Improvements in Automatic Brake Apparatus for Wheeled Vehicles.
Year: 1897

page_text: Date of Application, 7th Sept., 1897-Accepted, 23rd Oct., 1897
COMPLETE SPECIFICATION.
Improvements in Automatic Brake Apparatus for Wheeled Vehicles.
I, ED. SKAAR, of Kenyon, in the County of Goodhue, State of Minnesota, United
States of America, 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:-
My invention relates to brakes for wheeled vehicles and has for its object to
provide a brake, which will be automatically applied whenever, in going down-
hill, the vehicle is run forward by its own gravity, so that the draft rigging, or
harness of the draft animal, is caused to hold back the same.
To this end my invention consists of the novel devices and combination of
devices hereinafter described.
The preferred form of my invention is illustrated in the accompanying drawings.
Therein like letters refer to like parts, throughout the several views: -
Figure 1 is a view in longitudinal vertical section, taken through a wagon,
shown as equipped with my improved brake.
Figure 2 is a plan view of the wagon and brake shewn in Figure 1.
Figure 3 is a perspective view, shewing the brake device and a portion of the
wagon running gear to which the same is secured, the other portions of the wagon
being removed.
Figure 4 is a view, partly in side elevation, but principally in longitudinal
vertical section, of the end of the wagon pole and neck-yoke; and
Figure 5 is a section of a portion of the pole.
Referring to the parts of the wagon, a a¹ a indicate respectively, the wheels,
the axle and the pole of the front truck; and as a as indicate, respectively, the
wheels, the reach rod and the reach rod guide yoke, of the rear truck. As shewn,
the wagon tongue or pole a is pivoted on a rod aº, and the forward end of the
reach-rod a is pivoted to the front truck on a coupling pin a7. a8 indicates an
ordinary neck-yoke, provided with an ordinary pole-ring which works on the
end of the pole; and a indicates an ordinary two-horse equalizer to which the
whipple-trees (not shewn) are attached. This equalizer a¹ is, for the purpose of
applying my invention, secured to the pole a² and to the pole strap all, by means
of a pole-pin a¹ which works through a perforation in the said equalizer a10 and
through longitudinal slots a¹3 and a¹, respectively, in the said pole as and strap a¹¹.
These slots a¹ and a permit a limited to-and-fro movement of the equalizer on
the pole and the lower end of the pin a projects below the pole. The purpose of
this construction will appear later.
b indicates the brake-beam which extends transversely across the wagon, just
in front of the rear wheels, and it is supported on the forwardly projecting ends
of a pair of supporting arms 61, the rear ends of which are rigidly secured to the
rear axle. The brake-beam b is thus supported with freedom for a limited move-
ment, to and from the working faces of the rear wheels by means of bearing
irons secured to said beam 6 and guide bolts 63 passed through the said irons 62
and working in slot 6, in the ends of said supporting arms b'. At its ends, and
co-operating one with each of the rear wheel faces, the brake beam 6 is provided

page_text: with a pair of brake shoes, each of which, in the preferred construction shewn,
consists of a shoe block 65, a scraper spring 60 secured to the face of the said
block 65, and a wearing strip 67 secured to and forming a lining to the concave of
the scraper spring 66. It will be noted that the upper ends of the scraper spring 66
project above the parts 65 and 67, and are turned rearward so that they will engage
the running faces of the wheels a³, before the wearing strips b7 are thrown into
contact therewith, thus acting as scrapers and serving to clean the running faces
of the wheels before the brakes are applied.
To operate this brake-beam, a pair of cam levers c are pivotally mounted at
teir intermediate portions on a pivot bar c secured to the forward end of the
reach-rod guide-yoke a³. The upper ends of these levers c are provided with cam
surfaces which work in the grooves of bearing plates 68 secured on the front face
of the brake-beam. In order to hold the cam end of these levers c, in working
position against the bearing plates 68, and also to cause the said levers to withdraw
the brake shoes from working position, studs or rods c² are pivoted to the cam ends
of said levers c, as shewn at c³, with their other ends secured to the brake-beam b.
The lower ends of the cam levers c are connected for simultaneous and parallel
movement, by means of a triangular bracket d pivotally connected thereto at its
opposite corners. The rear end of a draw-rod di is passed through the apex and
base of the bracket d and is adjustably secured thereto by means of a set screw d².
The forward end of the rod d¹ is pivotally connected to the lower end of a lever f,
the intermediate portion of which is pivoted to the forwardly projecting lugs of a
fulcrum bracket f¹, which is rigidly secured to the forward central portion of the
front axle a¹.
A push-rod or thrust-bar g is mounted to work, with freedom for a limited
longitudinal movement, in a groove g¹ cut in the under side of the pole a². The
rod g is held upward within the groove g¹ by means of a long keeper plate which
is removably secured to the bottom face of the pole, and runs almost the entire
length of the same, but terminates a short distance from its free end. The rear
end of the rod g is pivotally connected at g³, to the forward end of a short link g',
the rear end of which is, in turn, pivotally connected to the upper end of the
lever f. The lower end of the pole pin as is passed through a suitable seat formed
in the rod g, at a point where it passes the said pin. This, of course, will cause the
rod g, pin a¹ and equalizer a10 to move together longitudinally of the pole. The
relations of these parts are such that when the equalizer 10 is drawn forward, so
that the pin a strikes the forward limits of the slots a¹ and a in the pole a³
and strap a", respectively, the brake shoes will, through the intermediate connec-
tions, be moved into their idle positions, or away from the running faces of the
rear wheels. Hence as long as the draft or drawing strain is applied to the
equalizer, the brakes will be held out of their working positions.
In order to render the brake mechanism inoperative so that the wagon may be
backed, I provide a lock which, as shewn and preferred, is as follows. indicates
a crank-like stop, which is mounted with freedom for both rotary and a limited
vertical movement in suitable seats formed in the pole strap all and the keeper
plate, at the bottom of the pole. The said crank is adapted to be turned in
line with and dropped into the slot a¹³ in the pole a. When thus turned, it will
prevent the pin a from being moved rearward far enough to set the brakes.
When the brake operating mechanism is set for automatic action, the stop
crank must be raised out of the pole slot a¹³, and is turned toward the rear so
as to engage with a groove k¹, cut in the pole, by which it is held in an inoperative
position.
Assuming that the draft animals are hitched to the wagon in the ordinary
manner, that is, to the neck yoke a8 and the equalizer a¹, by means of the ordinary
or suitable harness or draft rigging, the automatic action of the brake will be
substantially as follows:-As already stated, as long as the drawing strain is
applied to draw the wagon, the brakes will be held idle or released. When, how-
ever, as in going down hill, for instance, the wagon, under the action of gravity, is

