Improvements in Indicators for Fluid-pressure Engines.
Year: 1889

page_text: Date of Application, 10th Oct., 1889
Complete Specification Left, 9th July, 1890-Accepted, 4th Oct., 1890
PROVISIONAL SPECIFICATION.
Improvements in Indicators for Fluid-pressure Engines.
I, EBENEZER HALL-BROWN, of 15 Moor Terrace, Hartlepool, in the County of
Durham, Engineer, do hereby declare the nature of this invention to be as follows:-
My improved indicator for fluid pressure engines consists of:-
A cylinder with a piston and spring of a form similar to that ordinarily used in a
"Richard's" indicator or of other suitable form.
A cylinder or drum for holding the paper upon which the diagram is traced, carried
by a bracket or horizontal projection from the aforesaid cylinder, and capable of
limited rotary motion, such motion being usually transmitted from some moving part
of the engine to be indicated by means of a cord.
A special form of parallel motion or pantograph consisting of two links and two
levers of the third class, or of one link two levers of the third class, and a curved slot
or guide, suitably connected to the piston-rod head. The pencil or marker for tracing
the indicator diagram is carried by the parallel motion or pantograph in such a
manner that it moves approximately in a straight line. The said parallel motion or
pantograph is mounted upon the cylinder cover or cap in such a manner as to be
capable of partial rotary motion about the axis of the cylinder.
A new or improved means of securing or fastening the aforesaid cylinder cover or
cap upon which the parallel motion or pantograph is mounted, to the cylinder, so
that a slight motion of a handle or partial revolution of the cylinder cover or cap
serves to release the said cover or cap with all attachments from the cylinder or to
secure them to the cylinder.
The whole forms an improved indicator specially suitable for work in which it is
requisite that indicator diagrams should be taken within a limited time as the peculiar
formation of the indicator renders it possible to remove the whole of the working
parts from the cylinder and to replace them in a very short time.
Dated this Ninth day of October 1889.
E. HALL-BROWN.
COMPLETE SPECIFICATION.
Improvements in Indicators for Fluid-pressure Engines.
I, EBENEZER HALL-BROWN 15 Moor Terrace Hartlepool in the County of Durham
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 a special construction of indicators for fluid pressure
engines and consists in providing a suitable cylinder within which a piston connected
with a spring works the said piston being suitably connected to a special form of
parallel motion or pautograph which causes a marker to register the indications on
a card or sheet of paper which is carried upon a suitable barrel.
The invention also includes an improved method of securing the cylinder cap but
although I prefer the improved method shown, I may if desired use any ordinary
method.
1
In order that this invention may be fully understood I annex drawings to which I
now refer.
Fig. 1 shows elevation partly in section of this improved indicator for fluid pressure
engines.

page_text: 1 is the indicator cylinder enclosing the piston. 2 the indicator piston. 2b the
indicator spring. 3 is the drum for receiving the paper on which the indications or
diagrams are to be traced. 4 a bracket or arin or other support for drum 3.
The pantograph or parallel motion is formed by the following parts 5 and 6 are
two links connecting the piston rod head 2ª to the two levers of the third class 7
and 8. The lever 7 is jointed to the motion plate 10 at 7. By having these levers
and links suitably proportioned the marker 9 may be caused to move in an approxi-
mately straight line and at a practically constant ratio to the motion of the piston rod
head 2ª. The motion plate 10 which carries the joint 7° and by means of which the
parallel motion or pantograph is capable of limited rotary motion about the axis of
the cylinder 1 is mounted upon the cylinder cover 11 and secured by means of the
plate which is held in place by one or more screws or other suitable device. The
cylinder cap 11 is secured to the cylinder I by means of pins 16 and 17 and
the circular catch 15. This circular catch is held in place by motion plate 10.
Fig. 3 shows a modified form of connecting the piston head to the indicator marker
in which case the links and 6 are connected to the piston head 2ª by means of a
single pin on the centre line of the piston rod instead of two pins.
Fig. 4 shows a further modification, the link 5 being replaced by the curved slot or
guide 18 formed upon the piston rod head 2ª the link 6 being connected to the piston
rod head 2 by a pin as in Fig. 1.
Fig. 5 shows a still further modification the link 5 being replaced by the curved
slot or guide 18 as in Fig. 4 but the link 6 being connected to the piston rod head by
means of a pin in the centre line of the piston rod as in Fig. 3.
Figs. 6 to 14 inclusive shew details of a method of securing the cylinder cap 11 to
the cylinder 1.
Fig. 6 shews an outside view of the upper part of the cylinder 1 with bracket or
support 4 for holding the diagram drum. 16 and 17 are two pins for securing the
cylinder cover or cap.
Fig. 7 is a plan of Fig. 6.
Fig. 8 is a sectional elevation of the part of the cylinder 1 with cover 11 and
circular catch 15.
Fig. 9 is a sectional plan of Fig. 8 through a. y. shewing the handle 13 for holding
and tightening the cylinder cap 11 and all its connections and for conveniently
removing the same from the cylinder, and the handle 14 for moving the circular
catch 15.
Fig. 10 shews an expanded view of slot in the circular catch 15.
Fig. 11 shews an expanded view of slot in the cylinder cover or cap 11. the lower
side of this slot tapers or forms part of a helix so that when the cover is revolved there
is a wedge like action which holds the cylinder cap firmly down.
Fig. 12 shews the relative position of the cover or cap 11, the catch plate 15, and
one of the pius 16, when the cover is firmly secured.
Fig. 13 shews the relative position of these parts, when the cover is being removed
from the cylinder, or being placed thereon. The method of placing and fixing the
cylinder cap on the cylinder, is as follows. The circular catch 15 is moved into
position shewn in Fig. 13; the cap is then lifted by the handle 13 and placed upon
the cylinder, care being taken that the pins 16 and 17 enter the slots, when the cap
has been pushed down, so that the pins are at the top of the slots, as in Fig. 13 the
handle 13 is turned so as to bring the pins well up the tapered slot, when this is
being done, the pins 16 and 17. come against the end of the slots in the circular
catch 15, and prevent it revolving with the cylinder cover or cap, so that the cover or
cap is firmly secured in the position shewn in Fig. 12. To remove the cap it is
necessary to pull the handle 13 in the opposite direction to that required in fastening
it, and also to pull the handle 14 of the circular catch into the position shewn in
Fig. 13.
Fig. 14 is an external elevation of the cylinder cover 11 with catch 15, and.
handles 13 & 14.
Fig. 1 shews a sectional elevation and Fig. 16 a plan of a modified form of fixing

