An Improved Brake for Locomotives, Cars, and like Vehicles.
Year: 1891

page_text: Date of Application, 17th Nov., 1891-Accepted, 19th Dec., 1891
COMPLETE SPECIFICATION.
An Improved Brake for Locomotives, Cars, and like Vehicles.
T, CHARLES WARREN DUNCAN, of 417 Olive Street, in the City of St. Louis,
and State of Missouri, United States of America, Gentleman, 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 car and like brakes adapted to be automatically operated
by air or steam pressure or by vacuum, more particularly to locomotive driver
brakes, adapted to be operated independently of or in conjunction with the train
brakes. It has for its object the simplification and reduction of the number of
parts and such a construction as to readily permit of the getting at and replacing
when
of worn parts and in an efficient and convenient means for a "take up
worn; and consists in the novel features of construction and in consequent operation,
in a car brake, hereinafter described.
In the accompanying drawings, in which like letters of reference denote like parts
in the several figures,
Fig. 1 is a side elevation of my improved brake, as attached to a locomotive,
between two of the drivers ;
Fig. 2 is a view as in Fig. 1, showing the method of disconnecting as in replacing
a brake shoe; and
Fig. 3 is a cross-section taken on the line 3-3 in Fig. 1.
I have illustrated only my brake and that part of the operative mechanism
necessary to operate it. The brake, as a brake, can be, without modifying the
essential features of my invention, operated by compressed air or steam or by
vacuum. As illustrated, I operate my brake by compressed air admitted to the
underside of the brake cylinder piston and regulated by any of the well known
methods.
A represents the engine frame to which the brake cylinder B and the depending
brake hangers C C are attached. D and D' are, respectively, the forward and
rear drivers. E is the piston rod, to one end of which is secured the piston F.
To the other end of the piston rod E are pivotally secured one end of the arms G
and G', which are adapted to move about the pivot joint on the end of the piston
rod E in a plane parallel to the plane of the drivers D and D'. To the other ends
of the arms G and G¹ are pivotally and removably secured the ends, respectively,
of the adjustable connecting rod or spreader H, which is composed of two eye
bolts with right and left hand threads, respectively, let into the correspondingly
right and left threaded sleeve coupling I. The connecting rod H is designed to
retain the arms G and G¹ in such a position relatively that they form a wedge
shaped frame of the whole, resting, as shown in Fig. 1, in between the corre-
spondingly inclined surfaces of the brake hangers C and C. The contiguous
surfaces of the brake hangers C and C¹ and of the arms G and G' are formed,
respectively, with a tongue c and groove 9, as indicated in Figs. 2 and 3, to prevent
any lateral movement relatively.
The lower portion of the brake hangers C and C are formed with a laterally
projecting portion corresponding in form to the ordinary brake head to which the
brake shoes K and K₁ are removably secured by the bolts k. M M represent the
heads of the traverse bolts or steady rods connecting the brakes on either side of
the engine.
The principle of operation of my improved brake is.as follows:
Pressure is admitted to the cylinder B below the piston F which tends to raise
the piston rod Esand with it the attached arms G and G'. In this upward move-
ment of the arms G and G¹, which are held apart by the connecting rod H, the

page_text: inclined surfaces abut against the contiguous surfaces of the brake hangers C
and C forcing them apart against the drivers D and D', to the position as indicated
in dotted lines in Fig. 1. When the pressure is removed from beneath the piston F
the wedge-shaped frame composed of the arms G and G and the connecting rod H,
will drop to its normal position and the brake shoes K and K' secured to the brake
hangers C and C, will fall away from the drivers D and D.
1
When it is desirable to replace a brake shoe, as K (see Fig. 2), the removable
bolt which connects that end of the connecting rod to the brake hanger C (which
bolt is preferably secured by a spring key) is removed and then the hanger can be
dropped to a position away from the driver D, to the position as shown in Fig. 2,
convenient to remove the shoe K by removing the bolt k which secures it to the
hanger C.
Among the principal features of improvement in my new brake is in forming the
usual brake head in the same piece with the brake hanger. The advantages are
these-The two-the brake head and the brake hanger-being in one rigid piece,
and the brake shoe being rigidly secured to the same, the wear of the shoe will be
dependent only on the position of the pivot point at which the brake hanger is
pivotally secured to the engine frame about which it revolves as a center. This
point can be selected so as to give the most uniform wear to the shoe and so as to
wear the shoe most effectually, thereby doing away with the usual uneven wear
occasioned by the twisting movement given to the shoe by the turning of the
drivers when the brake is applied to the wheels.
The object of making the connecting rod H adjustable is in order to set the
arms G and G¹ the proper distance apart to secure the most effectual friction
between the brake shoes and the contact surfaces of the drivers when the pressure
is admitted to below the piston, when the brakes are applied, that is for the defined
amount of movement of piston head. This adjustment is also to be used when the
shoes are partially worn. The special form of construction of the operative part of
my brake, i.e., the part by which the brake is applied to the wheel, permits of the
adjustment above referred to being made with one adjustment, the turning of the
right and left threaded sleeve coupling I.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. In a locomotive car or like brake, a brake hanger in combination with a
removable brake shoe rigidly secured directly thereto, said brake hanger being
formed with a laterally projecting lug portion adapted to be fitted into a recess
formed in the rear side of the brake shoe, substantially as described and for the
purposes specified.
2. In a locomotive, car or like brake, brake hangers dependently secured in a
suitable position, said brake hangers being formed with inclined surfaces, arms
pivotally secured to the brake cylinder rod and a connecting rod retaining the said
arms at an angle relative to each other, combined and operating substantially as
described and for the purposes specified.
3. In a locomotive, car or like brake, the brake cylinder piston rod in com-
bination with arms pivotally secured to the projecting end of said piston rod; a
spreading rod removably connected with the free ends of said arms, retaining said
arms at an angle relative to each other; brake hangers dependently secured to the
supporting framework of the locomotive, car or the like said hangers being formed
with their adjacent surfaces inclined corresponding to the angle at which the said
arms are retained, combined as a whole and operating substantially as described and
for the purposes specified.
4. In a locomotive, car or like brake, the brake cylinder piston rod, in com-
bination with arms pivotally secured to the projecting end of said piston rod; an
adjustable spreading rod removably connected with the free ends of said arms,
retaining said arms at an angle to each other relatively; brake hangers dependently

page_text: secured to the supporting framework of the locomotive, car or the like said brake
hangers being formed with an incline on their adjacent faces corresponding with the
angle at which the arms are retained, the whole combined and operating substan-
tially as described and for the purposes specified.
5. In a locomotive car or like brake, the brake cylinder piston rod, in com-
bination with arms pivotally secured to the projecting end of said piston rod; an
adjustable spreading rod removably connected with the free ends of said arms,
retaining the said arms at an angle to each other relatively; hanger arms depen-
dently and pivotally connected to the supporting framework of the locomotive, car
or the like said hangers being formed with an incline on their adjacent faces
corresponding approximately to the angle at which the said arms are retained, the
contiguous faces of the said arms and the said hangers being formed with a tongue
and groove, respectively, and brake shoes removably secured to said hangers,
substantially as described and for the purposes specified.
Dated the 17th day of November 1891.
PHILIP M. JUSTICE,
Associate Agent.