Year: 1887

page_text: Date of Application, 22nd Sept., 1887
Complete Left, 10th Nov., 1887
Complete Accepted, 13th Dec., 1887
Michigan, U.S.A.
I WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for Foreign
Patent Solicitors 6 Lord Street Liverpool and 6 Bank Street Manchester both in
the county of Lancaster and 323 High Holborn in the county of Middlesex Civil
Engineer do hereby declare the nature of this invention to be as follows:-
In combination with a car or other vehicle two pair of gripping jaws or dogs of
peculiar forms bear against the faces of the rail or guide over which the vehicle
moves.
Each pair of jaws is preferably independently connected with the draft rope or
cable whereby each pair is adapted to independently engage with the supporting rail
in the event of breakage or sudden slacking of the draft rope or cable.
On the car as it traverses on the rails are two pairs of arbors, each pair being con-
nected by toothed gearing, and on each of said arbors an eccentric dog is carried.
Lovers project from these arbors and longitudinal rods connect said levers with the
draft rope or cable, in a peculiar manner, whereby the rods are permitted to move
backwards upon sudden slacking or breakage of the draft rope or cable and in moving
back to actuate the jaws and throw them into engagement with opposite faces of the
supporting or guiding rails.
The levers extend radially from one arbor of each pair, longitudinally moving rods
as already stated connect with these levers, springs bear against said rods, and tend
to force the same backward relatively to the direction of movement of the vehicle.
The draft rope or cable is independently connected with each of said rods and with
the car or vehicle.
By this means the rods are drawn and held forward against the pressure of their
(preferably encircling) springs when the draft rope or cable is under tension but are
permitted to move back when said tension is relieved.
1002
WILLIAM P. THOMPSON,
6, Lord Street, Liverpool.

page_text: 1, WILLIAM PHILLIPS THOMPSON F.C.S. M.I.M.E. of the Agency for Foreign
Patent Solicitors, G Lord Street, Liverpool, and 6 Bank Street, Manchester, both in
the County of Lancaster, and 323 High Holborn, in the County of Middlesex, Civil
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 to safety catches or locking devices for use upon cars,
elevator platforms, cages, etcetera, and it consists in a novel construction and arrange-
ment of eccentric gripping dogs to engage upon opposite sides of a supporting or
guiding rail and hold the car platform or other vehicle against sudden descent in
case of breakage of the draft or hoisting cable.
The invention is applicable to any and all conveyances moving vertically or at an
upward inclination, and liable in the event of breakage or disconnection of the draft
rope or cable to descend with dangerous rapidity.
In the annexed drawings: :-
Figure 1 represents the truck of a railway car provided with the improved safety
attachment.
Figure 2 an elevator car similarly provided, and
Figures 3 to 5 inclusive are details.
Various safety devices have heretofore been invented and applied to cars, elevators,
etcetera, and in some cases eccentric locking dogs have been arranged in pairs to
grip or bind upon opposite faces of a supporting or guiding rail in a manner
analogous to those of the attachment. As heretofore employed, however, such
devices have generally been so constructed or connected that each pair of jaws has
been dependent in action upon the other pair, so that if from any cause one pair of
jaws failed to act, the other pair has been provented from acting. This is a serious
defect in construction, for the reason that in the event of the rail being provided
with a fish plate, or other projection of any kind, which might interfere with or
preclude the action of the gripping jaws at a given point on one rail or guide, the
jaws at the opposite side, which are designed to engage with the other rail, are
prevented from acting, and thus the value and efficacy of the safety attachment is
destroyed.
By this invention each pair of jaws is caused to act independently of the other,
so that in case of obstruction on either rail or guide the jaws may freely grasp and

