Improvements in Fastening Devices for Divers' Helmets.
Year: 1889

page_text: Date of Application, 20th Aug., 1889
Complete Specification Left, 30th Apr., 1890-Accepted, 12th July, 1890
PROVISIONAL SPECIFICATION.
[Communicated from abroad by LA SOCIÉTÉ DES SPÉCIALITES MÉCANIQUES, of
48, Rue de Bondy, Paris, in the Republic of France.]
Improvements in Fastening Devices for Divers' Helmets.
I, ERNEST DE PASS, of 68 Fleet Street in the City of London, Fellow of the
Institute of Patent Agents, do hereby declare the nature of this invention to be as
follows:-
The present invention relates to improvements in the construction of divers'
helmets and consists essentially in a simple, secure and readily manipulated fastening
device.
The helmet itself terminates at its lower part below the collar in a smooth flange
of angular section sufficiently wide to bear on a considerable surface of the top
flange of the shoulder piece and on the indiarubber collar which forms the upper part
of the divers' dress, thus forming a tight joint. The contact which completes the
closing of the helmet is maintained in the following manner: A hook shaped piece or
catch is mounted in such a manner as to be capable of turning upon a pivot fixed to
a link which is itself capable of turning round a bearing carried preferably by the
front of the shoulder piece. At the back, the collar of the helmet is provided with a
projection passing through a stirrup or yoke pivotted to the collar of the shoulder
piece by a strong stud around which the stirrup or yoke turns. In placing the
helmet on the shoulder piece care must be taken to pass the said projection thereon
through the stirrup or yoke; in this position it will be readily understood that
it will be sufficient for the purpose of fixing the helmet to the shoulder piece
with the requisite security, to force together the collars or flanges at a point
diametrically opposite to the stirrup or yoke. This forcing together is the function
of the catch or hook, the requisite amount of pressure being secured in the
manner following: To the lower part of the catch or hook are fixed two handles
and by taking hold of these the catch or hook can be raised, causing it, thereby,
to turn upon the pivotted link in such a manner that the pallet or bent portion
of the catch or hook is caused to engage in a slight recess counter-sunk in
the upper part of the collar of the helmet; this being effected and care being
taken that the pallet does not become disengaged from the collar, the handles are
forcibly depressed and the india-rubber washer situated between the two collars or
flanges is compressed. The link turning about its fixed pivot draws after it the lower
part of the catch or hook where it is very firmly maintained by reason of the pivot
connecting the catch or hook with the link, having passed the dead point situated
vertically under the said stud which is a position of stable equilibrium for the link.
To prevent a shock or jerk moving the handles forward while the diver is at work
and thus opening the helmet, a spring bolt is provided under the catch or book which
when locked engages with the heel of said catch or hook and prevents it from being
opened by an accidental jerk. A milled head carried by the before mentioned spring
bolt has projecting from it a pin which in its locked position enters a recess in the
bearing of the spring bolt. When it is desired to disengage the catch or hook the
spring bolt is drawn down by means of its milled head thus withdrawing the pin
thereon from its recess, and by giving a slight turn to the milled head the said locking
pin is no longer able to enter its recess but bears against the outside of the bearing
and will thus be held out of action until it is again brought opposite to its recess.
Datal thin 30th dow of August 1889

