SAFETY DEVICES FOR ELEVATORS
Year: 1884

page_text: I, RUDOLPH C. SMITH Civil Engineer Yonkers, Westchester County N. Y.
do hereby declare the nature of said invention for " SAFETY DEVICES FOR
ELEVATORS" to be as follows:-
:-
This invention relates to Improvements in Safety Devices for Elevators, and
consists in the combination with the elevator cage and certain upright bars or
guides, of devices for creating a determined and regulated frictional resistance, and
means for putting them in operation upon the too rapid descent of the cage, so as
to retard or arrest the downward movement.
One of the different modes of carrying out the principal of the invention may
be described as follows:-
The cage or platform is of. any suitable construction and is combined with any
of the usual elevating mechanism, whereby it is moved vertically within the well.
At opposite sides of the cage are stationary parallel bars which may constitute or
supplement the usual vertical guide bars and beneath the cage extends a cross bar
or beam having notches at the ends to receive said bars. One side of each notch
presents a face parallel to the face of the adjacent bar the other side of said notch
is inclined and at such a distance from the face of the guide, as to permit the
introduction.of a wedge, the vertical face of which is opposite the face of the guide
while the angle. of the opposite face corresponds to that of the inclined face before
mentioned. A lip or other suitable stop upon each wedge permits the limited
downward movement of the latter, with respect to the beam, so that the wedge
can be carried normally with the beam, hanging.loosley between the latter and the
guide or bar, as the cage moves up or down. Upon the application of any force
tending to retard or stop the movement of the wedge, the descent of the cage will
bring the inclined face against the inclined side of the wedge, and the vertical face
of the wedge will be brought to bear against the vertical face of the bar until the
friction between the side of the. bar and the face of the wedge is such as to retard
or prevent the downward movement of the cage..
By varying the angle of the face of the wedge the relative degree of friction
between the faces inclined, and the vertical and the corresponding: faces of the
wedge may be changed, so that the friction on the inclined side of the wedge may
be equal to or greater or less than that between the wedge and. the bar thereby
deterinining the frictional resistance.
Different means may be employed for arresting or retarding the movement of
the wedge, for instance, it may be connected directly or indirectly with a governor
rope which rope travels with the cage passes between clamps and imparts motion
to a governor connected to said clamps, so that upon any undue speed, the said
clamps clutch the rope and hold it immovably, or with a determined frictional

page_text: resistance. It will be apparent that if the wedge or wedges are connected with
said rope, and the latter under the action of the governor, resulting from undue
speed of the cage, moves with a determined resistance, a constant pull will be
exerted on the wedge, while the beam of the platform or cage moving upon the
wedge will force the same against the face of the bar exerting a constant retarding
force and causing a speedy but uniform decrease of speed and the final arrest of tho
movement of the cage by holding it in frictional contact with the bars. Instead of
applying a frictional resistance to the movement of the rope the latter may be
clamped positively by the jaws, when the cage begins to move rapidly, and the
rope may be passed one or more times around a smooth drum turning upon a
journal secured to the frame of the cage, a chain or cable being connected to the
wedge and wound upon the drum. When the motion of the rope is arrested the
drum will be revolved and the, wedge will be drawn between the bar and beam
with a force limited by the friction between the surface of the drum and the rope
the latter sliding round the drum if the movement of the cage continues to any
great extent, the breaking of the rope being thus prevented As a general thing
two or more wedges are employed in which case a rope or chain extends from
each to the drum over suitable guide pulleys. To secure a greater amount of
frictional surface, and greater power than results from the use of a single wedge at
one or both sides of the cage. Additional wedges are employed and means whereby
to secure a differential action, or an action whereby a comparatively light power
arresting one wedge or series of wedges will secure a much greater force to arrest
the movement of other series.
For instance in connection with the devices already described slides may be
employed notched or recessed to fit the upright bars and loosley connected so as
to move with the cage, and supplemental wedges are placed between the inclined
faces of the notches in the slides and the bars. Where the upper portion of the
wedges constitute prolongations of the wedges, the slides are connected directly or
indirectly with the governor rope or supplemental rope and upon their movements
being retarded or stopped will cause the faces of the wedges to be jammed against
the bars, creating a definite frictional resistance to the movement of the wedge
greater than would result from any direct connection of the rope, with said wedge
and a still greater resistance to the movement' of the first wedge, is thus secured,
so that a comparatively slight tension upon the rope will ensure a powerful
frictional application of the wedges to the faces of the bars, and the arrest of the
downward movement of the cage. A slightly different arrangement is as follows.
The second wedge is separate from the first wedge and is. connected with a governor
rope, either by the intervention of the before mentioned drum or otherwise. The
first wedge being connected to a slide or clamp. The action in this case is the
same as in that previously described.
1
Instead of the rotating governor I may use a pneumatic or hydraulic governor
friction clutch or other device which will stop or retard the movement of the rope
if the cage moves too quickly. Instead of having the rope slip on the drum the
drum may be in two sections and the rope turn one section of the drum positively
and the other section may be held in frictional contact with the first and carry a
chain connected to a friction device. It will be apparent that the taper of the
wedges may be varied according to circumstances to secure a greater or less effect,
and that said wedges may be arranged between any part of the cage and the bars
or other stationary vertical object.

