Year: 1898

page_text: www.
ALFRED BULT ALLEN, Holly Bank Works, Crescent Road, Tunbridge Wells,
Microscope Manufacturer, do hereby declare the nature of this invention to be
as follows:-
-
An improved form of combination of fittings and parts making as a whole what
is termed a mechanical stage, is constructed in such a way as to be easily adapt-
able to any ordinary plain stage of a microscope. When adapted to a plain
stage of a microscope, a glass or other microscopic object slip, placed on the
plain stage and held by the mechanical stage can be moved in rectangular direc-
tions, hereinafter termed vertical and transverse movements. A dovetailed
fitting and slide are constructed and attached to a microscope stage by a suitably
shaped arm with screws. The dovetailed fitting to which the aforesaid arm is
fixed is arranged to lie close to the side of, and flush with the top face of the
stage, so that a straight edge laid on the top face of the stage, will not come in
contact with the topside of the dovetailed fitting and slide. I do not however
confine myself to construct and apply the dovetailed fitting and slide in this
position only, I may, for instance, so construct and apply the dovetailed fitting
and slide so that a space is left between the top face of the stage and the underside
of the dovetailed fitting, this space to be sufficient to allow a glass or other
microscopic object slip or carrier to pass underneath the said dovetailed fitting
when the said object slip is moved across and on the face of the stage, the space
being sufficient to allow the object slip to clear the underside of the dovetailed
fitting.
Having in the foregoing clearly described the manner in which I attach the
dovetailed fitting to the stage, I intend hereinafter to term, the movement
obtained by sliding the slide up and down the dovetailed' fitting, the vertical
movement.
The vertical movement is obtained by the use of a rack and pinion in the
ordinary way e.i.-A rack is fixed to the slide and a pinion gearing into the rack,
is attached to the dovetailed fitting, or a rack is fixed to the dovetailed fitting and
a pinion, gearing into the rack, is attached to the slide.
A bar or guide of sutiable length projecting partly across and just above the
top face of the stage, is fixed to the slide to act as a guide for glass or other
microscopic object slips to pass or travel across and on the face of the stage trans-
versely in a straight line; an arm being attached by means of a fitting screw
also to the slide of the dovetailed fitting, and projecting partly across and just
above the top face of the stage, and combined with a spring, by the action of
which spring the arm being kept tightly pressed against a glass or other object
slip, which in turn is pressed against the aforesaid bar.
I combine with this arm some means of easily imparting movement to the
glass or other microscopic object slip, and in order to obtain this movement I
may construct and mount on the aforesaid arm a rack and pinion, or a worm or

page_text: worms on a worm shaft gearing into a worm wheel or wheels, or
may construct
and mount at one end of the arm a grooved wheel which would be connected to
a milled head having a groove also, mounted at the opposite end of the
a cord of silk, or other suitable material.
arm, by
Providing I construct and mount a rack and pinion on the aforesaid arm, the
arm would be slotted or grooved on the edge facing the bar, to form a guide for
the rack to slide in, the rack being held in the slot and against the pinion by
a spring fixed to the arm. A pinion is mounted vertically, that is, parallel to the
body tube of the microscope, and would have a milled head or other suitable
means of easily revolving the said pinion fixed to it. A piece of cork or other
suitable material is fixed to the end of the rack nearest the centre of the stage
so that it may press on the edge and top of the object slip and form a grip upon
same. It will now be seen that by revolving the pinion the rack is moved trans-
versely across the stage in the slot or groove in the arm, and therefore when an
object slip placed on the stage in between the bar and the arm, the pressure
of the spring against the arm will press the cork or other suitable inaterial
fixed to the rack against the object slip the object slip thereby moving in conjunc-
tion with the rack. A. transverse movement to the object slip, across and on
the face of the stage is therefore obtained by revolving the pinion by means of
a milled head, or other suitable means, attached to the pinion.
Providing I construct and mount on an arm, also having a spring pressing
against it, as in the foregoing a worm or wormis on a worm shaft, the worm shaft
is mounted to gear into a worm wheel or wheels. Upon the same axis of and
to the worm wheel mounted at the end of the arm nearest the centre of the stage
is fixed a wheel with cork or other suitable material on its periphery. To the
worm shaft at the opposite end of the arm is fixed a milled head. Therefore
by revolving the milled head a rotary movement is given to the wheel with the
cork fixed on its periphery, simultaneously and in a rectangular direction. The
pressure of the spring on the arm causes the wheel to press against the object slip,
and therefore by revolving the wheel the object is made to move in a transverse
. direction across the stage. Another means of obtaining the same result is to
mount a small grooved wheel at the end of the arm nearest the centre of the stage,
and connect it with a grooved milled head placed and mounted on and at the
. opposite end of the arm, by means of a cord of silk or other suitable material.
It will be seen that by revolving the milled head, a rotary movement is also
obtained on the small wheel by means of the cord, and the wheel pressing against
the object slip will give the desired transverse movement to the object slip.
I may construct and mount the two grooved wheels as described in the fore-
going.
Dated this Comanth
T1
1000
DE PETIUALIN.
An Improved Adaptable Mechanical Stage for Microscopes.
I, ALFRED BULT ALLEN, of Holly Bank Works, Crescent Road, Tunbridge
Wells, in the County of Kent, Microscope Manufacturer, do hereby declare the 4
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 mechanical stages for microscopes and consists of
combinations of mechanism adaptable to any ordinary plain stage of a microscope
so as to convert the same into a mechanical stage whereby an object slip placed 5

