Improvements in and relating to Automatic Safety Gear or Appliances for Elevators.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Automatic Safety Gear or Appliances
for Elevators.
I, ROBERT JACKSON, of 98, Leslie Terrace, in the City of Aberdeen, Engineer
and Manager, do hereby declare the nature of my invention to be as follows:-
This invention has reference to improvements in and relating to automatic
safety gear or appliances for elevators, and has for its object to prevent the fall
of the elevator chains and buckets in the event of the chain or chains breaking.
According to my improvements hook or like shaped catches or pawls are
mounted to swivel or hinge on transverse bars located at any suitable point or points
on the elevator framing in the line of the forward and return chain of buckets.
Connecting rods from these catches are attached to opposite ends of a lever
fulcrumed on a fixed pin or bar, and a helical spring is mounted on one of
these connecting rods between the catch and a stop bar.
With this arrangement when the chain breaks, the following bucket comes in
contact with the catch on spring rod, and the weight of the chain and bucket
draws it out as far as the stop will allow. This action by means of the lever
and connecting rod will throw out the catch at the other side of elevator,
and so prevent the other part of the chain from falling.
There may also be attached a suitable connecting rod or rods which will
throw the elevator out of gear by means of a clutch or fast and loose pulleys or
equivalent arrangements used for driving.
Deted the 0th dow of Tul 1808
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.
Improvements in and relating to Automatic Safety Gear or Appliances
for Elevators.
I, ROBERT JACKSON, of 98, Leslie Terrace, in the City of Aberdeen, Engineer
and Manager, do hereby declare the nature of my invention and in what
manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement, that is to say:-
This invention has reference to improvements in and relating to automatic
safety gear or appliances for elevators, and has for its object to prevent the fall
of the elevator chains and buckets in the event of the chain or chains breaking.
And in order that my said invention and the manner of carrying same into
P 971

page_text: practice may be properly understood, I have hereunto appended two sheets of
explanatory drawings, in which Figures 1 and 2 represent views of two modified
arrangements of my improved automatic acting safety appliances for elevators.
Referring to Figure 1 of these drawings:-
According to my improvements hook or like shaped catches or pawls a a¹ are
mounted to swivel or hinge on transverse bars 6 located at any suitable point
or points on the elevator framing in the line of the forward and return chain
of buckets Z. Connecting rods c c from these catches a al are attached to
opposite ends of a lever fulcrumed on a fixed pin or bar d¹ and a helical
spring e is mounted on one of these connecting rods c between the catch a and a
stop bar f
With this arrangement when the chain Z breaks, the following bucket Z
comes in contact with the catch a on spring rod c, and the weight of the chain
and bucket draws it out as far as the stop f will allow. This action by means
of the lever d and connecting rod c¹ will throw out the catch a at the other
side of the elevator, and so prevent the other part of the chain from falling,
and a lever similar to h on Figure 2 may be fitted to throw out the clutch or
shift the belt on to the loose pulley, by means of the rod h¹.
In the arrangement shown on Figure 2, the catch a is hinged at a² and pro-
jects out past the line of the buckets Z, and as these ascend they press it back.
A small spring, not shown, is applied for keeping the catch a in the position
shown. A two armed lever d d is mounted on a spindle and the stop catch
prevents the arm & from rising too far. A lever is attached to the spindle d¹
but outside the elevator casing, and to this lever is secured the connecting rod h¹
for throwing the elevator out of gear.
The sliding catch or bolt a' is fitted to catch the down-going buckets Z, and
the guide a³ is for holding the bolt al in position.
In the event of the chain Z¹ breaking on the up going buckets Z, the weight
of the chain falls on the catch a and presses it down; and this action moves
the other catch or bolt a¹ and the lever h into positions to correspond, and catch
the down going chain, and throw out the ordinary clutch or shift the belt on
to the loose pulley.
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 -
An automatic safety gear or appliances for elevators constructed and arranged
to prevent the fall of the elevator chairs and buckets in the event of the chain
or chains breaking, substantially as herein set forth.
Dated the 27th March 1800
W. R. M. THOMSON & Co.,
96, Buchanan Street, Glasgow, Agents.