Improvements in Sights for Ordnance.
Year: 1899

page_text: Date of Application, 18th Aug., 1899-Accepted, 11th Nov., 1899
COMPLETE SPECIFICATION.
Improvements in Sights for Ordnance.
I WILLIAM HENRY BEVANS, of No. 155, E. Street, S.E., in the City of
Washington, District of Columbia, U.S.A., Ordnance Engineer, 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: -
This invention relates to sights for ordnance, and the primary object thereof
is to provide an improved mechanism whereby the sight may be quickly and
accurately adjusted, and to minimize the number of parts employed in such
mechanism, thus simplifying the same, and effecting a reduction in weight and
in cost of manufacture.
The invention also consists in certain other improvements which will be fully
set forth in the following specification, particularly pointed out in the claims,
and clearly illustrated by the accompanying drawings, in which,
Figure 1 is a top plan view of my improved sight in position upon the trunnion
of a gun.
Figure 2 is a side elevation of the same.
Figure 3 is a transverse sectional view taken on the line of Figure 2.
Figure 4 is a similar view taken on the line y of the same figure.
Figure 5 is a top plan view showing my sight provided with means for effecting
the lateral adjustment thereof.
Fig. 6 is a side elevation of the same.
Figure 7 is a transverse sectional view on line of Figure 6.
Figure 8 is a similar view taken on the line y of the same figure.
Figure 9 is a top plan view, with the telescope and elevating drum removed.
Figure 10 is a side elevation of the same.
I have illustrated and described my invention in the present instance, in
connection with that class of sights known as telescope sights, but do not desire
to limit the same to that class, as it is equally applicable to other forms of sights.
Referring now more particularly to Figures 1, 2, 3 and 4 of the drawings, 1
designates a supporting plate having the laterally extending trunnion-bearings 2
formed at one end thereof, and at its opposite end the laterally extending boss 3.
A telescope 4, such as is ordinarily in telescope sights, is pivotally.mounted upon
said supporting plate, through the medium of the trunnions 5, projecting from a
trunnion-band 6 secured about the body or main tube of the telescope, and
engaging said trunnion-bearings, in which they are retained by caps 7.
A shaft S is threaded into boss 3, and at its outer end is reduced and threaded
as at 9, and at the inner end of said threaded portion, formed with an annular
shoulder 10.
Mounted upon shaft 8, is an elevating disk or drum 11, the hub of which is
counterbored to receive shoulder 10 of the said shaft. A suitable clamping
nut 12 is adapted to lock the drum or disk from movement upon said shaft after
the sight has been adjusted.
Formed in said disk or drum, about the center thereof, is a spiral slot 13, into
which projects a pin 14 carried by an elevating band 15, also secured upon the

page_text: body of the telescope. This pin projects from a laterally extending lug 16 upon
said elevating band, which lug is formed with a flat bearing surface engaging
the inner face of the drum or disk, while a similar lug 17 is formed on the
opposite side of the elevating band, the bearing surface of which engages a
vertical guide-extension 18 formed on the supporting plate. Thus as the telescope
is elevated and depressed, it is guided in its movement by the engagement of said
lugs with the inner face of the disk and guide extension."
The elevating disk or drum is provided about the outer edge of the spiral slot
with a scale, the graduations of which are brought into coincidence with an
index or pointer upon the end of pin 14, as said disk or drum is rotated.
When it is desired to adjust the telescope to insure the proper elevation of
the gun for an object at a distance of, say two thousand yards, the elevating disk
or drum is rotated, its periphery being milled to facilitate the same, until the two
thousand yards graduation of the scale coincides with the index upon the pin,
when the sight will be elevated the requisite number of degrees. Thus it will
be seen that the elevation and depression of the telescope is effected through the
medium of the pin carried thereby and the spiral slot of the elevating disk.
Owing to the fact that the pin carried by the sight, is at all times above the
axis of the elevating disk, the weight of the sight will cause the same to be
retained in its adjusted position without the use of the clamping nut, the latter
not being essential, but provided as a safe-guard to positively lock the sight from
any movement which might possibly occur from the shock or vibration incident
to the firing of the gun to which it is attached.
Through the medium of the spiral elevating slot, an increased scale surface
is provided, so that the graduations may be placed quite a distance apart, thus
permitting the sight to be quickly and accurately adjusted, by facilitating the
reading of the scale and necessitating a considerable movement of the elevating
disk to elevate or depress the telescope a single degree.
For attaching the sight to the gun, I place at any suitable and preferred position
upon the latter (it being illustrated in the present instance as positioned upon
the trunnion of the gun) a bracket 19 having an open-ended dove-tailed groove
formed therein, and secured to or formed integral with the supporting plate, a
dove-tailed plate 20 which slides in the groove of the bracket, thus positioning
the sight upon the gun. The supporting plate is formed with a hollow boss 21
which opens through the dove-tailed plate, and in which a plunger 22 is posi-
tioned, the same being held normally projected from said plate by a coiled spring
within the boss. The projecting end of this plunger enters an opening formed
in the bracket as the sight is positioned upon the gun, and in removing the sight
from the gun, the plunger is retracted, it being provided with a suitable knob
for that purpose. It will be noticed that the face of the dove-tailed plate 20 is
inclined, and the same is so formed for the purpose of giving the sight the
proper set in order to compensate for the drift or lateral deviation of the gun.
In Figures 5 to 10 inclusive, my improved sight is shown provided with a
lateral adjustment, in addition to the vertical adjustment before described, and
through the medium of this construction the sight may be adjusted laterally, and
also be readjusted to proper position with respect to the gun, should it become
accidently displaced from any cause.
In the sight illustrated in said figures, the supporting plate is provided at its
upper edge with a laterally projecting shelf 23 upon which trunnion-bearings 2
are swiveled, through the medium of a pivot-pin or stem 24 depending centrally
from said bearings and having its bearings in the shelf, through which it depends
and receives a nut on its projecting end.
An arm 26 extends rearwardly from the trunnion-bearings, and upon
this arm,
adjacent to its free end, the boss 3 is formed which carries the shaft of the
elevating drum.
The mounting of the telescope upon the trunnion-bearings, and the mechanism
for-elevating and depressing it has been described hereinbefore, the only difference

