided with longitudinal projections, keys, or lateral notches acting
upon triggers or cranks of a peculiar construction and arrangement for
giving motion to a series or tier of parallel sliding locking bars. The
said lever bars are to be provided with notches or stops for receiving
certain locks or projections attached to the sliding bars above referred
to. By this arrangement the "lever bars are caused to perform a
double function inasmuch as they not only serve to actuate the locks but
receive and are locked by the said locks.
"
The second part of my Invention relates to the mode of giving motion
to the sliding bars hercin-before referred to. This is effected by means
of the aforesaid triggers or cranks which work upon fixed centres, and
transmit the motion of the "lever bars" rapidly or suddenly at one or
both ends of the stroke of the hand lever, but are inoperative or at rest
during the remainder of the stroke. These triggers move the sliding
bars forward in one direction only, the backward motion being effected
by springs or weights.
The third and last part of my Invention is applicable when inclines or
wedges are placed on the sides or edges of "lever bars" for the purpose
1

page_text: of imparting motion directly or without the intervention of triggers or
cranks in one or both directions to the sliding bars, and consists in the
use of loose clips or shoes which are fitted on to the sliding bars, and
are capable of adjusting themselves to the various angles of the inclines
5 or wedges on the "lever bars."
.
-
In practice frames are placed on cach side of the sliding bars, such
frames being grooved or recessed either for the reception of the locks
attached to the sliding bars or for auxiliary locks working between' and
independently of the said bars...
When two or more levers operate upon the samo sliding bar an
auxiliary sliding plate or lock working between and independently of
the sliding bars may, if desired, be applied for the purpose of preventing
more than one of these levers being pulled over at the same time; the
"lever bars." in such case are provided with notches or projections which
either give. motion to the lock when it is free or form stops for the
"lever bars," against the lock, when it is fixed by another lever.. Ad--
ditional or extra locks may be applied if desired to the sliding bars after
the apparatus is fixed or at work without displacing the other locking
by introducing plates between the sliding bars, such plates being caused
..to butt at each end against the locks already fixed to the sliding bars;
or these additional plates may be secured to the sliding bars by means of
studs, bolts, or clips..
Having thus set forth the nature of my said Invention I will now
proceed to describe the same in detail, reference being had to the accom-
panying explanatory Sheets of Drawings..
Sheet 1 shews the general arrangement of one form of my improved
locking apparatus and its application to a set of ordinary hand levers;
Figs. 1, 2, and 3 represent different views of a portion of a frame of
fifty levers. Of these I will first describe what is shewn in Fig. 3'as-
the connection between the hand levers and the locking is therein most
conveniently shewn.
The upper part of these hand levers A may be of any form or length,
and I have shown one similar in this respect to those in common use,
but the lower arm B must be of sufficient length to carry the lever ·
bars O, C, which are shewn in a vertical position passing upwards
through the grooved locking frames D, D.
:
As I shall presently describe the manner in which these lever bars
actuate the "locking "contained in these frames it will be sufficient to

page_text: state here that the lever bars are notched, as shewn at c, c', as well as
at other parts between C, and O' and that the main locking is effecting in
these notches by the movement of the horizontal sliding plates or locks
b, b², bº, b³, bª, b³, and 6º, attached to their respective bars a, a¹, a³, a³‚ àª‚ à³,
and aº.
I will also state here that in this arrangement of locking as well as
in other modifications, which will be herein-after described, one lever
bar only is required for each hand lover whatever may be the number
of signals and points operated upon, whereby greater simplicity and
uniformity of the working parts are attained.
E
1
It is not essential that the locking frames D, D', should be placed in
the position shewn in Fig. 3, the locking being so constructed as to
work equally well with those frames placed either vertically, as shewn,
or horizontally if it is found convenient to place the locking under the
floor of the signal box. In the latter case the lever bars would be con- 1
nected to the hand levers at or near the dotted lines at d, and would
then work horizontally either in a forward direction d'or backwards ď³.
Again by lengthening the lower arm of the hand levers at E the lever
bar may be connected thereto and work downwards, in which case the
locking frames would be placed vertically beneath the floor of the signal
box. These are manifest advantages as it not always convenient or
practicable to place the locking apparatus in the same position in the
signal box.
Another advantage derived from this arrangement of locking is that
by lengthening the locking frames and lever bars any required number ด
of sliding bars can be added according to the number of levers in the
main frame or lever plate, and it will be herein-after seen that no com-
plication of the different parts of the apparatus will ensue from any
extra number of levers being placed in one frame.
I will now describe more particularly the "lever bars," one of which
is clearly shewn at C, Fig. 2. These bars may be connected to the
main or hand levers by a single joint, as shown at e, Fig. 3, the lower
part of the bar being reduced in thickness so that it will bend slightly,
thereby allowing the pin at e to move in the arc of a circle from e to e'.
This connection between the "lever bars" and hand levers may be made
otherwise, videlicet, by means of a double jointed connecting rod. In
the upper part of the "lever bars" are cut the notches for receiving the
locks. These notches it will be seen on reference to Fig. 2 are all on

