Improvements in and connected with Electric Motors.
Year: 1899

page_text: Date of Application, 4th July, 1899-Accepted, 19th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in and connected with Electric Motors.
A communication from abroad by THE EMERSON ELECTRIC MANUFACTURING
COMPANY, a Corporation organized under the laws of the State of Missouri,
United States of America, of the City of St. Louis, in said State.
I, PHILIP MIDDLETON JUSTICE, of 55 and 56, Chancery Lane, in the County of
Middlesex, Fellow of the Chartered Institute of Patent Agents, 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:-
This invention relates to a new and useful improvement in and connected with
electric motors, the object being to provide means whereby said motor may be
direct acting with relation to the shaft to be driven.
Motors have already been extensively employed in different ways, to drive
machinery, in which a counter shaft has been employed, or a clutch interposed
between the armature shaft and the shaft to be driven, or the armature shaft has
been made the main driving shaft of the machinery. The prime object in view
with this present invention is to simplify the method of driving a shaft of a
piece of machinery, and further, to provide means whereby the armature shaft
may be coupled to the driving shaft, so that said driven shaft will immediately
start off at full speed, and when the armature shaft is disengaged from the driven
shaft, the driven shaft is braked so as to cause it to stop immediately. These
conditions apply particularly with relation to a sewing machine, which is the
machinery driven by the motor illustrated in the drawings, but it is, of course,
understood that other conditions may arise which may require a modification of
the details of construction to meet the new conditions. It will be further under-
stood, that, while there is illustrated a sewing machine in the drawing as the.
machinery driven by the motor, yet, it should be distinctly understood, as not
confining the application of the invention to this particular machine, that there
are many other machines to which the invention can be applied with equal facility,
such as pumps or bellows for organs, small lathes, and the like.
The essential feature of this present invention reside in the arrangement of
a friction-disk or clutch on the shaft to be driven, with which co-operates a
friction-disk or clutch driven by the armature shaft; another feature resides in
the novel means employed for laterally displacing the armature, its shaft and
associate parts, whereby the friction-disk carried by the armature shaft is thrown
into engagement with its companion on the shaft to be driven; another feature
resides in the novel means of disengaging the friction-diska from each other,
which consists in moving the armature, its shaft and associate parts laterally,
when the armature shaft is released, by the magnetism of the field magnets;
another feature of the invention resides in the novel means employed for moving
the armature and its associate parts laterally, so that the friction-disk carried
thereby will engage its companion, said means simultaneously releasing the

page_text: companion disk on the shaft to be driven; and, finally, the invention consists in
the construction, arrangement and combination of the several parts, all as will
hereinafter be described, and afterwards pointed out in the claims.
In the accompanying drawings forming part of this specification, wherein like
symbols of reference refer to like parts in the several figures:
Figure 1 is a sectional view through a motor, showing the relation of our attachi-
ments thereto.
Figure 2 is a view in side elevation, showing the manner of arranging a motor
to operate a sewing machine.
Figure 3 is a top plan view of the same, the sewing machine being thrown back,
so as to permit the armature of the motor to be withdrawn.
Figure 4 is a partial sectional view, illustrating a slightly modified form of the
improved attachment.
Figure 5 is a similar view showing another modified form of the attachment,
and
Figure 6 is a detail view in top plan, showing the manner in which the brake-
shoe is secured to the lever.
I
A represents a sewing machine head mounted upon its base a, said base being
preferably hinged on its rear edge to a table or stand B, as is usual.
C represents the main shaft of the sewing machine, or the shaft to be driven,
on which is fixed a friction-disk D, its side face being preferably grooved for
reciving a leather or fibrous ring d, which projects laterally beyond the side face
of the disk. If desired, it will, of course, be understood that disk C need not
be mounted directly upon the main shaft of the sewing machine, but said disk
can be mounted on a counter shaft, and have conjoined thereto a pulley, around
which would run the usual round belt, and in that manner the driven shaft can
be belted to the sewing machine, which would not necessitate the removing of
the hand wheel from said machine, as will be well understood.
E represents an electric motor, preferably arranged in axial alignment with the
shaft to be driven, which position is illustrated in the drawings, as being directly
back of the sewing machine head. This motor may be of any usual and well
known construction, and may be run either by alternating or direct currents, as
best adapted to requirements. The motor shown in the drawing, is adapted to
be run by au alternating current, and consists of suitable casing E, which supports
the laminated field magnet cores F, the windings of said field magnets not being
shown. A removable face. plate E", may also be provided to give a finished
appearance to the casing, and by preference, this face plate is formed with a
central aperture or opening e, of such diameter as to pormit the insertion and
withdrawal of the armature therethrough.
As shown in Figure 1, casing E has a fixed hollow shaft G, mounted therein,
for containing a suitable lubricant, the ends of said hollow shaft receiving
suitable plugs g, in which is slidingly mounted a rod, which will hereinafter be
described.
H indicates a sleeve carrying bushings h, which are bored for the fixed shaft,
and which form bearings for said sleeve. The inner end of sleeve H is preferably
formed with an annular knife edge, which normally bears against a washer h
to prevent the escape of the lubricant into the motor. An absorbent ring hil
surrounds the washer h", for the purpose of catching and absorbing any lubricant
which might escape.
I is the laminated core of the armature, which is mounted on sleeve H. The
type of motor shown being. what is. commonly known as an induction motor, does
not need any but closed windings in the armature, and, therefore, no. commutator
or brushes are shown.
The copper bars which are arranged in. the periphery, of the armature are
indicated by dotted lines, and are short. circuited by a copper ring at each side
of, the armature, all of which is well understood.
J indicates the friction-disk, which is mounted on the outer end of sleeve H,