page_text: In construction between the sight first described and the one now under considera-
tion, being the slight change incident to the swivelling of the telescope and its
elevating and depressing mechanism to the supporting plate.
A pin 27 depends from the free end of the arm 26 and moves in a curved slot 28
formed in the shelf, and is provided upon its projecting end with a clamping
nut 29, whereby the telescope may be locked in its adjusted position. A boss 30
is raised about said slot, upon which said arm moves, and a scale may be provided
therein with which an index upon the arm may coact, so that the telescope may
be readily adjusted the desired number of degrees to the right or left.
It will be apparent that the lateral movement of the telescope could be effected
in a number of different ways, other than that here shown and described, as for
instance, through the medium of a rack and pinion, and I therefore do not desire
to limit my invention to the details of construction herein set forth, for accom-
plishing such adjustment.
The guide-extension which guides the telescope in its elevation and depression,
is carried by the inner end of the drum shaft boss, instead of being formed on
the supporting plate, as in the first construction described.
The
The mounting of the sight upon the gun has been hereinbefore described, the
plunger 22 in the present instance being located below the rearwardly extending
arm, so that ready access is afforded to the knob for retracting the same.
dove-tailed plate however, is not inclined in the present construction, but the
proper set of the sight to compensate for the lateral deviation of the gun, is
provided for by forming the trunnion-bearings at an angle to the stem or pivot-
pin thereof, so that the sight is not only supported at the necessary angle to the
gun, but the axis thereof retains the same relative position with respect to the gun
throughout the lateral movement of the sight, which would not be the case were
the supporting plate and shelf set at an inclination, in which event the axis of
the sight would raise or lower during lateral movement.
As stated at the beginning of the specification, the construction described and
illustrated is not limited to use upon telescope sights, and it will be apparent
that the sight-bar might be readily substituted for the telescope without materially
altering the details of construction.
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 an adjustable sight for ordnance, the combination with an elevating
member formed with a cam surface and having a scale following the contour of
said surface, of an elevating member engaging said surface and carrying an index
coacting with said scale, substantially as described.
2: In an adjustable sight for ordnance, the combination with an elevating
member formed with a spiral elevating surface and having a scale following the
contour of said surface, of an elevating member engaging said spiral surface and
carrying an index coacting with said scale, substantially as described.
3: In an adjustable sight for ordnance, the combination with an elevating
member formed with a cam surface and having a scale placed along the edges
thereof, of an elevating member engaging said cam surface and carrying an index
coacting with said scale, substantially as described.
4: In an adjustable sight for ordnance, the combination with an elevating
drum formed with a cam surface and having a scale following the contour of said
surface, of an elevating member engaging said cam surface and carrying an
index coacting with said scale, substantially as described.
5: In an adjustable sight for ordnance, the combination with an elevating
member formed with a cam surface and having a scale following the contour of
said surface, of an elevating member carried by the sight engaging said surface
and carrying an index coacting with said scale, substantially as described.
6: In an adjustable sight for ordnance, the combination with an elevating

page_text: member formed with a cam slot and having a scale following the contour of said
slot, of an elevating member projecting into said slot and carrying an index
coacting with said scale, substantially as described.
7: A sight for ordnance constructed substantially as herein shown and
described.
Dated this 16th day of August 1899.
J. P. BAYLY,
18, Fulham Place, London, W., Agent for the Applicant.