IMPROVEMENTS IN SAFETY ATTACHMENTS FOR LIFTS AND HOISTS
Year: 1885

page_text: ,,
I JAMES ARCHER of Cocoa Works, York, Engineer do hereby declare the nature
of invention for "IMPROVEMENTS IN SAFETY ATTACHMENTS FOR LIFTS AND HOISTS
to be as follows:-
The object of this invention is to provide self acting doors or gates to close the
opening by which access is obtained to the cage when not closed by the cage itself.
Various means have been tried to accomplish this but for the most part they
are expensive and complicated and the mechanism is not confined to each separate
floor,
Little difficulty is experienced with the highest and lowest floors, but with the
intermediate floors great difficulty exists and I will describe my invention as
applied to an intermediate floor or stage.
The door or gate is arranged to slide in or upon grooves or guides in the side of
the shaft so as to close the opening in the absence of the cage. In or upon the
door or gate is arranged a latch pressed inwards towards the cage by a spring or
equivalent and capable of being withdrawn by a suitable lever whose arm comes in
contact with a stop when the gate has risen a certain height.
A cord chain or the like is fastened to the gate and passes over such pulleys as
may be necessary and carries on its other end another latch similar in action to
the first but adapted to rise and fall in grooves or equivalents in a direction
opposite to that of the cage. Upon the cage are suitable stops and the action is as
follows:-
When the top of the cage in rising comes in contact with the first latch it carries
it and thereby the gate up with it thus leaving the entry into the cage open and
at the same time the second latch is descending. The latch is carried up with the
gate until its arm comes in contact with the stop when it is gradually withdrawn
till it is clear of the cage and the gate is free to fall of its own weight.
Before however this can take place the second latch has sprung forward under
the bottom of the cage so that as the gate cannot fall without raising the second
latch and that can only rise as the cage rises, it follows that the gate can only
descend at the same regulated speed.

page_text: The latches may take into recesses in the cage if preferred but it is simplest to
use the top and bottom of the cage.
When the cage comes down again it first catches the second latch which is
drawn down with it thus raising the gate which reaches its maximum height as
the bottom of the cage reaches the floor level. The second latch is now withdrawn
in a manner similar to that of the first latch which having now sprung forward
above the top of the cage prevents the gate from falling so that it can only descend
again when the cage descends and at the same regulated speed.
I prefer to arrange intermediate positions for the latches when releasing so that
the final release may be more gradual.
Instead of the latches as described hanging catches may be used and I have
found them to work well.
The second latches are preferably made rather heavy so as to overcome friction
and keep the chains tight; all the stops may be made adjustable.

page_text: I JAMES ARCHER of Cocoa Works, York, Engineer, do hereby declare the nature
of my invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:
The object of this invention is to provide self acting doors or gates to close the
opening by which access is obtained to the cage when not closed by the cage itself.
Various means have been tried to accomplish this but for the most part they
are expensive and complicated and the mechanism is not confined to each separate
floor.
Little difficulty is experienced with the highest and lowest floors, but with the
intermediate floors great difficulty exists and I will describe my invention as
applied to an intermediate floor or stage.
The door or gate is arranged to slide in or upon grooves or guides in the side of
the shaft so as to close the opening in the absence of the cage. In or upon the
door or gate is arranged a latch pressed inwards towards the cage by a spring or
equivalent and capable of being withdrawn by a suitable lever whose arm comes
in contact with a stop when the gate has risen a certain height.
A cord chain or the like is fastened to the gate and passes over such pulleys as
may be necessary and carries on its other end another latch similar in action to
the first but adapted to rise and fall in grooves or equivalents in a direction
opposite to that of the cage. Upon the cage are suitable stops and the action is as
follows.
"
When the top of the cage in rising comes in contact with the first latch it carries
it and thereby the gate up with it thus leaving the entry into the cage open and
at the same time the second latch is descending. The latch is carried up with the
gate until its arm comes in contact with the stop when it is gradually withdrawn
till it is clear of the cage and the gate is free to fall of its own weight.
Before however,this can take place the second latch has sprung forward under
the bottom of the cage so that as the gate cannot fall without raising the second
latch and that can only rise as the cage rises, it follows that the gate can only
descend at the same regulated speed.
+
The latches may take into recesses in the cage if preferred, but it is simplest to
use the top and bottom of the cage.
irg
When the cage comes down again it first catches the second latch which is
drawn down with it thus raising the gate which reaches its maximum height as
the bottom of the cage reaches the floor level. The second latch is now withdrawn
in manner similar to that of the first latch which having now sprung forward
above the top of the cage prevents the gate from falling so that it can only descend
again when the cage descends and at the same regulated speed.
H
I prefer to arrange intermediate positions for the latches when releasing so that
the final release may be more gradual

