IMPROVEMENTS IN SELF LEVELING BERTHS
Year: 1883

page_text: LETTERS PATENT to Benjamin Franklin Merrill of Boston in the County of
Suffolk and State of Massachusetts in the United States of America for an
COMPLETE SPECIFICATION filed by the said Benjamin Franklin Merrill
at the Office of the Commissioners of Patents on the 11th September 1883.
BENJAMIN FRANKLIN MERRILL of Boston in the County of Suffolk and State
of Massachusetts in the United States of America IMPROVEMENTS IN SELF
LEVELING BERTHS
In the accompanying drawings forming a part of this specification, Figure 1 is
a perspective view of a berth embodying my invention one end of which is not
shown and a portion of the front side being shown as broken away to give a
more clear view of the details of construction. Figure 2 is a vertical cross section,
and shows in end elevation a portion of my improvements as they are when the
berth is level and the vessel upright. Figure 3 is a similar view showing the
berth level while the vessel is represented as rolling and the bulk head consequently
inclined. Figure 4 is a central longitudinal section of the suspended berth and
its removable bed support or bottom with one end omitted from the view.
Figure 5 is a top view or plan of the same. This berth is designed to be placed
lengthwise of the ship and its self leveling mechanism is arranged to keep it
horizontal when the ship rolls. If placed athwart ship, the same mechanism
tends to keep it unaffected by the pitch of the ship. In the figures A represents
the frame of a berth embodying my invention. B is the removable bed bottom,
supported in said frame and upon which the bedding rests, C is the end of the
berth frame. K is the bulk head. On the bulk head is a stud e about which is
guided a yoke E by means of a slot f formed therein. To the lower extremity of
the yoke is secured a weight L. The end of the berth frame C is secured to the
ends of the arched portion of the yoke E by links D pivoted to said yoke at c¹
and to end C at c. There is also secured to the bulk head K, a metallic rack F
firmly bolted thereto and upon the end C of the berth frame there is formed or
[Price &

page_text: „
attached a toothed segment or curved rack I which gears with the co-acting
rack F as shown. The rack F sustains the weight of the berth, the links D, the
yoke E and weight L; the stud e serving as a pivot about which the yoke E. may
oscillate and at the same time have a slightly vertical play. As represented in
the drawings, the teeth of the co-acting racks * bottom a mechanical i
disadvantage which may be obviated by forming flanges upon the sides of said
racks F and I which shall come in contact before the ends of the interlocked teeth
come to a bearing. These flanges will then sustain the weight of the berth and
its leveling mechanism. The co-acting racks F and I prevent the teeth having
any independent lateral vibration irrespective of the roll of the vessel and while
leaving the berth perfectly free to assume and maintain at all times a laterally
horizontal or. level position, it is as stated, thereby held from lateral vibration
when the bulkhead and berth change their relative positions by reason of the
rolling of the vessel. When the vessel rolls as represented in figure 3 the action
of gravity on the weight L suspended on the vertical arm of the yoke E exerts
sufficient force upon the berth through the links D to maintain the berth in a
horizontal position. The aforesaid devices are preferably constructed of metal so
that they may be strong and yet occupy the minimum of space
A headboard is intended to be fastened to the berth parallel to the end C
between which and the said end the pendent arm of yoke E may swing. This
headboard is omitted from the drawings to afford a clearer view of the operative
devices The rack F may be formed as shown, or it may be curved and the
co-acting rack I may be made straight, or the requisite curvature may be divided
between them, giving to the toothed portion of each a curved periphery but
however respectively shaped they must be of such form and be so relatively
placed as to sustain the weight of the berth and the leveling mechanism and
remain in gear, in whatever position the vessel may assume. The berth instead
of being supported by the rack I on the rack F might be fixed to an axle working
in a bearing in the bulkhead so that when the ship rolls and the berth oscillates
under the action of the self leveling mechanism, the point of support of the end
of the berth shall be stationary and vertically over the longitudinal axis of figure
of the berth on which the weight of the berth and its occupant may be assumed
to be concentrated. The support given by co-acting racks or their equivalent is
however preferable both on account of the extended surface of support afforded
(which is secured with a minimum of friction) and also by reason of the
advantage gained by having the point of support shift relatively to the line in
which the weight of the berth and its occupant acts.
When the ship is on an even keel, the berth having its occupant lying therein is
horizontal. The weight of the berth and its occupant tends to hold the berth in
that position, the weight being vertically below the point of contact of the co-acting
racks, When the ship is rolled towards the star board, the action of gravity
causes the pendent arm and weight of yoke E to make an oscillation also toward
the star board, and thereby the berth is turned toward the port. The momentum
acquired by the pendent arm of the yoke however tends to carry it beyond the
point where it would come to rest, under the action of gravity, and consequently to
turn the berth slightly too far to the port, but the point of contact of the co-acting
racks having been simultaneously moved toward the port, the weight of the berth
and its occupant acts in a vertical line to the starboard of the point of contact of
the co-acting racks and tends to counteract the effect of the momentum of the
pendent arm of the yoke so that the pendulum is quickly and without jar brought
to a vertical position immediately after each oscillation. The other end of the
berth is constructed and supported in the same manner as described for the end
shown in the drawings though one pendulum and links as shown may suffice.
By a proper relative arrangement of the points, c'e e¹ the axis of oscillation e and
the racks F and 1 there will be little or no vertical motion of the yoke upon the
stud When the berth is turned independently of the rolling of the ship as for
example by a person climbing in or by a change in the position of the occupant

