Electric and Compressed Air Motor.
Year: 1893

page_text: COMPLETE SPECIFICATION.
Combined Electric and Compressed Air Motor.
We, WILLIAM JOSEPH WALKER, and ALEXANDER LOUIS BEDFORD, of
4,232 Gratiot Street, St. Louis, State of Missouri, U.S.A., Gentlemen, 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:-
Our invention has relation to a combined electric and air motor, and consists in
the novel arrangement and combination of parts more fully set forth in the
Specification and pointed out in the claims. In the drawings, the figure represents
a side elevation of a car with paris broken away showing our invention applied
thereto.
In our present invention the immediate available energy by means of which the
motor is driven is compressed air contained within a suitable storage tank or
receptacle the walls of which are capable of resisting a suitable number of pounds
per square inch of surface. We have made provision for restoring the pressure
within said tank in the proportion that the air is utilized or consumed for the
operation of the motor, by means of an independent source of electrical energy
in the shape of a storage battery capable of operation both when the car is running
or at a stand still until the maximum or a definite pressure within said tank is
reached or maintained therein. The details of our invention may be described as
follows:
Referring to the drawings, I represents a car to which our invention is applied.
On top of the car, or in any convenient location is mounted a receptacle
or tank 2 of suitable size and capable of withstanding an internal pressure of
any suitable number of pounds per square inch of surface. From said tank
leads a pipe 3 conveying air by way of the two-way valve 4 and the pipe 5
(of which there are two one leading to each side of the car) to the valve chest 6
of the air cylinder 7, there being one such chest and cylinder and their
co-operating parts on either side of the car. The said cylinder and valve chest
are preferably located below the floor of the car, but we do not limit ourselves
to the precise location of the parts. The driving mechanism is of ordinary
construction and consists of the ordinary piston to which is connected the piston
rod 8. The cross-head 9 slides in a guide 10 and is secured to one end of the
main connecting rod 11 which in turn operates the wheel 12 on the rail 13, and
the connecting rod 14 connects the first wheel 12 to the wheel 15. The eccentric
rod 16 is connected to the rocker bar 17 secured in the present instance to a
depending casting 19, and the rocker bar operates the valve stem 20 secured to
the valve within the valve chest. All these parts are of the ordinary construction
and further details of description will be unnecessary.
In a suitable receptacle or box below the floor of the car is placed a secondary
or storage battery B from the opposite poles of which extend along the car
conducting wires 21, 22, the current from the battery passing through the same
and operating a dynamo D of any convenient type. The pinion 23 of the driving
shaft thereof meshes with a gear 24 to which is movably connected at a convenient
point, a connecting rod 25 which operates a rocking lever 26 which oscillates a
piston rod 27 of a cylinder 28 forming part of an air pump P of ordinary
construction. The piston rod 27 of the air pump operates within a slot 29 of the
rocking lever 26, the latter being pivoted at the point 30 to a suitable bracket 31,
as clearly shown in the figure. From the air pump leads a pipe 32 to a convenient
point in the tank 2, the said pipe conveying air to the tank either for purposes

page_text: of filling the said tank with compressed air when it is empty, or for the purpose
of keeping up the pressure within said tank as air is taken therefrom for
purposes of running the driving mechanism heretofore described. The tank 2 is
provided with a pressure gauge 33 connected to the tank by a pipe 31.
known manner.
At a convenient point in the path of the pipe 3 is a two-way valve 4 located
above the junction of the branch pipes 5, and from the casing of said valve and at
right angles to the pipe 3 is a pipe 35 of reduced diameter leading to any
convenient air brake mechanism (not showny which operates the brake 36 in a well
The two-way valve when turned in one position admits air through
the pipe 5 into the air cylinder 7; when turned ninety degrees from said position
it cut off air from the pipe 5 and admits it into pipe 35 thus operating the brake
mechanism. The object of having the pipe 35 reduced in diameter is for the
purpose of checking the flow of the air therethrough and thus apply the brakes
gradually.
