IMPROVEMENTS IN STEAM HOISTS
Year: 1880

page_text: LETTERS PATENT to Thomas Archer, junior, of Dunston Engine Works, in the
Town of Gateshead and County of Durham, Engineer, for an Invention of
IMPROVEMENTS IN STEAM HOISTS."
"
PROVISIONAL SPECIFICATION left by the said Thomas Archer, junior, at
the Office of the Commissioners of Patents on the 5th November 1880.
THOMAS ARCHER, junior, of Dunston Engine Works, in the Town of
Gateshead and County of Durham, Engineer. "IMPROVEMENTS IN STEAM
HOISTS."
My improvements in steam hoists apply to that description of hoist in which a
long cylinder and piston with flexible piston rod are used. Instead of employing
a case in communication with the interior of the cylinder in which the flexible rod
is coiled, as described in Specification of my Patent, No. 3802, 1879, and which
causes a considerable loss of cushion steam and difficulty of inspection of and access
to the rod, I employ a mere covering for the rod, and pass it through a stuffing
box nearly or quite steam tight on the cylinder cover. I prefer to employ for the
rod a ribbon band of steel or other suitable material, with guide roller or rollers for
the band to pass over so as to give it all times uniform direction of movement
without side pressure on the gland. I attach the ribbon rod to the piston at one
end, and at the other end attach it to and coil it on a drum mounted on a shaft,
on which shaft but on another drum the chain or rope for hoisting is also coiled the
reverse way, the relative diameters of the drums (subject to modifications expressed
afterwards) being such as to give the full lift required at the full stroke of the
piston. I also employ buffer springs at each end of the cylinder to prevent injury
in case of slip or breakage of chain or carlessness in handling, and an internally
opening spring valve to prevent injury to the ribbon rod from vacuum. I also
employ when required an automatic shut off apparatus for the steam with
regulators to bring it into action in different degrees as may be desired; and I
also employ when required an automatic brake with similar regulating gear_to
bring it into action at any desired point of the stroke. I use the exhaust steam
or its first effect, and by itself or aided by fresh steam or hand power, for
when required the weight lifted while it is held up by a brake. I also employ an
arrangement to alter the diameter of one or both of the drums in accordance with
the weights to be lifted or for variation in the height of the lift.
$

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Archer, junior, in the Great Seal Patent Office on the 5th
May 1881.
THOMAS ARCHER, junior, of Dunston Engine Works, Gateshead, in the County
of Durham, Engineer. "IMPROVEMENTS IN STEAM HOISTS."
My improvements in steam hoists apply to that description of hoist in which a
long cylinder and piston with flexible piston rod are used. Instead of employing a
case in communication with the interior of the cylinder in which the flexible rod is
coiled, as described in Specification of my Patent, No. 3802, 1879, and which causes
a considerable loss of cushion steam and difficulty of inspection of and access to the
rod, I employ a mere covering for the rod and pass it through a stuffing box
nearly or quite steam tight on the cylinder cover. I prefer to employ for the rod
a ribbon band of steel or other suitable material with guide roller or rollers for the
band to pass over so as to give it at all times uniform direction of movement
without side pressure on the gland. I attach the ribbon rod to the piston at one
end, and at the other end attach it to and coil it on a drum mounted on a shaft,
on which shaft but on another drum the chain or rope for hoisting is also coiled the
reverse way, the relative diameters of the drums (subject to modifications expressed
afterwards) being such as to give the full lift required at the full stroke of the
piston. I also employ buffer springs at each end of the cylinder to prevent injury
in case of slip or breakage of chain or carelessness in handling, and an internally
opening spring valve to prevent injury to the ribbon rod from vacuum. I also
employ when required an automatic shut off apparatus for the steam with regulator
to bring it into action in different degrees, as may be desired; and I also employ
when required an automatic brake with similar regulating gear to bring it into
action at any desired point of the stroke. I use the exhaust steam or its first effect,
and by itself or aided by fresh steam or hand power, for shewing when required
the weight lifted while it is held up by a brake. I also employ an arrangement
to alter the diameter of one or both of the drums in accordance with the weights to
be lifted or for variation in the height of the lift.
Having thus described the nature of my Invention, I will proceed more particu-
larly to describe the manner in which the same is to be operated, reference being
had to the Drawings hereto attached.
Fig. 1 is a section of an apparatus according to my Invention, and Fig. 2 an
external view as seen from one side of the view in Fig. 1. Fig. 3 is intended to
illustrate the method already referred to of altering the diameter of the drum or
drums employed. The same letters refer to similar parts in each Drawing.
In Fig. 1 A is the steam cylinder, B is the piston, and C the ribbon rod attached
to the piston and also to the drum E by the attachment shewn at F. D is a gland,
which for convenience I prefer to make in halves fitting in a stuffing box with
packing in the usual way so as to be nearly or quite steam tight. I make the
ribbon rod of steel, phosphor bronze, or other suitable material, so thin in one
direction as to coil without inconvenience on the drum E, and so wide in the other
direction as to bear the requisite strain due to the steam pressure and load lifted.
G, G, is a cover or guard plate intended to protect the ribbon rod from injury, or
should the band chance to break to prevent its flying quite loose so as to do injury.
H is a brake handle operating a brake of any ordinary construction, and which it
is therefore not necessary to describe. J is the lifting drum, on which a chain is
coiled the reverse way to the ribbon rod on E. K is the steam cock made with
double ports, so as that in accordance with the position of the handle it will either
admit steam or open to the exhaust. The steam and exhaust pipes are shown in
Fig. 2, marked L and M respectively. It will be manifest that if the piston be at
the top of the cylinder and the ribbon rod coiled on the drum E and the lifting

