IMPROVEMENTS IN DIRECT-ACTING HYDRAULIC MACHINES FOR RIVETTING
Year: 1880

page_text: LETTERS PATENT to Ralph Hart Tweddell, of Delahay Street, Westminster,
in the County of Middlesex, James Platt and John Fielding, both of the Atlas
Engine Works, Gloucester, in the County of Gloucester, for an Invention of
"IMPROVEMENTS IN DIRECT-ACTING HYDRAULIC MACHINES FOR RIVETTING,
Engine works, Gloucester, in the County of Gloucester, for an invention oL
"IMPROVEMENTS IN DIRECT-ACTING HYDRAULIC MACHINES FOR RIVETTING,
PUNCHING, AND SUCH LIKE OPERATIONS, AND IN APPARATUS FOR ADJUSTING
THEM TO THEIR WORK."
PROVISIONAL SPECIFICATION left by the said Ralph Hart Tweddell, James
Platt, and John Fielding at the Office of the Commissioners of Patents on the
10th November 1880.
RALPH HART TWEDDELL, of Delahay Street, Westminster, in the County of
Middlesex, JAMES PLATT and JOHN FIELDING, both of the Atlas Engine Works,
DIRECT-ACTING
Gloucester, in the County of Gloucester. "IMPROVEMENTS IN
HYDRAULIC MACHINES FOR RIVETTING, PUNCHING, AND SUCH LIKE OPERATIONS,
AND IN APPARATUS FOR ADJUSTING THEM TO THEIR WORK."
Our Invention relates to direct acting hydraulic machines for rivetting, punching,
and such like operations, and to apparatus for adjusting them to their work, the
object of our improvements being to render such apparatus readily applicable to
the various kinds of work which they have to perform, and efficient in the
performance of such work.
In rivetting plates together it is often of advantage to press the plates closely
against each other during the rivetting process. For this purpose we make the
hydraulic plunger, which carries the rivetting tool, with an annular cavity in front
fitted with an annular plunger which carries a tubular pressing tool, this cavity
being in constant communication with the pipe supplying working fluid. In like
manner we fit a tubular pressing tool on an annular plunger working in a cavity
in the hob or head which holds up against the rivetting pressure, this cavity being
also in communication with the pipe supplying working fluid. The rivetting and
the holding up tools pass freely through the central hollows of their respective
pressing tools. The plates to be rivetted together being introduced between the
pressing tools, and the rivet being inserted in its hole, the rivetting plunger is

page_text: caused to advance, carrying with it the one pressing tool which, coming first against
the plates, pushes them against the other pressing tool, and the plates are thus
pressed firmly together, when the rivetting tool advances to complete the rivet.
The fluid pressing on the annular plungers partly flows back to the supply pipe,
while the rivetting plunger of greater area is being advanced. In places where the
rivet can be inserted at the side towards the bob, the pressing tool on that side
may be dispensed with. Also in cases where it is inconvenient to allow space for
the pressing plunger on the hob, the pressing tool may be attached to one arm of a
lever, the other arm of which bears against a plunger working in a hydraulic
cylinder arranged in a more convenient position in or on the hob. In many cases,
as in closing in ends of fire boxes and other plated structures, it is necessary to
rivet in a direction at right angles to the movement of the rivetting plunger. To
provide for such cases we place a cupping die on the top of the hob, and we mount
on the top of the rivetting cylinder a lever carrying the rivetting tool. Wo
connect this lever to a bell crank lever worked by the rivetting plunger, thus
transmitting its action at right angles to the direction of its movement. According
to another method we place between the arms of a portable rivetter a pair of levers
at right angles to these arms, these lovers having at their ends the rivetting tools,
which are closed together by the movement of the arms of the rivetter. For tho
purpose of rivetting a set of rivets arranged circularly and obliquely around a fire
door or other opening we mount a hydraulic rivetter having the axial line of its
tools at the required obliquity on a trunnion through which the working. fluid
passes. By turning the rivetter round on this trunnion we bring its tools to bear
on-rivet after rivet of the circular row. In many cases where space is limited, the
rivetting and holding up tools may be fixed on levers arranged and moved as
described in the Specification of a Patent granted to us on the 6th March 1880,
No. 981, these levers being mounted on a trunnion as above described.
hydraulic rivetters, whether stationary or portable, we effect the back stroke by the
push of a small hydraulic plunger against the main plunger or the moving lever of
the machine.