page_text: caused to run forward, by itself, so that as the draft animals hold back on their
harness or draft rigging, the neck yoke as will be drawn rearward on the pole, and,
inasmuch as the drawing strain on the equalizer a10 is now released, this back pull
on the neck yoke as will cause it to bear against the lug on the said rod g, and will
force this together with the link g and other parts carried thereby, toward the
rear. As is obvious, by inspection of the drawings, this rearward movement of the
thrust or push rod g will, through the intermediate connections described, force
the brake beam b rearward and the working faces of the brake shoes into contact
with the running faces of the rear wheels. It is also obvious that the greater the
force or tendency the wagon may have to run forward or down hill, by gravity,
proportionately greater will be the force with which the brakes will be set. Hence,
it will be practically just as easy to prevent the wagon from running away in
running down a very steep hill as it will in running down a hill of very gradual
incline. As soon as the bottom of the hill is reached, and the drawing strain is
again applied to the equalizer a10, the brakes will be released and thrown out of
their working position, in a manner already described.
In my preferred arrangement of the brakes the relations of the bearing-plates 68
to the cam lever c and their pivots, are such that, when the brakes are set, they
will be self-locking, that is, will be set so that they will of themselves remain set.
This action is due to the fact that the point of contact between the cam ends of the
lever and the bearing-plate is, when the brakes are set, thrown so close to a
dead centre, that there will be but little tendency of the pressure on the brake-
shoes to throw the said levers c into their releasing positions.. The self-locking
action of the brakes is further assisted by the friction between the beam strips bi
and the bearing arms b³.
Attention is called to the fact that when the brakes stand in their released
position, the pivot joint g³, between the rod g and link g, stands directly under
and close to the pivot rod a of the pole a². Hence, when the free end of the pole
is dropped to the ground, this pivotal joint g³ will buckle, without causing any
perceptible movement of the brake operating connections. It will be noted, how-
ever, that this pivot joint g³ is such that it can buckle or turn in one direction only.
It will be understood, of course, that various alterations in the details of con-
struction above set forth may be made, without departing from the spirit of my
invention. For instance, so far as the broad idea of my invention is concerned,
the draft rigging or harness might take various forms and might be applied to the
brake connections in various different ways. Furthermore the term " draft rigging'
as used in this specification and in certain of the claims, is used in a very generic
sense, and is intended to include all draft appliances, whether the same be in the
form of a harness for a draft animal or animals, or connections to a mechanical or
artificial power device.
وو
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed I declare that what
I claim is:
1. The combination with a wheeled vehicle and draft rigging, of a brake beam
mounted to slide on suitable guides and provided with suitable brake shoes at its
ends, and automatic operating connections from the said draft rigging to said
brake beam, whereby a pair of cam levers, are operated so as to press the beam and
brake shoes against the wheels when the draft rigging is made to effect a back-
ward movement of the said operating connections relatively to the vehicle,
substantially as described.
2. In brake apparatus such as is referred to in the first claim, the combination
with the cam leverse that operate the brake beam, of bearing plates 6 fixed to
the brake beam and having vertical grooves in which the cam ends of the levers c
work substantially as described.
3. In combination with brake apparatus such as is referred to in the first claim,
a moveable stop device whereby the backward motion of the automatic operating

page_text: connections for applying the brakes can be prevented when it is required to back
the vehicle, substantially as described.
4. The combination with a wheeled vehicle, of a brake shoe or shoes operative
on the wheel or wheels of the same, and provided each with a projecting spring
scraper section arranged to engage the wheel, in advance of the application of the
brakes.
5. Automatic brake apparatus for vehicles combined and operating substantially
as herein described with reference to the drawings.
Dated this 7th day of September 1897.
ABEL & IMRAY,
Agents for the Applicant.