page_text: in such a position that, when the armature and its associate parts are moved
laterally, said friction-disk will contact with its companion, and drive the latter.
K indicates a rod or bar which is slidingly mounted in the plugs g, one end
of which bears against the hub portion of the disk J, while its rear end projects
outwardly, and is engaged by the upper end of a lever L, which is preferably
pivoted at 7, to the motor standard. In order to make the end thrust against the
rod K yielding, there is preferably mounted a spring pressed thimble M,
in the upper end of lever L, which thimble bears against rod K,
and when levor L is moved so as to force the disk. J into engagement
with its companion, thimble L will yield sufficiently to permit a slight further
movement of the lever L. This is desirable, as the yielding thimble M may be
adjusted by the set sorow m, and thus compensate for any inequalities in the
manufacture of the motor or its parts. Lever L is normally held in its outer
position through the instrumentality of a compression spring N, whose tension
may be regulated by the set screw n. It is, of course, understood that a weight
would accomplish the same purpose.
The inner end of lever L, carries the brake-shoe O, which may be of leather or
other suitable material, and which, as shown in Figure 6, is bent over the inner
end of said lever, and clamped in position by two clamping plates o, which are
held in place by a screw o
In the event that it is desired to control the rotation of the driven shaft by
the foot, there is attached a rod, to the inner end of lever L, and connect said
rod to the treadle Q, of the sewing machine.
When the rod P, is depressed, it moves the lever L, on its pivot, so as to
disengage tlie brake-shoe O from the friction-disk D; and cause the outer end of
said lever to engage rod K, and force the same inwardly, which results in the
engagement of the friction-disk J, with its companion, and the lateral displace-
ment of the armature relative to the field magnets. The shaft to be driven may
be controlled in its speed by increasing or diminishing the pressure of friction-
disk J. As the motor is designed to run continuously at a suitable speed,
friction-disk J is constantly rotating, and when rod P is depressed slightly, disk J
engages its companion under slight pressure, and said companion, meeting with
resistance, will permit the disk J, to slip thereon, so that, in the case of the power
being applied to a sewing machine, the needle may be caused to vibrate fast.or
slow as desired. When the machine being driven is to be run at full speed,
disk Jis pressed tightly against its companion, so that the two run practically
in unison. When the machine, is to be stopped, pressure is relieved from rod P,
and lever L, and spring N causes the outer end of said lever to move outwardly,
and the inner end of said, lever to move upwardly, which latter carries its brake-
shoe into contact with the disk D, causing the machine to cease running. The
stoppage of the machine, while materially assisted by the brake-shoe, is, in
reality, dependent upon the disengagement of the live disk J from its companion,
and to cause this disengagement dependence is placed on the magnetism of the
field magnets of the motor for withdrawing the armature back into place, and
consequently moving disk J away from its companion. This magnetism, it has
been found, can be entirely relied upon to accomplish this disengagement without
resort being had to levers, weights or springs. The lateral displacement of the
armature by positive mechanical means, and the restoration of the armature to
its normal position by magnetism, is considered novel, as it is not thought that
such has been done heretofore.
While there is shown. means for positively effecting lateral-displacement of
the armature and its carried friction-disk, to cause an engagement of the disk
with its companion, said armature being subsequently restored to its normal
position by magnetism, which disengages the active or live disk from its com-
panion, yet, it will be understood that this action can be reversed, and magnetism
relied upon to effect a longitudinal movement of the armature relative to its
shaft to cause the engagement of its disk with its companion, while mechanical

