Improvements in Hydrostatic Weighing Machines, Hydraulic Riveting and other like Machines.
Year: 1891

page_text: Date of Application, 11th May, 1891
Complete Specification Left, 2nd Dec., 1891-Accepted, 2nd Jan., 1892
PROVISIONAL SPECIFICATION.
Improvements in Hydrostatic Weighing Machines, Hydraulic
Riveting and other like Machines.
I, GABRIEL DAVIS, of St. Helen's Works, Abingdon, in the County of Berks,
Engineer, do hereby declare the nature of this invention to be as follows:-
This invention relates to hydrostatic weighing machines, hydraulic riveting and
other like machines; its objects being to cheapen and simplify the construction of
such machines, and to render them more effective and certain in their action.
In constructing a suspended weighing machine according to my invention, I
employ a plunger to which is connected a shackle for carrying the load while being
weighed. This plunger works in a cylinder containing a bag formed of india rubber
or other suitable compressible and elastic material. The bag is filled with water, a
mixture of glycerine and water, or other fluid, preferably of a nature not quickly
disposed to freeze or congeal. The cylinder is also provided with a shackle by
which the apparatus may be suspended. The apparatus is furnished with a gauge
which may be placed in communication with the bag by any convenient means.
cock may in some cases be provided for checking the flow of the liquid from the
bag to the gauge.
A
The apparatus may be modified in a variety of ways and may be used for weighing
articles and materials of widely different specific gravity and bulk such as timber,
loaded waggons, locomotive and other engines, and other heavy bodies, the
apparatus being multiplied according to the requirements of the case, and the
respective bags connected with a gauge (or gauges), so that the collective pressures
of the plungers may be indicated in one spot (or otherwise).
:
The main feature of my invention, namely the employment of an elastic bag
for containing a fluid under pressure, may be utilized for actuating the rams of
hydraulic riveting machines, or of any other description of hydraulic press. The
leathers or glands usually employed in this class of machines, and which require
very accurate workmanship and frequent renewal are dispensed with, a great saving
in the cost of production and maintenance being thereby effected. The leakage
incidental to the use of leathers or glands is entirely obviated by the use of a bag
for containing the fluid, and the stopping the machine when inserting new packings
is also prevented.
Dated this 9th day of May 1891
COMPLETE SPECIFICATION.
Improvements in Hydrostatic Weighing Machines, Hydraulic
Riveting and other like Machines.
I, GABRIEL DAVIS, of St. Helen's Works, Abingdon 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 :-
This invention relates to improvements in hydrostatic weighing machines,
hydraulic rivetting and other like machines, (such as hydraulic presses) and has for
its object to cheapen and simplify the construction of such machines, to avoid
leakage, and to render them more effective and certain in action.
In hydrostatic weighing machines, hydraulic rivetting, and other like machines
as at present constructed, it is necessary that the piston or plunger should fit the
FD 071

page_text: interior of the cylinder very accurately, and that leathers or glands should be
provided between the same to prevent any leakage, under pressure of the liquid,
which is introduced into the cylinder for the purpose of actuating the guage or for
propelling the plunger or piston. In hydrostatic weighing machines especially, the
friction or pressure between the leather, or gland, and the plunger, or piston, which
sustains the load (which friction or pressure necessarily diminishes or increases
according as the gland or leather becomes worn or has to be tightened) prevents
anything like an accurate indication of the weight of the suspended article, and
consequently hydrostatic weighing machines have up to the present time been con-
sidered of little practical use.
Now according to my invention I obviate these difficulties, render accurate fitting
of the plunger or piston within the cylinder unnecessary, dispense entirely with the
use of leathers or glands and their consequent friction or pressure upon the plunger,
and at the same time avoid all leakage, by the employment of a closed bag or
receptacle constructed of elastic or yielding fluid tight material, such as india rubber,
rubber and canvas composition, or leather, which is disposed within the cylinder,
and into which the liquid employed is introduced in lieu of into the cylinder direct.
A convenient pipe or pipes connected with the bag or receptacle by a fluid tight
joint permits the entrance or exit of liquid into or from the bag or receptacle as
required.
In a hydrostatic weighing machine constructed according to my invention, the
elastic or yielding bag or receptacle is compressed by the piston, or plunger, which
is caused to descend into the cylinder, through the action of gravity upon the article
to be weighed (when the same is suspended by hooks or shackles conveniently
connected with the said plunger) and the liquid flows out of the receptacle under
compression, through a convenient pipe or pipes which connects the receptacle with
a suitable pressure guage or indicator. In hydraulic rivetting and other like
machines, such as hydraulic presses, however, the receptacle in lieu of being com-
pressed by the piston or plunger is caused to expand or elongate by the introduc-
tion of liquid under pressure, and to propel the piston or plunger by its expansion
or elongation. As in cases where any considerable movement of the piston or
plunger is required, this expansion of the bag or receptacle might cause the sides of
the same and the interior of the cylinder to bind thereby preventing longitudinal
elongation of any extent, and perhaps injuring the bag, I may in some cases provide
the bag or receptacle with an encircling band, or bands, preferably of thin metal,
such band, or bands, being free to slide within the cylinder, and preventing the sides
of the bag, when the same is expanded under pressure, from binding with the
interior of the cylinder. Or the bag or receptacle may be constructed in an
accordion or bellows like form with or without metal protectors, or bindings, around
the exterior folds, this will lessen the contact surface of the bag with the cylinder,
and permit the bag to elongate more readily. In practice however the amount of
movement of the piston, or plunger, required in an hydraulic rivetter, or press, is
usually so small as to render the above described modification unnecessary. I also
prefer in applying my invention to hydraulic rivetting and like machines to provide
the top of the receptacle or that portion which bears against the head of the cylinder
with a metal shield or cover for protecting the said portion of the bag from foreign
matters.
I will now proceed to describe the application of my invention to hydrostatic
weighing machines, hydraulic rivetting, and like machines, having reference to the
accompanying drawings, in which similar letters refer to corresponding parts in all
the figures.
Fig. 1 is a front elevation of a suspended hydrostatic weighing machine con-
structed according to my invention.
Fig. 2 is a plan thereof.
Fig. 3 is a side view of Fig. 1 partly in section.
Fig. 4 is an elevation, partly in section, illustrating the application of my inven
tion to an hydraulic press or rivetter.

