Cranes, Hoists, and other like Machinery.
Year: 1885

page_text: Cranes, Hoists, and other like Machinery.
I JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention which has been com-
municated to me from abroad by Eusebe Victor Vincent de Paul Desdouits of
Tours in the Republic of France Engineer to be as follows:-
This Invention relates to improved apparatus for regulating and controlling the
speed of lifting or hoisting machinery being also applicable to regulating and
controlling the speed of other machinery working under analogous conditions.
According to this Invention a massive break disc is placed on a screw of rapid
pitch forming a prolongation of one of the shafts of the machine whose speed is to
be regulated and controlled. This disc when turned in one direction upon the
screw as hereinafter explained is jammed against the side of the bearing or support
in such a manner as to retard or arrest the notion of the shaft.
Suitable springs are employed to maintain the disc out of contact with the
bearing when the retarding action is not required. So long as the machine runs
regularly or at its normal speed the disc turns with the shaft without shifting to
the right or to the left upon the screw but whenever the speed is suddenly
accelerated the disc owing to its inertia rotates less rapidly than the shaft and
becoming screwed up against the side of the bearing automatically retards the
motion.
Directly the motion of the screwed shaft is slowed the action is reversed and the
disc returns to its original position.
The action of the break disc may be controlled by a nut bearing against a spring
and working on a screw attached to the end of a lever suspended from a bracket or
arm and acting on a plate or disc connected to the break disc but of somewhat
smaller diameter than the latter.

page_text: By means of this arrangement the retarding action of the break disc may be
counterbalanced to an adjustable extent by regulating the pressure and friction of
the lever upon the aforesaid plate by means of the nut and spring so as to obtain a
uniform speed.
According to another arrangement the break disc is provided with a collar or
flange which engages with a corresponding internal flange formed on a species of
clutch box working on a fixed screw. A lever fixed on the box enables the latter
to be turned upon the screw so as to bring its flange in contact with the flange on
the break disc and move the latter away from the wearing or friction surface on
the support. The break disc continuing to rotate with the shaft and the friction
between the two flanges being less than that on the support the motion is rendered
uniform and regular.
°

page_text: Cranes, Hoists, and other like Machinery.
I JOHN HENRY JOHNSON of 47 Lincoln's Inn Fields in the County of Middlesex
Gentleman do hereby declare the nature of this Invention which has been com-
municated to me from abroad by Eusebe Victor Vincent de Paul Desdouits of
Tours in the Republic of France Engineer 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 improved apparatus for regulating and controlling the
speed of lifting or hoisting machinery being also applicable to regulating and
controlling the speed of other machinery working under analogous conditions.
According to this Invention the principal shaft of the hoisting machine or one of
the auxiliary shafts is provided with a quick threaded screw and on this screw is
fitted a disc or nut of suitable weight and diameter as to be susceptible of
tightening or jamming itself against a fixed part of the machine in order to control
the winding and retain or sustain the weight. It is not necessary to use force to
screw up the nut or disc the tightening or screwing up being effected by the action
of the weight provided the nut or disc has a diameter three or four times that of
the screw A disc or nut with a conical or wedge shaped friction surface may be
employed and in this case the diameter of the disc can be diminished-If the
weight carried by the machine is descending too rapidly, for example, so that the
shaft is turned round with excessive speed the disc or nut owing to its inertia
rotates at first less rapidly than the shaft and consequently by the action of the
screw thread screws up against a fixed portion of the machine and thus retards or.
stops the descent of the weight-At whatever speed the weight is being hoisted.
the disc brake is free and exercises no friction whatever. In lowering the weight
the disc brake also turns freely so long as the motion is maintained uniform. In
case the descending movement is not perfectly regular a spiral or other spring may
be employed to keep the disc free and in this case as in the hoisting movement if
the governing or retaining power is removed the brake comes into action instantly.
A rapid descent can be obtained by combining the movement of this disc brake
with that of the ordinary lever friction brake. It is sufficient that the disc be.
separated from the upright plate or fixed bearing surface at the same time as the
application of the ordinary-regulating brake. This separating or detaching move-
ment may be obtained either by a small spring or by other means for instance by
means of a cord or chain attached to the controlling lever of the ordinary brake.
A very sensitive or rapidly acting apparatus may be obtained by applying on
the outside circumference of the disc a light pressure produced by a weight or
spring as hereinafter explained.
And in order that my said Invention may be fully understood I shall now
proceed more particularly to describe the same and for that purpose shall refer to
the soveral figures on the annexed sheet of drawings the same letters of reference
indicating corresponding parts in all the figures.

page_text: Figure 1 of the accompanying drawings represents a vertical section of an
apparatus constructed according to this Invention and figures 2 and 3 represent
respectively a transverse section and side elevation of a modified form of the said
apparatus as hereinafter explained.
A, Figure 1 represents a shaft working in a bearing D and forming part of the
hoisting mechanism. This shaft is provided with a prolongation B in the form of
a screw with a rapid pitch working in a female screw formed in a disc C. The
disc C is of such weight that its vis inertia prevents it from immediately sharing or
partaking of sudden changes in the rate of revolution of the shaft A and screw B.
A spring or springs a may be placed under the disc C. in order to maintain it
normally out of contact with the side of the bearing D.
So long as the machine runs regularly or at its normal speed with a uniform
motion the disc C. turns with the shaft A without shifting to the right or to the
left upon the screw B but whenever the speed is suddenly accelerated from any
cause the disc C. owing to its inertia rotates less rapidly than the shaft A and
travels axially along the screw B in such a manner as to jam against the bearing D
and automatically retard or arrest the motion of the machine.
According to the arrangement illustrated in figures 2 and 3 the action of the
disc C. is controlled by a lever F connected with a spring or provided with a
counterweight G and bearing on the periphery E of the disc C. at F1 with the
object of rendering the automatic brake more sensitive and rapid in its action and
at the same time enabling its action to be controlled by means of a cord I attached
to the lever F and to the disc C. In this arrangement the automatic brake is
advantageously combined with an ordinary brake strap K operated by the lever F
being so arranged that when the cord I is pulled in the direction of the arrow the
ordinary brake strap K is applied and the automatic brake is at the same time
taken off.
All the arrangements herein before described for raising lowering or sustaining
weights may be employed for maintaining the tension of wires in combination
with apparatus for drawing up or tightening wires or wire cables for example.
Having now particularly described and ascertained the nature of the said
Invention and in what manner the same is to be performed I declare that what
I claim is,
al
1st. In an apparatus or means for automatically regulating and controlling the
speed of cranes hoists and other like machinery a disc or the like working freely
upon a screw rotating with the machine whose speed is to be regulated or con-
trolled the said disc possessing sufficient vis inertia to prevent it from partaking
of sudden accessions of speed of the screw and being so arranged that when the
screw rotates too rapidly the disc travels along the screw and jams against
stationary bearing so as to retard or arrest the motion of the machine substantially
as herein before described with reference to figure 1 of the accompanying drawings.
2nd. The combination with the subject matter of the preceding claiming clause
of means for controlling the action of the screwed disc in combination or not with
an ordinary brake strap substantially as herein before described with reference to
Figures 2 and 3 of the accompanying drawings.
Dated this 23rd day of Sontember 188ec