ry
Year: 1887

page_text: Date of Application, 12th Apr., 1887
Specification Accepted, 13th May, 1887.
[Communicated from abroad by THE BAXTER ELECTRIC MANUFACTURING AND
MOTOR COMPANY, of Baltimore, Maryland, in the United States of America,
Manufacturers of Electrical Machinery.]
I, HERBERT JOHN ALLISON, of 52 Chancery Lane, London, in the County of
Middlesex, Patent Agent, 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 :-
The object of this invention is to furnish a governor which remains substantially
inoperative until the desired speed of the engine is attained, and which is susceptible
of prompt action through its entire range of motion within a comparatively small range
of variation above such normal speed. In my invention the centrifugal action of the
governor is resisted by a spring, but as the resistance of the spring naturally increases
with the expansion of the governor and its increased rate of speed, it is obvious that
the movement of the governor is resisted with an increased force as it attains a higher
speed of rotation; and such increased force would tend to prevent the free movement
of the governor within a limited range above its normal velocity.
To correct the increasing resistance of the spring and to oppose the governor by a
nearly uniform resistance, I combine with the spring a weight opposing a gradually
decreasing resistance, and make the action of the weight adjustable, so that its effect
upon the governor may be regulated at pleasure.
It is obvious that a uniform resistance will not balance the augmented power of the
governor at at increased rate of speed, therefore a very slight increase in speed.is
sufficient to render it most effective in actuating the regulating devices.
My improvements are shown herein applied to an electric motor in which a high
rate of speed is commonly required, and in which it is desirable to effect a prompt
regulation of the speed within a small limit above the normal velocity; but the governor
may be applied to any other use where it may be situated upon a horizontal shaft and
its centrifugal force opposed by a spring.

page_text: I have also shown herein an improved construction for the brush holders in an
electric motor, and means of making a movable connection between the same and the
field circuit to facilitate the use of my governor.
In the drawing Fig. 1 isa side view of an electric motor provided with my improved
governor, Fig. 2 is an elevation of the same at the end to which the governor is 5
applied, Fig. 3 is a vertical section on line a, a, in Fig. 2, the arbor and commutator
not being shown in section; Fig. 4 is a side view of the ring u¹ with the central
sleeve in section as well as the arm A to which the ring is attached, Fig. 5 is an end
view of the stationary governor pivot, Fig. 6 a side view, and Fig. 7 a view of the
inner end of the movable governor sleeve; Fig. 8 is a side view of the governor
swivel, Fig. 9 a side view of the swivel washer, Fig. 10 an end view of one of the
brush holders and its roller arm detached, and Fig. 11 a side view of the same.
A represents the frame of the motor sustaining the field magnets B and
bearings C, C, for the main arbor D. d is a shaft or an extension of the arbor
beyond the bearing C, and d¹ is a hub secured rigidly to the same, containing pivots e
for the inner ends of the governor links. f,f¹, are the governor links, the outer ends
of the latter being pivoted by pins g to a sleeve g¹ fitted to slide freely upon the
shaft d.
A swivel or collar h is secured upon the sleeve between a shoulder at its inner end
and nuts at its outer end; and a washer j is interposed between the nuts and the
swivel to diminish the friction caused by the thrust of the sleeve toward the swivel h
when in operation.
The centrifugal force, throwing the ends, f, of the governor arms outward, draws
the sleeve g¹ toward the bearing C; and the swivel collar h is provided with pins h¹
by which its movement is transmitted to a bell crank k, k¹, to shift the brushes 7 upon
the commutator m.
The brush carriers are pivoted at the opposite ends of arms 12 which are attached
to a spring box n containing a spring o, the inner end of which is secured to a stationary
brush pl projected from the bearing C.
In Fig. 4 the arms are shown turned with the brushes resting upon the commu-
tator as when the motor is first started, and a weight q is affixed to an arm projected
from the spring box in such position that its weight tends to unwind the spring in the
box when thus placed. The movement of the bell crank arm downward, as is effected
by an increased velocity of the governor, operates simultaneously against the weight,
which it is compelled to raise to a vertical position, and against the tension of the
spring which is at the same time coiled tighter by the rotation of the spring box n.
Mounting the weight to turn around a horizontal axis obviously decreases its
leverage as it moves toward a vertical plane through such axis; and a diminishing
resistance to the governor is thus produced by the weight, to counteract the increasing
tension of the spring, produced by the same rotation.
The resistance of the weight is obviously nothing, when moved over its own axis,
and as its initial resistance may be varied by its adjustment upon the arm r, its range
of effect may be correspondingly varied during its movement to the vertical
position, and the action of the governor be regulated in the most accurate manner.
The spring and weight are so adjusted to the normal velocity of the governor, that
the weight q is carried past the vertical line by any great excess above such velocity;
and the movement of the weight being downward thereafter, tends, with any further
acceleration in the speed of the governor, to oppose the tension of the spring
and to assist the governor in moving the regulating device attached thereto
with great ease and rapidity. The weight q is made adjustable upon the arm
so that its leverage may be varied at pleasure, and its effect upon the normal speed of
the governor and its resistance to the action of the same below the desired limit may
thus be changed as required.
The spring o is shown in Figs. 3 and 4 as a flat clock spring coiled within the
box n, and at one end secured to the box as by the screw n¹, and the other end
secured to a stationary point as the bush p'; but this construction of the spring is
immaterial as a wire spirally wound may be applied to the brush carrying arms in any

