Balanced Safety Gear for Operating Bulkhead Doors of Ships.
Year: 1896

page_text: PROVISIONAL7
Balanced Safety Gear for Operating Bulkhead Doors of Ships.
ROBERT BAIRD 12 Percy Street Paisley Road West Glasgow Engineer do
hereby declare the nature of this invention to be as follows:-
This invention bas for its object means by which doors in ships' bulkheads may
be closed, by the flooding of the compartments connected by such doors.
I accomplish this by attaching to the bulkhead or any other suitable part of the
ship, at some distance, or immediately below the door a water-tight casing, which
contains a tank or float-from which a spindle passes through a gland in the top of
the casing. This spindle is connected to the bulk-head door by either rods, rope,
or chain, in conjunction with cranks or pulleys. The travel of the door as com-
pared with the tank may be multiplied by means of differential pulleys or levers,
so that a movement of one foot up or down of the float or tank may cause the
bulkhead door to move two or three feet.
The water is admitted to the water-tight casing in the event of flooding by non-
return-valves, which are fixed on each side of the casing and open to the
compartments on either side of the bulkhead. Thus if an accident occured
whereby one compartment was flooded the valve on that side would admit water to
the casing,
when the tank would be floated up or sufficiently lifted to let a vertical
door drop into its seat.
To increase the facility by which vertical sliding doors may be moved when
connected with such safety tanks-I arrange the weights of the door and the
tank, so that the one balances the weight of the other.
With the gear multiplied to increase the travel of the door as compared with
the tank a leverage is obtained whereby the door is easily moved up or down.
When the watertight casing is being filled with water the air is allowed to
escape by a tube having its outlet above the water level.
A float or tank contained in a water-tight casing as described may be used as a
means of shutting doors without any of the compartments being flooded, by having
a connection either with the sea, or deck tanks-the water being let off from the
casing when the operation is complete.
The following description of a method of applying and working the balanced
safety gear on an ordinary vertical sliding bulkhead door, will make my invention
better understood.
Supposing it is a door enclosing an alley-way; tunnel or coal-bunker with the
bottom of the door about one foot above the floor level. I bring the top of the
water-tight casing close to the bottom of the framing, in which the door slides,
using the bulkhead on one side and the flooring of the frame next to the bulkhead
on the other as the sides of the casing, and in each I place a hinged valve known
as a clack-the valves opening so that water passing into the casing from either
side of the bulkhead is trapped, and cannot get out unless by some arrangement
for the purpose, or the forcible opening of the clack-valves.
The float inside of the casing I preferably make in the form of two tanks
connected with a bridge to which the guide rod or spindle is attached-this
eaves room for the framing and free movement of the clack valves, also for
leaning purposes. The spindle passes through a gland on the cover of the

page_text: casing which guides the float when it is moved up or down. To the outside
end of this spindle I fix a wire rope which is led up, and partly round a pulley
(where it is fixed) of about twelve inches in diameter. This pulley revolves on a
spindle which is attached to the bulkhead above the door, at a height sufficient to
clear the door when it is up to its fullest extent, and is connected with the half
segment of another pulley about three times its diameter, which carries a wire rope
that is fixed to the door at one end and the pulley at the other, so that when the
float inside of the casing moves up or down, the rope on the half segment travels
three times the distance.
The bulkhead door being slung by a rope would rattle in a sea way. To
prevent this I provide steadying guides which work in a slot in the sides of the
door.
Doors, as herein before described being balanced with a leverage in favour of
the door, are at all times easily moved either by hand, or other attachment, which
may communicate with other parts of the ship.
ROBERT BAIRD, 12 Percy Street, Paisley Road, West, Glasgow 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 :-
This invention has for its object means by which doors in ships' bulkheads may
be closed, by the flooding of the compartments connected by such doors. I
accomplish this by attaching to the bulkhead or any other suitable part of the
ship, at some distance or immediately below the door, a water-tight casing, which
contains a tank or float, which may be so weighted that it will not rise to the
surface of the water, without a counterbalancing weight such as the door. From
this float a spindle or other attachment passes through the top of the casing, and is
connected to the bulkhead door preferably by rope or chain in conjunction with
levers or pulleys. The travel of the door as compared with the float is multiplied
by means of pulleys or levers, so that, comparatively, a movement of one foot of
the float, will cause the door to move two or three feet, or more or less as
required.
Water is admitted to the casing containing the float by non-return valves from
either side of the bulkhead, one valve being connected to an opening through the
bulkhead, and communicating with the compartment adjoining the one in which
the casing is placed, and the other valve on the casing, so that the flooding of
either of the compartments with which the doorway communicates, will have the
effect of closing the door by the water being admitted to the casing by either of
the non-return valves, whereby the weight of the float will be relieved sufficiently
to allow the door to fall to its seat.
Any water that is admitted to the casing cannot get out again except by a way
provided for the purpose, so that there is no through connection by the casing,
which would allow the water to flow from the one compartment to the other.
In order to particularly describe the nature of my invention, I will do so with
reference to the accompanying drawings.
Fig. 1. is a side sectional elevation on line d. d. Fig. 2. of my operating gear
attached to a bulkhead door, also shown in section.
Fig. 2. is a front elevation of gear and door.

