Improvements in Apparatus for Ascertaining the Speed and Direction of Rotation of Engines, Shafting or the like.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Ascertaining the Speed and Direction
of Rotation of Engines, Shafting or the like.
I, JOSEPH ROBINSON, of 1, Skelbrook Street, Garrett Lane, Wandsworth, in the
County of Surrey, Engineer, do hereby declare the nature of this invention
to be as follows:
This invention, relates to that type of electrical counting mechanism, for ascer-
taining the number of revolutions of engines, shafting, or the like, in which the
apparatus remains inactive, until set in motion to ascertain the number of revolu-
tions in a small definite interval of time, and to record the same; and consists of
improvements, whereby the indicator pointer is brought to zero, by the same action
that winds the timing clock-gear and starts the indicator, and has a positive step
by step movement for recording, and is left locked in the position of the last
indication until brought to zero and re-started; and whereby a separate indication
of ahead" and "astern" is given, independent of the normal action of the speed
indicator and the whole apparatus is rendered cheap in manufacture and easy
to repair.
"
To carry my invention into effect I provide, upon a dial, a pointer, mounted on
an arbor, having a toothed wheel, driven by a pinion on a small counter shaft,
operated by a step-by-step positive motion from a reciprocating armature to electro
magnets, energized by a current, caused to be intermittent by a make-and-break
device, geared to or driven by, the engine or other shaft, whose speed it is desired
to record.
The said positive step-by-step motion from the reciprocating armature is obtained
by a star wheel on the counter spindle, which is operated by the end of the said
armature as a pawl finger, in combination with a roller mounted on the end of a
spring engaging also, as a lock and pusher, in another part of the star wheel.
The timing mechanism is of clock-work, with a disengaging pallet escapement,
having a movable weight upon the pallet to adjust the speed of the clock-work, such
escapement being designed to start immediately under the pressure of the main
spring, without any auxiliary impetus to the escapement.
The make-and-break operating current to the step-by-step electro magnets, passes
by insulated spring brushes over the main drum of the clock-work mechanism, and
the said intermittent current is completely broken when the said drum has com-
pleted the one revolution for which it is timed, and the apparatus ceases to count
until restarted and rewound.
The spindle of the indicator pointer has a frictionally-held mitre wheel, engaging
with a mitre wheel having a gap in its toothed circumference, fixed upon the
winding arbor of the clock-work drum.
Stops are provided, checking the clock, after the main drum has completed one
revolution in a known exact time.
When it is desired to re-start the counter, the first movement of the drum arbor
of the clock-work engages the friction-held mitre wheel of the indicator pointer

page_text: 1
spindle, so that the latter is brought back against a stop to zero, when the friction-
held mitre wheel slips, until the clock arbor has made a complete turn and releases
the clock-work mechanism to make its defined time run. At the same time the gap
on the drum-arbor mitre-wheel allows the indicator arbor and its friction-held
mitre-wheel to move freely in that gap, by the reciprocation of the armature of
the electro-magnets under the make-and-break current, completed through the
clock-work drum as a commutator, from the make-and-break device, geared to
the shaft, whose revolutions have to be counted.
"
The said make-and-break device, is characterized by the contact switch being
held rigidly over, in the position either of "ahead' or astern as the case may
be, and making a specific side spring contact in either of those positions; and
also the said contact-arm finds a recess in the periphery on which it rests, which
permits the said arm to change its side contact and position for either direction
of rotation of the drum, geared to the shaft, whose revolutions have to be counted.
The side contact of the said contact switch, of which one only can be closed
at one time, determines a shunt current around one or other of two electro-
magnets, having an armature pivotted between them, so that a pointer or other
indicator, on the pivot of such armature, will indicate in what direction the revolu-
tions may be, according to which of the pair of electro-magnets is energized.
Dated this 10th day of May 1898
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.
Improvements in Apparatus for Ascertaining the Speed and Direction
of Rotation of Engines, Shafting or the like.
