Year: 1896

page_text: I, JOHN JACKSON, of Warborough, near Wallingford, in the County of Berks,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to pressure and vacuum gauges, and is designed to simplify
the construction and increase the efficiency of the eume.
In the Specification of former Letters Patent granted to me and dated
29th April 1890, No. 6573, I have described a pressure or vacuum gauge in
which the free end of the curved tube or tubular chamber is connected, by means
of a link, with an adjustable piece secured upon one arm of a pivoted lever, the
other arm whereof consists of a toothed segment and is geared with a pinion fixed
on the spindle or arbor of the index or pointer.
One object of my present invention is to construct an eccentric gauge (that is
to say, one wherein the spindle or arbor of the index or pointer is placed
eccentrically) in such a manner as to obtain a long range of movement of the
index or pointer with a curved tube or tubular chamber extending around only
about one-half of a circle and without the use of toothed gearing.
My improvements are, however, also applicable to gauges in which the index or
pointer is mounted centrally.
The essential feature of my said invention is the combination, with the curved
tube or tubular chamber and with the spindle or arbor of the index or pointer, of
a multiplying system of levers and links for connecting the said tube with the said
arbor.
By my improvements above mentioned, I provide for obtaining, without the use
of toothed gearing, an ample range of movement of the index or pointer, in
gauges having an eccentric dial and index or pointer, by means of a curved tube
which extends through only one-half of a oirole, so that I can make the said tube
of greater thickness than heretofore, and the water of condensation will flow out
of the said tube, instead of being retained therein as is the case when such tube
extends around more than one-half of a circle. Moreover I ensure a very smooth
and uniform motion of the parts.
My improvements are applicable to steam, hydraulic, gas and other pressure-
gauges and also to vacuum gauges.
Dated the 22nd day of April 18006
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.

page_text: 1
Improvements in Pressure and Vacuum Gauges.
I, JOHN JACKSON, of Warborough, near Wallingford, in the County of Berks,
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 :-
My invention relates to pressure and vacuum-gauges, and is designed to simplify
the construction and increase the efficiency of the same.
In the Specification of former Letters Patent granted to me and dated
29th April 1890, No. 6573, I have described a pressure or vacuum gauge in
which the free end of the curved tube or tubular chamber is connected, by means
of a link, with an adjustable piece secured upon one arm of a pivoted lever, the
other arm whereof consists of a toothed segment and is geared with a piniou fixed
on the spindle or arbor of the index or pointer.
One object of my present invention is to construct an eccentric gauge (that is to
say, one wherein the spindle or arbor of the index or pointer is placed eccentrically)
in such a manner as to obtain a long range of movement of the index or pointer
with a curved tube or tubular chamber extending around only about one-half of a
circle and without the use of toothed gearing.
My improvements are, however, also applicable to gauges in which the index or
pointer is mounted centrally.
The essential feature of my said invention is the combination, with the curved
tube or tubular chamber and with the spindle or arbor. of the index or pointer, of
a multiplying system of lovers and links for connecting the said tubo with the said
arbor:
T
In the accompanying drawing I have shown bow. my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a front elevation of one form of my improved pressure-gauge with
an eccentric index or pointer, the dial and other parts being removed.
Figure 2 shows a portion of Figure 1, with the moving parts in a different
position.
Figure 3 is a similar view to Figure 1 illustrating another form of my improved
pressure-gauge with a central index or pointer, and
Figure 4 shows a portion of Figure 3, with the moving parts in a different
position.
A is the tubular stem to which the other parts of the gauge are attached; B is
the curved tube or tubular chamber.; C is the arbor of the index or pointer.
On the said arbor C is formed or fixed a short crank D, the pin whereof is
connected by a link E to the end of one arm F of a lever F, F' pivoted at F' to
a bracket A¹ formed on or attached to the stem A. The other arm F¹ of this
lever has fitted upon it an adjustable block or piece H similar to that described in
my said former specification, which block or piece is secured in position by means
of a sel-screw J; and is connected through a link K with a curved extension B' of
the. tube B. A counter-weight is preferably. screwed upon the arm F' to
counter-balance the weight of the longer arm F.
In Figures and 21 have shown my improvements applied to a gauge in which
an eccentric dial is used and the index or pointer is placed eccentrically. It will
be seen that the distance from the pivot F of the lover F, F to the point of
connection thereof with the link K, is about one-third of the distance from the
said pivot to the point of connection of the said lever with the link E; therefore
the movement imparted from the free end of the curved tube B will be multiplied,
and consequently the range of movement of the eccentrically-mounted index or

page_text: pointer will be greater than in the eccentric gauges hitherto constructed, notwith--
standing the fact that the curved tube is much shorter than those usually employed
in such gauges.
By adjusting the block or piece H on the lever F, F1, this range of movement.
can be varied as desired.
In Figures 3 and 4 I have shown my improvements applied to a gauge in which.
the index or pointer is placed centrally and a concentric dial is used. I find it
advantageous, in this case, to bend or curve the link E as shown, so that the
crank D and the index or pointer can be turned through an angle of nearly
180 degrees. A link of this form can also, if desired, be used in my improved
eccentric gauge herein before described.
By my improvements above described, I provide for obtaining, without the use.
of toothed gearing, au ample range of movement of the index or pointer, in-
gauges having an eccentric dial and index or pointer, by means of a curved tube
which extends through only about one-half of a circle, so that I can make the said
tube of greater thickness than heretofore, and the water of condensation will flow
out of the eaid tube, instead of being retained therein as is.the case when such.
tube extends around more than one-half of a circle. Moreover I ensure a very
smooth and uniform motion of the parts.
My improvements are applicable to steam, hydraulic, gas and other pressure-
gauges and also to vacuum-gauges.
Having now particularly described and ascertained the nature of my said inveu--
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. A pressure or vacuum gauge wherein the onrved tube or tubular chamber-
is connected through a multiplying system of levers and links with a crank on the
arbor of the index or pointer, substantially as heroinbefore described.
Second. The improved pressure or vacuum gauge constructed substantially as
described with reference to Figures 1 and 2, or to Figures 3 and 4 of the
accompanying drawing and operating as above specified.
Dated the 25th day of January 1897.
JOHN JACKSON.
D. Young & Co.,
11 & 12 Southampton Buildings, London, W.C.,.
Agents for the Applicant.