page_text: the yoke E is caused to swing from its vertical position. It then acts not only as
a pendulum, but also by reason of the free vertical motion permitted by the slot f
as a dead weight, tending to counteract the disturbing force and restore the berth
to its horizontal position. The weight L on the pendent arm of yoke E shifts
laterally as the berth is turned and acts through the links D to right the berth
with a leverage increasing with the amplitude of the arc through which the berth
is turned.
What I claim is -1 A ship berth supported at each end upon co-acting racks F
and I, the one attached to the berth and the other to the bulk head in combination
with a pendulum guided vertically upon a stud attached to the bulk head and
oscillating upon the same about an axis parallel to the longitudinal axis of the
berth and connected to the end of the berth by links whereby the motion of the
pendulum under the action of gravity is communicated to the berth so that the
berth shall assume a horizontal position when the pendulum is vertical substantially
as shown and described.
2 A ship berth to one end of which is connected a pendulum free to move
vertically upon a stud attached to the bulk head and to oscillate upon the same
about an axis parallel to the longitudinal axis of the berth and connected to an
end of the berth by links in combination with co-acting racks or their equivalent,
as supports for the ends of the berth whereby the weight of the berth and its
occupant acts to oppose the momentum of the pendulum when a transverse
oscillation is imparted to the berth substantially as shown and described. 3rd In
combination with a ship berth supported on bearings at its ends and capable of
transverse oscillation thereon, the weighted yoke E pivoted to the bulkhead so as
to have a free vertical movement on its pivot e as shown and described, and
connecting links I) whereby when the berth is turned from a horizontal position,
the yoke E acts through the links D as a shifting weight to restore the berth to a
horizontal position substantially as shown and described. 4th In combination with
a ships berth, the weighted yoke capable of vertical movement on the pivotal stud
attached to the bulkhead, the links connecting the yoke with the end of the berth
the supports for berth and adjusting devices consisting of bearing pieces on
the ends of the berth and on the bulkhead, respectively having one of their
corresponding bearing surfaces segmental or curved and the other straight, and
means for preventing the sliding or shifting of one bearing surface longitudinally
upon the other whereby the berth will be kept in a horizontal position and the
weight of the berth and its occupant acts to oppose the momentum of the pendulum
when the vessel rolls all substantially as shown and described
In witness whereof I the said Benjamin Franklin Merrill have hereunto set
my hand and seal this first day of September in the year of Our Lord, One
thousand Eight hundred and Eighty three
DENTAMIN TD ALETTA MED DILL
DENTAMIN D ANTIN WERDILL
CHRICAT
(L.S.)