Improvements in Micrometer Measuring Apparatus.
Year: 1888

page_text: Date of Application, 28th June, 1888
Complete Specification Left, 29th Apr., 1889-Accepted, 28th June, 1889
PROVISIONAL SPECIFICATION.
Improvements in Micrometer Measuring Apparatus.
I, HEINRICH HORSTMANN of 7 Hanover Street Islington in the County of Middlesex
Watchmaker do hereby declare the nature of this invention to be as follows:-
According to this invention and for the purpose of obtaining and indicating very
minute and accurate measurement I employ a quick threaded screw as the medium for
imparting the motion to a hand, which indicates on a suitably divided dial. The
screw is on or in connection with a spindle mounted in bearings. In the screw thread
acts a pog or tooth which is accurately guided in a path parallel to the axis of the
screw. The hand is conveniently fixed on the end of the screw spindle and the dial
fixed on a tubular or other frame which may form a casing for the screw and a guide
for the peg or tooth. In connection with this peg I arrange or construct various other
contrivances all arranged or constructed according to the object in view. If I for
instance desire to measure the thickness or length of an article I provide the frame
with a fixed gauge peg and insert the article to be measured between this fixed und
the peg that works in the screw thread. In all cases there will be a fixed part relatively
to the movable peg. The pitch of the screw and the divisions on the dial are so
arranged or proportioned that for instance one turn of the screw spindle is indicated
by the land on the dial as a millimeter or any decimal part of an inch. A spiral
spring is connected to the screw spindle and to the frame for the purpose of
bringing the spindle and the hand back to zero. In some cases I use a short hand
for indicating the large divisions and a longer hand for indicating the finer divisions.
My invention is applicable to measuring apparatus of many kinds, to pressure
gauges, barometers, screw cutting tools and to many other purposes wherever
accurate measurement and indication are required.
1000
peg
Pake
HEINRICH HORSTMANN.
By Jensen & Son,
77, Chancery Lane, London, W.C., Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Micrometer Measuring Apparatus.
I, HEINRICH HORSTMANN, of 7, Hanover Street, Islington, in the County of
Middlesex, Watchmaker, 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:-
--
According to this invention and for the purpose of obtaining and indicating very
minute and accurate measurement I employ a screw as a medium for imparting the
motion to a band which indicates on a suitably divided dial. The screw is on or in
connection with a spindle mounted in bearings. In the screw thread acts a peg_or
tooth which is accurately guided in a path parallel to the axis of the screw. The
screw may be with uniform or increasing pitch and either with raised threads on a
spindle, or in a forin of a helical groove in a tubular spindle. The hand is con-
veniently fixed on the end of the screw spindle and the dial fixed on a tubular or
other frame which may form a casing for the screw and a guide for the peg or
tooth. In connection with this peg I provide various other contrivances all arranged
or constructed according to the object in view. My invention is thus applicable
to measuring apparatus of many kinds, to pressure gauges, vacuum gauges and
barometers, and to many other purposes wherever accurate measurement and
indication are required.

page_text: Fig. 1 of the accompanying drawings is a perspective view of an apparatus for
measuring the thickness or length of an article. The frame A of the apparatus is
provided with a fixed gange peg B, and the article to be measured is inserted
between the fixed peg B and the peg or tooth (which works in the thread of
the screw spindle D. In all the measuring apparatus constructed according to my
invention there will be a fixed part relatively to the movable pog or tooth Cl
The latter is in this instanco fixed to and passes through a slide which is
guided vertically between grooves in the frame A or in any other suitable manner
so long as the peg (" thereby is guided up and down parallel to the screw spindle D.
The point of the peg Congaging in the serus Diny be fitted with an agate or
other stone or with a roller in order to diminish the friction. The slide E is
supported on the helical springs F which tend to hold the peg C normally close up
against the peg B. A rod G is in this case supposed to be inserted between them
for the purpose of measuring its exact length. It will be understood that as the
peg C is moved away from the peg B the screw spindle D is caused to turn part of
a revolution or a whole revolution or anything more than one revolution according to
the pitch of the screw D' and to the length of measurement that the apparatus is
designed for, or the extent to which the slide E is capable of being conveniently
lowered and the dial hand H to indicate correspondingly on the dial. One turn of
the screw spindle may, for instance, correspond to an indication of a millimeter
or decimal or other part of an inch on the dial. A spring Kis coureted to the
screw spindle and to the frame A or to the bracket G which, as shewn, forms
an upper bearing for the spindle D, for the purpose of bringing the spindle D and
the hand H. back to zero. I is a hand on a smaller dial but its mode of connection
with the spindle D and hand I will be explained further on.
Fig. 2 shows another form of fixed peg B and movable peg (suitable for
measuring in places where the instrument Fir. 1 would not be admissable. In
Fig. 3 the pegs or callipers B and are formed suitable for measuring the width of
a bolo or the distance between two objects, and Fig. 34 is a detail view showing tho
extremities of the inside callipers in end view.
All these three sets of apparatus may be combined in one having one screw
spindle D in common.
Fig. 4 shows the peg Capplied to the lower part of the slide E and adapted to
measure the depth of a hole, recess or relate.
Fig. 5 is plan view, Fig. 6 side view and Fig. 7 an end view of an aneroid barometer.
On the easing or framing bottom A is mounted the vacnum chamber G of usuni
ribbed form and with central pillar E. The bent spring is at one end by a pin
connected to the top of the pillar B and at the other end to the bar which is pivotted
to the standards AA' and has a lover extension which is united to the bottom A
by an adjustable screw all in the usual mannor. To the upper end of spring F is
fixed the continuation bar which by a bar Fx with interposed helical spring Fis
connected to the comparatively long lever in such manner that the spring takes
up any slackness between the parts and F*. The bar Fx passes through a longi-
tudinal slot in the lover (. The upper end of the bar F has a block f which is
scrow threaded for the scrow that moves it longitudinally to work through, the
bar F being formed hollow or open so that the block can work along in it. By
turning the serow F the instrument can thus be adjusted relatively to the standard
barometer. The lever C may be connected to the standard by a pin-joint but I much
profer the connection shown, viz.: by a piece of thin blado steel which never woars
slack like a pin-joint and thus in time produces inaccuracy of action. Moreover I
give the spring blade such a downward set as to counterbalance the friction for
turning the screw D' round, and the power of the spring K so that the chamber G
has the least work to do. The lever Ubas a tooth which gears with the scrow D.
The screw spindle D is mounted in an upper and a lower bearing in the part A3 which
is fixed to part of the easing or framing. On the upper end of the spindle D is
fixed a dial hund H which indicates on a suitably divided dial. The latter, in the case
of a barometer, would only have a few main divisions in the circle say from 27 to 31