page_text: chain attached to the drum J in the opposite direction, as these two drums are
keyed firmly on one shaft, the tendency of the steam pressure will be to lift the
chain and any weight attached to it, and this in fact is the manner in which my
apparatus operates. I have found however that inconvenience arises from careless
handling or accident to the rod unless buffer springs are applied, as at S, S, to
take up the impetus of the piston should it from any cause run amain, and an
important part of my Invention is the use of these buffer springs. I have also
found that inconvenience arises in the event of the weight being lifted and held by
the brake for any considerable time or quickly and at lengthened intervals from
the condensation of steam in the cylinder, which causes the return of the piston
due to the partial vacuum formed, and which breaks or distorts the ribbon rod;
and an important part of my Invention is the introduction of an internally opening
automatic valve which allows the entrance of air into the cylinder when the
pressure within it falls below atmospheric pressure. I also attach to the drum an
arrangement, not shewn in my Drawing, so as to avoid complication, and because it
is a well understood description of mechanism applied to steam hammers and to
winding apparatus, and the application of which only to this description of hoist is
my Invention, which apparatus automatically shuts off the steam at the full or any
desired part of the stroke, and which also automatically applies the holding brake
at any desired part of the stroke. I have also omitted to shew in my Drawing
what I consider an important part of my Invention, namely, the slewing arrange-
ment by exhaust steam or partly exhaust and partly fresh steam, and I omit this
Drawing because there are so many different applications of it, and its action is not
new, but, on the contrary, well understood, my Invention being its application only
to these particular description of hoists. I do not claim either the use of expanding
drum, which are well known mechanism, excepting so far as regards their applica-
tion to these particular description of hoist when it may be desirable to vary the
lift and the load. Fig. 3 illustrates the method I prefer to employ of making the
expanding drum, but this, as I have said, illustrates only my preference, and I do
not describe it, as it is no part of my Invention.
Having thus described and explained the operation of my Invention, I claim
the combination of all or any of the following with hoisting apparatus such as I
have described, namely, the buffer springs, the internal opening valve, the applica-
tion of the automatic cut off and brake arrangement, the application of slewing
arrangements, and the use of expanding drums. And I claim as my Invention also
the use of ribbon rod passing through a stuffing box steam tight and coiling.on a
drum in the open air so as to avoid cushion space and loss of steam, and to enable
the condition of the ribbon rod to be easily ascertained without taking the
apparatus to pieces.
In witness whereof, I, the said Thomas Archer, junior, have hereunto set my
hand and seal, this Third day of May, in the year of our Lord One thousand
Witness to the signature of
Thomas Archer, junior,
JOHN BOWMER,
Clerk,
Forest Hall,
N Newcastle.
THOMAS ARCHER, JR. (L.S.)