In
In order to avoid twisting the communicating pipes and to retain the valve
handles in a convenient position, we mount the valve box of the machine on the
stationary bearing of the trunnion, which has passages provided with suitablo
packing for the inflow and outflow of the working fluid. For rivetting a set of
rivets around the end of a cylindrical vessel, as for the angle iron at a boiler.
front, we arrange a hydraulic rivetter in the following manner:-On a strong.
frame adjustable in height we mount a horizontal shaft carrying a radial arm
adjustable in length. To the end of this arm we fix a hydraulic rivetter. By
adjusting the height of the shaft so that its axis coincides with the centre.
of the circular row of rivets, and adjusting the radial arm so that the rivetting
tool coincides with any one rivet of the row, the shaft can be turned round
so as to bring the rivetter opposite to each of the rivets in succession. When
it is required to have the movement of the rivetting plunger in a more or
less inclined direction, the whole rivetter may be supended by a circular arc
having a flange resting on rollers in suspended sheave, so that by moving the
are more or less over the rollers the direction in which the rivetter is suspended is
rendered more or less inclined to the vertical line of suspension. It is of advantage
in this arrangement to provide the pipes for supply and discharge of working fluid
with packed trunnions coinciding with the centre of the suspending arc, so that
these pipes remain stationary whilst the rivetter is turned round them as a centre.
Otherwise the frame of the rivetter may be stationary, the hydraulic cylinder and
the holding up die being fitted to move in circular guides around a common centre.
In order to ensure that the rivetting and holding up dies shall always be directly
opposite to one another we connect arms on the rivetting, cylinder and on the
holder of the die to opposite arms of a lever, these arms being so proportioned
that the rivetting cylinder and the holding up die always move through equal
angles.

page_text: We construct a machine for rivetting rows of rivets along the keel of a vessel or
a girder in the following manner :-On a truck having wheels running along a line
o' rails parallel to the keel or girder.we mount by a vertical shaft or perch-pin a.
horizontal turntable. On this table we place a carriage, on which is pivotted a
beam carrying at one end a hydraulic rivetter, and at the other end a suitable
counterweight. The hydraulic rivetter is jointed to the beam, and has an arın
connected by a link to the carriage on which the beam is mounted, so that if by
moving the beam upwards or downwards the rivetter be raised or lowered it is
made to move parallel to itself, and thus the axis of its cylinder is retained in a
horizontal position. By means of an eccentric in the joint of the parallel motion
link the rivetter can be adjusted a little out of the horizontal line to suit
inequalities in the work. Also the holding up tool is provided with an adjustable
screw so that it can be set up against one side of the work to stendy the rivetter
until its plunger makes its stroke. By means of the beam working on its centre
the rivetter can be raised or lowered, and by moving the beam carriage on the turn
plate it can be advanced or retracted; also by turning the turnplate its direction
can be varied, and by moving the truck along the rail it can be brought to act on
rivet after rivet of tho row.
In employing portable hydraulic rivetters which have to be raised or lowered to
suit the work to which they are applied, "we arrange the supply and discharge
valves for the lifting cylinder in the following manner :-In the centre of the valve
box we fit a sliding bolt with a helical spring drawing it down, and to the upper
end of this bolt we joint a sway beam, the ends of which bear on the stems of the
two valves which are arranged one on each side of the central bolt. To each valve
stem we joint the end of a lever which has a swell or protuberance on its lower
side that bears on a plate on the valve box. The valves being round can be turned
round in their seatings, and the levers jointed to them may therefore be extended
outwards in any convenient direction. By pushing or drawing down the outer
end of either lever it works on its lower protuberance as on a fulcrum, raising the
valve from its seat and bearing upwards one end of the sway beam in opposition to
the spring. Such a valve box is conveniently fitted at the end of a telescopic tube
containing passages for the working fluid, and a plunger acted on by the fluid
pressure for raising or lowering the rivetter to which it is connected.