page_text: the right hand side of the bars, but in some modifications of the locking.
which will be herein-after described, notches are required on both sides
of the "lever bars."
The angle irons G, G, Fig. 3; are for the purpose of keeping the
"lever bars" in their places. They are continued throughout the whole
length of the main frame, and on removing them the "lever bars" can
be taken out without disarranging the remainder of the locking.
Before explaining the manner in which the "lever bars" actuate or
give motion to the sliding.bars and locks attached thereto, I will
▸ describe how the sliding bars and locks are arranged and carried by the
grooved frames.
•
By referring to Fig. 3 it will be seen that the back frame D¹ is
fixed to the main lever frame or plate by means of the bracket f.
These back frames occupy the intervening spaces between and form
5 guides for the "lever bars," the spaces are shewn at g, Fig. 2, and
the plan Fig. 1 shews the frames in section at D' between the lever
bars C. Between the projections or teeth on the face of these frames
(shewn in Fig. 3 and at h¸ in Fig. 1) are the spaces or grooves in
which the locks move horizontally: The length of these frames and
O the number of teeth will vary according to the number of sliding bars
required. The front frames D, Figs. 1 and 3, are also provided with
grooves in which the opposite end of the locks slide horizontally. On
reference to Fig. 3 it will be seen that the locks b, b¹, bº, b, b', b,
and & support the sliding bars a, a³, a³, a³, a', a³, and aº, and being
5 fastened thereto allow them to move freely in a horizontal direction.
Should the distance along the sliding bar between any two adjacent
locks be greater than the bar will bear without bending or sagging, extra
plates are introduced similar in form to the locks, but so placed that
they will not act as locks, but simply as supports. Some of these plates
) are shewn at h, h, h, Fig. 2. Inasmuch as no strain is put upon these
sliding bars beyond the friction due to their own weight and that of the
locks the bars can be made thin in section, thereby occupying but
little space one over the other. This is an important advantage, as the
length of the locking frames and lever bars is determined by the
5 space occupied by the tier or series of bars, and the size and cost of
the whole apparatus is reduced in proportion to the compactness of the
sliding bars. The locks or locking plates project on each side of the
sliding bar, as seen at E, E, Fig. 1, and work in the grooves of

