Improvements in Micrometer Gauges.
Year: 1889

page_text: Date of Application, 29th May, 1889
Complete Specification Left, 28th Feb., 1890-Accepted, 26th Apr., 1890
PROVISIONAL SPECIFICATION.
[Communinicated from abroad by LAROY SUNDERLAND STARRETT, of 160, Main
Street, Athol, Massachusetts, United States of America, Manufacturer of Fine
Mechanical Tools.]
Improvements in Micrometer Gauges.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co., Patent Agents,
of 45, Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:-
This invention relates to the class of finely graduated measuring gauges in which
a threaded spindle has heretofore been made adjustable, in respect to its distanco from
a fixed head by rotation only. With the fine screw-thread required by the nicety of
these instruments, the longitudinal movement of the spindle is very slow. It is the
object of this invention to speed this movement, and to provide for instantaneous
adjustment of the spindle over the whole or any part of its axial path, without
rotation.
The barrel or body of the instrument is tubular, without longitudinal slots, and is
threaded internally to form a stationary nut. The rotating spindle is recessed in its
enlarged part within the barrel to receive two pivoted jaws externally threaded,
forming the screw. These jaws are pressed outwardly into engagement with the
internally threaded barrel by an axial plunger forced forward between the jaws by a
spiral spring thus automatically making a perfect fit between the screw and nut.
These parts are instantly disengaged by withdrawing the plunger from contact with
the jaws, which is effected by pressing the thumb and finger between the rotary sleeve
and the terminal knob on the outer end of the plunger rod, whereupon another spring
brings the jaws together and releases them from the female thread.
By this invention the spindle may move longitudinally through its entire course
without rotation, when the jaws are disengaged, and may be adjusted to any position
by the usual screw action when they are engaged.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Micrometer Gauges.
I, HENRY HARRIS LAKE of the firm of Haseltine Lake & Co., Patent Agents,
Southampton Buildings, in the County of Middlesex, 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 :-
This invention relates to the class of finely graduated measuring gauges in which
a threaded spindle has heretofore been made adjustable, in respect to its distance from
a fixed head, by rotation only. With the fine screw thread required by the nicety of
the instruments the longitudinal movement of the spindle is very slow. It is the
object of this invention to increase the speed of this movement, and to provide for
instantaneous adjustment of the spindle over the whole or any part of its axial path,
without rotation.
The barrel or body of the instrument is tubular without longitudinal slots and
threaded internally to form a stationary nut. The rotating spindle is recessed in its
enlarged part within the barrel to receive two pivoted jaws externally threaded

page_text: forming the screw. These jaws are pressed outwardly into engagement with the
internally threaded barrel by an axial plunger forced forward between the jaws by a
spiral spring, thus automatically making a perfect fit between the screw and nut.
These parts are instantly disengaged by withdrawing the plunger from contact with
the jaws, which is effected by pressing the thumb and finger between the rotary sleeve
and the terminal knob on the outer end of the plunger rod whereupon another
spring brings the jaws together and.releases them froin the female thread.
By this invention the spindle may move longitudinally through its entire course
without rotation when the jaws are disengaged, and may be adjusted to any position
by the usual screw action when they are engaged.
This invention consists of the devices and combinations of devices herein set forth.
In the accompanying drawing,
Figure 1 is an enlarged longitudinal section of my improved micrometer..
Figure 2 is a side view of the same.
Figures 3 to 8 are perspective details hereinafter described, and
Figure 9 a transverse section on line - Figure 1.
A represents the anvil or head of the instrument, B the usual curved neck, and C
the stationary tubular body or barrel formed integral with such neck threaded inter-
nally and graduated at c in a line of minute fractions of an inch. This barrel is not
split or slotted longitudinally as is customary in similar cases, and hence. a material
advantage is gained by the absence of such openings through which dust, emery and
other foreign matters commonly work into the screw threads, causing inaccuracy and
clogging of the movement.
Outside of the fixed barrel is the rotating sleeve D beveled at its inner end and
graduated peripherally as at in the usual way. The outer end of this sleeve is
secured to the milled head E of the rotary spindle F, so that said parts revolve
together, the spindle passing through and turning within the barrel Cand the sleeve D
revolving outside of it.
The middle portion of the spindle has a recess G entirely through it, as in Figures 1
and 5 and in this recess I pivot the two externally threaded jaws H which constitute
an adjustable screw adapted to engage with the internal threads of the stationary
barrel C or to be disengaged therefrom by the operator. The pivot I which unites
said jaws and connects them to the spindle is near their unthreaded end. A plunger K,
extending axially from the outer end of the spindle, is pressed between the diverging
ends of the jaws H by a coiled spring L, such pressure holding the jaws apart, with
their threaded surfaces engaging, with the threaded interior of the barrel, and the
instrument in condition for use by rotary movement of the spindle.
To disengage the jaws, and permit adjustment by a quick sliding movement, the
plunger rod Jis prolonged through and beyond the head E of the spindle and
furnished with a knob M by which the plunger may be withdrawn slightly against the
resistance of the spring L, such withdrawal leaves the jaws free to come together at
the axis of the barrel C,-a movement which is ensured by the employment of a short
spring N placed transversely between and compressed by the short ends of the jaws
beyond their pivot I. This latter spring is of less power than the one which acts to
press the plunger forward, so that under ordinary conditions of use the plunger keeps
the jaws expanded and engaged with the threaded barrel. Disengagement is readily
effected by pressing the thumb and finger between the head E and knob M. The
plunger rod runs through a screw plug P which may be screwed more or less into the
head Esto vary tension of the spring L, which bears against it.
:
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, as communicated.to.me by
my foreign correspondent I declare that what I claim is :-
"
First. In a micrometer gauge the combination of an internally threaded barrel and
the rotary spindle provided with a pair of hinged and externally-threaded jaws,
substantially as and for the purpose; set forth.

page_text: Second. In a micrometer gauge an internally-threaded barrel, a revolving sleeve
and a rotary spindle provided with a recess, in combination with a split screw formed
of two pivoted adjustable jaws located in said recess, for the purpose set forth.
Third. In a micrometer gauge a solid, internally-threaded barrel graduated exter-
nally, and a revolving sleeve beveled and peripherally graduated at its inner end, in
combination with a rotary spindle carrying two adjustable screw-threaded jaws
working within said barrel and a plunger adapted to connect and disconnect such
threaded parts substantially as and for the purpose set, forth.
Fourth. In a micrometer gauge, the stationary anvil and threaded graduated barrel
with the revolving spindle and sleeve, in combination with the screw threaded, spring
actuated jaws pivoted on said spindle, and the axially-moving plunger with its terminal
knob, for the purpose set forth."
Dated this 27th day of February 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.