page_text: and the requisite intermediate divisions. On the large dial is hy preference also
arranged a small dial with hand I on the spindle of which is fixed a pulley M round
which passes a hair or fine wire passing along to and round the upper end of the screw
spindle D the other end of the hair being connected to the fine spring K the
other end of which is fixed to the part A². The proportion of the diameter of
the spindle D and of the pulley M is such that the dial hand I will make say
one turn for each four turns of the spindle D and hand H. The small dial is
divided from say 16 to 31. The thread D' on the spindle D is left handed and
has a downwardly increasing pitch, whereby 1 can ensure equal division of the
dial or dials.
It will be understood that the arrangements of screw spindle D, lever C and
counteracting and retracting springs herein before described are applicable to
pressure gauges and vacuum gauges and the like having a chamber with ribbed or
elastic face; and that the arrangement of parallely guided peg (described with
reference to figure 1 can be adapted to aneroid barometers.
If the screw spindle D is made tubular and with an increasing pitch I am able
to extend or compress it lengthwise more or less so as to adjust the pitch to the
exact requirements that is to say so as to counteract the losing power of the
spring F when it opens which is useful in very accurate instruments for measuring
length and other dimensions and for measuring weights, say for apparatus for
weighing coin, chemicals, diamonds, letters, and other objects and materials.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is ;-
Firstly. The application and use of a solid or tubular spindle provided with
screw thread of uniform or varying pitch and having a dial band directly or
indirectly connected thereto, in combination with a peg or tooth which is guiled
in a path parallel to the axis of the screw in such manner that the motion of the
peg or tooth causes the screw spindle to rotate and the dial land to indicate,
substantially as and for the purposes set forth.
Secondly. The application and use of a solid or tubular spindle provided with
screw thread with varying pitch and having a dial hand directly or indirectly
connected thereto, in combination with a peg or tooth on the end of a compara-
tively long lever substantially as and for the purposes set forth.
Thirdly. In combination with the apparatus as firstly or secondly claimed the
application and use of a secondary dial and hand which latter is actuated by a
hair or fine wire connection from the screw spindle and its retracting spring to a
pulley on the secondary dial hand spindle substantially as set forth.
Fourthly. In combination with apparatus as firstly claimed the application and
use of a fixed peg or part relatively to the movable peg or tooth substantially as
and for the purpose set forth.
Fifthly. In fluid pressure or vacuum indicating apparatus actuated by appliances
as firstly or secondly claimed the means for adjusting the counteracting spring
pressure relatively to the opposing fluid pressure substantially as set forth.
Sixthly. The constructions of measuring apparatus shewn and described.
Seventhly. The constructions of fluid pressure or vacuum indicating apparatus
shewn and described.
Eighthly. In apparatus as hereinbefore referred to the application and use of
a hollow screw threaded spindle with varying pitch, such spindle being provided
or connected with a dial hand and used with a peg gearing therewith, the form
of screw spindle giving facility for adjustment of the pitch, by extending or
compressing the screw spindle substantially as and for the purposes set forth.
Dated this 20th ...
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.