Improvements in Safety Appliances for Elevators or Lifts.
Year: 1889

page_text: Date of Application, 31st Dec., 1889-Accepted, 15th Mar., 1890
COMPLETE
SPECIFICATION.
Improvements in Safety Appliances for Elevators or Lifts.
I, WILLIAM PARKER GIBSON of 15 Queen Street in the City of London, 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 generally to improvements in elevators and particularly to
speed governing and automatic stop mechanism for the same.
The invention consists in a novel construction of speed governing apparatus
connected to the safety appliances of the elevator mechanism for arresting the descent of
the elevator car when it attains an undue speed, and of connections between said speed
governing apparatus and the rope which operates the valve of the elevator whereby
the governing apparatus in its operation of the safety appliances of the elevator also
acts through the rope to move the main valve of the elevator to arrest the descent of
the car.
The invention consists further in the combination with the speed governing apparatus
of a device operated in connection therewith to automatically arrest the elevator car
at its lower limit of movement.
The invention also consists of certain modifications in the arrangement of the
speeding governing apparatus, hereinafter referred to.
In the accompanying drawings-
Figure 1 is a front elevation of an elevator car and its connections, equipped with
speed governing apparatus embodying my invention.
Figure 2 is a horizontal section on the line 2 of Figure 1.
Figure 3 is a vertical sectional elevation on the line 3 of Figure 1.
Figure 4 is a vertical section on the line 4 of Figure 3 illustrating the construction
of the speed governing apparatus proper.
Figure 5 is a side view of the same.
Figure 6 is a section on the line 6 of Figure 5.
Figure 7 is a side elevation illustrating a modification in the arrangement of the
speed governing apparatus.
Figure 8 is a view similar to Figure 5 illustrating the combination with the same
of the automatic arresting apparatus.
Referring to said drawings it will be understood that A represents the elevator car,
B its hoisting cables, and the rope connected in the usual manner with the operating
connections of the main valve of the elevator mechanism for controlling the movements
of the power piston. The safety appliances of the elevator may be of any common
form, but as illustrated they are the same as described in my patent application of the
8th October 1889 No. 15,761 and need not therefore be particularly described herein,
reference being made to said application for a more detailed description of the same.
The hoisting cables B are connected to the safety appliances in one of the well known
ways and as described in my said application. The mechanism for operating the
rope C from the elevator car may be of any suitable form.
Referring now particularly to Figures 1, 4, 5 and 6 the speed governing apparatus
therein illustrated will be described. The speed governor proper, which will preferably
be located on the framework at the top of the elevator shaft, consists of a sheave d
grooved circumferentially for receiving a cable E passing around a pulley (not shown)
at the bottom of the shaft and connected with the safety appliances of the elevator and
travelling with the car. The sheaved is mounted loosely upon a shaft e held stationary
in vertical standards f by means of a key u (see Figure 4) or otherwise. The outer
face of the sheave d has pivotally secured to it, so as to be capable of a limited amount
of outward swing, a pair of levers 9 arranged parallel to each other upon opposite sides
g

page_text: of the shaft e. The levers gare retained in their normal positions by means of springs v
secured to the sheave d. The levers g carry arms i extending outwardly from the face of
the sheave d, which arms converge slightly towards each other at their outer ends
which are loosely connected to a collar seated in a recess formed in a sleeve k
arranged to turn freely upon the shaft e at the end of the sleeve 1. The sleeve has
connected to it one end of a spring m the other end of which is secured to a head n
fixed to the shaft e (see Figure 4). The sleeve l is splined to the shaft e as shown in
said Figure so as to be capable of movement along said shaft into engagement with
the sheave , the spring m holding said sleeve normally away from said sheave and in
the position shown in the drawings. For the purpose of ready engagement between
the sheave d and sleeve 1, their adjacent faces have formed upon them spiral
projections o. The projections o form a clutch, one member of which is carried by the
sleeve and the other by the sheave d.
The cable E is provided with stops 1, 2, the former engaging, with a projection 3
upon the car A and the latter with the end of an arm 4 connected to a rock-shaft 5
extending from side to side of the elevator car and carrying fingers 6 for engagement
with wedges 7 interposed between the guides 8 and the cross beam of the car A. The
arm 4 is held down in its normal position by means of a spring 9 located between the
end thereof and the projection upon the car A, the stops 1, 2, upon the cable E
causing said cable to travel with the car.
