A Safety Device for Corliss Engines.
Year: 1899

page_text: Date of Application, 27th Oct., 1899-Accepted, 23rd Dec., 1899
A Safety Device for Corliss Engines.
We, WILLIAM FRANKLIN BRADBURY, of 2048, North 13th Street, in Kansas
City, in the County of Wyandotte, in the State of Kansas, one of the United States
of America, Mechanical Engineer, and DIXON EVERETT WASHINGTON, of 2310,
Summitt Street, in Kansas City, in the County of Jackson, in the State of Mis-
souri, one of the United States of America, Engineer, do hereby declare the nature
of this invention and in what manner the same is to performed to be particularly
described and ascertained in and by the following statement:-
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Our invention relates to a new and useful safety device for Corliss engines, for
controlling and stopping the engine when a determined speed above the normal
working speed is reached. We are aware that a number of devices have been placed
before the public notice for controlling and stopping an engine and preventing
running away." But heretofore all such devices have been connected with the
governor or controlled and put into operation by the governor or governor
mechanism, and may or may not act within the safety limit of speed. The object
of our invention is to provide a safety device connected directly with and put in
operation and controlled by the action of the valve mechanism, so that so long as
the valve mechanism is in operation the device will be in opera-
tive relation therewith and controlled thereby, regardless of other parts
and mechanism, it being apparent that when the valve mechanism stops no
safety device is needed; and a device capable of such adjustment that when a
determined speed above normal is reached the engine will be at once stopped; and
to attain this object our invention consists of certain features of novelty herein-
after described and pointed out in the claims.
Figure 1 represents an end elevation of the valve mechanism of a Corliss engine,
provided with our safety device.
Fig. II represents an end elevation of the same viewed from the opposite side.
Fig. III represents a side elevation of the same.
Fig. IV represents a detail elevation of our safety device.
Fig. V represents a view partly in cross section of the line X X of Fig. II.
Fig. VI represents a view showing relation of auxiliary weight.
Similar numerals refer to similar parts throughout the several views.
1 represents the valve stem. 2 represents the valve stem crank on which are
mounted the catch block 3 and the dash pot rod 4 (Fig. 1). 5 represents the
governor crank. 6 represents the wrist plate crank connected by the rod 7 with
the wrist plate (not shown). 8 represents the crab claw crank carrying the latch 9
and the trip arm 10.
In relation to these parts common to all Corliss engines our device consists of a
block 11 mounted by means of the plate 12 upon the sleeve of the bell crank, so
that the block is given an oscillating movement corresponding to the oscillations
of the crank. In said block 11 is journaled a shaft 13, the outer end of which
passes through an opening 14 in the crab claw crank. Beyond said crank a por-
tion, substantially half, the shaft is removed providing a flat face 15 on the

page_text: diameter of the shaft arranged closely adjacent to the face of the trip arm 10
when the latch is in engagement with the catch block 3. On said shaft 13 is
fixedly mounted an arm 16, on which arm is adjustably mounted a weight 17, in
such relation that when the weight is in its elevated position as shown in heavy
lines in Fig. II the flat face 15 of the shaft is in line with the face of the trip
arm 10 as above stated. To retain the shaft in the position designated against
the action of the weight, in a recess in the block 11 a disk 18 is fixedly mounted
on the shaft, provided with the V shaped indentation 19 and the square shouldered
indentation 20, and in another and longitudinal recess 21 in the block is provided
a catch 22 having a V shaped extremity 23 arranged to take in the V shaped
indentation 19 in the disk. To retain said catch in engagement with the disk,
on said catch is provided a stud 24 extending into an adjacent recess 25 in which
is located a coiled spring 26 arranged to bear on said stud, the tension of said
spring being controlled and regulated by the screw plug 27 bearing thereon. A
plate 28 is provided to close the recess 21. 29 represents a lever fulcrumed
at 30 in the side of the block adjacent to the catch recess; one arm of said lever
terminating in a V shaped nib 31 engaging a V shaped notch 32 in the side of
the catch, and the other arm having adjustably mounted thereon the weight 33,
the function of which will appear.
In operation, by the action of the wrist plate in operating the valve mechanism,
an oscillating movement is given to the crank arms 6 and 8 and a coincident and
corresponding oscillating motion is given to the block 11 and the weight 17
mounted on the shaft 13 journaled in said block, the weight being held in position
by engagement of the catch 22 in the V shaped notch in the disk 18, as above
stated. By this oscillating motion due to the oscillating motion of the cranks, a
certain momentum is generated in or given to the weight and the degree of this
momentum as is apparent, is dependent upon the rapidity of oscillation of the
cranks, such oscillating of course corresponding to the speed of the engine. The
tendency of this momentum generated in the weight is to cause the shaft 13 to
turn and to disengage the catch from the notch in the disk. To resist this impulse
due to the momentum of the weight and retain the weight in position at normal
speed, the tension of the spring 26 is set by the screw plug 27 to such degree that
the catch is held in the notch with sufficient force to prevent escape and hold the
weight up at normal speed. But when the speed increases above normal to a
desired and determined point within the limit of safety. the momentum of the
weight will overcome the restraining force of the spring, the disk will escape from
the catch. and the weight will be thrown down until the catch engages the
shouldered notch 20 as shown in dotted lines in Fig. II and IV. By this action
of the weight the shaft is turned quarter round and in so turning the quadrant
adjacent to the trip arm of the latch acts as a trip to engage the latch trip arm
throwing the latch out of engagement with the catch block and preventing further
engagement therewith, and thereby instantly and completely cutting off further
admission of steam to the engine. The tension of the spring in relation to the
momentum of the weight may be adjusted to a very great micety, it being found
in practise that such adjustment can be made so that in an engine running nor-
mally at ninety revolutions, two revolutions above normal will cast the weight
and shut off the steam. To assist in raising the catch 22 to release the weight 17,
we provide the weight 33. on the lever 29. This weight having a momentum
similar to that of weight 17 and acting to raise the catch. The lever is also useful
to raise the catch from the shoulder notch 20 to restore the weight 17, to position.
We preferably use the weight as above described impelled by the momentum
derived from the oscillation of the valve gear to, operate the trip and release the
latch. It is however apparent that other means may be used, independent of the
governor and governor mechanism to operate such trip without departing from the
principle of our invention, the principle of our invention being the application
of a power or force to release and control the latch actuated and controlled by
means independent of the governor and governor mechanism.