I, JOSEPII ROBINSON, of 1, Skelbrook Street, Garrett Lane, Wandsworth, in the
County of Surrey, Engineer, 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 :-
www
This invention relates to that type of electrical counting mechanism for ascer-
taining the number of revolutions of engines, shafting, or the like, in which the
apparatus remains inactive, until set in motion to ascertain the number of revolu-
tions in a small definite interval of time and to record the same; and consists of
improvements whereby the indicator pointer is brought to zero, by the same action
that winds the timing clock-gear and starts the indicator, and has a positive step
by step movement for recording, and is left locked in the position of the last
indication until brought to zero and re-started; and whereby a separate indication
of "ahead" and "astern" is given independent of the normal action of the speed
indicator, and the whole apparatus is rendered cheap in manufacture and easy
to repair.
To carry my invention into effect I provide upon a dial a pointer mounted on
an arbor having a toothed wheel driven by a pinion on a small counter shaft
operated by a step by step positive motion from a reciprocating armature of electro
magnets energized by a current caused to be intermittent by a make and brake
device geared to, or driven by, the engine or other shaft whose speed it is desired
to record.
The said positive step by step motion from the reciprocating armature is obtained
by a star wheel on the counter spindle, which is operated by the end of the said

page_text: armature as a pawl finger in combination with a roller mounted on the end of a
spring engaging also as a lock and pusher on another part of the star wheel.
The timing mechanism is clock work, with a disengaging pallet escapement,
having a movable weight upon the pallet to adjust the speed of the clock work, such
escapement being designed to start immediately under the pressure of the main
spring, without any auxiliary impetus to the escapement.
The make and brake operating current to the step-by-step electro-magnets, passes
by insulated spring brushes over the main drum of the clock work mechanism and
the said intermittent current is completely broken when the said drum has com-
pleted the one revolution for which it is timed and the apparatus ceases to count
until restarted and rewound.
The spindle of the indicator pointer has a frictionally held mitre wheel, engaging
with a mitre wheel having a gap in its toothed circumference, fixed upon the
winding arbor of the clock work drum.
Stops are provided checking the clock after the main drum has completed one
revolution in a known exact time.
When it is desired to restart the counter, the first movement of the winding
drum arbor of the clock work, causes the gapped mitre wheel thereon to engage
the friction-held mitre wheel of the indicator pointer spindle, so that the latter
is brought back against a stop to zero, when the friction held mitre wheel slips
until the clock arbor has made a complete turn and releases the clock work mechan-
ism to make its defined time run. At the same time the gap on the drum arbor
mitre-wheel allows the indicator arbor and its friction held mitre-wheel to be
moved freely in that gap, by the reciprocations of the armature of the electro-
magnets under the make and break current, completed through the clock work
drum as a commutator, from the make and break device geared to the shaft whose
revolutions have to be counted.
The said make and break device is characterized by the switch being
held rigidly over in the position either of "ahead" or
astern" as, the case may
be and making a specific side spring contact in either of those positions; and
also the said contact arm finds a recess in the periphery on which it rests, which
permits the said arm to change its sides contact and position for either direction
of rotation of the drum geared to the shaft whose revolutions have to be counted.
The side contacts of the said contact switch of which one only can be closed
at one time, determines a shunt current around one or other of two electro
magnets, having an armature pivotted between them so that a pointer
indicator on the pivot of such armature will indicate in what direction the revolu-
tions may be, according to which of the pair of electro-magnets is energised.
or other
And in order that my invention may be the better understood I will now proceed
to describe the same reference being had to the drawings annexed and to the letters
and figures marked thereon.
Fig. 1 is a diagrammatic view of the general arrangement of circuits in the
apparatus.
Fig. 2 is a back view of the recording dial and
Fig. 3 is a front view of the dial showing indicating pointers.
Fig. 4 is a front elevation and
Fig. 5 a side elevation of the commutating or make and break device operated
by the engine or shafting.
Figure 6 is a detached and enlarged detail of the segmental cog gearing for
bringing the pointer back to zero.
Fig. 7 is a front elevation and
Fig. 8 a side elevation of the timing clock mechanism and
Fig. 9 is an elevation of the internal part of the same with the front plate
removed.
In the diagrammatic view, A is the recording dial, B is the battery, and C is
the commutator or current make and break device, driven by the engine or shaft-
ing whose speed of revolution it is desired to indicate. D is the timing clock

page_text: 6i
work on the recording dial. E is the electro-magnetic step by step driving device
and F are a pair of electro-magnets operating an indicating pointer as to the
direction of the revolutions, such as forward" or astern in a steamer.
