Improvements in Screw Bolts.
Year: 1893

page_text: Date of Application, 21st Jan., 1893
Complete Specification Left, 3rd Oct., 1893-Accepted 11th Nov., 1893
PROVISIONAL SPECIFICAITON.
Improvements in Screw Bolts.
I, WILLEM FREDERIK DANIEL VAN OLLEFEN of 35 Hoogte Kadijk
Amsterdam in the Kingdom of Holland, Ship and Engineer Surveyor to Lloyd's
Register of British and Foreign Shipping do hereby declare the nature of my
invention to be as follows:-
The object of my invention is to so make screw bolts that the nut is not liable to
work loose or its liability to work loose is much lessened.
I effect the object of my invention by making the bolt or that portion thereof
upon which the screw is formed of a slightly elliptical or oval section. When the
nut is screwed on the said bolt so formed the tension set up in the nut tends to
expand it in the direction of the longer axis and to contract it in the direction of
the shorter axis the molecules of the material of the nut accommodating themselves
to the elliptical or oval form of the bolt thereby making the screwed hole in the
nut also with a longer and shorter axis and so retaining the nut more securely in
place on the bolt.
Dated this 21st day of January 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in Screw Bolts.
I WILLEM FREDERIK DANIEL VAN OLLEFEN of 35 Hoogte Kadijk,
Amsterdam in the Kingdom of Holland, Ship and Engineer Surveyor to Lloyds
Register of British and Foreign Shipping 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 :-
The object of my invention is to so make screw bolts that the nut is not liable to
work loose or its liability to work loose is much lessened.
I effect the object of my invention by making the bolt or that portion thereof
upen which the screw is formed of a slightly elliptical or oval section..
When
Figure 1 of the accompanying drawing shews a plan of a bolt shewing the
difference between the longer axis a a and shorter axis b b according to my
invention. The difference is somewhat exaggerated in the drawing the said difference
in practice being very slight. I do not limit myself to any precise degree of
difference as it will vary with the size of the bolt. For example with a bolt of ths
of an inch diameter the difference may be as slight as 0.02 or 0.15 of an inch.
the nut (shewn in Figure 2) is screwed on the said bolt so formed the tension set
up in the nut tends to expand it in the direction of the longer axis and to contract
it in the direction of the shorter axis the molecules of the material of the nut when
in rest accommodating themselves to the elliptical or oval form of the bolt thereby
making the screwed hole in the nut also with a longer and shorter axis and so
retaining the nut more securely in place on the bolt.
Figure 3 shews the nut applied to the bolt.

page_text: 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 :-
A bolt for use with a screw nut the said bolt having an elliptical or oval section
substantially as and for the purpose herein before described.
Dated the 3rd day of October 1893.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, Agents.