Improvements in Means or Apparatus for Lifting and Lowering Watertight Doors of Bulkheads on Board Ship.
Year: 1890

page_text: Date of Application, 28th Mar., 1890
Complete Specification Left, 29th Dec., 1890-Accepted, 31st Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in Means or Apparatus for Lifting and Lowering
Watertight Doors of Bulkheads on Board Ship.
I, WILLEM Frederik Daniel VAN OLLEFEN, Ship and Engineer Surveyor
to Lloyd's Register of British and Foreign Shipping, of 35 Hoogte Kadijk,
Amsterdam, in the Kingdom of Holland, do hereby declare the nature of my
invention to be as follows:-
The watertight door and its framing are constructed and fitted in any ordinary
or suitable manner to enable my invention to be applied thereto.
My improved lifting and lowering apparatus is placed above the door in any
convenient position, and is constructed and operates substantially in the following
manner.
I mount a shaft or spindle in suitable bearings fixed to the watertight bulkhead;
on this shaft or spindle is fixed a wheel which by suitable gearing is capable of
giving motion to the watertight door. On this shaft or spindle is mounted a brake
pulley which is loose thereon and which will allow the shaft or spindle to revolve
without carrying the brake pulley along with it.
To the brake pulley is attached a pawl and pawl spring.
The brake pulley can be held stationary by means of a brake band encircling
the same and this brake band can be tightened or loosened by means of a screw and
nut wheel held by a bracket fastened to the bulkhead or by a bracket held by the
framing of the apparatus itself, a ratchet wheel is securely fastened to the above-
mentioned shaft or spindle.
One end of the said shaft or spindle is of appropriate form to receive a suitable
key to rotate the same.
To explain the working of it, I will suppose the door to be down (shut) and the
brake band to be slackened.
To lift the door the brake band is first tightened by means of the screw and the
nut wheel; this makes the brake pulley stationary as long as the brake band is
kept tight, and as the pawl and pawl spring are attached to the brake pulley the
pawl and spring remain also stationary; a key or other suitable appliance is placed
on the end of the shaft or spindle appropriate for this purpose and the spindle is
rotated in the required direction.
The consequence is that the door is raised as the motion of the shaft or spindle is
imparted by means of suitable gearing to the door itself. The ratchet wheel (being
fixed to the shaft or spindle) will rotate with the shaft or spindle past the brake
pulley, which is pro tem. as above explained a fixture. The pawl will click against
each tooth of the ratchet wheel and thereby keep the door at the height to which
it is raised. This action is carried on until the door is fully open; it will be
evident that the weight of the door is then entirely held up by the friction of the
brake band on the brake pulley (or sheave).
The weight of the door pulls then on the shaft or spindle in the direction for
closing the door, and on account of that the ratchet wheel will bear against the
pawl, which however is held by the brake pulley and this latter is held in its turn
by the brake band; by these means all that is required to lower the door is to ease
the brake band.
It will be clear that when the brake band is eased gently, the door will close
gently; if the brake band is released at once, the door will drop at once.
The advantages of this arrangement are:-
1st. The door cannot be opened when the lowering gear is not fit to work. The
door is then safe for the ship.

page_text: 2nd. The time required to close the door is very much shorter than with any
of the arrangements known to me, being a matter of seconds only instead of
minutes.
3rd. All the parts are always accessible, simple in their construction and not
liable to get out of order.
4th. Should any accident befall the working parts, the door will close itself by
its own weight and be safe for the ship.
5th. The manipulation of the apparatus is so simple that any person either skilled
or unskilled, or even a child can readily lower the door.
6th. Nothing can be mislaid or wanting at the moment when the door is to be
closed, when the vessel meets with accident and the crew is panic striken.
7th. If the door does not close by its own weight on account of something being
under it, the closing of the door can be assisted by means of the same key or
appliance that is used to raise the door.
8th. In case of fire on board it is probable that the brake band will expand by
the heat so much as to release its grip, the door will then fall and be safe for
the ship.
Dated March 28th 1890
VILLEM FREDERIK DANIEL VAN OLLEFEN.
By Harris & Mills,
23, Southampton Buildings, London, Agents.
COMPLETE
SPECIFICATION.
Improvements in Means or Apparatus for Lifting and Lowering
Watertight Doors of Bulkheads on Board Ship.
I WILLEM FREDERIK DANIEL VAN OLLEFEN, Ship and Engineer Surveyor
to Lloyd's Register of British and Foreign Shipping, of 35 Hoogte Kadijk,
Amsterdam, in the Kingdom of Holland, 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 :-
My invention has for its object to provide simple and effective means whereby
water-tight doors of bulkheads on board ship may be readily opened and either
rapidly or gradually closed as desired.
The water-tight door, and its framing, may be constructed and fitted in any
ordinary, or suitable, manner to enable my invention to be applied thereto.
My improved raising and lowering apparatus is arranged and secured in any
convenient and suitable position above the door and consists of a shaft or spindle
mounted in bearings which may be fixed to the water-tight bulkhead and is capable
of raising and lowering the door. This may be effected by means of a pinion fixed
to the shaft or spindle engaging in a rack fixed to the door. The rotation of this
spindle is governed by friction gear of any suitable construction preferably con-
sisting of a brake pulley (loosely mounted on the shaft or spindle) and a friction
band or strap which can be caused to grip the said brake pulley so as to allow the
shaft or spindle to revolve without carrying the brake pulley round with it.
To the brake pulley is attached a spring pawl to engage the teeth of a ratchet
wheel fast on the shaft or spindle the teeth of which wheel are so arranged that in
raising the door the wheel will run over the pawl but the pawl will not allow the
wheel to run over it in the direction for lowering the door.
The friction strap or band can be caused to grip the brake pulley more or less
tightly as required by means of a screw to which one end of the band is secured and
nut wheel held by a bracket fastened to the bulkhead or by a bracket held by the
framing of the apparatus itself to which bracket the other end of the band is secured.
One end of the said shaft or spindle is of appropriate form to receive a suitable
key or handle by which the spindle can be rotated.
When the door is to be raised the friction band or strap is preferably first tightened

