Improvements in Holders for Object Glasses and Lens Tubes.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Holders for Object Glasses and Lens Tubes.
I JAMES SWIFT of 81 Tottenham Court Road, London, Scientific Instrument.
Maker, 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 this invention is to provide simple and efficient means for securing
object glasses and lens tubes to microscopes, cameras, or other scientific instruments,
and the invention consists in forming the lens socket with a fine thread round one
half of its interior surface, and adapting to the other portion a threaded block
which is thrust forward to grip the lens tube by means of a cam action.
In the accompanying drawing I have shown several modes of carrying out my
invention as applied to a microscope ;-thus
Fig. 1 is a vertical section;
Fig. 2 is a plan view looking from the front; and
Fig. 3. is a side elevation of one form of holder.
Figs. 4 and 5 shew in plan view, partly in section, the two parts separated.
Fig. 6 is a plan view; and
Fig. 7 a side elevation of another mode of carrying out my invention,
Figs. 8 and 9 showing the parts separated and in plan view.
Fig. 10 shows another arrangement in plan view, and
Figs. 11 and 12 show the two parts of the holder separated and in plan view.
Figs. 13 and 14 show in plan view and side elevation, a fourth mode of carrying-.
out my invention.
The same letters of reference will apply to corresponding parts in all the
figures.....
.
Referring to Figs. 1 to 5, A is a socket or holder, provided, at A', with an
external thread, by which it may be secured to the barrel of the microscope.
Internally, this socket is threaded for about half its circumference (see A²), the
remaining portion being plain, and cut away, say, the depth of the thread (see A³).
In the plain portion A, an opening A is made, and externally of the part A is a
peripherical groove As (see Fig. 1).
B is a spring which is secured in the groove A³, and carries at its free end a
block C (see Fig. 4). This block projects through the opening A', and its face is
threaded to correspond with the part A² (see Fig. 1).
D is a collar, which is formed internally with a snail cam recess D¹ (see Fig. 5)..
and is fitted onto the part A of the holder or socket.
The outer periphery of the collar is milled, for convenience of turning, and it is
secured in position by the rebated ring D³, which fits over a flange of the part A,.
and is secured to D by screws or otherwise.
To fit the object glass into the holder, the collar D is turned so as to allow the
block C, under the influence of its spring, to withdraw into the deep portion of
the snail cam recess, that is to say, in a position somewhat approaching that shown
in Fig. 4. The object glass is then placed in the socket A, so that its screw thread
will intermesh with the part A². The collar D is then turned in the contrary
direction, and, by reason of its cam surface, forces out the block C, and causes it
to intermesh with the thread on the object glass, thereby holding the object glass
securely in position.
In the arrangement shown at Figs. 6, 7, 8 and 9, the threaded portion A² is in
two parts; a portion A* of the part A is made to spring, and carries the block C;
a projection D on the collar D overrides the spring, and forces, out the block C,.
when the collar is turned.

page_text: In the arrangement shown at Figs. 10, 11 and 12, the block C is mounted at one
end of a lever C' (see Fig. 12), which is pivotted to the part A, and fits into a
rectangular recess D* in the collar D. As the collar D is turned, this recess acts
as a cam surface to rock the lever in either direction, to push out or withdraw the
block C.
In this instance, the collar is rebated, instead of the ring D³, to receive or fit
over the flange of the socket A, and the block C is operated by direct action in
both directions.
In the arrangement shown at Figs. 13 and 14, the portion A* of the part A³ is
made to spring, and carries the block C, as in the second arrangement. The
movement of the block C is caused by the excentric.cam E, which is pivotted to
the part A in rear of the block C.
The object glass is placed in the holder, when the cam is in the position shown
in the drawing, and is secured by pushing over the tail piece E¹ in the direction of
the arrow.
In Fig. 14, G represents the barrel of the microscope.
Although I have referred more particularly. to threaded portions A and C, it
will be obvious that these parts may also be undercut, to receive corresponding
portions of the object glass."
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is :-
1st. In a holder or socket for object glasses or lens tubes, the combination of
fixed threaded or undercut portions with moveable threaded or undercut portions
operated by a cam action, as hercin shown and described.
2nd. The means substantially as herein shown and described, for securing object
glasses or lens tubes in microscopes and other scientific optical instruments.
"
Dated this 9th day of June 1892.
NEWTON & SON..
Agents for the Applicant.