Improvements in Rope, Cable, and Chain Grips.
Year: 1896

page_text: Date of Application, 5th Mar., 1896-Accepted, 11th Apr., 1896
.
COMPLETE SPECIFICATION.
Improvements in Rope, Cable, and Chain Grips.
We, WILLIAM SANDERSON DAWSON, of 45 Hendon Road, Sunderland, in the
County of Durham, Rope Maker, and DAVID DISHART, of 11 Pemberton Street,
Sunderland, aforesaid, 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 :-
Our invention relates to apparatus for securing or holding ropes, cables, chains,
or similar articles for mooring, haulage, or other purposes, and the main object of
our invention is to effect the combination, in an improved manner, of an elastic
resistance with the rope holding apparatus, so that sudden or extra strains upon
the rope will be absorbed without injury to the rope, or the said holding
apparatus.
In apparatus of this class, as ordinarily constructed without an elastic resistance,
sudden or violent strains on the rope frequently result in breakage of the rope, or
of the apparatus, or in tearing the said apparatus from its attachments, and as
such strains are unavoidable and of constant occurrence, an arrangement which will
effectually absorb them without injury is of great value.
In the accompanying sheet of drawings, which forms part of this Specification
and illustrates an apparatus constructed in accordance with our invention;
Fig. 1 is a plan;
Fig. 2 is a longitudinal sectional elevation, through A A in Fig. 1;
Fig. 3 is a cross-sectional elevation through B B in Figs. 1 and 2;
Fig. 4 is a plan of a special form of washer used with the apparatus;
Fig. 5 is a longitudinal sectional elevation, and
Fig. 6 is a cross-sectional elevation of the movable gripping jaw, shewing a
particular device combined therewith.
Similar letters of reference denote similar parts throughout the drawings.
. A rectangular frame, consisting of two sides C, C, and two ends C, C', is
provided to receive the various parts of the apparatus. This frame may be open
as shewn, or, if desired; may be formed with a closed bottom. It may be cast or
forged in one piece, or in halves as shewn, the division being on the centre line A A,
Fig. 1. Lugs D are provided on the ends C, to receive bolts E, which unite the
halves of the frame together, and lugs F are provided on the sides C, with apertures
to receive bolts, or other devices for the attachment of the apparatus to a vessel's,
deck or elsewhere, as required.
The sides C C are formed with V-grooves C2, as shewn most clearly in Fig: 3.
The said grooves are parallel to each other, and form ways in which a bed
plate H can slide, the said bed plate having V shaped edges to fit the said
grooves C2.
J is a jaw, hinged at one end by means of the pin or bolt K, between the
cheeks L L on the bed plate H.
B
A channel M is formed in the bed plate, and the rope, cable or chain N, to be
secured, is laid in such channel. A similar channel M' is formed on the underside
of the jaw J, to bear on the top of the rope, and the necessary pressure to secure
the rope is given by means of a screw P, hinged by its T shaped end P1, in an
aperture P2 in the bed plate, and provided with a nut Q, which bears on the outer
end of the jaw J, the said outer end being forked, as shewn clearly in Fig. 1, to
receive the screw P.
The nut has arms Q', made in one piece therewith, or attached thereto, to
.

page_text: give the required leverage. When the nut-Q is slackened, the screw P can be
brought forward clear of the jaw J, and the said jaw can then be thrown back,
to allow a rope to be laid in, or removed from the channel M.
.
Such positions of the said screw and jaw are shewn,by dotted lines in Fig. 3.
A washer R is provided under the nut Q, formed with three or more inwardly
projecting lugs R₁ on the edge of its upper side, engaging with a suitably shaped
annular groove Q on the nut. This arrangement prevents the washer falling
away from the nut when the latter is slackened, while at the same time it
permits the nut to rotate freely on the washer.
Rollers S, S, are provided, free to rotate on the upper bolts E, over which the
rope N can be led.
The elastic resistance to the pull of the rope on the gripping device, is constructed
as follows.r
"
T is a bolt secured in apertures in the ends C¹ of the frame, and V is a' down-
wardly projecting piece on the underside of the bed-plate H, having an aperture
through which the said bolt passes. W is a strong helical spring having its ends
supported on shouldered washers X, X', threaded on the bolt T. The washer X
bears against the end of the frame and the washer X' against the projection V.
As the bed plate H of the gripping device is free to slide in the ways C' on
the frame, and the projection V on the bolt T, it is clear that any pull on the
rope N in the direction of the arrow, tends to compress the spring W, and the said
spring is of sufficient strength to absorb any sudden or violent strain without
injury to the rope, or the apparatus. In the event of the rope breaking, while
under tension, the recoil of the spring W would throw the gripping device back,
and to prevent injury from such cause a small spring Y is provided, to act as a
buffer, and absorb the momentum of the moving piece.
In Figs. 5 and 6, representing the jaw J, Z is a liner applied to the channel M'
in the jaw, and held in place by bolts a a and a har b, or other suitable means.
This liner is formed with a channel M³, of less radius than the channel M', and
may be used with ropes of a diameter too small to be properly held by the
channel M'.
If preferred, the ways on the frame C, on which the bed plate H slides, may
consist of V shaped edges, corresponding grooves to receive them, being formed in
the bed plate.
We do not confine ourselves to the particular form of spring W, shewn, for
absorbing strains or sudden resistances, as volute, or any other suitable form of
springs may be employed for this purpose.
Our apparatus may be used for holding fast any rope, chain, or cable employed
in hauling, or making fast any vessel, or other required body.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim, is:-
1. The combination with a gripping device, consisting of a bed plate H and
jaw J, secured by a screw P and nut Q, of an elastic resistance device, substantially
as and for the purpose herein set forth.
2., An apparatus of the class described, consisting of the combination of a
frame C, a gripping device adapted to slide in said frame, and a spring forming
an elastic resistance thereto, substantially as and for the purpose herein
set forth.
3. An apparatus of the class described, consisting of the combination of a
frame C with ways C2, a gripping device having a projection V and adapted to
slide in said ways, a bolt T, springs W and Y and rollers S, substantially as herein
described and shewn in the accompanying drawings.
4. In an apparatus of the class described, the combination with an elastic
resistance device, of a buffer spring Y, substantially as and for the purpose herein
set forth.

page_text: 5. The combination with a screw P and nut Q, of a washer R, having pro-
jections R' engaging with an annular groove in said nut, substantially as and for
the purpose herein set forth.
6. The combination with the jaw J of a gripping device as described, of a
liner Z, substantially as and for the purpose herein set forth.
Dated this 5th day of March 1896.
AMBROSE MYALL,
2 Lancaster Place, London, W.C., Agent for the Applicants.