Improvements in Mechanism for Moving Doors or Valves, such as the Water-tight Doors of Ships' Bulkheads
Year: 1886

page_text: Date of Application, 15th Mar., 1886
Complete Left, 14th Dec., 1886.
Complete Accepted, 28th Jan., 1887.
Improvements in Mechanism for Moving Doors or Valves, such as
the Water-tight Doors of Ships' Bulkheads.
I, JAMES ANGELO MCELROY, of 3 Edward Street, Overnewton, Glasgow, in the
County of Lanark, North Britain, Engineer, do hereby delare the nature of this
Invention to be as follows, that is to say:-
My said Invention has for its object to apply improved mechanism to any doors or
valves which like the water-tight doors of ships' bulkheads may on an emergency or
for any purpose be required to be capable of being closed with rapidity and certainty.
In carrying out my Invention in the case of a door for a ships bulkhead I use the
vertical screw spindle commonly employed for opening and closing such doors; but
instead of having it working in an internally-screwed block or nut fixed to the door,
I have in gear with it two wormwheels, one on each side of it these wormwheels being
on spindles held in bearings in a casting or fitting fixed to the door. When the worm-
wheels are prevented from turning the parts of them in contact with the screw spindle
act as a fixed nut, and the door can be moved up or down by turning the spindle in the
ordinary way. In the event of its being required to close the door rapidly the worm-
wheels are released and then they are free to roll down along the screw spindle as the
door descends by its own weight.
I prefer to arrange the wormwheels and parts in connection with them so that the
descent of the door may be controlled; and for this purpose I form screw threads on
parts of the wormwheel spindles and I provide a cover or plate with internally screwed
holes for the screwed parts of the spindles to work in. In one modification the cover
or plate is held by a short lever or cam in such a position that the wormwheel spindles
cannot turn in it so that the wormwheels are then as parts of a fixed nut. When the
lever or cam is turned so as to release the cover or plate then the wormwheels can
turn, and in doing so by their serewing action move the plate so as to compress a spring

page_text: or springs. As the springs offer increased resistance in proportion as they become
compressed, they counteract the tendency of the door to acquire a too rapid rate in
descending. In another modification a cam of a special form is used, and an anti-
friction roller may be fitted to the cover or plate for the cam to act on. This cam is
shaped with a gradual curve and allows the plate or cover to move only in proportion
as the cam is turned, so that the rate and extent of the descent of the door depends on
the quickness and extent of turning movement given to the cam.
The lever or cam is turned by means of a square spindle up and down which it
moves with the movement of the door, and which is held in bearings in brackets fixed
to the bulkhead. The square spindle has one or more handles fixed on it, and may be
connected in any convenient way to handles at a greater or less distance; a locking
catch being provided to prevent the parts from getting accidentally into a position to
allow the door to close when not required.
The parts may be transposed, the screw spindle being arranged to move with the
door whilst the wormwheels are upon a stationary bracket.