Upon the dial A is provided a pointer a of which the arbor a carries a toothed
wheel G, Fig. 3, fixed to the arbor engaging by a pinion g and a star toothed
ratchet wheel g¹ Fig. 2 on the same counter shaft, with the step by step driving
device E. The arbor a also carries a bevel pinion a², Fig. 6, frictionally held
on the said arbor, by which from the rotation of the segmental bevil wheel H,
Figs. 2 and 6, gearing therewith and which is on the winding arbor h of the timing
clock work D, the said pointer a is brought back to zero as hereinafter more
fully described, after an observation as to speed has been indicated and finished.
The speed indication of the pointer a is produced by the number of step by step
movements of the star toothed ratchet wheel g¹ under the influence of a current
from the battery B which is made and broken for each revolution of the com-
mutator C, driven in exact ratio to the engine or shafting whose speed it is desired
'to count and indicate, and such indication is limited as to time by the clock-work
mechanism D which completely disconnects the electric circuit at the end of a
definite period of revolution, such as a minute.
The electrical circuit is first closed by the spring tongues d d which rest upon
the metal of the spring drum d, Figs. 2 and 9, when the latter is' in motion, and
break the circuit by standing over a recess when the drum has completed one
revolution and is there locked, until rewound by the handle h¹ for the next
observation.
The current passed through such circuit is made and broken once for each
revolution of the commutator C. This commutator is driven from the engine or
shafting whose speed it is required to test by a pulley c which may either be
part of the commutating disc K or may run loose therefrom and be connected
thereto, by a spring pressed pin or other connection' put in action electrically by
the current when completed through the drum of the clock work mechanism. In
this latter case the pulley c¹ when out of connection with the commutating disc K
will run loose leaving the disc K at rest except when required for indication.
The disc K, Figures 4 and 5, has a surface of insulating material such as ebonite
with a metal contact strip k upon it, in electrical contact with the side spring k¹,
and thus with one pole of the battery B.
A switch lever L is pivotted at 1, and presses by a spring underneath it upon the
face of the commutator disc K, making contact with the contact strip as the
disc revolves when in either of its oblique positions on either side of the perpen-
dicular, according to the direction of rotation of the disc K. The recess in
the hub of the commutator disc permits the switch L to be carried over by the
friction of the disc K to either of its alternative oblique positions according to the
direction of rotation of the disc. In one of these positions the switch lever L
makes side contact with the contact 11 on the one side in one direction of rotation
of the disc L and with the other contact 12 in the other direction of rotation.
The wires from these contacts pass through one of the two electro magnets f, f,
of the direction indicator F, the alternative circuits uniting afterwards to the
step by step electro-magnets of the device E which are in series.
Above the alternative electro-magnets f, f, of the device F is a pivoted arma-
ture f Figure 2, carrying on its pivot the direction-indicating pointer f³,
Figure 3, the arbor of this pointer being held from vibration or movement except
under the action of one or other electro-magnet f by a spring f³. The direction
of rotation of the engine or shafting is thus indicated.
The intermittent current thus passed to the electro magnets e e of the step-by-
step driving device E intermittently attracts the pivoted armature e¹ against the
recoil spring thus rotating the star-toothed ratchet wheel g¹ tooth by tooth,
the said wheel being held and steadied between each driving impulse by the
roller t¹, pressed against the wheel g¹ by its spring 12.
The indication of speed given by the dial pointer a, when the timing clock-
4
5
5

page_text: work D has come to rest, is thus held stationary in place indefinitely, until the
pointer is brought back forcibly to zero as follows:-
To set the apparatus into operation, the timing clock-work D is wound up
through one turn of the handle h¹, the winding arbor being checked at the end of
one turn by the pin 2 (Figure 8) of the winding arbor, coming against the pin m
of the sliding piece M, when the latter is lifted as hereinafter described from its
lowest position, as shown to which it is allowed to fall by the pin m³, (Figure 7)
of that sliding piece M, and which projecting within the frame, by a bent arm falls
into a slot n of a disc N, upon which the bent arm of the pin m¹ otherwise rests.