page_text: on the brake pulley by means of the screw and nut wheel and then the spindle is
rotated in the required direction to raise the door. As the brake pulley is held
stationary by the friction band the ratchet wheel as the door is being raised will
slip past the spring pawl on the brake pulley and when the door is raised to the
desired height it will be retained in this position by the engagement of the pawl
with the teeth of the ratchet wheel, the door being sustained by the frictional
contact of the brake band on the brake pulley.
The weight of the door then tends to rotate the shaft or spindle in the direction
for closing the door it is therefore evident that to lower the door all that is required
is to ease the brake band.
When the brake band is eased gently the door will close gently but if the brake
band be released suddenly the door will close at once. It will be evident that any
suitable frictional device may be employed in place of the brake pulley and band
described but the arrangement described is I believe the best for the purpose. It
will further be evident that the pawl and ratchet wheel may be reversed the pawl
being then on a part connected to the shaft and the ratchet wheel being secured to or
formed on the brake pulley and further that any suitable gear may be used for
causing the rotation of the shaft or spindle to raise and lower the door and also that
the several constituent parts may be reversed and shifted to best suit the available
space on board the ship.
And in order that my said invention may be fully understood I shall now proceed
more particularly to describe the same and for that purpose shall refer to the
several figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawing represents in front elevation a bulkhead
door raising and lowering device constructed according to my invention
A is a
frame or bracket secured by bolts a to the bulkhead above the bulkhead door.
Mounted in bearings in the frame or bracket A is a spindle B on which is fixed a
pinion C which gears with a rack D secured to and projecting upwards from
the door. Loosely mounted on the spindle B is a pulley E carrying a spring pawl F
for engaging the teeth of a ratchet wheel G fast on the spindle B. Around the
pulley E is a brake band H one end of which is secured to the bracket A at the
other end being connected to a screw e passing through a hole in a lug or projection d
on the bracket A. On end of the screw c projecting above the lug is screwed a
wheel nut e which bears on the upper end of the lug d. By turning this wheel nut
in one direction or the other the frictional contact of the band on pulley E may be
regulated as required.
When the door is to be raised the wheel nut e is operated so that the band H
is caused to grip the pulley E and then by means of the key or handle the
spindle B is turned in the direction indicated by the arrow, and the door raised
to any desired height by reason of the pinion C gearing with the rack D. The
pulley E being prevented, by the frictional contact therewith of the band H,
from rotating the teeth of the ratchet wheel G which is fast on the spindle,
will slip over the pawl F. When the door is raised to the extent required its
weight tends to turn the spindle B in the direction to close the door (that is in the
reverse direction to that indicated by the arrow) causing one of the teeth of the
ratchet wheel G to bear on the pawl F and thereby tend to force the pulley E
round with the spindle which however it cannot do by reason of the frictional contact
therewith of the band H which thus retains the door in the position to which it has
been raised. To admit of the door closing, the band H is slackened by means of
the wheel nut e so as to allow the pulley E to turn with the spindle B. If the door.
be required to be closed rapidly the frictional contact of the band is entirely removed
from the pulley E whereupon the door will rapidly descend by its own gravity
inrestrained, but if the door is to be closed gradually the speed of the descent
can be governed by means of the wheel nut e so as to retard its descent as
equired.
X is a key or bolt which I have shewn as passing through a hole in the bracket and

page_text: with its end projecting so that in the event of any accidental loosening of the brake
this key or bolt will prevent the door from falling until the key or bolt is
removed.
In the arrangement according to my invention all the parts are always accessible
and they are simple in construction and not liable to get out of order, and the door
can be closed very rapidly when required whilst should any accident befall the
working parts the door will close by its own weight. In case of fire in proximity
to the apparatus the brake band will expand by the heat so as to release its grip on
the wheel E and the door will close at once.
In Figure 2 I have shewn a modified form of frictional device or brake wherein
the brake block H2 is used to bear on the wheel the said block being knuckle jointed
to the frame A at and pressed into contact with the wheel E as required by the
screw c² working in the bracket and operated by the band wheel e².
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. In apparatus for opening and closing watertight doors of bulkheads, a
frictional device by means of which the door can be retained open when raised to
any desired extent and whereby the closing of the door can be effected rapidly or
gradually as required substantially as hereinbefore described.
2nd. In apparatus for opening and closing watertight doors of bulkheads the
combination with the raising and lowering mechanism, of a brake pulley and friction
band or equivalent frictional device for retaining the door in the position to which
it is opened and for governing the speed with which the door closes substantially as
hereinbefore described with reference to the accompanying drawings.
3rd. The combination with means for opening and closing watertight doors of
bulkheads, of the spindle B, brake pulley E friction band H ratchet wheel G pawl F
and means for increasing and reducing as required the friction of the band on the
pulley the whole being arranged to operate substantially as and for the purpose
hereinbefore described and illustrated in the accompanying drawings.
4th. The arrangement and combination of parts constituting the apparatus as
hereinbefore described and shewn in the accompanying drawings for the purposes
described.
Dated this 29th day of December 1890.
J. H. JOHNSON & CO.,
Agents.