page_text: the frames D and D'. When two or more locks occur close together the
outer projection is not required, but the lock is made as shewn at E',
Fig. 1.
I will now explain the manner in which the lever bars actuate or
give motion to the sliding bars and locks attached thoreto by means of
triggers or cranks, as shewn on Sheet 1. I do not confine myself to
this method and will herein-after describe other modes of working
sliding bars, as shewn on Sheet 2.
"
Fig. 4, Sheet 1, is an enlargement of a portion of the apparatus the
details of which are similar to those of Figs. 1, 2, and 3 on this Sheet.
I may hero observe that I have not set forth or illustrated a combination
of interlocking apparatus specially adapted for any given number of
signals and points, but have simply described the essential features of
such an apparatus as may be readily adapted and applied to suit any
number of lovers required to work a junction or station, and which, when
so adapted, will properly fulfil all the requirements before specified. It
must be understood that in this view, as well as in Fig. 2, the grooved
frames are not shewn, but their spaces between the "lever bars are
left blank, and to render the Drawing less complicated only a few of the
sliding bars are shewn by dotted lines. In Fig. 4 four "lever bars"
are partly shewn. C' and C³ are for signal levers, C and C' for points.
For each point lever two triggers are required, and ³, k and ³, and one
for each signal lever, as at 1, P. On the face of the "lever bars" are
longitudinal projections or parallel square strips m, m, m, m, which for
convenience I call "keys." These are rivetted or otherwise fastened to:
the "lever bars" and are shewn at m, m, Fig. 1, with a trigger at k.
These triggers work on pins fixed in the front and back frames, onc
of which is shewn at n, Fig. 3. To the sliding bars aro fixed the
driving plates or brackets o (Figs. 1 and 4) somewhat similar in form
to the locks against which the shoulder of the trigger bears. Theso;
brackets may also act as locks when necessary as at p (Fig. 4). The
"lever bars as before explained work in correspondence with their
respective hand levers and move upwards when the levers are pulled
over. The "lever bar" C³ (Fig. 4) is down in its normal position and
it will be seen that the slightest upward movement will cause the trigger:
to push the locks p, p³, into their notches, thereby locking the "lever
bars" C and C'. If the upward movement of the "lever bar" be
continued the trigger will be raised as at k and the locks thrust home as
"

page_text: •
at q. When the triggers rest as shewn in Fig. 4 on the upper or
lower ends of the keys the locks are "off," and when they rest against
the side of the keys the locks are "on" and the sliding locking bar
is effectually and immoveably. blocked throughout the intermediate
portion of the stroke of the lever, as will be seen on referring to
the Drawings. The triggers and keys are so proportioned that the
locking is completed when the lever has moved about one-tenth part of
its stroke. When the "lever bars" are lowered back; to their normal
position the top triggers fall by reason of their own weight, but the
O sliding bars and locks receive their backward motion from the springs F
(Fig. 1) or by means of weights or any other suitable contrivance...
Thus it will be scen that the locking is effected by the pressure of the
keys against the triggers and the unlocking by springs or weights
which cause the sliding bars to follow up the triggers when they fall.
5 The top triggers l;'i, k, and l^, are for the purpose of “locking”.v
"when
their respective levers are out of their normal position, while the bottom
triggers and ³, which are used only with points, are for "unlocking"
when their respective levers are "over" and the "lever bars" raised
to their full extent. Thus it will be seen that the key m on the
0 "lever bar" C, which is raised to the end of its stroke, retains the top
trigger in such a position that the locks which it works are "on"
while it allows the bottom trigger to rise and its respective locks to
.come "off". as-at.r. The springs or weights at the ends of those
sliding bars which are worked by the bottom triggers must be sufficient
5 to raise those triggers from; the position shewn at ♬ to that shewn at k².
In order to trace the action of, the locking in Fig. 4. it must.be
observed that the signal "lever bar "C' is locked and cannot be moved
until the lever bar C³ is raised like C to the end of its stroke and the
trigger with its lock is in the same position as k¹, all the locks are
0 then off, and the lever bar Cis free to move. C³ and. C', as before
stated, are "point" "lever bars," and the signal attached to C requires
both, these "points" to be set or pulled over before it can be moved
or "lowered.". Directly the signal "lever bar". O' is moved from its
normal position the trigger 2 locks C' at r, and C³ will also become
5 locked by a entering the notch t, which will have been raised to a
position opposite 8. The trigger 2 will also lock C³ by means of the
lock u. Thus it will be seen that the movement of one trigger and
one sliding bar will simultaneously lock some lever bars in their normal
position, and others that have been moved from their normal position.
.
"