page_text: guides and door.
The same letters of reference indicate corresponding parts on Figs. 1. 2. & 3.
The drawings may be taken as applied to a door, for closing the opening to the
shafting tunnel of a steam ship, and the line marked W. as the floor level (that
is to say the platform immediately above the flooring plates of the frames of
the ship).
What is termed water-tight casing throughout this description is marked L. on
Figs. 1. & 2. and what is termed tank or float, and described as being contained
in the water-tight casing is marked M. and shown in side sections of casing L. at.
Figs. 1. & 2.
To leave room for the non-return valves marked V. on Figs. 1. & 2. the tank
or float M. is in two sections as shown at Fig. 2. and is connected by bridge.
piece (). Figs. 1. & 2.
The tank or float M. is carried by rod N. which is fixed to bridge piece O. and
passes through the cover of the water-tight casing L.
To the upper end of rod N. is attached wire rope marked H. on Figs. 1. & 2..
This rope leads up and is fixed to small pulley K. which forms a portion or is.
connected with the segment or half circle G. (this is shown at F. Fig. 1). Round
segment G. is a wire rope, from one end of which hangs the bulkhead door B. the
other end of the rope being fastened to the segment. The thimble F. which is a
portion of or is fixed to segment G. and small pulley K. is slipped on, and is free
to revolve on a spindle U. Fig. 1. which is attached to bulkhead C. Fig. 1.
Thus with connections made between tank or float M. and bulkhead door B..
through the medium of wire ropes, and pulleys as herein before described, the
travel of the bulkhead door may be varied or increased, as compared with the
movement of the tank or float, to such an extent as may be required. To prevent
the door rattling in a sea way, I provide steadying guides marked J. and let into
grooves running the full length of the door as shown at Fig. 3.
P. Fig. 2. is a tube connected with the atmosphere so as to allow free movement
of the water, in water-tight casing L.
D. Figs. 1. & 2. is the framing fixed to the bulkhead, into which the door drops.
when shut.
E. Figs. 1. & 2. is a recess at the bottom of the framing, to prevent a lodgment
of dirt which prevents the door from getting properly into its seat.
S. Fig. 1. is a grating to prevent the non-return valves getting fouled.
T. Fig. 2. shows the connection between wire rope on segment G. and bulkhead
door.
R. Fig. 2. shows gland on the cover of water-tight casing L. for guiding
rod N.
The balance weight or float may be in the form of a tank, of any convenient
shape or any number of sections, or it may be of solid material of sufficient
buoyancy.
I do not confine myself to any particular form of non-return valves for allowing.
water to pass into the water-tight casing, or any particular kind of gear for making
the connections between the door and the larger pulley or lever, or between the
balance weight or float and the smaller pulley or lever.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1st. Pulley, or segment of a pulley or lever in conjunction with smaller pulley
or lever, as a medium by which bulkhead doors are balanced by a weight.
2nd. A water-tight casing with non-return valves, and containing balance weight
or float, as described and illustrated.
3rd. Steadying guides for preventing undue shaking of the bulkhead door, as,
shown at J. Figs. 2. and 3.

page_text: 4th. A bulkhead door connected to, and operated by a wire rope or other similar
gear attached to differential pulleys, segment of pulleys, or levers, and from thence
to balance weight or float, contained in water-tight casing, substantially as described
and illustrated.