page_text: thereon may be moved across the stage in the vertical or transverse direction for
the purpose of accurately bringing any part of the object into the field of view.
Both of these rectangular movements may be performed mechanically or, in the
case of a stage provided with a sliding bar, the vertical movement may be effected
directly by moving said bar in the ordinary way the transverse movement only
being performed mechanically.
For effecting the last mentioned movement two forms of device are comprised
within the present invention, the one being a pivoted arm carrying a rack-operated
propelment adapted to move the object slip transversely across the stage, in
sliding contact with a guide bar, or with the sliding bar above referred to, and
the other consisting of a pivoted arm formed of two members jointed together
so as to act as a toggle and carrying a propelment roller adapted to impart trans-
verse movement to the slip when revolved through the medium of an endless
cord kept in driving tension by the toggle-like action of the members. For the
purpose of mechanical adjustment in the vertical direction the one or other form
of arm is pivoted upon a slide having rack teeth and worked by a pinion the slide
being fitted in a guide formed by a bracket adapted to be clamped to the stage
at one side and in such position as to be wholly out of the path of the object slip
when moved transversely across the stage. Or when such mechanical adjustment
in the vertical direction is not provided, either form of arm may be pivoted to a
plain bracket fixed to one end of the ordinary sliding bar of the stage, the
bracket being situated at one side of the stage and out of the path of the object
slip when moved transversely thereon.
The invention is illustrated in the accompanying drawings forming part of this
specification wherein Figure 1 represents a plan of the one form of device as
adapted for mechanical adjustment in both the vertical and transverse directions.
Figure 2 represents a plan of the other form of device as mounted on the ordinary
sliding bar for mechanical adjustment in the transverse direction only. Both
figures are drawn to an enlarged scale; the object slips being shewn out of
adjustment, and portions of the mechanism being broken away, the better to
illustrate the construction.
gears a
Referring to Figure 1, A is the stage proper, B represents the object slip lying
thereon, Crepresents the presser arm between which and a guide bar 1) the
object slip is gripped by its top and bottom edges. In the arrangement here
shewn, the arm C is pivoted on a dovetailed slide E fitted to work in a dovetailed
groove in a guide bracket F fixed to the stage A by binding screws passing through
lugs f fixed to the said bracket the one lying on the upper, and the other on the
under, surface of the stage so as to be out of the way, and the guide bracket itself
being flush with or below the lever of the stage. Upon this slide E is also fixed
the horizontal guide bar D against which the lower edge of the object slip is
pressed and by which it is guided in its transverse movement across the stage.
The slide E is formed with rack teeth at the under side with which
pinion g formed on a spindle mounted at. the underside of the guide bracket F
and provided with a milled head G. In order to adapt the position of the arm C
to the breadth of the slip (which may, be either 1 inch or 12, inch broad) the
arm C may be pivoted not directly to the slide E but (as shewn) to a dovetailed
slide e fitted in a groove in the slide E and fixed therein in one or other of two
positions, according to the breadth of slip, by means of a binding screw e¹, the
slides e and E being adjustable together as one by means of the rack and pinion
motion. The arm C is pivoted at c to the slide e or the slide E, as the case may
be, and is formed with an angular heel end against which presses a spring c
for holding the arm in either of two positions, i.e., thrown back, as indicated in
dotted lines, to admit of inserting or withdrawing the object slip or in operative
position, as shewn in full lines, wherein it is pressed by the force of the spring
against the edge of the object slip on the stage.
The transverse propelment device for the object slip consists of a claw H pre-
ferably of the cross sectional form shewn in Figure 1, lined with cork or other