page_text: Improvements in Mechanism for Moving Doors or Valves, such as
the Water-tight Doors of Ships' Bulkheads.
I, JAMES ANGELO MCELROY, of 3 Edward Street, Overnewton, Glasgow, in the
County of Lanark, North Britain, 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, that is to say:
My said Invention has for its object to apply improved mechanism to any doors or
valves which like the water-tight doors of ships' bulkheads may on an emergency or
for any purpose be required to be capable of being closed with rapidity and certainty.
In carrying out my Invention in the case of a door for a ships' bulkhead I use the
vertical screw spindle commonly employed for opening and closing such doors; but
instead of having it working in an internally-screwed block or nut fixed to the door, I'
have in gear with it two worm wheels, one on each side of it, and which when prevented
from turning act like parts of a fixed nut so that the door can be moved up or down
by turning the screw spindle in the ordinary way. In the event of its being required
to close the door rapidly the wormwheels are released and then they can roll down
along the screw spindle as the door descends by its own weight, I prefer to arrange
the wornwheels and parts in connection with them so that the descent of the door may
be controlled; and for this purpose. I use mechanism which is hereinafter described.
And in order that my said Invention and the manner of performing the same may
be properly understood I hereunto append a sheet of explanatory drawings to be
hereinafter referred to and representing the application of my improvements to a
ship's-bulkhead door.
Figure, 1, is a sectional elevation, figure, 2, is a horizontal section, figure, 3, is a
side view of a detail, and figure, 4, is a vertical section as at right angles to figure, 1.
In these drawings the same reference numerals are used to mark the same or like parts
wherever they are repeated.
•
The door shown in the drawings consists of a plate, 5, having fixed on its outer
surface a frame formed with top and bottom bars, 6, 7, and with side bars, 8, which last
are made with tapered or wedge-shaped flanges or ribs. The opening or doorway, 9,
in the bulkhead, 10, has fixed round its edge a rectangular frame, 11, which is planed
and finished on its outer surface; and a brass strip is fixed on the inner surface of the
door, 5, to bear upon the door-way frame, 11, when the door is closed. The sides
of the door-way frame, 11, are formed with projecting flanges or ribs, which with
covering plates, 12, (one of which is supposed to be removed in figure, 1,) form guides
for the side bars, S, of the door, 5, and being tapered or wedge-shaped like the side
bars, 8, cause the door to be pressed tightly against the door-way frame, 11, when
forced down to the bottom of the guides.
To the upper part of the door, 5, there is fixed a hollow or box-like casting, 13,
in which are held in suitable bearings two wormwheels, 14, fixed on spindles, 15,
which project through the outer side of the casting, 13. Between and gearing.

page_text: with the two wormwheels, 14, there is a vertical screw spindle, or shaft, 16, corre-
sponding to the one commonly employed for opening and closing bulkhead doors,
and when the wormwheels, 14, are prevented from turning the paris of them in
contact with the screw shaft, 16, act like parts of a nut and the door can be raised
or lowered by turning the screw shaft in the ordinary way. The arrangements
for turning the screw shaft, 16, may be various; it is however shown as having its
upper end held in a bearing in a bracket, 17, bolted to the bulkhead, 10, and as having
fixed on it a spurwheel, 18, gearing with a spurwheel, 19, on a short vertical shaft, 20,
also carried by the bracket, 17. This shaft, 20, has also on it a bevil wheel, 21,
gearing with a bevil wheel which is not shown but which is carried on a stud, 22, fixed
to the bracket, 17, the bevil wheel being fixed to a pulley (not shown) which is also
carried on the stud, 22, and which has passing round it a rope or chain. The screw
shaft, 16, can be turned by means of the gearing and the rope or chain referred to, or
it can be turned from above the deck, 23, the upper end of the shaft, 20, being
extended up into a metal box, 24, fitted in an opening made through the deck.
cover, 25, is fitted to the box, 24, and when this cover is removed a turnkey or handle
can be applied to the shaft, 20, the upper end of which is squared for the purpose..
A
The worm wheels, 14, which engage with the screw shaft, 16, are prevented from turning
in ordinary circumstances by means of their spindles, 15, these spindles being formed
with screw threads which work in internally screwed blocks or nuts, 26, held by a
cover. plate or bar, 27, and confined by nuts screwed on the ends of the spindles, 15.
The screw threads on the spindles, 15, are such as to draw in the cover bar, 27, when
the wormwheels turn in the directions due to their rolling down the screw shaft, 16,
as down a rack;. but this drawing-in action is prevented in ordinary circumstances by
a.short lever, 28, fitted with an antifriction roller and bearing on a curved surface
formed on the inner side of the cover bar, 27. This short lever, 28, is formed on an
elongated tubular boss, 29, held vertically in bearings on the box casting, 13, fixed to
the door, 5, the passage through this boss being square to fit and slide on a vertical square
shaft, 30, having a footstep bearing in a rail or frame piece, 31, fixed by its ends to the
door-way frame, 11, and extending up through a bearing in the bracket, 17, and into
a box casting, 32, fixed in an opening in the deck, 23. The square shaft, 30, can. be
turned by means of a hand lever, 43, fixed on its lower end, or by means of a turnkey or
handle applied from above the deck, 23, to its upper end after removing the cover of
the box casting, 32. The lower part of this box casting, 32, is made like a clutch, and a
clutch piece, 33, fitted on the shaft, 30, engages with it, this clutch, piece being made with
collars between which a forked lever, 34, engages. The outer end of the lever, 34, has
jointed to it a rod, 35, extending down to the top of the door way and connected to a
fixed point by a small weighted lever or radius link, 36. The weights of the parts.
are such that when left to themselves they lift up the clutch piece, 33, so as to engage
with the bottom of the box casting, 32, and thereby prevent the square shaft, 30, from
being turned accidentally. The rod, 35, passes through a fixed plate, 37, and has a
nut screwed on its bottom end to retain it; and it is formed with a hook, 38 to retain
the end of the hand lever, 43.
If the door is to be set free from the deck, a suitable turnkey is applied to the upper
end of the square shaft, 30; and is first depressed so as to push down the clutch
piece, 33, and clear it from the bottom of the box casting, 32, this movenient also
acting through the lever, 34, and rod, 35, to set free the hand lever, 43, below. The
square shaft, 30, is then turned and turns the short lever, 28, so as to allow the cover
bar, 27, to move inwards. The wormwheels, 14, can then turn and the door, 5,
descends by its weight, the wormnwheels rolling down the sides of the screw shaft, 16.
The descent is however controlled and prevented from becoming too rapid by helical
springs, 39, placed on the wormwheel spindles, 15, and which are compressed by the
drawing in of the cover bar, 27. The descent can also be controlled and even stopped
at any point by means of the square shaft, 30, and by retarding or limiting the
movement of this, shaft. The part of the cover bar, 27, acted on by the small lever, 28,
is curved so that the extent to which the bar can move inwards is proportional to the