page_text: I, RUDOLPH C SMITH, Civil Engineer Yookers Westchester County N.Y do
hereby declare the nature of my said invention for SAFETY DEVICES FOR
ELEVATORS 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 Safety devices for Elevators, and
consists in the combination with the elevator cage and certain upright bars or.
guides, of devices for creating a determined and regulated frictional resistance, and
means for putting them in operation upon the too rapid descent of the cage, so as to
retard or arrest the downward movement.
-
One of the different modes of carrying out the principle of the invention is:
illustrated in the drawings, in which :-
Fig. 1, is an elevation of sufficient of an elevator to illustrate the invention,.
showing the cage, guides and safety devices.
Fig. 2, is an enlarged section on the line 1-2, Fig. 1.
Fig. 3, is a sectional plan of Fig. 1.
Figs. 4 & 5, are views illustrating modifications.
The cage or platform is of any suitable construction, and is combined with any:
of the usual elevating mechanism, whereby it is moved vertically within the well.
At opposite sides of the cage are the stationary parallel bars C, C, which may
constitute or supplement the usual vertical guide bars; and beneath the cage
extends a cross bar or beam A, having notches at the ends to receive the bars C.,
One side of each notch presents the face s, parallel to the face x, of the adjacent
bar C, the other side v, of said notch is inclined and at such a distance from face y,
of the guide, as to permit the introduction of a wedge B, the vertical face of which
is opposite the face y, while the angle of the opposite face m, corresponds to that of
the face v.
:
A lip or other suitable stop a, upon each wedge B, permits the limited downward.
movement of the latter with respect to the beam A, so that the wedge can be
carried normally with the beam, hanging loosely between the latter and the guide.
or bar, as the cage moves up or down,
Upon the application of any force tending to retard or stop the movement of the
wedge B, the descent of the cage will bring the inclined face v, against the inclined
side m, of the wedge, and the vertical face of the wedge will be brought to bear
against the face y, of the bar C, until the friction between the side y, of the bar₁
and the face t, of the wedge is such as to retard or prevent the downward movement
of the cage.
By varying the angle of the face m, of the wedge, the relative degree of friction
between the faces v & y, and the corresponding faces of the wedge may be changed,
so that the friction on the inclined side of the wedge may be equal to or greater or
less than that between the wedge and the bar C, thereby determining the frictional
resistance.
Different means may be employed for arresting or retarding the movement of
the wedge, for instance, it may be connected directly or indirectly with a governor.
rope F, which rope travels with the cage, passes between the clamps. e, e, and.
imparts motion to a governor connected to said clamps, so that upon any undue,