page_text: I am aware that it has been proposed to actuate a sliding locking bar
by what has been termed a "cam piece" or "tumbler" worked from
the catch of the sliding bolt of the hand lever, but this arrangement is
faulty since the levers can be locked or unlocked without the sliding
bolt being in the notch, whereas according to my arrangement and mode
of actuating the trigger I am enabled to obtain a perfect locking at both
ends of the stroke, the said locking being dependent not upon the position
of the catch of the sliding bolt but upon the position of the hand lever
itself. Moreover, by the use of triggers arranged in the manner herein.
before described and illustrated by my Drawings, all chance of the
apparatus becoming injured or strained, in the event of any of the
levers not getting well home, is obviated, which constitutes an important
advantage over the arrangements hitherto employed.
A similar combination to that herein-before described of "lever bars "
and triggers may be employed for imparting motion to the parallel :
sliding bars marked 1 to 10 in Fig. 2 (Sheet 2) of the Drawings
referred to in the Specification of my Patent No. 1013, A.D. 1868,
instead of the wedges or inclines shewn therein. These parallel sliding
bars thus actuated transmit their motion to the "locking shafts "
rocking shafts carrying locking wings or brackets in the manner
described in the said former Specification.
or
In Fig. 13 & 14, Sheet II., I have shewn in sectional elevation and
plan how this combination is effected. The hand lovers a, a, a, a,
are shewn in their normal position. B is a portion of a lever bar
coupled at one end to a hand lever and having a projecting flange or 2
key 6' for moving the trigger c. The sliding bars, one of which is
shewn at d, are actuated by the triggers in the manner before described
in this Specification, and have brackets or lugs projecting upwards as
at e. These lugs bear against the plates f,f, which are attached to the
locking spindles g, g. When the trigger is pushed forwards by the lever 8
bar these spindles turn or partially rotate on their bearings h, h, and
the lock is raised from an inclined to a horizontal position, as shewn in
the section. The action of these locks is fully described in my said
former Specification, and it will be sufficient here to observe that their
weight is available and found to be sufficient for pushing back the 3
sliding bar and its trigger or triggers when the locking is "off."
Fig. 7 shews how by a further slight alteration in the form of
trigger a single sliding locking bar may be worked for locking and

page_text: unlocking two or more levers by one trigger. The method of working
the lever bars and the details of the grooved frames may be assumed to
be the same as beforo described. The alteration is in the form of the
triggers and keys attached to the point "lever bars" J, K, L. The lever
bar J is in its normal position, K is half raised, and L is fully raised to
the end of the stroke. The triggers are single acting, that is to say,
they work the bars in one direction only, and weights or springs aro
used to bring them back. The signal lever bars H and I work their
sliding bars by means of the keys and the triggers a and b, which are
precisely similar to those before described. These lever bars have
notches on both sides. The trigger c is shown in its normal position
with the locks ƒ and g fully "on" and fully "off" respectively. The
trigger d is shewn at half-stroke with its locks h and i half "on" and
half "off," and the trigger e is shewn at the end of the stroke of the
lever bar L with its locks and fully "off" and fully "on" respec-
tively. Thus the locking and unlocking of several levers may be
effected by one trigger and one sliding bar. These triggers c, d, and .e.
are each provided with a notch in the face for the upper end of the key
to act upon, as shewn at c. Stops or guards m, n, o, are fixed on the
sliding bars at the back of the keys to ensure the return of the locks by
the action of the inclines on the keys in case the springs or weights fail
in their action. By comparing the relative positions of the threo
triggers c, d, e, it will be seen that at the commencement of the stroke
of the "lever bars" the keys bear against the notch in the triggers,
thereby giving a slight motion to the sliding bars. When a small
portion of the stroke is completed the notch becomes disengaged from.
"the end of the key and the trigger rests during nine-tenths of the stroko
against the side of the key as at d. As the end of the stroke is
approached the projecting end of the bottom of the key raises the trigger
and completes the locking or unlocking.
:
I wish it to be understood that I lay no claim to the system of.
locking and unlocking by means of a single trigger having two impulses
so as to half-lock or unlock at the commencement and then to complete
the locking or unlocking at the termination of the stroke separate and
apart from the use of the peculiar form of trigger which I have described
with reference to Figure 7.
...
In lieu of having a longitudinal projection or key m (Fig. 4, Sheet I,)
attached to the face of each. "lever bar" for the purpose of actuating

