Improvements in Apparatus for Indicating Speed of Revolution of Parts of Machinery.
Year: 1886

page_text: Improvements in Apparatus for Indicating Speed of Revolution of
Parts of Machinery.
We THOMAS FERDINAND WALKER of the firm of Thomas Walker & Son of
58 Oxford Street Birmingham in the County of Warwick, Engineer, and JAMES
GEORGE WATERS FAIRBAIRN of 4 Grange Road Small Heath Birmingham aforesaid
and in the employment of the said firm, Electrical Engineer do hereby declare the
nature of this invention to be as follows:-
These improvements relate to means or apparatus for indicating the speed of
revolution of parts of machinery such as for instance the speed of revolution of the
shaft of a dynamo electric machine or generator of electricity.
Attached to the revolving part whose speed of revolution it is desired should be
indicated, is attached, say by a tapped hole therein engaging a screwed stud on the
applied part, a part stem or axis which revolves with the main axis. On this part
axis are hinged arms carrying balls or weights which again are linked to a collar or
sleeve sliding on the part axis. Between the arms carrying the balls and the sleeve
carrying the connections to the links is applied a spring or distending part giving a
normal tendency to separate to those parts whilst the flying outwards of the governor
balls or weights tends to compress the spring and bring these parts together. The
movements of this sliding sleeve are by means of a circular part held between
collars or projections connected to or formed on the sleeve conveyed by linked and
centred levers or arms to an index which parts are slung on the part axis but do not
partake of its rotatory movement, the circular part reciprocating but not revolving and
the lever part connected to it being connected by pins on the circular part engaging
slots in the lever or by arrangements equivalent thereto.
It is preferred to encase the governor revolving parts with an annular or dished
cover.
101
WM. BROOKES & SON,
55 & 56, Chancery Lane, London,
Agents for the said
Thomas Ferdinand Walker and
James George Waters Fairbairn.

page_text: COMPLETE SPECIFICATION.
Improvements in Apparatus for Indicating Speed of Revolution of
Parts of Machinery.
We THOMAS FERDINAND WALKER of the firm of Thomas Walker & Son of
58 Oxford Street Birmingham in the County of Warwick Engineer and JAMES
GEORGE WATERS FAIRBAIRN of 4 Grange Road Small Heath Birmingham aforesaid
and in the employment of the said firm Electrical 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 :-
These improvements relate to means or apparatus for indicating the speed of
revolution of parts of machinery such as for instance the speed of revolution of the
shaft of a dynamo electric machine or generator of electricity.
Attached to the revolving part whose speed of revolution it is desired should be
indicated is attached, (say by a tapped hole therein engaging a screwed stud on the
applied part) or the part axis may have a tapped collar or socket to slip over the
end of the shaft, a part stem or axis which revolves with the main axis, or other
convenient means of attachment may be employed; or the connection between parts A
and B may be merely frictional and temporary by the part B being formed as a coned
central stem, and being pressed for the time being against a correspondingly formed
recess in the end of A, the instrument being held in the hand by the indicating
mechanism end or by a handle provided thereto for the purpose. On this part axis
are hinged arms carrying balls or weights which again are linked to a collar or sleeve
sliding on the part axis. Between that part of the axis whereon are attached the
hinges of the arms carrying the balls and the sleeve carrying the connections to the
links is applied a spring or distending part giving a normal tendency to separate to
those parts whilst the flying outwards of the governor balls or weights tends to
compress the spring and bring these parts together. By means of a circular part
held between collars or projections connected to or formed on the sleeve, the
movements of this sliding sleeve are conveyed by linked and centred levers or arms
to an index which parts are slung on the part axis but do not partake of its rotary
movement during the time that the indicator is being consulted, the circular part
reciprocating but not revolving and the lever part connected to it being connected
by a pin or pins on the circular part engaging slots in the lever or by arrangement
equivalent thereto.
It is preferred to encase the governor revolving parts with an annular or dished
cover, or cylindrical casing.
DESCRIPTION OF THE DRAWINGS.
Figure 1 indicates by sectional view and Figure 2 by external view of the same one