page_text: convenient manner provided the weight be connected therewith at one side of the
vertical line, and adapted to move to the other side of such line when the governor
has reached its normal limit of speed. To avoid resistance to the action of the
governor, I have devised a movable or rolling electrical connection between the brushes
and the field circuit; each brush carrier having an arm s pivoted at its outer end,
and provided with a roller s¹ bearing upon a metallic segment 2 which is sustained
concentric with the arbor D, and connected with the wires u from the field magnets B.
Each segment is represented as mounted in a wooden ring u¹ secured to the frame A
concentric with the commutator, and each segment as shown in Figs. 2 and 4, is held
in place by ears 3 which are secured against the inner flat side of the wooden ring u¹,
and serve partly to make the electric connection with the wires u. The brush carriers
are insulated upon the arms 2, and the current is conducted to the brush entirely
through the arms s and roller s which bears upon the segment s².
A coiled spring t is wound around the pivot of the arms s and has one ond attached
to the arm while the other bears upon the socket n² in which the brush is secured.
by a screw 13.
The reaction of the spring thus operates both to press the brush upon the commutator
and the roller s against the segment. The tension of the spring t is adjusted by the
manufacturer to produce the desired pressure of the brush upon the commutator, and
the rotation of the roller produces an electrical contact upon the segment s² without
producing any prejudicial resistance to the action of the governor.
The governor links are somewhat larger at their outer ends f2 which suffices to
produce the tangential inertia required at the high velocity employed.
When supplied with my governor, I have found that an electric motor may be
operated at 2000 to 5000 revolutions per minute with a full load, and the entire load
thrown off without affecting the speed of the armature, more than three per cent.
The governor links, which revolve rapidly with the shaft d, are surrounded by a
guard G, which consists in a circular casing attached to the frame A by a foot H.
Such guard is formed at its lower side with lugs I which carry the fulcrum 2 for the
bell crank k, k, and thus sustain the latter in a convenient relation to the swivel h,
which is overhung considerably beyond the bearing C
The arm k is bent to one side of the bearing C, as shown in Fig. 2, and its end thus
comes vertically beneath the pin v upon the arm 12 with which the bell crank is
connected by a link p. From the above description it will be seen that the essential
feature of my improvement in the governor is the combination therewith, of two
agencies as a spring and a weight exerting opposition to such centrifugal force; one
of such agencies exerting a gradually increasing resistance, and the other exerting a
gradually decreasing resistance.
The links ff, are, in my construction, the governor weights, and the centrifugal
force generated by their rotation is the effective agent by which the governor operates
to actuate the regulating device; and it is to that centrifugal force that the two
different agencies just referred to, are opposed. The essential feature of the improve
inent in the brush connections consists in the segments in electrical connection with
one of the field magnets, and a roller pressed elastically upon the segment and in
electrical connection with the brush.
Such a construction for the brush connections permits them to move with the utmost
ease while avoiding the use of a flexible wire cord such as is often used to connect the
movable brush holder with the magnet; and the freedom of movement thus secured
for the brush holder arms enables the governor to move the same with the utmost
facility and promptness.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed, I declare that what I claim is :-
1st. In a horizontal governor, the combination, with the rotating weights employed
for generating the centrifugal force, of two agencies, as a spring and a weight, exerting
opposition to such centrifugal force, one of such agencies exerting a gradually

page_text: increasing resistance, the other exerting a gradually decreasing resistance, and one of
such agencies adjustable to vary its resistance, and the whole being operated as and
for the purpose set forth.
2nd. In a horizontal governor, the combination, with the rotating shaft d, of the
fixed hub d¹, the movable sleeve g¹ and the links f, f', pivoted thereto and to one
another, a lever actuated by the sleeve, an arm rotated around the shaft d by the said
lever, and a spiral spring connected with said arm and with a fixed support, and
resisting the movement of the governor, as and for the purpose set forth.
3rd. In a horizontal governor, the combination, with the rotating links, of a movable
sleeve as gl, a lever as k, k¹, an arm rotated around a horizontal arbor by said lever, a
spiral spring connected with said arm and with a fixed support, and resisting the
movement of the governor, and a weight connected with said rotating arm, and
resisting the movement of the governor with a gradually decreasing force, as and for
the purpose set forth.
4th. In a horizontal governor, the combination, with the bearing C for the arbor D,
of the governor consisting in the links ff, rotated by an extension of the arbor
outside of the bearing C, and the guard G sustained upon the frame about the rotating
governor links, as and for the purpose set forth.
5th. In a horizontal governor, the combination, with the bearing C for the arbor D,
of the governor consisting in the links f, f¹, rotated by an extension of the arbor
outside of the bearing C, the arms for the brush carriers mounted upon a bush p inside
the bearing C, the bell crank k, k¹, pivoted upon the guard G and connected with the
brush carrying arms, all substantially as shown and described.
$2
6th. The combination, with a horizontal governor constructed substantially as
described, of the commutator of an electric motor, two segments s² supported con-
centrically about the commutator and connected respectively with the two field
magnets, the jointed arms s pivoted to each of the brush holders, the roller s¹ fitted in
the outer end of the arms, and the spring t operating to press the roller upon the
segment and the brush upon the commutator, all substantially as herein shown
and described.
ALLISON BROS.,
Agents for the Applicant.