When the limit of pressure within the tank 2 has been reached at any time,
particularly when the car has had occasion to be standing still and no air for
running purposes has been utilized, we provide means for stopping the operation of
the pump by shutting off automatically the current passing from the battery B
to the motor or dynamo D which operates the air pump P. "This is accomplished
by the automatic switch valve 37 Shown in sction in the drawing. The pipe 38
leads from the tank 2 and terminates in a plate 39 having a depending flange 40
which is interiorly screw threaded and to which is serewed a short tube 41 the
interior of which forms a chamber 42 above the valve 37. To the bottom of
the tube 41 is screwed a casing 43 into the open end of which is passed an
adjusting nut 44. Through this nut and through a central opening of a rib 45
within the casing and secured to the valve, passes loosely a valve stem it, and
between the adjusting nut 44 and the rib 45 is confined a spring 47 which encircles
the stem 46. By means of the adjusting nut the spring 47 is set to any desired
tension. It will be apparent that if too much pressure above the number of
pounds to which the spring is set accumulates in the tank 2, the pressure thereof
above the valve 37 will depress the same and consequently the stem attached to
the said valve. The lower end of the stem 46 is loosely connected to a switch
lever 48 pivoted in the path of the wire 22 on a switch board 49. It is apparent
that a depression of the stem 46 will throw the switch lever 4s or rather one end
thereof, off from the wire 22, thus shutting off the current from the dynamo, and
stopping the air pump which supplies air to the air tank 2.
From the above description the general character of our invention will be made
apparent. We have not limited ourselves to specific details of construction or
juxtaposition of parts; nor have we shown in the present drawings any particular or
specific air brake, the nature or construction of such air brake being unimportant,
since our present system may be applied to any of the ordinary air brake attach-
ments now in use. The location of the several parts as we have shown them is not
indispensable, provided however that the co-operative relation of the several parts is
preserved that is to say, a suitable source of electrical energy must always be used
as a means to replenish the gradually consumed air within the air tank, and that
such tank supply the necessary fluid to a suitable engine operating the driving
wheels. Nor do we limit ourselves to the particular application of our invention,
the same being capable with modifications, of running freight ears, passenger cars
as well as street cars, or in fact running any stationary engines.
Heretofore, so far as we are aware, compressed air alone has been used as a
motive power in running cars and the like, but it was accompanied by the incon-
venience of refilling the storage tanks at way stations and thus much time was
consuined; so also electricity has been used in the shape of storage batteries, but
as such batteries had to be genred directly to the running gear of said cars, the
efficiency of such systems was reduced to a minimum on account of the waste of
power. By our system these disadvantages have been overcome.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is:
1. A motor comprising a storage tank or receptacle for compressed air, a com-
pressed air motor operated by the same, an independent source of electrical energy
or a suitable storage battery, a motor or dynamo operated by the same, an air
pump driven by said dynamo, and pipes leading from said pump to the tank for
conveying air thereto and maintaining the necessary pressure within said tank,
substantially as set forth.
2. In a motor. a suitable storage battery: ŉ storage tank for compra air, a
suitable motor or dynamo and pump operated by the battery for forcing compressed
air to said storage tank, a switch lever pivoted in the path of the current from the
dynamo, a valve stem loosely connected to the switch lever, a suitable casing
having an adjusting nut and a rib with a central opening, the said stem passing
through said nut and the opening of the rib a coiled spring encircling said stem
and confined between the nut and rib, a valve connected to said stem, the said
valve communicating with a suitable chamber, and a pipe leading from the storage
tank to said chamber for conveying air thereto and operate the valve, the stem and
the switch, substantially as set forth.
3. In a motor, a suitable dynamo, means for operating the same, a pinion
mounted on the driving shaft of said dynamo, a gear driven by said pinion, a con-
necting rod loosely fixed to said gear a rocking lever operated by said connecting
rod, said lever being pivoted to a suitable bracket, a slot at the opposite end of
said lever, a suitable air pump, and a piston rod from said pump operating within
the slot of the rocking lever, substantially as set forth.
Dated this 20th day of March 1893.
ABEL & IMRA),
Agents for the Applicants.