page_text: Instead of the latches as described hanging catches may be used and I have
found them to work well.
The second latches are preferably made rather heavy so as to overcome friction
and keep the chains tight; all the stops may be made adjustable.
In the accompanying drawings Figure 1 is a vertical section through the "well"
showing the cage ascending: Figure 2 is a like view showing the cage descending.
Figure 3 is a cross section of the same. Figures 4 and 5 are details of the door
latch and Figures 6 and 7 are details of the balance weight and latch.
A is the "well" B.the cage and C the door sliding in vertical grooves and hung
by the chain or equivalent D which passes over the pulleys D' and D2 and carries
upon its other end the balance weight E.
In the bottom of the door C is the spring latch F shown in detail in Figures 4
and 5 the normal position of which is that shown in Figures 1, 4 and 5. As the
cage rises the projecting nose F¹ of this latch is caught by any suitable portion of
the cage as B¹ the door C which was resting at the floor line in Figure 1 being
thus raised by the top of the cage leaving a clear space from the floor into the
cage. In Figure 1 the door is lifted about half way up the chain D being kept
tight by the descent of the balance weight E.
By the time the floor of the cage B has come level with the floor of the building
and the door C has reached the limit of its upward travel the tail F8 of the latch
has struck any suitable fixed projection preferably an adjustable screw G, the
consequence of which is that the nose F¹ is withdrawn and the door is free of the
cage and rises no higher.
It would then fall of its own weight were it not for the nose H¹ of the latch H
of the balance weight E which being also a spring latch shoots out underneath the
cage in time to prevent the door from falling; the door C is therefore suspended so
long as the cage remains at that floor.
When the cage proceeds upon its upward journey the balance weight E and its
latch Hrise with it thus allowing the door C to fall until it reaches its lowest
limit or at about the floor line, so that by the time the cage is clear of the opening
the said opening is entirely closed by the door or gate C. It will be noticed that
the door can only rise or fall at the same rate at which the cago travels so that
severe shocks are avoided. When the. door is quite down the balance weight and
latch simply remain in the position they have reached and are not again interfered
with until the cage comes down again.
When the cage returns in its downward course the door is down and the balance
weight is up; the bottom of the cage therefore strikes the projecting nose H¹ of
the latch Hand carries the balance weight E down with it thereby raising the
door, until as the cage is in position at the floor the door C at the top of its travel
and the latch F engages with the top of the cage or the projection B¹. Figure 2
shows the cage descending the latch H engaged with the cage bottom and the
latch F free and ready to engage with B¹ at the proper time.
One face of each latch-nose E' and H is bevelled like the latch of a common
door so that as it comes in contact with its operating portion of the cage it is
readily pushed back. Thus B' as the cage comes down strikes the bevelled face of
F¹ and forces it back into its casing until B¹ has passed when it immediately
comes out again.
In Figure 7 latch H is shown upon an enlarged scale and turned the other way
round.
The plate I Figure 7 is fixed in the frame work in the proper position at about
the floor level and as the cage proceeds downwards it catches the tail H2 of latch H
and forcing it into the weight E withdraws the nose H leaving the weight clear
of the cage and free to ascend as the cage comes down the nose H sliding upon
The door C can of course
a metal plate provided upon the cage for that purpose.
be held by its latch on the top of the cage and can only descend with the cage.

page_text: The same action takes place at each intermediate floor whether the cage stops
there or not.
An antifriction roller H³ is preferably provided in the tail H².
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. In a hoist or lift apparatus the combination with the cage or moving platform
of a safety door or gate whose ascent (while the said cage or platform is rising) is
directly effected by the said cage or platform and whose descent is controlled by
the same in such manner that the rate of movement of said door or gate either up
or down is the same as that of the said cage or platform substantially as specified.
2. In a hoist or lift apparatus the combination with the cage or moving platform
of a safety door or gate whose ascent (while the said cage or platform is falling) is
effected by the said cage or platform and whose descent is controlled by the same
in such manner that the rate of movement of the said door or gate either up or
down in the same as that of the cage or platform substantially as specified.
3. In a safety attachment for hoists or lifts the combination with the safety
door or gate C of a balance weight such as E carrying a latch such as H the
whole constructed and operating substantially in the manner and for the purpose
specified.