Improvements in Bolt Fastenings for Box-lids, Doors, and the like.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Bolt Fastenings for Box-lids, Doors, and the like.
WILLIAM JOHN MARCHANT, 13, Oakland Road, West Jesmond, Newcastle-on-
Tyne, Marine Engineer and Draughtsman, do hereby declare the nature of this
invention to be as follows:-
A bolt which swings on a pin passing through two lugs, cast or fixed on any
side of a box, or the like. The bottom end of the bolt is shaped like a cam,
with the upper edge hollowed out. The upper part may be of round or square
section. The upper part passes through a slot in the overlapping edge of a
door, lid, cover, or the like, and is fastened by means of a cotter inserted therein
or a screw thereon. When the upper part of the bolt is knocked, or pressed
back, the cam, turning on pin referred to, lifts the lid, door, cover, or the like.
It is specially adapted for mud-boxes, such as are used in ships, mines, and the
like, where expedition in fastening and unfastening the lids, covers, doors, or
the like is of importance.
Dated this day of June 22nd 1899
WILLIAM JOHN MARCHANT.
Improvements in Bolt Fastenings for Box-lids, Doors, and the like.
I, WILLIAM JOHN MARCHANT, of 13, Oakland Road, West Jesmond, Newcastle-
on-Tyne, Engineer and Draughtsman, 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:-
Figure 1 is a side view of an improved square or round section cam lever bolt
according to my invention. The bolt A, B, is so made as to be capable of partial
revolution on a pin C passing through two lugs cast or otherwise fixed on the
side of a box or the like, and the effect of this partial revolution is to cause the
point of the cam F to move along the path of the dotted line FH; the point D
acting as a heel and preventing the bolt from revolving further.
Figure 3 represents part of a mud box with one of my cam lever bolts shewn
in position. The same lettering is used for the same parts in both figures.
The path of the cam point F on the partial revolution of the bolt A B on the
centre C being again shewn by the dotted line F H. G is the cover of the mud
box and it will be seen that before the point of the cam F reaches the position H
the cover of the box must lift, also that it is lifted by a force corresponding to
the leverage due to the difference of length of shank of the bolt and its cam
which may be any convenient ratio. On closing the lid or cover, the reverse
D

page_text: process is accomplished, that is to say the point of the cam F being forced along
the dotted line H F, the bolt A, B, assumes an upright position, when the stop X
prevents the lid from springing open again. The same being finally secured
by the insertion of a cotter at K.
Figure 2 is a side view of one of my cam lever bolts made however in round
section instead of square as in Figs. 1 & 3, and made also double, so that in the
event of the point of the cam F being broken or much worn away, the bolt A, B,
may be turned round. In this case a nut, which may be flanged or otherwise,
takes the place of the cotter and the stop X as in Figure 1.
The object of my invention is to effect the removal of the covers of mud boxes
and the like and access to the interior with greatly increased facility as compared
with the present arrangement. That is to say, when such a cover has been some
time in position it is usual to find that it is adherent to the box with great
tenacity from the adhesion to both cover and box of the packing which is
employed to make the joint air tight; and it is usual to insert a cold chisel
between the cover and the box & then by hammering this chisel to force the
cover and box asunder. This is attended with some risk of breaking the cover
and it is often attended with great inconvenience from the confined and
inaccessible situation in which mud boxes require sometimes to be placed.
My invention while well adapted for use on mud boxes on board ship, is
specially so for bulkheads & watertight doors such as are used on board ship.
when expedition & facility in fastening & unfastening air or water tight joints
is desirable.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
The improved cam lever bolt for securing the doors of mud boxes and other
air or water tight alleyway doors substantially as described.
Dated this Seventeenth day of March 1900.
WILLIAM JOHN MARCHANT.