Fig. 8 shows the winding arbor h free to be again rewound after the completion'
of an indication.
Upon winding up the spring within the drum d' the said drum begins to revolve,
the escapement wheel P, and pallet p, being so constructed that motion ensues
at once, the timing of the escapement action being conveniently controlled by the
adjustable weight 2 on the lever p² of the pallet arbor.
At the same time a cam Q upon winding arbor h of the drum d¹, Figure 9
passes under the nose of the lever R which lifts the sliding piece M and its pin m²
out of the recess n³ of the disc N allowing the drum to start, and raises the pin m
of the sliding piece M into such a position as to check the winding arbor by the
pin 2, when it has made one turn, and the winding arbor is also locked from return
by the pawls at the back Fig. 7. As the drum d' commences to revolve it holds
up the nose of the lever R, and consequently the sliding piece M, by the pin n³
on the drum d to prevent the pin m' of the sliding piece M from falling again into
the recess n of the disc N. When this recess has travelled out of range, the
pin m rests on the edge of the disc N, until the revolution of the drum d', for
which the clock mechanism is timed, has been completed. The sliding piece M
then falls with its pinim¹ into the recess 2 of the disc N, and locks and arrests the
timing apparatus until re-wound, whilst at the same time the contact springs d d
which have closed the electrical circuit during the revolution of the drum break
the circuit by coming opposite to the recess of the drum, and the pointer a
of the dial A, stopping and being held at its then position of indication of speed,
the indication is complete and finished.
The winding arbor of the clock-work mechanism, carrying the segmental
bevel wheel H, gears into the frictional bevel pinion a² of the arbor a of the
pointer a and brings the latter back to zero, at which position the pointer is checked
by a pin g² fixed on the wheel G meeting a pin g³ fixed on the dial.
As the distance through which the pointer may have to be returned to zero,
varies with each observation, the cogged part of the bevil-wheel H is sufficient to
carry the pointer back through a maximum distance, hence the pinion is only
frictionally held on the arbor a¹, sufficiently tightly to overcome the resistance
of the holding spring roller t, but easy enough to slip when the pointer is checked
at zero by the aforesaid pins g² g³.
The segmental bevel wheel H comes to rest when the winding turn has been
finished so that the pinion a² lies in the gap of the said segmental wheel, and the
arbor of the pointer a is not retarded in any way during its electrically driven
step by step movement for indication.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is --
1st. In a speed and direction indicating apparatus, the combination with a
time-mechanism winding arbor of a segmental bevel wheel thereon, engaging
during a part of its revolution with a frictionally held pinion upon the pointer
arbor, to bring the pointer back to zero upon rewinding the time mechanism for
a fresh observation, substantially as described.
2nd. In a speed and direction indicating apparatus, the combination of a dial
pointer, and cog gearing of a star toothed driving wheel a reciprocating armature

page_text: to intermittently energized electro magnets for driving step-by-step the said
star-toothed wheel, and a spring-held arresting and locking roller, engaging
between the teeth of said star-toothed wheel, to arrest and lock the indicating
pointer in last position of indication until the apparatus is re-wound, substantially
as described.
3rd. In a speed and direction indicating apparatus, a pivoted switch tongue,
to a rotary commutator, making alternative contact to either side, according to
the direction of the rotation of such commutator, in combination with two electro-
magnets, energized alternatively, from either one of such switch contacts of
the commutator, and a rocking armature above such electro-magnets, having an
indicator pointer on the pivot of the same, to indicate in one of two alternative
positions the direction of rotation of the engine or shafting to be indicated,
substantially as described.
4th. In a speed and direction indicating apparatus the combination with a clock-
work mechanism of a disengaging pallet escapement controlled by an adjustable
weight, and a locking device; whereby only one turn of the winding arbor, and
one revolution of the spring drum can be effected for one observation, and of means
by which the operative electrical circuit to the indicating apparatus is first made
and then broken by one revolution of the spring drum, substantially as described.
5th. The combination and arrangement of electrical circuits and parts forming
a speed and direction indicating apparatus substantially as described and illus-
trated in the drawings annexed hereto.
Doted this 7th day of Fabvuonn 1800
FELL & JAMES,
1, Queen Victoria Street, London, E.C.,
Agents for the Applicant.