page_text: bind upon the other, and thus the device is caused to act with certainty under all
circumstances likely to arise.
Referring again to the drawings,
A indicates a car or vehicle, that in Figure 1 being designed for ordinary railway
tracks, and that in Figure 2 being a cage or platform for elevators; and B are the
rails or guides upon which or between which the vehicle moves; C, , and D, D, the
dogs or gripping jaws, arranged in pairs, one pair at each side of the vehicle, said
jaws or dogs consisting each of an eccentric or cam-shaped block having its outer
face serrated or provided with teeth to engage with the sides of the rails or guides B.
These teeth will be made preferably of the form shown in Figure 5, that is to say,
they will present in side elevation the form of saw or ratchet teeth, and will be rounded
from side to side, or in the direction of the axis of rotation, this rounding being
designed to enable the dogs to engage with the rails or guides, whether they be flat
faced or curved, and also to enable them to embed themselves more readily in the
metal of the rails or guides than they could do if presenting a straight face the full
width of the bearing face on the dogs.
Each dog or jaw C is carried by a shaft or arbor E, provided with sector gears
F and G, which intermesh and cause the dogs to move toward or from each other
simultaneously and equally when the arbors are rotated. The sector-gears G are each
formed with a lever or extension G', which extension is in turn connected with
rods H. The forward ends of the rods H are connected by chains I, I', or otherwise,
to a ring or clevis J, to which the draft rope, chain, or cable is attached. Another
chain K extends from said clevis or ring to and is connected with the frame or draw-
bar of the car, elevator, or other vehicle.
Each bar or rod H is pressed back by a spring L, in the form of a coil or helix,
encircling the rod and bearing at one end against a shoulder on the rod, and at the
other end against a fixed part of the frame of the vehicle. Said springs acting upon
the rods or bars, each independently, tend to force said rods backward relatively to
the direction of travel of the vehicle, and thus to rotate the arbors E, through the
action of the sector gears, in such manner as to throw the dogs inward toward each
other and to cause them to bind upon the sides of the rail or guide, which passes
between them as shown in Figures 1 and 2. When, however, power is applied to
the draft rope or cable, it draws said rods forward against the resistance of the
springs, which are thus compressed and held in a state of compression, such forward
movement of the rods rotating the arbors E in a direction opposite to that occasioned
by the compression of the springs, or in a direction to throw the dogs apart from
each other and out of contact with the rails or guides. This forward movement of
the rods and consequent separation of the dogs is limited by the chain K, which is
made long enough to permit the necessary forward movement of the rods, but which,
by the time such movement is completed, is drawn tant and receives the weight or
resistance of the vehicle and its load.
So long as the draft rope is under strain the rods will remain in their forward
position and the springs in a state of compression; but in the event of sudden
slackening or breaking of the draft rope or cable the draft rods will be thereby
released, and the spring acting upon them will force them instantly backward,
thereby acting upon the extensions of the sector-gears, rotating, the arbors E, and
throwing the dogs into engagement with the rails or guides. Owing to the
eccentricity of these dogs they will be forced inward with great pressure against
the rails or guides by the weight of the vehicle and its load, and caused to hug the
same so tightly as to preclude the downward or backward movement of the vehicle,
as will be readily seen, and in the event of either pair of jaws being prevented, by
fish plates or other projections upon the rail or guide, from properly swinging inward
and engaging effectually with the rail, the jaws at the other side of the vehicle being
wholly independent of and disconnected from the first pair, will still act promptly and
efficiently, it being the custom in laying such rails or applying the guides to alternate
the joints at opposite sides of the track or runway, and there being, consequently,
practically no danger of meeting with such obstructions at both sides simultaneously.