page_text: Figs. 5, 6 & 7 are detached sectional views, illustrating modified constructions, or
arrangements, of the yielding bag, or receptacle.
Referring to Figs. 1, 2 & 3 is the cylinder, 6 the piston or plunger; is a
shackle, by which the apparatus is suspended, which passes freely through the
head, ', of the plunger; and is secured to the cylinder, through the sides of which
it passes, by bolts d. is a shackle for suspending the article to be weighed.
This shackle e' passes freely through the sides of the cylinder a, and also passes
through the head, 6', of the plunger, to which it is secured by the bolts . The
shackles are arranged in different planes so as to clear one another, as clearly shewn
in Fig. 2; e is the fluid tight elastic or yielding bag or receptacle, preferably con-
structed of india rubber, which is filled with liquid and placed at the lower portion
of the cylinder where it is held in place by the hollow bolt, f, which passes through
a hole in the bottom of the bag, e, and is provided with a head or flange, f', which,
when the nuts are screwed up, compresses that portion of the bag e upon which
the head f¹ bears, and makes a fluid tight joint. is a pipe passing through the
bolt f, which permits the passage of the liquid contained in the receptacle e to the
pressure guage or indicator h. This pressure guage or indicator may be of
ordinary construction and is suitably graduated on its face to indicate, in any
required denominations or systems, the weight of the article suspended by the
shackle c', the pressure of the liquid in the guage h being of course proportional
to the weight of the suspended article.
The action of the apparatus is as follows:-
The weight of the article, suspended by the shackle, causes the plunger b, to
the head of which the shackle is secured, to descend.
As it descends it compresses the elastic or yielding receptacle e, and forces the
liquid contained therein (preferably of a nature not quickly disposed to freeze or
congeal such as glycerine and water or mercury) along the pipe g to the pressure
guage or indicator h, the pointer of which actuated by the pressure of the liquid,
will indicate the weight of the article.
It will be obvious that this apparatus may be modified in details in a variety of
ways without departing in any way from the spirit of my invention, and may be
employed for indicating the weight of articles and materials of widely different
specific gravity and bulk, such as timber, loaded waggons, locomotive and other
engines, and other heavy bodies, the apparatus being multiplied, if desired, to suit
the requirements of the case, and the respective bags connected with a guage, or
guages, so that the collective pressures of the plungers may be indicated in one spot,
or otherwise.
In Fig. 4, which represents an hydraulic press or rivetting machine, constructed
according to my invention, a is the cylinder, 6 the piston or plunger, and e the
elastic or yielding fluid tight bag or receptacle. The motor liquid employed is
introduced into the receptacle e through a convenient pipe, (not shewn in the
drawings) connected therewith by a fluid tight joint.
The expansion of the receptacle e, by the pressure of the liquid introduced
therein, forces down the piston or plunger b, which, when the pressure is removed,
may be returned to its original position by any convenient arrangement of springs
or otherwise.
Fig. 5 represents, in vertical section, a bag or receptacle e provided with encircling
metal bands i, which slide freely upon the interior surface of the cylinder. The
object of these bands, as before mentioned, is to permit considerable expansion or
elongation of the bag without risk of the sides of the same binding with the interior
of the cylinder. k is a metal shield, or cover, for protecting the top of the bag, or
that portion which bears against the head of the cylinder, from foreign matters.
Fig. 6 represents, in vertical section, a modified construction of bag or receptacle e,
for the same object as just above described. In this modification the bag is con-
structed in an accordion or bellows like form. is a thin metal protector or
binding, which may if desired be applied around the exterior folds of the receptacle e
to avoid wear at those parts.

page_text: The interior sides of the receptacle e may either correspond in shape to the
exterior, as shewn to the left of the centre line, or be plain as shewn to the right
thereof. The same applies to Fig. 7.
Fig. 7 represents in vertical section a bag or receptacle e having corrugated
sides. is the protecting band and k the top shield or cover.
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
1. In hydrostatic weighing, hydraulic rivetting, and other like machines,
introducing the liquid employed to actuate the guage, or to propel the piston or
plunger, into an elastic or yielding bag or receptacle contained within the cylinder,
in lieu of introducing such liquid into the cylinder direct substantially as and for
the purposes specified.
2. In hydrostatic weighing, hydraulic rivetting, and other like machines, in com-
bination with the cylinder and piston, or plunger, thereof, the elastic or yielding
bag or receptacle (e) substantially as and for the purposes specified.
3. The general construction and arrangement of hydrostatic weighing machine
substantially as herein described, and illustrated in Fige. 1, 2 and 3 of the drawings
annexed.
Dated this 2nd day of December 1801
A. E. ALEXANDER,
Chartered Patent Agent,
19, Southampton Buildings, London, W.C., Agent.