When flexible tubes are employed for communication of the working fluid we
protect and strengthen these tubes and relieve them from longitudinal strain by
enclosing them within a number of separate sheaths arranged along the tubes at
short distances apart, each of these sheaths having at its ends pivots connected to
those of the next sheath by chain links, the whole thus constituting a lifting chain
enclosing the communicating pipes. In many cases it is desirable to inove a
portable rivetter when it is suspended from a crane over a considerable area without
altering its level. Wo construct a crane for this purpose in the following manner:
To a crane post which can revolve on a vertical axis we joint a jib which can be
raised or lowered, and to the end of this jib we joint another jib of equal length,
from which the rivetter is suspended. On the joint of the latter jib we fix a pulley
We attach tho
or segment of a pulley, to which we attach one end of a chain.
other end of the chain to a pulley or segment of a pulley fixed on the crane post,
this pulley or segment having a radius twice that of the former. According as the
first jib is raised or lowered the outer end of the second jib is moved towards or.
away from the crane post in a straight line, the rivetter suspended from it being
thus moved as required over a horizontal plane. We counterbalance the rivetter
and also the jibs by suitable counterweights, and joint the pipes which convoy the
working fluid so that they follow the movements of the jibs.
We pass the chain carrying the machine and its counterweight around a wheel
provided with teeth or recesses to engage the links of the chain, so that according
to the direction in which this wheel is turned the machine is raised or lowered.
In order to adjust.the machine to the work which it may have to perform, whether
it be suspended from the jib as above described or otherwise, wo mount its fulcrum

page_text: or centre of motion of its arms in a horizontal fork or arm terminating in a trunnion
that works in a bearing in the lower end of an arched arm which has at its upper
end a swivel connecting it to the suspending chain. By this jointing the machine
is free to be turned to any desired attitude, vertically or horizontally, as on a
universal joint.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Ralph Hart Tweddell, James Platt, and John Fielding in the Great
Seal Patent Office on the 7th May 1881.
RALPH HART TWEDDELL, of Delahay Street, Westminster, in the County of
Middlesex, JAMES PLATT and JOHN FIELDING, both of the Atlas Engine Works,
Gloucester, in the County of Gloucester. "IMPROVEMENTS IN DIRECT ACTING
HYDRAULIC MACHINES FOR RIVETTING, PUNCHING, AND SUCH LIKE OPERATIONS,
AND IN APPARATUS FOR ADJUSTING THEM TO THEIR WORK."
Our Invention relates to direct acting hydraulic machines for rivetting, punching,
and such like operations, and to apparatus for adjusting them to their work, the
object of our improvements being to render such apparatus readily applicable to
the various kinds of work which they have to perform, and efficient in the
performance of such work.
In rivetting plates together it is often of advantage to press the plates closely
against each other during the rivetting process. For this purpose we construct the
bydraulic rivetter as shown in the vertical section Fig. 1. A is the plunger which
carries the rivetting tool a. In the front part of the plunger A we fit an annular
plunger B which carries a pressing tool b. The space in which the plunger B works
communicates by a channel b¹ with an annular space around the main plunger A,
which space is always in communication with the supply of working fluid. When
for the purpose of rivetting the pressure is permitted to act on the base of the
plunger A, the plunger advances and the pressing tool b takes a bearing on one of
the plates to be rivetted, squeezing it firmly against the other plate while the
rivetting tool a advances and upsets the rivet. On relieving the pressure on the
base of A, the pressure still acting on its annular area causes the drawback of the
plunger. Instead of employing the pressing tool as above described the hob or
head which holds up against the rivetting pressure may, as shewn in Fig. 2, be in
like manner fitted with an annular plunger B₁ carrying a pressing tool b₁
surrounding the fixed rivetting tool a¹. In cases where it is inconvenient to allow
space for the pressing plunger in the hob, it may be arranged, as shewn by the
dotted lines B, on the back of the hob and connected, us shewn in the part side
elevation Fig. 3, and plan Fig. 4, by side rods and side levers B³ to two sliding
bars B, one on each side of the rivetting tool a', the ends of these bars taking a
bearing against one of the plates to be rivetted and operating in the same manner
as the pressing tool b¹. In many cases, as in closing the ends of fire boxes and

page_text: other plated structures, it is necessary to rivet in a direction at right angles to the
movement of the rivetting plunger. To provide for such cases we adopt the
arrangement shewn in side view partly sectional at Fig. 5, and in plan at Fig. 6.
We place the cupping die a¹ on the top of the hob, and we mount on the top of the
rivetting cylinder a lever C carrying the rivetting tool a. We connect the lever C
by a rod C to a bell crank lever C worked by the rivetting plunger A, thus
transmitting its action at right angles to the direction of its movement. It is
convenient to provide several set of pin holes in the levers C and C2, so that their
leverage can be varied. The small plunger a³, shewn in Fig. 5, is always subject
to the pressure of the working fluid, so that on relieving the pressure on the
rivetting plunger A it is caused by the pressure on a² to make its back stroke.