The operation of the apparatus thus far described is as follows. When the car is
travelling downward within its proper degree of speed the levers g upon the governing
apparatus will remain in their normal, parallel positions, the sheave d being caused to
revolve by the passage over it of the cable E connected to the car. When, however,
through any cause the speed of the elevator in its descent becomes unduly accelerated
its increase of speed will be communicated to the sheave d. As the sheave d thus
increases in speed the levers g will be thrown outward by centrifugal force from their
parallel positions, thereby causing the arms i to spread outward, and as the arms i are
thus spread apart they will draw the sleeve inward against the tension of its spring m
into engagement with the sheave d. When the sleeve and sheave d have been thus
brought into engagement, the former being fast to the shaft e, will prevent the further
rotation of the sheave. The sheave & being thus held stationary will act as a brako
upon the cable E and retard its movement sufficiently to raise the arm 4 and thereby
rock the shaft 5 and raise its fingers 6 upward to press the wedges 7 between the
guides 8 and the cross beam of the car. When the elevator has been arrested in its
descent the sleeve will be returned to its normal position by its spring m, and the
levers g and arms by the springs v.
The sleeve of the speed governing apparatus has connected to it the bifurcated
end of lever w, to the lower end of which is connected a cord D passing around a pulley r,
see Figure 2, the other end of which cord is jointed to the rope which passes around
a series of pulleys a b c q at the upper end of the elevator shaft. The cord passes
through a projections upon the framework of the elevator shaft and is held in its
normal position by means of a spring a bearing against said projection.
The operation of this mechanism is as follows. Whenever the speed of the car
becomes so accelerated as to cause the levers g to be swung outward and thus move
the sleeve inward toward the sheave d and before the sleeve has been brought into
engagement with the sheave d so as to operate the wedges in the manner described,
the lower end of the fulcrummed lever we will be rocked outward, drawing with it the
cord D. This movement of the cord D will draw the rope C upward and through said
rope operate the main valve of the elevator mechanism in the usual manner to retard
or arrest the movement of the car. If, however, the undue speed of the car should be
due to such causes that it is not checked by the closing of the valve the levers g will
continue to spread and will move the sleeve l into engagement with the sheave d with
the result before stated.
It will thus be seen that by means of the mechanism described provision is made
for the arrest of the car in its descent by the successive operation of its valve
mechanism and its safety appliances and the mechanism provided for the purpose is of

page_text: such construction that should there be any failure in the operation or effect of the
valve mechanism the safety appliances will still be effective.
Many changes may be made in the arrangement of the apparatus described
without departing from the spirit of my invention. Such a change is illustrated in
Figure 7. The speed governing apparatus in this case is mounted upon the car A,
with the cable E passing around its sheave d, the ends of said cable being secured at
the top and bottom of the elevator shaft. The shaft e in this case is journaled in a
bearing formed in a standard y and is extended beyond said bearing to receive the
end of a cord H the other end of which cord is secured to the arm 4 of the safety
mechanism as in the previous construction.
With this construction during the descent of the elevator car the sheave d moving
therewith will be rotated by its cable E, the sleeve / remaining out of engagement
with said sheave as in the previous construction until the descent of the elevator car
becomes accelerated beyond its proper limit. When, however, the car begins to
descend with undue speed the arins i will draw said sleeve and sheave into engage-
ment. In this instance, however, the shaft e not being keyed in its bearing y will at
the moment of such engagement have the movement of the sheave & transmitted to
it through its sleeve land will revolve therewith. As the shaft e revolves it will
draw upward upon the cord H and raise the arm 4 and through it rock the shaft 5
and fingers 6 and cause the latter to press the wedges 7 upward with the effect
heretofore described.
