Improvements in and relating to Beam-compasses, Calipers, or like Beam Instruments.
Year: 1898

page_text: Date of Application, 9th Mar., 1898-Accepted, 18th June, 1898
Improvements in and relating to Beam-compasses, Calipers, or like
Beam Instruments.
I, THEODOR KOLBE, of Essen am Ruhr, in the Empire of Germany, Manufacturer,
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 follow-
ing statement:—
This invention relates to that class of measuring or drawing instrument known
as beam-compasses and its object is to arrange a telescopic beam carrying either
the drawing or marking instruments or the measuring instruments suitably fixed
thereon.
The accompanying sheet of drawings illustrate means for carrying the invention
into effect as follows,-
Figure 1, shows the compasses in longitudinal section.
Figure 2 is a cross section through the telescopic tubes.
Figure 3 is a detail of the telescopic portion.
Figure 4 is a view of part of the compass with a drawing pen fixed thereon.
Figures 5 and 6 are sectional views of the opposing telescopic ends of the com-
pass showing the method of attaching the measuring instruments or calipers
thereto.
The construction of the instrument is clearly shown in the longitudinal section
at Figure 1. The tube a carries at its outer extremity a shoulder piece with a
suitable hole drilled therein and a thumb screw for attaching the required instru-
ment. On the tube a a second and larger tube b is fitted and on this tube ba
third and larger tube c is also fitted, and these two tubes are held in any relative
expanded or contracted position by the thumb screws e and d attached to bosses
integral with the respective ends. The relative lengths of the three tubes a, b,
and c are so arranged that when telescoped together the outer tube c completely
encloses the two inner tubes and thus protects them from rust.
The outer tube c at its extremity carries a shoulder piece with a suitable hole
drilled in it to receive the instrument required, and a binding thumb screw
arranged at right angles thereto in the shoulder piece. In these shoulder pieces
the pencil holder and point holder shown at Figure I can be fixed and circles of
the required diameter produced or in these shoulder pieces caliper legs f f shown
at Figures 5 and 6 may be placed, and inside or outside measurements of large
dimensions easily taken. A second instrument holder may be attached to a
shoulder piece p sliding upon the outer tube c so that smaller circles of any required
diameter may be done simultaneously with larger ones. A binding screw z holds
this shoulder piece in the required position.
The advantage of this tubular construction over the beam compasses at present
in use is that great rigidity and accuracy is produced, as any tendency to the
deflection of the beam when measuring or drawing is reduced to a minimum, and
that any drawing, measuring or marking instrument employing a beam may have
this telescopic arrangement applied.

page_text: It is to be clearly understood that more than three tubes may be arranged to
be pushed one over the other according to the maximum length of extension
required in the beam compasses, and further that the tubes can be burnished or
plated as desired to protect against rust, and all without departing from the sub-
ject of the present invention.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:-
:-
1. In beam-compasses or calipers and like beam instruments providing a beam
of tubular telescopic construction with the opposing ends of the telescopic beam
carrying shoulder pieces to receive the required instruments and collars with
suitable tightening devices fastened on each tubular section to retain the beam as
a whole in any set position.
2. The improved combined beam compasses and calipers hereinbefore described
with reference to the accompanying drawings.
Date UILES OIL y
UL
MARKS & CLERK, ·
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.