page_text: by means of a screwed stud a forming part of the part axis B, taking into a tapped
hole a¹ in the shaft A. This shaft B revolves with the main shaft A. On the
enlargement b of the axis B are hinged at c¹ short arms carrying balls or
weights c which again are linked by links d² connected at d¹ to the balls c and
at d³ to a collar or sleeve d sliding on the shaft or axis B. Between the enlarge-
ment 6 on the axis B and the sleeve d carrying the links or connections d² is
applied a spring e or equivalent distending means adapted normally to press apart
those parts whilst on the other hand the flying outwards of the governor balls c
under the influence of an abnormally high rate of revolution of the part A tends
to draw the connections d², c² and bringing the parts c and d nearer together
compresses the spring e.
fis a block or part held between collars g, h, on the sleeve d to which any
movements of the sleeve d in the direction of the length of the axis B are
conveyed but not its rotatory movement. i is an index device to which any
Inovements of the block or part f are transmitted and indicated by the finger i.
These movements of the block fare conveyed by the arm 94 pinned to the part f
at g and centred to the index frame k at k¹ whilst its other end g' is linked at g2
to the arm g³ of a quadrant or it may be a straight tooth bar, operating a pinion
on the axis of the index finger i. k² is a part of the index framing slung on the
axis B but not rotating with it k³ is a recess for lubricant.
Figure 3 by side view and Figure 4 by plan shew another form of our invention
according to which the speed indicator is applied in a similar manner to a shaft
or part A whose speed of rotation is to be indicated. In this modification the
arm 9 is pinned or centered to the part fat g' to the index frame at k¹ and to
the sliding bar m at g² which bar being toothed moves the index tooth wheel and
index. The weight serves by its preponderance to keep the index portion i
stationary and resist tendency to partake of the rotatory motion of the shaft A,
instead of the whole index parts forming the retarding weight. The parts otherwise
are substantially the same in this as in the previously described arrangement. This
weight can be adjusted by the set screw / so as to exercise more or less leverage
or it may be turned up towards or under the indicator case so as to adjust the
angle of the indicator face. Figure 3ª shews by a section through the part axis .B
the form of the block f and collar h.
Figure 5 shews a modification in the form and arrangement of the arms carrying
the weights c.
A is the main axis B the part axis as before on which is formed a
collar b carrying the axial pins or centres 6' on which are hinged or centred arms c²
carrying weights or balls c which weighted arms are linked to a collar or sleeve d
sliding on the part axis B.
Between the enlargement or it may be a fixed collar 6 carrying the centre pins or
pivots of the arms c² carrying the weights c and the sleeve d carrying the connections d³
to the links d² is applied a spring e or equivalent distending part giving to the part d
normally a tendency to separate from the part b, and to draw the weights c closer to
the centre line of the part axis B.
The movements outward of the collars g, h under the influence of the spring e when
extending itself or inward when the centrifugal motion developed at increased speed
of the balls c overcomes the spring e will be communicated by means of the block to
the sliding arm or bar m carried with capability of sliding in the bearings m¹ and
this sliding motion by means of a rack cut at a is communicated to a pinion r¹ and to
a pointer carried by the same axis and thereby indicating on a dial in the ordinary
and well understood manner, the speed of rotation imparted to the axis A.
In the arrangement shewn by Figure 6 the same parts are employed as in Figure 5
and the same arrangement substantially is employed except that only one pair of cross
arms 2 is used and one pair of balls or weights c linked to the part d by links d².
Figure 7 is an end view shewing the arrangement of the single pair of arms c³,
weights c and links d² shewn in the previous Figure 6.
In place of the pair of arms in Figure 6 one central arm may be employed
working in centres arranged in a slotted opening through the part axis B and having

