AN IMPROVED REVERSIBLE SWITCH Box FOR RAILWAYS
Year: 1876

page_text: LETTERS PATENT to William Silver Hall, of Nuneaton, in the County of
Warwick, Engineer, for the Invention of "AN IMPROVED REVERSIBLE SWITCH
Box FOR RAILWAYS"
Scaled the 20th February 1877, and dated the 29th August 1876.
PROVISIONAL SPECIFICATION left by the said William Silver Hall at the
Office of the Commissioners of Patents on the 29th August 1876
WILLIAM SILVER HALL, of Nuneaton, in the County of Warwick, Engineer.
"AN IMPROVED REVERSIBLE SWITCH BOX FOR RAILWAYS."
This Invention of an improved reversible switch box for railways relates more
especially to railway switches and points which are frequently used as facing points
and which require to be set alternately in different directions to facilitate the
operations of shunting. Such points are ordinarily worked by means of a weighted
lever or levers which have a constant tendency to bring them back to one position,
which I will suppose to be fair for the main hne; should it be desired for shunting
or temporary purposes to set them fair for the branch line the presence of a man to
hold them in that position is necessary.
By the application of my Invention it is possible instantaneously to change the
bias of such lever or levers so that they will, until again changed, tend to set the
points fair for the branch line; at the same time should an engine or other vehicle
or vehicles pass in the opposite direction from either main or branch line these
points will yield in the same manner as ordinary trailing points, returning after the
said vehicle or vehicles have passed to the position in which they were set. I am
well aware that apparatus to effect a similar purpose has already been in use, but
heretofore the bias of the lever in one direction or the other has been determined
by causing the weighted arm of the lever to revolve horizontally upon a vertical
axis, or by forming the weighted lever with a slotted eye, which will allow it to
enter or leave certain notches, and therefore I make no claim to
any such arrange-
ments.
By the method which I adopt the weighted lever is capable of partial revolution
around the main axis or fulcrum, and is provided. with projections or stops which
at the extreme points of the rango permitted to it come in contact with a projecting
portion of the main lever, which it cannot pass. I further provide a small sliding
Price fid

page_text: block on the main lever, which has to be raised before the weighted lever can be
swung over to its opposite position, thus obviating all possibility of the weighted
lever being jerked over into the opposite position by the rapid passage of a vehicle
or train over the points in a trailing direction.
Where required I further provide means for locking the said sliding block and
preventing the alteration of the weighted lever except by an authorized person
carrying the proper key, while at the same time allowing the points to be shifted
by hand in the usual manner for any temporary purposes.
The apparatus is fixed up in an iron standard box, as usually employed for this
purpose; the central pin round which the motion acts carries an upright main lever,
and also projecting at light angles from this pin is the weighted lever.
The lower part of the main lever is in a different plane from the upper part of
the handle, and on the back part of the weighted lever is a projection extending on
both sides of the centre and projecting into the same plane as the lower part of the
main lever; a block slides on the main lever and prevents the weighted lever from
being thrown entirely over or through an are of 180° except when the block is
raised, a slot is in the main lever for a cotter to pass through, which has a hole for
a padlock, to render it impossible for any person not having the key to raise the
block and reverse the weighted lever so as to alter the bias of the weight' which
thus acts in the reversible or opposite positions by the same main lever, as the
'weighted lever is on one or the other side of the axial central line on which the
main lever works.
The points can be worked from the weighted lever itself if desired when locked
to the main lever by the sliding block by a handle provided on the weight.
The switch box by connecting rods may work at any angle with the rails, but it
is preferable to fix the apparatus so that the levers vibrate at right angles to the
line of rails, so that the driver or brakesman may see which way the points are set,
the disc lamp or other usual contrivances being added as desired or connected with
a semaphore.
It will be understood that the weighted lever being capable of partial rotation on :
the same axis as the main lever in one position is also capable of acting in the
other position when, as described, the weighted lever is thrown over through an arc
of 180°, and that the sliding block ensures the retention in the position required,
and that this applies also to the working of the semaphores where two opposite
indications are desired to be shown.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said William Silver Hall in the Great Seal Patent Office on the 21st
February 1877.
WILLIAM SILVER HALL, of Nuneaton, in the County of Warwick, Engineer.
"AN IMPROVED REVERSIBLE SWITCH BOX FOR RAILWAYS."
This Invention relates more especially to railway switches and points which are
frequently used as facing points and which require to be set alternately in different
directions to facilitate the operations of shunting. Such points are ordinarily
worked by means of a weighted lever or levers which have a constant tendency to
bring them back to one position, which I will suppose to be fair for the main line.
In some cases the weighted lever is so arranged that its bias can be altered so as to
set the points fair for the branch line This may be done in various ways -For
instance, by causing the weighted lever to revolve around the main lever in a
horizontal or nearly horizontal plane, by providing the weighted lever with a
slotted hole to allow an endways motion by which it is withdrawn from a notch, by
jointing the weighted lever at or above the fulcrum pin, so that it can be turned
over to the opposite side, or by any other well-known method, to none of which as
heretofore adopted do I lay any claim.

page_text: In my improved switch box I make the main handle continuous on both sides of
the fulcrum pin, the lower end of it being connected (either directly or through the
medium of a bell-crank lever or equivalent contrivance) with the switch rod, while
the upper end may be formed into a handle at a convenient height for moving the
points The weighted lever is so formed as to turn over. by the side of the main
lever and to engage itself with the lower part of the same by means of suitable
projections in such a position as to stand at an angle of ninety degrees or there-
abouts (as may be found most convenient) with the said main lever and on either
side of it, as may be desired. On the main lever is a small sliding block or drop
weight, when this drop weight is raised by sliding it upwards on the main lever
the weighted lever can be turned over, as above described The drop weight is so
formed as to ride on a projecting portion of the weighted lever until the same has
been completely turned over, so that it is not necessary for the pointsman to hold
up the drop weight while turning over the lever, except at the commencement of
the motion. When the weighted lever has been completely turned over towards
either side the drop weight falls of itself into a position which locks the two
levers rigidly together, and effectually prevents all jar and back lash and all
possibility of the weighted lever being jerked over into the reverse position by the
rapid passage of a train through the points in a trailing direction.
Another and most important object of this weight is to enable the switch box in
whichever direction it is weighted to be handled in the same manner and with the
same facility as an ordinary box with rigid handle, without throwing over the
weighted lover.
If preferred the main lever may be cut off at a point slightly above the drop
weight, and in this case the switches may be worked by a handle formed on the
weighted lever, and may be held by the pointsman in either position without
throwing over the weighted lever.
I further provide when desired a slot or hole in the main handle, through which
a cotter, padlock, or similar contrivance may be passed, thus rendering it impossible
for any one not intrusted with the key to alter the bias of the points, while at the
same time the points may be handled in the ordinary manner.
I also provide a method by which my improved switch box may be converted
into what is known as a "knob-up box." For this purpose I cut a central recess in
the projecting curved part of the weighted lever on which the drop weight rides
during the process of turning over the weighted lever, but of such a width and
form that the drop weight in its ordinary position will still ride over it. This drop
weight is so formed that it may be drawn off the main lever and slipped over it
again in the reverse position. The part which in this reversed position rides over the
curved projection is so formed that it drops into and engages with the said central
notch, thus fixing the weight in a central or neutral position and enabling the
pointsman to rapidly reverse the position of the switches with a very slight exertion
of power.
If it is desired a semaphore, signal lamp, or other apparatus for indicating the
position of the switches may be attached to the moving parts of the switch box in
any well-known manner.
The Invention will be more clearly understood by reference to the Drawings
hereunto annexed forming part of this Specification, the same letters of reference
indicating corresponding parts in all the corresponding Figures.
Figure 1 is a side elevation; Figure 2 is an end elevation (partly in section); and
Figure 3 is a plan of my improved switch box. A. is the fulcrum pin or main centre;
B is the main lever and O the weighted lever and D the frame or box carrying
them; E is the sliding block or drop weight, which when down locks the two levers
rigidly together; by raising the weight E the weighted lever C is liberated and can
be thrown over into the position C, the weight E riding over the curved projection c, c,
until the weighted lever has arrived at the opposite position, when the sliding block
again drops and locks the two levers rigidly together; F is a cotter and is a
padlock which prevent any person not entrusted with the key from altering the
.

page_text: bias of the points, while at the same time the points can be handled in the ordinary
manner by means of the lever B. If preferred the lever B may be cut off at the
point X-X, in which case the points may be handled by the handle c, c, c, on the
weighted lever:
Figure 4 is a detached view of part of the main lever and sliding block as
modified for a "knob-up box," e being the projecting tongue of the block E for
engaging in the central notch of the weighted lever.
"
Figure 5 is a similar detached view of the weighted lover C showing the central
notch c in the curved projection.
Figures 6 and 7 show (both in plan and elevation) a set of points controlled by
my improved switch box, Figure 6 showing the points with a bias to stand fair for
the branch line, and Figure 7 with a bias for the main line Figures 6 and 7 also
show one method (out of many which might be adopted) for connecting the moving
parts of the switch box to a semaphore or signal. In this arrangement the main
lever is keyed fast to the contre pin or fulcrum, the head of which is formed into a
small crank connected by a rod to the indicating arm of the semaphore.
Having now particularly described and set forth the nature of the said Invention,
and in what manner the same may be performed or carried into practice, I wish it
to be understood that what I claim and desire to secure in the said in part recited
Letters Patent is,-
First. The arrangement of switch box, of which the bias may be instantaneously
reversed (or neutralised by being converted into a "knob up"), while at the same
time it may be handled with the same facility as an ordinary switch box with rigid
handle and weight, substantially as described.
Second. The use of the wedge-shaped drop weight forming a rigid connection
between the weighted lever and the main lever, for the purpose of preventing the
possibility of the weighted lever being accidentally reversed or jerked over by the
passage of a train in a trailing direction, substantially as described.
Third. The means indicated for securing when necessary by a padlock or other
apparatus with a key the said drop weight, so that the weighted lever can only be
reversed by the person entrusted with the key of the locking apparatus, while at
the same time the ordinary handling of the points is not interfered with, sub-
stantially as described.
In witness whereof, I, the said William Silver Hall, have hereunto set my
hand and seal, this Fourteenth day of February, in the year of our Lord
One thousand eight hundred and seventy-seven.
Witnesses,
CHA. D. WEST,
G. J. PLAYER.
WILLIAM SILVER HALL. (L.S.)