Fig. 7 is a front view, and Fig. 8 a part plan of an arrangement whereby a portable
rivetter may be applied for rivetting in positions not readily accessible to the tools
of the rivetter itself. In this caso the arms D, D, of the portablo rivetter are
provided with thrust studs d, d, instead of the usual rivetting tools, and these studs
bear against a pair of levers D', D', which carry the rivetting tools a, a¹. The
levers D, D¹, may butt against each other at their fulcrum ends D, or both may
butt against the plate or girder on which the rivetter is operating, as shewn in
Figs. 7 and 8, the fulcra being kept in position by a tie loop D³. For the purpose
of rivetting a set of rivets arranged circularly and obliquely around a fire door or
other opening we arrange a hydraulic rivetter, as shewn partly in section at Fig. 9,
with the axial line of the rivetting tools a, a¹, corresponding with the oblique
direction of the rivets. The rivetter is mounted on a trunnion E, through which
there are passages for the working fluid, and on which as an axis the rivetter is
turned round so as to operate upon the successive rivets of the circle surrounding
it. In many cases where space is limited a rivetter of the kind described in the
Specification of a Patent granted to us on the 6th March 1880, No. 981, may bo
employed in this manner, as shewn in Fig. 10, where a, a', are the rivetting tools
held on bent levers, one of which is moved for rivetting by the curved plunger A,
and retracted by the small plunger a³; the other lover has a tubular axis or
trunnion E, through which there is passage for the working fluid, and round which
the rivetter is turned to operate on the successive circularly arranged rivets. In
other forms of rivetters, beside those above described, we effect the back stroke by
the pull or push of a small hydraulic piston or plunger a against the main plunger.
For example, in a rivetter of the form shewn in longitudinal section at Fig. 11, and
end view at Fig. 12, in which the rivetting tools a, a, are at the side of the main
plunger A, a small piston a², which is always subject to the pressure of the
working fluid, draws back the main plunger A when it is relieved from pressure.
For rivetting a set of rivets around the end of a cylindrical vessel, as for the.
angle iron at a boiler front, we arrange a bydraulic rivetter as shown at Fig. 13.
On a strong frame F which can be adjusted in height by means of a rack and
pinion worked by worm gear F¹, we mount a horizontal shaft F2 carrying a radial
arm F3 adjustable in length in a similar manner, or by means of a screw applied as
in a slide rest. To the end of this arm we fix the bydraulic rivetter G, for which
we provide a suitable counter-balance G' fixed opposite to the rivetter on shaft F
By means of a worm engaging with a stationary worm wheel F, the shaft Fª with
its arm and rivetter can be turned round so as to bring the rivetting tools to act on
the successive rivets. The working fluid passes through a bore hole in the shaft F
and thence by flexible or jointed pipes along the arm F to the valve box Gª of the
rivetter. By suitably adjusting the height of the axis F2, and the length of the
arm F3 the rivetter can be made to operate on circular flanges of various diameters
within the limits for which the apparatus is adapted. When it is required to have
the movement of the rivetting plunger in a more or less inclined direction, as for
rivetting a flange on to a cylindrical boiler, wo suspend the rivetter in the manner
shown in Fig. 14. To the rivetter G we attach a circular are H having a flango
resting on rollers h, h, mounted in a suspending block H, and by means of a
pinion mounted in the block H₁, and gearing with teeth on the arc H we

page_text: move the arc so as to turn the rivetter into a more or less inclined attitude, as
indicated by the dotted lines. Instead of thus moving the whole rivetter, the
direction of the cylinder and rivetting tools may be varied as shewn in Fig. 15. In
this case the cylinder K with its plunger A and rivetting tool a is fitted to slide
along a circular guide arc K¹ at the end of one arm of the rivetter frame, and the
holling up tool a¹ is fixed on a circular slide fitted to work on guides K at the end
of the other arm of the rivetter frame. The guide arcs K' and K2 are both struck
from the same centre, which is about the middle of the rivet, and arms K³, K*, pro-
jecting respectively from the cylinder and from the slide of the bolding up tool, are
connected by rods K³, Ko, to opposite arms of a lever K7, so that when tho
direction of the cylinder and rivetting tool is varied that of the holding up tool
is varied to correspond therewith, both being caused to move through equal angles.