page_text: a weight or weights at its ends and these weights can be slidden on this arm to or
from the centre and be adjustable by set nut or like adjustment. The spring instead
of being applied centrally on the stem B may be connected to any convenient part of
the axis B and to the arm or arms or a part connected thereto.
Figures 8 and 9 shew by section and partly sectional side view respectively in two 5
positions and Figure 10) by external view a modification of the arrangement of spring e
from the previously described arrangement, particularly adapted to cases where a
greater length of movement of the sliding sleeve d is desired and to enable a greater
length of spring e to be employed to give a normal tendency to separate between the
parts and d. In this arrangement the part 62 on which arms c² carrying the 1
weights c are hinged is a sliding collar or sleeve and to this the arms c³ are centred
at b and these arms c³ carry the weights c whilst the links d' d' are each connected at
their outer ends to the arms c² c² and at their opposite ends respectively to the fixed
portion b of the part axis B and to the sliding sleeve d.
The distending spring is placed inside the cavity B' formed in the part axis B 1
and works therein as in a tube pressing against the end B2 as an abutment and against
the internal sliding block B3 from which block a pin B protrudes, through the groove
or slot B which pin passes into and forms a connection with the sliding collar d which
collar d engages and operates the block / connected to the sliding arm m of the
indicating mechanism as already described.
In Figure 8 in section are shewn the parts with the weights c in their normal
position of rest with the spring exercising its fullest powers of distention of the
links apart.
In Figure 9 is shewn the external appearance of the parts (except that the case is
shewn in section) when the balls and spring take the position due to the centrifugal
force developed at the highest speed of rotation recordable. It will be seen that
owing to the fact that the centres b₁ of the arms c² travel down, the actual distance of
movement of the sliding sleeve d is doubled thus securing increased accuracy and
sensitiveness to the indicator.
'
Figure 10 is an external view in plan of Figure 9 shewing the form of the external
case or cover n for shielding the contained mechanism.
If it be desired still further to increase the length of internal spring e this may be
effected as shewn in detail view Figure 11 by substituting for the solid sliding
block B³ a hollow tubular sliding part B attached by the pins (7) to the sliding
collar or sleeved so that the spring e may be almost the entire length of the main
tube B' of the part axis B and the fixed abutment end B2 of this tube shewn in
Figures 8 and 9 may be replaced by a screw plug B8 see Figure 12 capable of being
screwed in or out or so as to shorten or lengthen the case for the spring e and so
adjust the tension of that spring e.
This spring e may be applied in a variety of ways and yet serve the like purpose
and the mode of effecting the connection to the dial work as well as the relative
position of the dial may be varied provided that the dial is suitably attached to or
slung on the part axis B so that it will not partake, or can be conveniently
prevented from partaking of the rotatory movement during the time the register
is being referred to in order to ascertain the speed of the part A whose rotation
is being indicated.
In practice it is often found convenient to allow the whole to rotate so as to
save wear and tear of the frictional part such as between the sleeve d and the
part engaging it, or between the index frame and that part of the axis on which
it is slung and only during the time necessary for reference to make the indicating
part remain stationary.
When it is thought desirable to be able to throw the dial work out of gear
with the parts operating it this may be effected by arranging the connection
between the dial work and the block or part for other like part working between
the flanges of the sliding sleeve. d so that the said block or part may be introduced
or drawn out from between such flanges g, h for example by means of a jointed
arm f. f.

page_text: Figure 13 shews such a jointed connection in the armƒƒ¹ with the part ƒ engaged
in the groove between the flanges g. and h.
Figure 14 shows this part f folded back out of connection.
Or this engagement and disengagement of these parts may be effected by a sliding
movement as indicated by Figure 15 the dotted lines indicating the block or part f
engaged, and the full lines that part withdrawn by sliding the supporting stem in
the slide or bearing in the arm m.
By means of a spring the block fƒ may be kept normally out of the groove between
the flanges g, h except when reference to the index is required.
Or the block or part of working between the flanges g, h, may be replaced by a
forked connection f the prongs f³ of which embrace the edge of a disc or circular
plate d' attached to the sliding sleeve d as shewn by Figure 16.
As a further means of adjustment the balls or equivalent forms of weights may
slide or be moveable inwards towards or outward from the centre upon their supports
and be capable of being set by screws or otherwise.
By providing a pinion a¹ of size proportioned to the desired distance of travel of
the sleeve d the dial work may be so arranged that the indicating finger ¹ shall
make one, two, or more revolutions the dial having one, two or more correspondingly
graduated circles as shewn by Figure 17 with a sliding index o protruding through
the slot o¹ in the dial i and moved by the rack which index by preference we attach
directly on to the rack m to indicate from which circle 1, 2 or 3 the speed should be
ascertained.
Having now particularly described and ascertained the nature of our said
Invention, and in what manner the same is to be performed, we declare that what we
claim is :-
1. The combination or arrangement of parts of apparatus for indicating the speed
of revolution of parts of machinery substantially as set forth and shewn in
Figures 1, 2, 3, and 4 of the drawings.
2. The combination or arrangement of parts of apparatus for indicating the speed
of revolution of parts of machinery substantially as set forth and shewn in Figures 5
and 6 of the drawings.
3. The combination or arrangement of parts of apparatus for indicating the speed
of revolution of parts of machinery substantially as set forth and shewn in
Figures 8, 9, 10, 11, and 12 of the drawings.
4. The arrangement or combination of parts for connecting and disconnecting the
indicating mechanism to or from the reciprocating sleeve d as shown and described
with reference to Figures 13, 14, 15 and 16.
5. The arrangement or combination of parts for operating the indicating means of
apparatus for indicating the speed of revolution of parts of machinery as set forth.
6. The arrangements of parts and mode of operating the pivotal arms weights and
connections thereto for moving the indicating mechanisin as set forth.
Dated the 13th day of June 1887.