page_text: the triggers notches may be made in the side of the "lever bar" for that
purpose.
Figure 9 (Sheet 2) shows a method of working the sliding bars in
both directions by means of wedges or inclines and without springs or
weights, which method is not in itself new. The improvement consists {
in the application of loose clips or shoes p, p, q, q, r, r, which bear
against both sides of the keys. They have large bearing surfaces, and
will adjust themselves to the inclines of the keys. The "lever bars"
and locks shown in this Figure being precisely the same in number and
position as those in Figure 7 (p, p, being in the normal position, q, q, at 1
half stroke, and r, r, at the end of the stroke,) they need not be further
described, and as the details of the grooved frames, and the working of
the lever bars are the same as before, I have not deemed it necessary to
show a plan or any other views of this arrangement.
"'
Figure 8 shows the application of the aforesaid shoes to wedges or 1
inclines when formed in the side of the lever bars themselves. In this
case the sliding bars are brought back by springs or weights as the
wedges move the bars in one direction only. M is a signal "lever bar"
with a V notch or incline cut in the side of the bar into which the shoo
enters. When the lever bar is raised the shoe is pressed back and moves 2
the sliding bar by means of the projecting plate v. N is a point lover
bar" acting upon two shoes and provided with two inclines and u
working separate sliding bars. These shoes are equivalent to the top
and bottom triggers before described and shown in Figure 4. The lower
shoe and sliding bar may be dispensed with by clongating the V notch 2
from t to u, as shown by the dotted line w. The action of "locking
and "unlocking" will then be effected by one sliding bar, as shown in
Figure 7, where one trigger is employed. It is clear that the large
surface of the shoes or clips presented to the inclines will ensure their
wearing for a long period, but they may be easily taken out and rc- 30
placed by new ones without disarranging the remainder of the locking
by removing the angle irons shown at G, G, (Figure 3) and drawing back
the lever bars.
'

page_text: details of locks and grooved frames though not shown in this view may
be taken as substantially the same.
It frequently occurs that of two or more signal levers actuating the
same number of locks and locking the same levers only one ought to be
capable of being pulled over at a time. In such case instead of using
two or more sliding bars, each carrying the same locks, I employ one
bar for the whole, and place an auxiliary sliding plate or lock between
the lever bars to prevent more than one of the said levers being pulled
over at the same time. I lay no claim however to the action of these
auxiliary locks, but merely refer to them to point out that my arrange-
.ment of locking apparatus admits of their application in such a form and
position that instead of occupying extra or available space they can
work between the sliding bars, thereby economising space and reducing
.the number of the working parts of the apparatus.
O, P, Q, (Figure 5) are signal "lever bars" which work the same
sliding bar x, x, by means of the three separate triggers. The auxiliary
sliding plate or lock y, y, (Figures 5 and 6) is formed of a solid plate.
It is fitted into the grooves of the locking frames and slides easily at
right angles to the lever bars when operated upon by any of the V notches
) or inclines cut in the sides of those bars, as shown in the Drawing
(Figure 5) the lever bar P can be raised and its notches will pass the
lock y, y, without moving it, but the parallel sides of the bar will hold
the lock so that neither O nor Q can be raised. In like manner when O
is lifted P and Q become locked, and when Q is lifted O and P become
5 locked. Another lock of the same kind is shown at z, z, z, in Figure 5.
This lock is also in one piece and is for the purpose of locking the lever
bar R. To this bar is attached the signal which acts as a " distant to
each of the three signals working with O, P, Q, and it is requisite that
one out of the three latter should be "given" before the “distant" can
O be pulled "off." Now it is a common practice in such a case to use
three levers to work the distant signal all working on the same wire,
but by the application of this lock I am able to work the distant signal
with one lever only, which stands locked until one of the three lever
bars O, P, Q, is raised. By means of the spring a' the lock is kept in
5 the notch ở³, until moved out of it by one of the V notches or inclines in
the other "lever bars" at 6, 6³, or 6'. When the bar Q for instance is
fully raised the lock will be half-way out of the notch 6³, and the
notch will be opposite z. The "distant"-" lever bar". R is then and
.
"