A portable rivetter may be mounted so as to accommodate itself to various directions
of action both in the horizontal and in the vertical plane, in the manner shewn in
side view at Fig. 16, in front view at Fig. 17, and in back view at Fig. 18. The
rivetter G which, as shewn in these Figures, may be of the kind described in our
Specification No. 981 of 1880, above referred to, or of other known kind, is pivotted
at G' on a bent arin L, which at L' is pivotted on another bent arm L², and this is
swivelled at L³ to the suspending block or hook. By turning the apparatus round
the axis L³ in the horizontal plane, round the axis L' in one vertical plane, and
round the axis G₁ in another vertical plane at right angles to the former, the
direction of rivetting may be varied as desired. In some cases it is convenient to
suspend the rivetter in the manner shewn in Fig. 19, by taking hold of a lever M,
one end of which is pivotted at M' to the frame of the rivetter and the other end is
jointed to the rivetting ram or the holder of its tool a.
We construct a machine for rivetting rows of rivets along the keel of a vessel or
a girder, as shewn in elevation at Fig. 20, and in plan at Fig. 21. On a truck N
having wheels N' running along rails parallel to the keel or girder we mount by a
vertical shaft or perch più N' a horizontal turn table N³. On this table we place a
carriage N, on which is pivotted a beam N' carrying at one end a hydraulic
rivetter G, and at the other end a suitable counterbalance G'. The rivetter is
jointed at n to the beam No, and its arm at n¹ is connected by a link n³ to a pin n³
on the carriage N*, so that when by moving by means of a handle n' the beam N³
upwards or downwards, the rivetter G is raised or lowered, it is made to move
parallel to itself, and thus the axis of the cylinder is retained in a horizontal
position. By means of an eccentric pin at the joint n', as shewn to an enlarged
scale at Fig. 22, the rivetter G can be adjusted a little out of the horizontal line to
suit inequalities of the work. The holding up tool a' is provided with an
adjustable screw a², so that it can be set up against one side of the keel or girder to
steady the rivetter until its plunger A makes its stroke. By means of the pivotted
benin N the rivetter can be raised or lowered, by moving the carriage N* along the
turnplate it can be advanced or retracted, by turning the turnplate round its
vertical axis Nº the direction of the rivetter may be varied, and by moving the
truck N along the rails the rivetter can be brought to act on the successive rivets
of the row.
In employing portable hydraulic rivetters which have to be raised or lowered to
suit the work to which they are applied, we arrange tho supply and discharge
valves for the lifting cylinder or telescopic tube, as we will describe referring to
Figs. 23 to 27 inclusive; Fig. 23 is a vertical section through the valve box;
Fig. 24 is a transverse section through one of the valves and its passage; Fig. 25 is
a plan of the valve box, shewing the telescopic tube or lifting cylinder in section;
Fig. 20 is a sectional plan of the valve box; and Fig. 27 is a vertical section on a
reduced scale of the telescopic tube with the valve box attached thereto. In the
centre of the valve box we fit a sliding bolt P with a helical spring drawing it
down, and to the upper end of this bolt we joint a sway beam P', the ends of which
bear on the stems of the valves p', p², which are arranged one on each side of the
central bolt P. To cach valve stem wo joint the end of a lever p³, p', which has a

page_text: swell or protuberance on its lower side that bears on a plate on the valve box.
Tho valves being round can be turned round in their seatings, and the levers p³, p*,
jointed to them may therefore extend outwards from them in any convenient
direction. By pushing or drawing down the outer end of either lever, such as p¹,
it works on its lower protuberance as on a fulcrum, raising the valve p from its
seat and bearing up one end of the sway! beam P¹ in opposition to the spring,
The telescopic tube, to the lower end of which the valve box is attached, as shown
in Fig. 27, contains passages for the working fluid, and a plunger acted on by the
fluid pressure for raising or lowering the rivetter suspended from the valve box.
The outer tube Q, which is suspended by a crane or otherwise, forms a cylinder in
which works the piston Q. This piston has a tubular stem Q, which works
through packing at the bottom of the tube and is attached to the valve box. The
stem Q is a double tube, having within it an annular space communicating by
passages at the bottom with the two valves p', p, as shewn in Fig. 25, and having
at its upper end lateral apertures opening into the annular space between Q and Q².
Within the tube Q2 is an inner tube Q3, which is open at the bottom, and is at the
top attached to the head that carries the tube passing through packing in the
piston Q. When one of the valves p', p², is opened, fluid under pressure enters
the tube Q, and acting on the piston Q' causes it to ascend, raising the rivetter
attached to it. When the other valve is opened the piston Q¹ is relieved from
pressure and it descends lowering the rivetter.