page_text: angle through which the lever, 28, is turned. If the lever, 28, is moved to its full
extent the door can descend until it completely closes the doorway, but if the lever, 28,
is moved only partly over the door will be stopped in a corresponding position. If the
door is to be set free from below the rod, 35, is first pushed up, this movement releasing
the hand lever, 43, and also moving down the clutch piece, 33, clear of the box
casting, 32, at the deck, and the hand lever, 43, can then be turned as much as may be
required. On the upper end of the tubular boss, 29, which is held in bearings on the
casting, 13, fixed to the top of the door, and which has the square shaft, 30, passing
through it, there is fixed a segmental block, 40, having its outer part shaped to fit upon
one or two of the threads of the screw shaft, 16, and the square shaft, 30, can be turned
sufficiently far round to bring the block, 40, into, contact with the screw shaft, 16.
The block, 40, will then act as part of a nut to the screw shaft, 16, and by turning this
shaft the door can be raised or lowered independently of the wormwheels, 14, if at any
time required.
The parts of my improved apparatus may be transposed by fixing the screw shaft, 16,
to the door and arranging the wormwheels, 14, and accessory parts on a stationary
bracket or framing,
Having now particularly described and ascertained the nature of my said Invention
and in what maner the same is to be performed I declare that what I claim is :
1.
The arranging or combining together the parts of mechanism for moving doors
or valves such as the water-tight doors of ships bulkheads substantially in the improved
manner hereinbefore described and as shown on the accompanying drawings.
2-In mechanism for moving doors or valves, the combination of a screw shaft with
a pair of wormwheels, the wormwheels acting as a nut to the screw shaft when they
are prevented from turning, birt capable of rolling along the screw shaft when set free
to turn, substantially as hereinbefore described.
EDMUND HUNT,
Applicant's Agent.