page_text: the cylinder cap in which case the handle 13 is hinged to the cover 11 by the pin or
joint 19 and has formed upon it the projection 21, which locks with a suitably placed
pin 20. To release cover or cap it is necessary to lift the handle 13, until the pro-
jection 21 clears the pin 20. The slots in the cover 11 are of the shape shewn in
Fig. 11.
Fig. 17 shews a sectional plan of another method of fastening the cylinder cap 11.
In this case the cover or cap is prevented from being accidentally released by means
of a pawl or catch 22 which is hinged at 24, and held in position by spring 23.
Fig. 18 shews sectional elevation and Fig. 19 a sectional plan of a modification of
the arrangement. In this case the handle 13 is omitted and the cylinder cover or
cap 11 is revolved for the purpose of which notches 27 and 28 are provided.
Fig. 20 shews a sectional elevation & Fig. 21 a sectional plan of a modification of
the arrangement shewn in Figures 6 to 14 inclusive. In this case the cover 11 is not
revolved but only the circular catch 15, the forms of slots in the catch are as shewn
in Fig. 22. In this case the bottom side of the slot in the circular catch plate tapers
or is of the form of a part of a helix and this acts to secure the cap firmly to the
cylinder. The handle 14 being short is not apt to be moved accidentally.
Figs. 23 and 24 shews another modification to take the place of the pins 16 and 17.
In Fig. 23 projections are formed either of the solid metal of the cylinder or are
secured thereto in a suitable manner.
Fig. 25 shews a form of cylinder cover or cap 11 suitable for use with a deep
motion plate 10. In this case the motion plate is held in position by the plate or
cap 12 which is screwed into the part 11.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed what I claim and desire to
secure by Letters Patent is
(1) The arrangement and combination of the parts forming the improved indicator
substantially as described in this specification and shown in the annexed drawings and
for the purpose set forth.
(2) The arrangement of parallel motion or pantograph substantially as described
herein and shown in Figures 1, 2, 3, 4 and 5 and for the purpose set forth.
(3) The method of and arrangement for securing or releasing the cylinder cover
and cap as shewn in Figures 6 to 22 inclusive and substantially as described and for
the purpose set forth.
(4) The several arrangements for securing the cylinder cover as described, in com-
bination with the projecting pieces as shown in Figure 23, in place of pins, substantially
as described and for the purpose set forth.
(5) The arrangement of the cylinder cap as shewn in Figure 25, substantially as
described and for the purpose set forth.
(6) The several methods of and arrangements for fastening and releasing the
cylinder cap or cover of an indicator for fluid pressure engines substantially as
described and for the purpose set forth.
Dated this 9th day of July 1890
EDMUND EATON,
Consulting Engineer & Patent Agent, Agent for Applicant.