Electric Locking Devices for the Gear Wheels of Motors of Electric Cars (or Carriages).
Year: 1891

page_text: Date of Application, 13th Apr., 1991-Accepted, 25th July, 1891
COMPLETE SPECIFICATIVA.
Electric Locking Devices for the Gear Wheels of Motors of Electric
Cars (or Carriages).
I, GEORGE WEBBER BLANCHARD, of Waterville, in the County of Kennebec,
State of Maine, United States of North America, Electrician, do hereby declare
the nature of my invention for "IMPROVEMENTS IN CAR STOPPING DEVICES" and
in what manner the same is to be operated, to be particularly described and
ascertained in and by the following statement and accompanying drawing, that is
to say:
The chief objects of this invention are to provide a positive gear-locking device
for electric cars which will become operative to stop the car if the latter, on failure
of the current, begins to run backward down hill; and to arrange for controlling
the braking devices and also the impelling motor of the car by a single circuit
closer and indicator which may be located on the platform and easily manipulated.
To attain these objects I make use of the devices hereinafter particularly set forth
and claimed.
The accompanying drawing represents my improved gear-locking devices partly
in vertical section and side elevation and partly in diagram.
A represents the floor of the car. In a bushing fastened to the railing of the
car platform is journaled the horizontal shaft C of a hand-wheel C, said shaft also
bearing an indicator finger ("
The feed wire on entering the car passes first to a solenoid U and thence to a
switch-bar having a handle Y'. From this point the feed-wire divides, or,
speaking more exactly, there are two supplemental wires F, F. The former
extends directly from a contact on a switch-board (attached to the railing of
the car platform) to said shaft or an attachment thereof. The other wire 2
extends from another contact-post /2 on said switch-board to a small magnet
and thence to said shaft C, or an attachment thereof. When the switch-bar Y
is on contact the circuit is thus through solenoid U, and when said bar Y
is on contact the circuit is through the small magnet r, and through the
solenoid U also.
But
A magnetic bar Vis movable endwise up and down in the hollow core u of
solenoid U. It carries at its lower end a block V₁ provided with cog-teeth r
arranged to engage the motor-gears V, V, and thus lock the car whenever said
bar and block are left free to descend. While the solenoid U is in circuit the
said block is held up out of engagement and the gears V2, V3 are free to turn so
that the car may run. But a failure of electric current through said solenoid, from
any cause arising, will end the attractive power of said solenoid and the bar and
block will be no longer prevented thereby from falling and locking as stated.
this would be very inconvenient on level ground and in ordinary circumstances.
I therefore provide the said bar on one side with a shoulder or enlargement and
arrange a pivoted stop to bear obliquely upward against it, holding said bar from
falling. This stop is attached to a hanger or frame which is made fast to the
under-side of the floor of the car and also supports the said small magnet r. This
magnet is in proximity to said stop and arranged so that when energized it will
attract the upper part of said stop, which is metallic, away from said shoulder, the
stop turning as a pivoted armature against said magnet.
When this small
temporary magnet r is demagnetized the pivoted stop drops again into position for
holding up said bar and block. To allow this the magnet and stop are inclined as
shown.
The operation of this locking device is as follows: When running along level
around the circuit is through contact and solenoid U. the block is out of gear.

page_text: and the pivoted stop holds it so. If then the circuit is accidentally broken or the
current fails, the gearing will not be locked and the car will run for a short distance
by its own momentum, stopping gradually with no jar, or not stopping at all if the
defect be remedied in time, But in ascending a hill or just before doing so, the
switch-bar Y is shifted to contact as shown and the circuit is then through both
the solenoid U and the small inagnet 1. The former still holds the block out of
engagement with the gears, but the latter draws away the stop as described so that
there is nothing else to support said block. If then the current fails the bar and
block will drop at once before said pivoted stop can check them and the gearing
will be locked, preventing the car from running backward down hill.
As a modification of the construction and arrangement hereinbefore described,
the gears may be locked by electric magnets actuated by a secondary or local
circuit in the car, the current of said magnets being furnished by dry batteries
placed in the box with the magnets and the circuit-closer. The switch and con-
nections for the box are the same as in the arrangement described above, but
instead of the large magnet dropping a block into the gears, it closes a local battery
circuit which brings two dogs into the gear and allows them to move with it to the
pinching point, the supporting arms being centred on the axle.
The motor may be supported on bars extending across the car track instead of
being suspended from the car body. The braking and locking devices may be
operated from either end of the car. There is a block for locking the gears at each
side of the car since one block can lock only against motion in one direction.
Each block is controlled by an indicator at the respective end of the car.
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
1st. A locking device for the gears of an electric motor in combination with a
solenoid or magnet and electrical connections for holding said locking device out of
engagement as set forth.
2nd. In combination with the motor gears of an electrically operated vehicle,
a block provided with cog-teeth and arranged to automatically engage with said
gears, a solenoid or magnet which normally holds said block out of such engage-
ment and the necessary electrical connections and circuit-closing devices substantially
as set forth.
3rd. A. locking device for the motor gears of an electric car in combination with
a movable stop for holding it out of engagement, a magnet for withdrawing said
stop and the electrical conductors and circuit-closing devices, substantially as set
forth.
4th. A movable block provided with cog teeth and a metallic bar to which it is
attached in combination with the motor gears of an electric car, said gears being
arranged to be locked by said block when it descends, a solenoid and movable stop
independently holding up said bar and block, a magnet arranged to attract and
withdraw said stop, electric conductors making a circuit through said solenoid and
said magnet and a switch-bar controlling both of said circuits, substantially as set
forth.
1
EDWARDS & Co.,
35, Southampton Buildings, London, Agents for the Applicant.