page_text: soft material so as to be adapted to grip the edge of the object slip and hold it
down on the stage, the claw being carried by a rack rod h fitted to slide in a
longitudinal groove in the arm C and in gear with a pinion formed on a vertical
spindle mounted in the arm C and turned by a milled head I, the required dead-
ness of motion being obtained by the pressure of a friction spring h
In the arrangement shewn in Figure 2 the arm C is formed of two members c², c³
the former pivoted on a stud c and spring held as before, the other jointed to
at and having mounted at its free extremity a roller K edged with leather
or cork to adapt it to bear against the edge of the object slip. Upon the spindle
of said roller K is a grooved pulley k and around the boss of the milled head. I
is another groove to receive an endless cord L of silk, the grooves in which the
cord runs being milled to ensure adhesion of the cord. The flexure of the arm C
at its joint under the tension of the cord is limited by the end of the one member
coming against a stop pin fixed on the other member and the cord being then
tight it follows that when by the pressure of the spring c¹ the roller K is pressed
against the edge of the object slip with sufficient force to cause the slip to be
moved transversely by the friction of the roller when rotated against it, the
tendency of the members to straighten will be resisted by the cord which is thus
maintained in tension by the toggle-like action of said members. This arm is
represented as pivoted to a bracket M rigidly fixed to the ordinary hand-
adjusted sliding bar N with which the plain stage is ordinarily provided, the bar
being adapted to be slid by hand in 'the vertical direction over the stage and
being guided by stiff spring tongues n attached to the downwardly projecting
ends of the bar, fitting and sliding in grooves in the edges of the stage. The
bracket M is represented as being fixed on to the upper side of this bar at one
end so that a clear space is left below the bracket to allow of the object slip in
its traversing movement across the stage passing freely beneath the bracket.
The bracket M might, however, be fixed to the underside of the downwardly pro-
jecting end of the bar N so as to lie below the level of the stage at the part where
the object clip passes across it, the end of the bracket being cranked upwards to
bring the arm C up to a level necessary to allow of the arm lying over the stage
in position to bear against the edge of the slip as above described. Preferably
the arm C is not pivoted directly to the bracket M but to a 'slide m similar to e
fitted adjustably in a guide groove in bracket M so as to adapt the position of
the arm to the breadth of the object slip.
It is to be understood that the rack propelment arm, as described with reference
to Figure 1, may also be similarly mounted on a bracket such as M when a
vertical rack adjustment is not required and that the toggle jointed arm with
driving cord and roller, as described in Figure 2, may be pivoted on the rack
adjusted vertical slide E in place of the rack propelment arm first described,
both of these alternatives being comprised within the scope of the present inven-
tion.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. In a mechanical stage for a microscope, an arm spring pressed and pivoted
as described to a bracket or support at one side of the stage and carrying a claw
operated by rack and pinion traversing motion mounted in the arm and adapted
to grip against and traverse the object slip over the stage substantially as specified.
2. In a mechanical stage for a microscope, an arm carrying a rack adjusted
claw for imparting traversing motion, the arm being spring pressed and pivoted to
a slide fitted to work in a guide bracket fixed by lugs to the stage at one side and
at or below the level thereof, a guide bar for the slip being also attached to the
slide and the whole being movable in the vertical direction by rack and pinion
adjustment substantially as described..
3. In a mechanical stage for a microscope an arm spring pressed and pivoted

page_text: to a bracket or support at one side of the stage, the arm being jointed and carrying
a friction roller for gripping and traversing the slip driven by an endless cord
kept in driving tension on its pulleys by the toggle-like action of the arm sub-
stantially as described.
4. In a mechanical stage for a microscope, a toggle jointed arm carrying a
cord driven roller adapted to operate as described, the arm being spring pressed
and pivoted to a rack adjusted slide fitted to work in a bracket mounted alongside
of and below the level of the stage and carrying a guide bar for the slip sub-
stantially as specified.
5. The mechanical stage for microscopes, formed by mounting either construc-
tion of traversing arm herein described on a bracket adapted to pass at one side
of the stage and to give clear passage above or beneath it to the object slip, the
said bracket being mounted on the end of the ordinary hand adjusted sliding bar
substantially as specified.
TL 1 L
1 - 1000
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.