In the organization shown in Figure 8 the sheave d is mounted as in Figures 1
to 6 upon the framework at the top of the elevator shaft and has in this instance the
cable E of the safety appliances of the elevator passing over it. The shaft e is keyed
within a standard y and extends to within a short distance of the sheave d. The
sheave d instead of being mounted upon the shaft e is in this instance secured to a
shaft 10 journaled in bearings in standards 14 and threaded throughout a portion of
its length and provided with stationary nuts or abutments 11, one at each end of its
threaded portion, for engagement at the proper time with a travelling nut 12
mounted upon said shaft and having a projecting lower end entering a longitudinal
groove formed within a sleeve 13 enclosing said shaft by which the nut 12 is guided
in its movement along said shaft into engagement with the nuts 11 as the shaft is
revolved in reverse directions. The sleeve 13 is loose upon the shaft 10 so as to be
turned freely about the shaft and carries a pulley z around which the rope C for
operating the valve mechanism passes. The rope C is or may be in this case
connected to the cord D of the governor the same as shown in Figures 1 and 2, the
only difference being that the rope C passes around the pulley instead of around
the pulleys a, b, c, g..
The operation of the speed governing apparatus when thus organized is the same
as that of the organization illustrated in Figures to 6. In this case, however, the
revolution of the sheave d, which, as before remarked, is secured to the shaft 10,
causes said shaft to revolve in the same direction. During this revolution of the
shaft 10 the travelling nut 12 mounted thereon will travel along said shaft into
engagement with the nuts 11 and thereby lock the shaft 10 and its sheave d to the
sleeve 13 and thus cause the sleeve 13 and pulley z to partake of the movement of
the sheaved which will operate the rope C to stop the car. The movement of the
nut 12 along the shaft 10 will be so timed that its engagement with the respective
nuts will not take place until the elevator car has about reached its lower and upper
limits of movement. When the descent of the car becomes unduly accelerated the
arrest of the rotation of the sheave d will be accomplished in the manner described
in connection with the mechanism of Figures 1 to 6, the sleeve being advanced
along the shaft e into engage with the sheave d as heretofore described.
It is to be understood that changes may be made in the construction and arrange-
ment of the parts without departing from the invention. For example the apparatus
illustrated in Figure 7 may, by a slight change, be used equally well for operating
the rope C of the elevator to move the main valve to stop the movement of the power
piston, instead of operating the safety appliances of the elevator, or the apparatus

page_text: therein shown may be used for operating both the valve mechanism of the elevator
and at the same time its safety appliances. In the same way instead of the sleeve
sliding on the shaft the sheave may do so and for the arms g an ordinary ball or other
governor may be used.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The combination with the elevator car and its safety appliances, of a sheave
having one member of a clutch, a cable passing around said sheave to drive it at a
speed to conform to the movements of the car, a sleeve sliding upon a shaft, but
fixed against revolving upon said shaft and having the other member of the clutch,
levers pivoted upon said sheave to be swung outward by centrifugal force and
connected to said sleeve to move the same and operate the clutch to clutch the sheave
to the shaft when the movement of the car becomes excessive, substantially as
described.
2. The combination with the elevator car and its safety appliances, of a sheave (d)
driven at a speed conforming to the speed of the car, a speed governor driven by said
sheave a clutch operated by the speed governor to clutch the sheave when the speed
of the car becomes excessive and having one of its members connected to operate the
safety appliances when said sheave is clutched, a rope (C) connected to operate the
valve of the elevator, and connections between said rope, and the speed governor
whereby the governor will operate the valve to check the car, substantially as
described.
3. The combination with the elevator car and its safety appliances, of a cable (E)
connected to operate said safety appliances and passing over a sheave (d) so as to
drive said sheave at a speed conforming to the speed of the car, a speed governor
driven by said sheave, a clutch operated by the speed governor to clutch and arrest
said sheave when the speed of the car becomes excessive, a rope (C) connected to
operate the valve of the elevator, and a lever (w) connected to said rope and operated
by the governor, substantially as described.
4. The combination with the elevator car and its safety appliances, of a cable (E)
connected to operate said safety appliances and passing over a sheave (d) so as to
drive said sheave at a speed conforming to the speed of the car, a speed governor
driven by said sheave, a clutch operated by the speed governor to clutch and arrest
said sheave when the speed of the car becomes excessive, a threaded shaft (10)
driven by said sheave d, a rope (C) connected to operate the valve of the elevator
and passing over a loose pulley upon said threaded shaft and a nut 12 travelling
upon said shaft between fixed stops and connected to lock the pulley to the shaft as
the car approaches the limit of its movement in each direction, substantially as
described.
Dated the 31st day of Danambon 1900
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicant.