Improvements connected with the Sliding Windows of Railway Carriages or other Vehicles or Vessels.
Year: 1897

page_text: Date of Application, 28th April, 1897-Accepted, 14th Aug., 1897
COMPLETE SPECIFICATION.
Improvements connected with the Sliding Windows of Railway
Carriages or other Vehicles or Vessels.
I, JACQUES AUGUSTIN NORMAND, of 67 Rue du Perrey, Le Havre, in the Republic
of France, 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:-
The sliding windows of railway carriages are now generally so arranged that the
currents of air which are due to the motion of the train and which are generally
charged with dust and cinders, enter the carriage when the window is opened and
violently impinge on the passengers seated near to such window and facing the engine
so that the window is frequently allowed to remain closed when otherwise it would
be very desirable that it should be open. Even in the winter time it would frequently
be desirable to open the window but this is not done because then, however little
the window might be opened the comparatively warm air in the interior would at
once be displaced by cold air from without, the air being apt to rush in with some
violence even when the wind is blowing on the side of the train opposite to that on
which the window is opened, because the vertical rear portion of the window frame
is in a plane perpendicular to the longitudinal axis of the carriage and, therefore,
drives back, inwardly, the whirling gusts of air set up by the rapidly moving
train.
These inconveniences I propose to remedy by increasing inside the carriage the
thickness, or depth, of the vertical portions of the stationary frame of the sliding
window, and by imparting to the inner vertical walls of such frame, or, at all events,
to the one wall which receives the impact of the wind produced by the train in
motion-an outwardly diverging shape or outline.
In the accompanying drawings, Figures 1, 2 and 3 represent one of the existing
arrangements of railway-corridor carriage doors with sliding windows.
Figure 1 is a vertical elevation of the top-part of a carriage door with a sliding
window, viewed from within, with the window lowered.
Figure 2 is a vertical section thereof, on the line X X and,
Figure 3 is a horizontal section on the line Y Y.
Figures 4, 5 and 6 are, respectively, an elevation and the two corresponding
sections of a part of a carriage door shewing a manner in which my Invention may
be applied thereto.
By comparing the old and the new construction it will be seen that in the latter
the parts A A¹ Figures 1, 2 and 3, which at present form the inner slide-ways of the
window sash, are altered to the shape B B¹, Figures 4, 5 and 6, so as to impart an
outwardly diverging form thereto. An appreciable benefit will thus be obtained,
whatever the shape of the pieces B B', provided the horizontal lines W W and Wi Wi
Figure 6, are tangents to the inner and outer vertical edges of the door frame,
diverge towards the outside of the carriage. But the maximum effect of the
improvement will be attained when the wind, the supposed direction of which is
marked by the line Z Z, Figure 6, impinges on the said pieces B B¹ at an angle
which shall cause it to be repelled towards the carriage exterior.

page_text: The advantage offered by the novel arrangement is obvious.
Supposing the air currents produced by the speed of motion, to be passing from
the right to the left, then the increased depth of the vertical portion of the frame
will diminish the bulk or volume of the air, which will enter the carriage obliquely,
without striking the inner rear wall of the frame. The air that strikes the said wall
cannot find its way into the interior of the carriage, being repelled by the oblique
form of the surface of B upon which it impinges, but, even though a small portion
of such air should enter the carriage, dust and cinders, owing to the inertia thereof,
will not enter therewith.
The smaller the longitudinal distance between the edges of the inner pieces B B¹,
and, the greater the transverse distance between the edges of B B' and the outer
surface of the carriage, the more certain will be the beneficial action. The former
distance should, preferably, not be less than the clear width of the window pane, so
as to avoid obstructing light when the window is closed. As to the last mentioned
distance, it will be the greater, the farther the pieces B BI project inwards, though,
of course, they should not project so far as to be in the passenger's way.
They are not in the way, as shewn in the drawings, because they do not project
inwards further than the arm rests generally fixed in the carriage and when the door
is opened, as shewn in dotted lines in Figure 6, they do not reduce the width of the
aperture.
External vertical screens could also be placed, as already tried, so as to project on
the outside surface of the carriage; but these screens are nearly useless since they
cause whirls in the air passing along the train.
Given an equal thickness, or depth, of the stationary frame, involving the same
reduction of the passengers field of view, a projection into the interior of the carriage
will prove far more effective than an outward projection.
A further advantage of the pieces B B' is that they effectively intercept the
sun-rays which would otherwise enter from the sides of the curtain, when it is drawn
down.
Where the relative dimensions of the parts are as shown in the drawings, the
desired result will be attained, even with a transverse wind of medium strength,
blowing from without at a speed of, say 4 metres per second. The resultant
(ZZ Figure 6) of this and that due to the motion of the train, which is estimated
at 19 metres per second (or 68 kilometres per hour), would suffice to exclude the
wind from the interior.
Considering that the angle formed by the lines Z Z, Figure 6, with the longi-
tudinal axis of the carriage is the smaller, the greater the speed with my Invention
it will be found, that, with the wind in about the average condition, the amount of
air that will find its way into the carriage, will be the less, the greater the speed of
the train; which is the reverse of what is actually observed.
Generally the arrangement according to my Invention will permit the window to
be opened on either side of the carriage, without creating any whirling currents of
air in the carriage and even under unfavourable circumstances, the total or partial
opening of the window will be attended with far less inconvenience than at present
is the case.
I have referred to a window fitted in a carriage-door, but my Invention can also be
applied to windows provided in stationary parts, or fixtures.
The pieces B, B₁ may be fixed or adjustable or removeable, and adapted to be
placed in the position most favourable under the conditions such as the direction in
which the train is moving at the time and then the slight reduction of the field of
vision, which the piece B¹,-secured to the vertical portion of the frame (which is
not receiving the impact of the wind at the time),-would otherwise occasion, can be
obviated; but, on the other hand, this slight advantage is amply compensated for, in
the case of stationary parts by the simplicity and strength, and by the fact that they
require no manipulation whatever.
The arrangements hereinbefore described can be applied either to new carriages or
to existing carriages the requisite, alterations being extremely simple, since they

page_text: consist in changing the small wooden pieces A A¹ Figure 3. My Invention is
especially adapted for use with railway carriage windows but it may also be applied
to windows in other carriages or vessels.
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 :-
In connection with the windows of railway carriages or other carriages or vessels
the application to the vertical side or sides of the window frame or guides of pieces
arranged as and for the purpose hereinbefore described.
Dated this 26th day of Apr
XV
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.