page_text: COMPLETE SPECIFICATION.
Improvements in Fastening Devices for Divers' Helmets.
1, ERNEST DE PASS, of 78 Fleet Street, in the City of London, Fellow of the
Institute of Patent Agents, 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, reference being had to the accom-
panying drawings and to the letters and figures marked thereon, that is to say :-
This invention relates to improvements in the construction of divers helmets, and
consists essentially in a simple, secure and readily manipulated fastening device
whereby the screw or bayonet joints heretofore used may be dispensed with.
And in order that the invention may be readily understood, I proceed to describe
the same with reference to the accompanying drawings, in which
Fig. 1 shews a general arrangement of the helmet provided with the improved
fastening device.
Fig. 2 shews the fastening partly in section.
Fig. 3 also shews, partly in section, the hinge which is on the opposite side to the
fastening proper.
Figs. 4 and 5 shews, in full size, two views of the locking hook.
Figs. 6, 7 and 8 shew detail views of the link or, attachment for the locking hook.
Fig. 9 shews a detail view of the hinge; and
Figs. 10, 11 and 12 shew detail views of a safety bolt, the action of which will be
hereinafter explained.
The helmet proper 1, terminates, at its lower part, in a flange or collar 10 having
a sufficiently wide and smooth surface to clamp, for a sufficient width, the rubber
collar 5 which terminates the upper part of the divers dress, against the top 3, of the
shoulder piece 4, and to thus form a sound joint. The pressure which suffices to effect
the locking of the helmet is ensured in the following manner:-A hook 6, (see
figs. 1, 2, 4 and 5) is so mounted as to be able to turn about a pivot 7, fixed upon a
link 8, which can itself turn about a small axis 9, fixed invariably to the shoulder
piece 14, and at the front thereof. At the back, as shewn by the section Fig. 3, the
Hange or collar 10, of the helmet is provided with a tail piece 11, which passes through
a yoke or stirrup 12, pivotted to the collar 14, of the shoulder piece, by a strong
stud 13, around which the yoke or stirrup 12, is free to turn. When the helmet
has been placed upon the shoulder piece care must be taken to pass the tail piece 11,
into the yoke or stirrup 12. It will be readily understood that the helmet being thus
placed, it will be sufficient, in order to fix it with the requisite security, to press the
two collars 10 and 14 one against the other at the part diametrically opposite to the
yoke or stirrup 12. It is the function of the hook 6 to ensure this energetic locking
in the following manner :-The hook is taken hold of by the two handles 15 fixed
thereto at 16, and raised by causing it and the link 8 to turn about the axis 9 so that
the tooth or claw 17, of the hook takes into a slightly concave portion formed in
the upper part of the collar 10; this being done and care taken that the tooth or
claw 17, does not quit the collar 10, the handles are forcibly depressed, thus com-
pressing the rubber washer inserted between the two collars 10 and 14, and the link
turning about the fixed axis 9, takes with it the base of the hook which is very firmly
held in this position because the axis 7, by turning about the axis 9, has slightly
exceeded the vertical point corresponding to the axis 9, so as to take up a position of
stable equilibrium. The reaction of the rubber joint exerting itself through the hook 6
ensures the fixity of this position; fig. 2 shews the hook closed and fig. 2x shews it
open and ready to be closed.
To prevent shock or jerk acting upon the handles 15 while the diver is at work, and
so bringing forward the base of the hook and thereby opening the helmet, there is
arranged below this hook a spring bolt 18, which, when in its closed position, as in
Fig. 2, abuts against the heel of the hook 6 and prevents it from opening under the
action of an accidental blow. When it is desired to disengage the hook 6, the spring

page_text: bolt 18 is drawn down by means of its milled head 19 thus withdrawing the locking
pin 20 thereon from its recess, and by giving a slight turn to the milled head, the
said locking pin is brought to bear against the outside of the boss or bearing 21
(which serves as a receptacle for the spring) and is thus held out of action until it is
again brought opposite its recess, and allowed to enter therein.
Having now particularly described and ascertained the nature of this invention,
and in what manner the same is to be performed, I claim, as communicated to
me;
1. The improved hook fastening device for a diver's helmet, whereby tightness of
joint with the shoulder piece is ensured by a simple pressure substantially as described,
thus dispensing with the use of the present screw or bayonet joint fastenings.
2. The employment, in divers' helmets of the improved pressure fastening device
hereinbefore described, and shewn with reference to the accompanying drawings.
3. The special arrangement of fastening device hereinbefore described and shewn
and for the purpose set forth.