page_text: speed, the said clamps clutch the rope and hold it immovably, or with a determined
frictional resistance.
It will be apparent that if the wedge or wedges are connected with the said
rope F, and the latter under the action of the governor, resulting from undue speed
of the cage moves with a determined resistance, a constant pull will be exerted on
the wedge, while the beam A moving upon the wedge will force the same against
the face of the bar C, exerting a constant retarding force and causing a speedy but
uniform decrease of speed and the final arrest of the movement of the cage by
holding it in frictional contact with the bars. Instead of applying a frictional
resistance to the movement of the rope F, the latter may be clamped positively by
the jaws e, e, when the cage begins to move rapidly, and the rope may be passed
one or more times around a smouth drum E, turning. upon a journal secured to the
frame of the cage Fig 2, a chain or cable F1, being connected to the wedge and.
wound upon the drum.
When the motion of the rope F is arrested the drum E will be revolved and tho
wedge will be drawn between the bar and beam with a force limited by the friction
between the surface of the drum and the rope, the latter sliding round the drum if
the movement of the cage continues to any great extent, the breaking of the rope.
being thus prevented.
3
As a general thing two or more. wedges are employed, in which case a rope or
chain F', extends from each to the drum E, over suitable guide pulleys, as shown.
in Fig, 1...
-
To secure a greater amount of frictional surface, and greater power than results
from the use of a single wedge at one or both sides of the cage, I employ additional
wedges and means whereby to secure a differential action, or an action whereby a
comparatively light power arresting-one wedge or series of wedges, will secure a
much greater force to arrest the movement of other series.
For instance, in connection with the devices already described, I employ slides D
notched or recessed to fit the bars O, and loosely connected so as to move with the
cage, and supplemental wedges B¹, between the inclined faces of the notches in the
slides and the bars.
In Figs. 1 & 2, the wedges B¹, constitute prolongations of the wedges B, in which
case the slides D are connected directly or indirectly with the governor rope or
supplemental rope F1, and upon their. movements being retarded or stopped will
cause the faces of the wedges B¹ to be jammed against the bars C, creating a
definite frictional resistance to the movement of the wedge B₁, greater than would
result from any direct connection of the rope F, with said wedge, and a still greater
resistance to the movement of the wedge B, is thus secured, so that a comparatively
slight tension upon the rope F, will insure a powerful frictional application of the
wedges to the faces of the bars, and the arrest of the downward movement of the
cage.
'
A slightly different arrangement is shown in Fig. 4, where the wedge B¹, is
separate from the wedge B, and is connected with a governor rope, either by the
intervention of the before mentioned drum E; or otherwise, the wedge B, being
connected to the slide or clamp D. The action in this case is the same as in that
previously described.
Instead of the rotating governor illustrated, I may use a pneumatic or hydraulic
governor, friction clutch, or other device, which will stop or retard the movement
of the rope if the cage moves too quickly.
'
Instead of having the rope F, slip on the drum, the drum may be in two
sections 1, 2, Fig. 5, and the rope turn one section, 2, of the drum positively and
the other section, 1, may be held in frictional contact with the first, and carry the
chain F¹ connected to the friction device.
It will be apparent that the taper of the wedges may be varied according to
circumstances to secure a greater or less effect, and that said wedges, may be
arranged, between any part. of the cage and the bars or other stationary vertical
object.
'

page_text: Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The combination of a cage, sliding adjacent to vertical bars, wedges arranged
between the bars and parts of the cage, and a governing rope and connections with
said wedges and means for retarding the movement of the rope upon any undue
increase in the speed of the cage, substantially as set forth. .
2. The combination with wedges arranged to act between a cage and bars
contiguous thereto, one or more series of wedges connected directly or indirectly to
the first, and means for arresting the movement of the supplemental wedges when
the cage exceeds its normal speed, substantially as specified.
3. The combination of a cage, wedges arranged between the cage and vertical
stationary bearings, a governor rope and connections whereby upon any excess of
speed the wedges are drawn between the cage and bearings with a regulated power,
substantially as set forth.
>
4. The combination of the cage, wedges, governor rope and a frictional connection
between the governor rope and wedges, substantially as specified.
5. The combination of the cage, vertical bars, wedges B, supplemental wedges B¹,
and slides D, and means substantially as described for arresting the vertical move-
ment of the upper wedges when the cage exceeds its normal speed, substantially as
set forth.
6. The combination of the cage, bars and wedges, with the rope and friction
device, whereby the movement of the cage is permitted during a constant uniforin
pull upon the wedges, substantially as specified.
7. The combination of the governor rope, wedges, chains or cords F', and friction
device E, substantially as set forth.
PHILIP M. JUSTICE,
Applicant's Agent.