page_text: means can be resorted to, to effect the positive disengagement of disk J from its
companion.
In Figure 4 there is shown a slightly modified form of the invention, in which
a collar R is mounted on the fixed shaft, and against which the inner end of
sleeve H bears. This collar is engaged by a lever S, pivoted at s, and provided
with a projection s', which extends through a spring N1, corresponding in nature
and function to spring N, shown in Figure 1, said projection s', being engaged by
the outer end of lever L, as heretofore described. The operation of the motor
here shown is similar to that described, with reference to construction, shown in
Figure 1, the only difference being the substitution of lever S for the rod K.
In Figure 5 there is shown a construction in which the armature is mounted
on a solid shaft H, slidingly mounted in suitable bearings, and against which shaft
the outer end of lever L bears.
Minor changes in the arrangement, construction and combination of the several
parts of the device can be made and substituted for those herein shown and
described, without in the least departing from the nature and principle of the
invention.
.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondents, I declare that what I claim is:
1. The combination with an electric motor which is normally in circuit, of
mechanical means for laterally displacing the armature of said motor relative to
its field magnets, the magnetism of said field magnets being relied upon to restore
said armature to its normal position upon the disengagement of said mechanical
means therefrom; substantially as described.
2. The combination with an electric motor, in which is included an armature,
slidingly mounted on or in its bearings, and means for positively thrusting said
armature longitudinally along its bearings, so as to displace the same laterally
with reference to its field magnets; substantially as described.
3. The combination with an electric motor, comprising field magnets, and an
armature whose shaft slides longitudinally, a clutch member carried by said
armature shaft, and positive mechanical means for moving said armature shaft
and its carried parts longitudinally in one direction, the magnetism of the field
magnets restoring said armature to its normal or free running position; sub-
stantially as described.
4. The combination with an electric motor, comprising field magnets and an
armature which is mounted on a longitudinally movable shaft, of a clutch member
carried by said shaft, a companion clutch member mounted on the shaft to be
driven, and which is engaged by the motor clutch member, and a lever for moving
said armature shaft and its carried parts longitudinally; substantially as described.
5. The combination with an electric motor, comprising field magnets, and at
armature mounted on a longitudinally movable shaft, of a clutch disk mounted
on said armature shaft, a companion clutch disk, with which said first mentioned
clutch disk co-operates, a lever for moving said armature shaft, and its carried
parts, said lever also carrying a brake co-operating with the clutch to be driven;
substantially as described.
6. The combination with an electric motor, comprising field magnets, and an
armature, which is mounted on a longitudinally movable shaft, a clutch member
carried by said armature shaft, a lever for moving said shaft longitudinally,
yielding means between said lever and said shaft; substantially as described.
7. The combination with an armature, of an electric motor, which is mounted
on a longitudinally movable shaft, of a clutch disk carried thereby, a companion
disk mounted on the shaft to be driven, and axially in line with the armature
shaft, a lever for positively engaging the armature shaft for moving the same in
one direction, and means for restoring said lever to its normal position; sub-
stantially as described.

page_text: 8. The combination with an electric motor, comprising field magnets and a
laterally displacable armature, a clutch member, which is controlled by said
armature, a lever for positively displacing said armature in one direction, the
magnetiam of the field magnets being relied upon to restore the armature and
its associate parts to their normal position, a driven clutch co-operating with the
armature clutch, and a brake co-operating with said driven clutch whenever the
armature clutch is disengaged therefrom; substantially as described.
9. The combination with lever L, of a spring for restoring the same to its
normal position, and adjustable spring pressed' plug carried by said lever, and an
armature provided with mechanism yieldingly engaged by said spring pressed
plug, whereby, when said lever is actuated, said armature is laterally displaced
relative to its field magnets; substantially as described.
10. The combination with a shaft to be driven, of an idle clutch member mounted.
thereon, a motor,, whose armature carries a live clutch member, a lever for posi-
tively engaging said live clutch member with its idle companion, a brake-shoe
on said lever which co-operates with said idle clutch member, a rod connected
to said lever, and a treadle to which said rod is. connected; substantially as
described.