An Improved Combination Plumb, Level and Angle Indicator,
Year: 1899

page_text: Date of Application, 27th May. 189) - Accepted, 1st July, 1899
COMPLETE SPECIFICATION.
An Improved Combination Plumb, Level and Angle Indicator,
We, SILAS THOMAS TALL, of Sunnyside, Mannamead, Plymouth, Gentieman, and
THOMAS WILLIAM Box, of 11, Northcraven Avenue, Plymouth, Joiner do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention for an improved plumb, level, and angle indicator has for its
object to provide a simple combination device for use by carpenters, brick layers,
engineers, sewer layers and in other trades, which will indicate when required
the angles of sloping faces when at an angle with the horizontal or vertical line
and take the place of the separate devices at present in use.
Moreover the device
is not affected by wind as is the case with the ordinary plumb bob.
According to this invention a weighted pendulum is mounted within a casing
upon pivots. The casing is closed except over a pointer where a sheet of glass,
celluloid, or other transparent material is fitted and the pointer is arranged to
move over a graduated are or semicircle so that the angle is clearly indicated of
the work against which the device is placed.
The casing is preferably bound on the edges with metal. A thumbscrew serves
to hold the pendulum to one side when not in use. It is essential that the vertical
sides of the casing be parallel with the pendulum when pointing to 90° on the
scale and the top or bottom, or long sides of the casing must be at right angles
with the vertical line. This device also serves to indicate the amount out of
plumb or out of level of a surface on the system of so many degrees to the inch,
on a suitable scale.
In order that a rule may be attached to the casing to facilitate the use of this
device, holes are made in the casing through which screws or pins can be passed.
In order that this invention may be more readily understood reference is had
to the accompanying sheet of drawings on which
Fig. 1 is an elevation of our combination plumb level, and angle indicator,
Fig. 2 is a cross section of same and
Fig. 3 shows a modification of our invention intended to take the place of the
ordinary plumb bob.
The pendulum A is fitted upon the supporting points bb of the screw pins B B
and is weighted at its extremity so that it always tends to take a vertical position.
The points bb of the pins B B and the adjacent portions of the pendulum A into
which they take are preferably of hardened steel or the like so as to minimise the
friction to the utmost. The casing C is of mahogany or other well seasoned wood
and is preferably air tight or sufficiently so that there is no possibility of the pen-
dulum A within it being influenced by wind. The front of the casing C is slotted
out and a piece of glass or transparent material 1) fitted in a rebate, so as to cover
the slot, allowing the movement of the extremity of the pendulum A to be clearly
geen. A graduated scale E is also fitted under the glass to show the angle at
which the pendulum A hangs. The front of the casing C may be of wood or of
metal to give it greater strength to resist hard usage. The sides of the casing (
should as before stated be made accurately square and parallel to a true vertical
line and are preferably provided with metal edging C₁ C. By placing the long

page_text: sides of our instrument upon the bed or softite of any building work it will show
whether or not it is parallel to the horizon and by placing the shorter or vertical
sides of our instrument against any work such as brick work or the like it will
indicate if the same is in a true vertical plane or at what angle the said work is
to the horizontal plane and in this latter case it will do the work of the ordinary
plumb line.
The countersunk holes cc allow for attaching our instrument to
rules or level boards and the like.
A rule can be attached by screws or pins passing through these holes so as to
form a continuation of the short vertical sides of the casing thus providing a means
for estimating the vertical direction of a wall or the like which could not other-
wise be done accurately owing to the small length of the side of the casing. These
holes cc must be accurately arranged so that the rule attached to the casing shall
form a correct vertical continuation of the side of the casing.
In order to prevent the pendulum from swinging about when not in use a screw
pin F is fitted in the casing in such position, that, the pendulum being turned
to one extreme position it is held in that position and thus prevented from shaking
about. Rubber pads G G minimise the shock if the pendulum A swings round
quickly and therefore prevents displacement from the pivots which might result
from a sudden jerk. This indicator can also be used for striking out all angles,
in building, carpentry and foundry work. It is also applicable for grading, stack
building, to a required batter and for many other purposes.
In the arrangement shown in Fig. 3 the invention is applied more especially
to take the place of the ordinary plumb bob. The casing H is long and narrow
and the weighted pendulum I pivoted in a similar manner to the above described
arrangement moves over the scale J, thus serving to indicate a true vertical line
or a small angle to either side. A flange K provided with screw holes k serves
for attaching to a rule, the casing H fitting in a portion cut out from the rule so
that the device can take the place of the ordinary plumb bob without being affected
by wind.
The weighted pendulum, instead of being formed in one piece enlarged at the
bottom to form a weight, may be formed by a cord or wire supported on pivots
and suspending a weight, in either of the above described arrangements, without
departing from this invention.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is:.
(1) An improved combination plumb, level, and angle indicator, comprising a
pivoted and weighted pendulum, and a graduated scale over which the pendulum
moves arranged in a comparatively air tight casing, substantially as described.
(2) An improved combination plumb, level, and angle indicator, comprising the
weighted pendulum A supported on the points bb of the pins B B, a comparatively
air tight casing C provided with a glass front 1) and graduated scale E, together
with screw pin F, rubber pads G G and countersunk holes cc, substantially as
described with reference to Figs. 1 and 2 of the drawings and for the purposes set
forth.
(3) An improved plumb indicator comprising pivoted and weighted pendulum I,
a comparatively air tight casing H, scale J, and flange K having screw holes k
for attaching to a rule substantially as described with reference to Fig. 3 of the
drawings and for the purposes specified.
Tand the 0041
1
1000
GEO. H. RAYNER,
37, Chancery Lane, London, Agent for the Applicant.