When flexible tubes are employed for communication of the working fluid we
protect and strengthen these tubes and relieve them from longitudinal strain by
enclosing them within a number of separate sheaths, arranged along the tubes at
short distances apart, each of these sheaths having at its ends pivots connected to
those of the next sheath by chain links, the whole thus constituting a lifting chain
enclosing the communicating pipes. This construction is shewn in side view at
Fig. 28, and vertical section at Fig. 29, where R is the flexible tube, S, S, the short
sheaths enclosing portions of it at intervals, these sheaths having end pivots
connected by links T. Fig. 30 is a similar arrangement for two tubes R, R. In
many cases it is desirable to move a portable rivetter when it is suspended from a
We construct a crane
crane over a considerable area without altering its level.
for this purpose as shewn in Fig. 31. To a crane post U which can revolve on a
vertical axis we joint a jib V, which can be raised or lowered, and to the end of
this jib we joint another jib V₁ of equal length, from which the rivetter G is
suspended. On the second jib V', at its joint, wo fix a pulley or segment of a
pulley V2, to which we attach one end of a chain Vs. We attach the other end
of the chain V3 to a pulley or segment of a pulley V fixed on the crane post U,
this pulley or segment V* having twice the radius of V. According as the first
jib V is raised or lowered, the outer end of the second jib V₁ is moved towards or
away from the crane post in a straight line, as indicated by the dotted lines, the
rivetter G suspended froin it being thus moved, as required, over a horizontal plane.
We counterbalance the rivetter by a weight W, and also the jibs by suitable
counterweights, as V, and we joint the pipes R which convey the working fluid so
that they follow the movements of the jibs. For raising or lowering the rivetter
we pass its suspending chain round a chain pulley X having teeth or recesses to
engage the links of the chain, and turning this pulley by worm gearing ✗'
we raise or lower the rivetter G, its counterweight W being lowered or raised in a
corresponding manner. The rivetter G inay be suspended directly from the axis of
the pulley ✗, or, when it is desired to turn it to various angles, it may be suspended
by a yoke Y swivelled at the top, and having a trunnion or pivot Z by which it is
jointed to the rivetter. Also the arrangements for suspension, above described
with reference to Figs. 14 to 19 inclusive, may obviously be employed.
Although in what precedes we have treated the hydraulic machines referred to
5 as if they were for rivetting only, it is to be understood that similar machines for
such operations as punching, shearing, stamping, and the like, may be dealt with

page_text: in the same manner as the hydraulic rivetters, to which our description has been
principally directed.
Having thus described the nature of the said Invention, and in what manner the
samo is to be performed, we claim as improvements in direct acting hydraulic
machines for rivetting, punching, and such like operations, and in apparatus for
adjusting them to their work,
First. For pressing together plates while they are rivetted, the use of pressing
tools in the rivetting head or in the hob, the said pressing tools being worked by a
hydraulic plunger which is always subject to the pressure of the working fluid, as
herein described with reference to Figs. 1, 2, 3, and 4.
Second. For rivetting in a direction at right angles to that in which the rivetting
plunger moves, the combination of the levers C, C³, and link C', with the rivetter,
as described with reference to Figs. 5 and 6.
Third. For rivetting around the the end of a boiler or other circular vessel,
mounting the rivetter, as described with reference to Fig. 13.
Fourth. Suspending the rivetter so that it can be turned round in a horizontal
plane and also in two vertical planes at right angles to each other, as described
with reference to Figs. 16, 17, and 18.
Fifth. The arrangement of telescope tube for raising or lowering the rivetter in
combination with valves and levers, as described with reference to Figs 23, 24, 25,
26, and 27.
Sixth. For strengthening and supporting the flexible tube conveying working
fluid, and for relieving it from tensile strain, the use of sheaths linked together so
as to constitute a chain, as described with reference to Figs. 28, 29, and 30.
Seventh. For suspending the rivetter so that it can be moved over a horizontal
plane, the use of the crane arrangement, described with reference to Fig. 31.
In witness whereof, I, the said Ralph Hart Tweddell, on behalf of myself
and the said James Platt and John Fielding, have hereunto set my hand
and seal, this Sixth day of May, in the year of our Lord One thousand
eight hundred and eighty one.