page_text: then only free to move, but in doing so the V notch or incline b¹ carries the
lock further forward and causes it to enter the notch c'; by this means
the "distant" locks the "home" signal when both are given, and it is
impossible to leave the distant signal at "all right" when the "home"
signals are at "danger."
In Figure 6 d', d³, are the grooved frames shown in section. The
lock y slides in the grooves a, a, a, a.
The "lever bars" and keys are
shown at e¹, e³, e³, and the V notches by shading lines; b, b, is one of the
sliding bars which works independently and is not connected in any way
to the lock y.
Figures X., XI., XII., illustrate two modes of applying additional or
extra locks to an apparatus constructed according to the principles an
details which I have herein set forth. These locks are of such a form that
hey can be put in after the apparatus is fixed or at work without dis-
arranging the other locking, and are for the purpose of making good any
deficiency or omission in the locking which may be discovered after the
apparatus is fixed or at work.
"3
"
Figure X. shows a number of "lever bars in transverse section
working between the front and back grooved frames. The sliding bar
ff, has two ordinary locks attached at g, g, which lock the "lever bars'
h, h. S, S, is an extra lock put in for the purpose of causing the sliding
bar to lock the "lever bars" i, i. The ends of this lock butt against the
locks g, g, and suitable projecting pieces are formed upon it for working
in the grooved frames which serve to support it. By removing the front
grooved frames k, k, k, k, this lock can be put into its place underneath
the sliding bar, as shown at o, o, Figure XI.
In the event of the above arrangement not being convenient another
method of fixing an extra or additional lock to a sliding bar may be
applied as shown in Fig. XII. In lieu of its ends abutting against the
existing locks above described this lock is furnished with studs m, m,
bearing against one side of the sliding bar T, and also with a stud /
fitting into a notch cut in the opposite side of the bar. This lock also
slides in the grooves of the locking frames, as before described, and can
be put in its place by removing the front frames. A front view of this
lock is shown at n, Figure XI.
Having now particularly described my said Invention and the mode of
carrying the same into effect, I would observe that the details 'may be
varied and the proportions altered to suit the various requirements of
3

page_text: signalling and interlocking of point and signal levers which are now well
understood. I have not therefore set forth any special combination of
locking precisely adapted to any particular junction or station, or to any
given number of points and signals, but have explained the various parts
of an apparatus capable of being readily applied to any required number
or arrangement of levers.
I do not claim as my Invention the separate use of sliding locking
bars, nor what I have called auxiliary sliding plates or locks, nor the
manner in which the lever bars work such auxiliary locks, nor do I
claim the use of "lever bars," that is to say, sliding bars attached to the
levers.
But what I do claim as my Invention is,-
Firstly. The use of "lever bars" connected to the main body of the
point and signal levers having longitudinal projections, or "keys,” or
notches for working detached triggers or cranks which give motion to
sliding locking plates or bars carrying locks, taking into notches formed
for their reception in the said lever bars, the whole being combined
together and arranged to operate substantially in the manner herein-
before described and for the purpose specified.
Secondly. The use of detached triggers or cranks so arranged as to
transmit the motion of the "lever bars" rapidly and suddenly to the
sliding locking bars herein-before referred to, or to the parallel sliding
bars referred to in the Specification of my said Patent No. 1013, A.D.
1868, at the commencement of the stroke of the hand lever and to hold
; or block the said sliding bar securely during the remainder of the stroke,
as and for the purpose herein fully set forth.
Thirdly. The application of loose clips or shoes to the sliding locking
bars capable of adjusting themselves to the various angles of the inclines
or wedges on the "lever bars" when such are employed for giving
motion to sliding locking bars.
In witness whereof, I, the said William Buck, have hereunto set
hand and seal, this Twentieth day of May, in the year of
our Lord One thousand eight hundred and seventy-one.
my