Improvements in Lock or Jam Nuts.
Year: 1891

page_text: Date of Application, 3rd Sept., 1991
Complete Specification Left, 3rd June, 1892-Accepted, 9th July, 1892
PROVISIONAL SPECIFICATION.
Improvements in Lock or Jam Nuts.
I, CHARLES HERBERT BAXTER of Yew Tree House Sandiacre in the County
of Derby Engineer do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in lock or jam nuts and has for its object
to obtain a locking action between two nuts placed upon a stud or bolt or in other
position in such manner that in the event of the first or acting nut slacking back
from its work however slightly it will cause the second or jam nut to nip the screw
bolt or stud and immediately arrest such back action.
For this purpose I form the first or acting nut in its outer face with a conical or
other recess and I form the second or jam nut with a conical or other projection
thereon to enter the recess of the acting nut and I so shape the recess and projection
that when the two nuts are forced together the recessed part of the first nut will
act upon the projecting part of the second nut with a tendency to compress the
same upon the bolt or stud.
In order to render the projecting part of the second nut capable of compression
I either split it right down on one side and slightly compress it or form one or
several transverse saw cuts therein and I also form the bore of the nut at that part
of a diameter slightly less than that of the bolt or stud so that the split projection
will naturally nip the same with a spring pressure.
When putting my invention into practical use the first or acting nut is screwed
upon the stud or bolt and against the object to be held in place until it is in the
desired position and the second or jam nut then screwed upon the stud or bolt
until its projection enters the recess of the first nut and is tightly compressed
thereby around the nut or bolt.
By reason of the nip of the spring extension of the second nut the friction
between the same and the bolt or stud will be greater than between the first nut
and the second or jam nut and consequently the liability of the former to slacken
back will be less than of the latter and it therefore follows that any back pressure
upon the first nut will be transmitted to the second nut and will further compress
the split projection thereof upon the suud or bolt and thus securely lock both nuts
against further movement.
Dated this 3rd day of September 1891.
WHITE & WOODINGTON,
27, Southampton Buildings, London, Agents.
COMPLETE SPECIFICATION.
Improvements in Lock or Jam Nuts.
I, CHARLES HERBERT BAXTER of Yew Tree House Sandiacre in the County
of Derby 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:-
My invention relates to improvements in lock or jam nuts and has for its object
to obtain a locking action between two nuts placed upon a stud or bolt or in other
position in such manner that in the event of the first or acting nut slacking back
from its work however slightly it will cause the second or jam nut to nip the screw
bolt or stud and immediately arrest such back action.
For this purpose I form the first or acting nut in its outer face with a conical or
071

page_text: whilst the projecting part c' of the second or jam part c of the nut instead of being
formed conical is formed cylindrical, the action of the walls of the recess 6' thereon,
being similar to that hereinbefore described.
In the example given at Figure 6. the parts b c are reversed, that is to say, the
recess in the acting part of the nut is formed cylindrical whilst the projection c'
upon the second or jam parte is formed tapered; the action however is similar in
both these examples.
In the example given at Figure 7, in lieu of forming a single split or saw-cut
in the projection c¹ of the second part c of the nut, four transverse saw-cuts c² are
formed therein, so as to break up the parts c¹ into four sections thereby increasing
the elasticity thereof.
When putting the invention into practical use the first or acting part of the
nut is screwed upon the stud or bolt a and against the object (not shown) to be
held in place until it is in the desired position and the second or jam part c is then
screwed upon the stud or bolt a until its projection centers the recess 6 of the
first part b, and is tightly compressed thereby around the stud or bolt a.
By reason of the nip of the spring extension c³ of the second part c of the nut the
friction between the same and the bolt or stud a will be greater than between the
first part of the nut and the second or jam part c, and consequently the liability
of the latter to slacken back will be less than of the former and it therefore follows
that any back pressure upon the first part will be transmitted to the second part c
and will further compress the split projection c¹ thereof upon the bolt or stud a and
will thus lock both parts of the nut against further movement.
I would here remark that I do not confine myself to the precise details herein
shown and described, as it will be evident that the shape of the recess b' and of the
projection c may be varied, and that the number and arrangement of the saw-cuts
may be modified without departing from the spirit of the invention.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is;
1. In a lock or jam nut the combination of an acting part 6 formed with a
recess b¹ therein, and a jam part c formed with a split projection c¹ thereon adapted
to enter the recess b¹ of the part b, one or both of such parts being provided with
coned surfaces, substantially as herein shown and described and for the purpose
stated.
2. In a lock or jam nut the combination of an acting part 6 formed with a
recess b¹ therein, and a second or jam part e provided with a split projection c¹
thereon, formed with a bore of a diameter less than that of the bolt or stud upon
which it is to be employed, one or both of such parts being provided with coned
surfaces, substantially as herein shown and described, and for the purpose stated.
Dated this 3rd day of June 1892.
WHITE & WOODINGTON,
27, Southampton Buildings, London, Agents.