page_text: The precise arrangement or manner of mounting the toothed sectors, or of connecting
their levers, or extensions with the operating rods, is not deemed important, and in
fact it is necessary to vary the same somewhat in order to apply the devices both to
cars and to elevators and like conveyances.
As shown in Figure 1, where the invention is represented as applied to a car, the
levers or extensions G¹ are shown perforated or slotted for the passage through them
of the rods or bars H, which latter are provided with through pins a to bear against
opposite sides or faces of the extensions G, it being obvious, however, that any form
of shoulder or abutment may he adopted in lieu of the pins, to bear against the
extensions.
In Figure 2 an analogous arrangement is adopted, but for convenience of applica-
tion, and in order to avoid the presence of the rods at the middle of the car, which
would in many cases be inconvenient, each lever G₁ is connected by a rod H with a
second lever H¹, to which the chains are attached, the levers H extending across the
top of the car-frame from the side beams or standards to a point at or near the middle,
in line with the draft rope or cable.
It will be observed that under the construction and arrangement above described,
and shown in the drawings, either pair of dogs may act entirely independent of the
other, though under ordinary circumstances both pairs will act, and it will also be
seen that both in the case of cars and of hoists of all kinds, the two dogs of each pair
bear with equal force upon opposite sides of the rail or guide, so that the two forces
exactly equalize each other, and there is no spreading action exerted to force the rails
or guides from each other, as would be the case were the pressure applied to either
side alone. It will also be seen that by reason of the toothed gearing or connection
between the jaws of each pair their action is rendered positive, certain, and uniform.
It is obvious that good results may be secured especially in the case of elevators and
other vehicles having vertical or substantially vertical movement, without the aid of
the springs, the weight of the rods and the levers being in such case sufficient to
insure the prompt engagement of the dogs with the rails but it is preferred in all
cases to employ the spring because of the greater promptness and certainty of action
thereby secured.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. In combination with a car or other vehicle two independent pairs of gripping
jaws or dogs, the jaws of each pair being arranged, substantially as shown and
described, to bear against opposite faces of the rail or guide over which the vehicle
moves.
2. In combination with a car or other vehicle, two pairs of gripping jaws or dogs,
each pair independently connected with the draft rope or cable, whereby each pair is
adapted to independently engage with the supporting or guiding rail upon or over
which the vehicle moves in the event of breakage or sudden slackening of the draft
rope or cable.
3. In combination with a car or other vehicle, and with supporting or guiding rails
therefor, two pairs of arbors E toothed gearing connecting the arbors of each pair,
eccentric dogs carried one by each of said arbors, levers projecting from said arbors,
and longitudinally movable rods connecting said levers with the draft rope or cable,
all substantially as shown, whereby the rods are permitted to move backward upon
sudden slackening or breakage of the draft rope or cable, and in moving back to
actuate the jaws, and throw them into engagement with the opposite faces of the
supporting or guiding rails.
4. In combination with supporting or guiding rails B, a car or vehicle provided
with arbors E, gripping dogs C, secured to said arbors and arranged to bear against
opposite sides of said rails, toothed gearing connecting the arbors of each pair,
levers G¹, extending radially from one arbor of each pair, longitudinally movable rods
connected with said levers, springs bearing against said rods and tending to force the

page_text: same backward relatively to the direction of movement of the vehicle, and a draft rope
or cable independently connected with each of said rods, substantially as set forth.
5. The herein described safety attachment for cars, elevators, etcetera, consisting of
arbors E, dogs C, carried by said arbors, toothed gearing F, G, connecting said
arbors E, levers G, extending from the arbors E, and a draft rope or cable connected
independently with each of said levers.
6. In combination with guiding or supporting rails, a car or vehicle provided with
arbors E, dogs C, secured upon said arbors, gearing F, G, connecting the arbors of
each pair of levers G, extending from the arbors E, longitudinally movable rods H,
connected with said levers, springs L acting upon said rods, and a draft rope or cable
independently connected with each of said rods, and with the car or vehicle, sub-
stantially as shown and described, whereby the rods are drawn and held forward
against the pressure of the springs when the draft rope or cable is under tension, but
are released and permitted to move back when said tension is relieved, substantially as
set forth.
Dad...
Nhan 1007
WM. P. THOMPSON & Co.,
Agents for the Applicant.