page_text: of our
Having now particularly described and ascertained the nature
invention and in what manner the same is to be performed, we declare that what
we claim is
1. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism of a weighted trip mounted on the bell crank sleeve
and arranged to be operated by the momentum imparted by the oscillations of
the bell crank to trip the crab claw at a certain pre-determined speed limit, and
means connected with and arranged to control said trip until such speed limit
is reached, substantially as set forth.
2. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism of a weighted trip mounted on the bell crank sleeve
and arranged to be operated by the momentum imparted by the oscillations of
the bell crank to trip the crab claw at a certain pre-determined speed limit, and
a catch connected with and arranged to control said trip until such speed limit is
reached, substantially as set forth.
3. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism of a weighted trip mounted on the bell crank sleeve
and arranged to be operated by the momentum imparted by the oscillations of the
hell crank to trip the crab claw at a certain pre-determined speed limit, and a
spring controlled catch connected with and arranged to control the trip until
such speed limit is reached, substantially as set forth.
4. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism of a trip mounted upon the bell crank sleeve arranged
to act upon the crab claw, a weight connected with and arranged by its oscillating
momentum at a certain pre-determined speed limit to operate said trip, and
means connected with and arranged to control said weight until such speed limit
is reached, substantially as set forth.
5. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism of a trip mounted upon the bell crank sleeve arranged
to act upon the crab claw, a weight connected with and arranged by its oscillating
momentum at a certain pre-determined speed limit to operate said trip, and
a catch connected with an arranged to control said weight until such speed limit
is reached. substantially as set forth.
6. A safety device for Corliss engines, consisting of a trip mounted upon the
bell crank sleeve arranged to act upon the crab claw, a weight connected with and
arranged by its oscillating momentum at a certain pre-determined speed limit
to operate said trip, and a spring controlled catch connected with and arranged to
control the weight until such speed limit is reached, substantially as set forth
7. A safety device for Corliss engines consisting of a block mounted on the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight mounted on said shaft arranged to operate the trip, and a spring catch
arranged to control the weight when the parts are so arranged that the oscillating
momentum of the weight controls the trip: substantially as set forth.
8. A safety device for Corliss engines consisting of a block mounted on the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight mounted on said shaft arranged to operate the trip, and a spring catch
arranged to control the weight, when the parts are so arranged that at a certain
speed the oscillating momentum of the weight will overcome the resistance of the
catch and operate the trip: substantially as set forth.
9. A safety device for Corliss engines consisting of the combination with the
valve operating mechanism, of a block mounted on the bell crank sleeve, a shaft
journaled in said block arranged to trip the crab claw, a weight mounted on said
shaft arranged to operate the trip, and a spring catch arranged to control the
weight, when the parts are so arranged that the oscillations of the bell crank
beyond a certain speed limit will cause the release of the weight and the opera-
tion of the trip; substantially as set forth.

page_text: 10. A safety device for Corliss engines consisting of a block mounted on the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight mounted on an arm fixed on said shaft, a disk having suitable notches in
its periphery mounted on said shaft, and a spring catch arranged to take in said
notches; substantially as and for the purposes set forth.
11. In a safety device for Corliss engines a block mounted upon the bell crank
sleeve, a shaft journaled in said block having at one end a flattened face arranged
to, trip the crab claw, and means for controlling and operating said shaft; sub-
stantially as set forth.
12. A safety device for Corliss engines consisting of a block mounted on the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight mounted on an arm fixed on said shaft, a disk having suitable notches in
it's periphery mounted on said shaft, a spring catch arranged to take in said
notches, and a weighted lever fulcrumed in said block arranged to act on said
catch against the tension of its spring; substantially as set forth.
13. A safety device for Corliss engines consisting of a block mounted on the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight adjustably mounted on an arm fixed on said shaft, a disk having suitable
notches in its periphery mounted on said shaft, and a spring catch arranged to
take in said notches; substantially as and for the purpose set forth.
14. In a safety device for Corliss engines a spring catch consisting of a block
having suitable adjacent recesses, a catch arranged on one of said recesses, a
stud on said catch extending into the other recess, a spring in said recess arranged
to bear on said stud, and a screw plug arranged to control the tension of said
spring substantially as set forth.
15. In a safety device for Corliss engines, a block mounted upon the
bell crank sleeve, a shaft journaled in said block arranged to trip the crab claw,
a weight mounted on said shaft arranged to operate the same to trip the crab claw
at a certain pre-determined speed limit, and a catch connected with and arranged
to control said weight until such speed limit is reached, substantially as set forth.
Dated this 27th day of October 1899
WILLIAM FRANKLIN BRADBURY,
DIXON EVERETT WASHINGTON.
Herbert Haddan & Co.,
Agents to Applicants, 18, Buckingham Street, Strand, W.C.