Improvements in and relating to Speed, Distance, and Gradient Indicators.
Year: 1898

page_text: .
PROVISIONAL SPECIFICATION.
Improvements in and relating to Speed, Distance, and Gradient
Indicators.
I, HAROLD EDWARD SHERWIN HOLT, of The Grange, Farnborough, in the County
of Hants, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:-
In motor cars I make an apparatus to shew the actual rate of progression at any
moment, the number of miles travelled and the gradient of the road. My speed
indicator consists of any suitable type of the well known engine governors or speed
indicators, acting through multiplying gear on a pointer. The distance meter
employed may be any of the well known varieties of cyclometer. I actuate the
cyclometer and the speed indicator by one flexible shaft connected with one of the
carriage wheels either by pulleys and belt, or gear wheels, or any convenient
method. Between the flexible shaft and the speed and distance meters I insert a
pair of pulleys and belt, or gear wheels, the ratios of which may be readily varied
according to the diameter of the carriage wheel.
My gradient meter consists of a pivotted arm controlled by a weight acting ver-
tically. Connected with the long arm through a spiral spring is a multiplying
lever the long end of which forms the pointer. A very slight movement of the
weight due to slight "tilting" of the apparatus, will cause a considerable move-
ment of the pointer. Hitherto gradient meters have been unsatisfactory on motor
cars owing to the shake of the motor car causing so much vibration of the pointer
that the gradient cannot be read with any accuracy. To obviate this I employ a
small glycerine dash pot connected with either the primary or secondary lever and
I further connect the two levers through a small spiral spring. In place of this
weight and lever I can employ a tube bent to semicircular form and partially
filled with mercury. Resting on the two surfaces of the mercury, are the two plate
like ends of a semicircular lever pivotted above the tube. The tube is rigidly
attached to the frame, and accordingly any tilting of the frame will cause an
alteration in the levels of the mercury in the two limbs of the tube. The two arms
of the lever being balanced, the mercury rising in one limb of the tube will force
up that arm of the lever as fast as the mercury descends in the other limb. This
lever actuates a pointer through multiplying gear. Dividing the tube into two
equal lengths is a partition with a small hole through which the mercury can flow.
This acts as a dash pot to prevent the mercury jumping up and down too suddenly
with every alteration in level.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to Speed, Distance, and Gradient
Indicators.
1.31
ד་
I, HAROLD EDWARD SHERWIN HOLT, of The Grange, Farnborough, in the County
of Hants, 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:-
This invention relates to speed, distance and gradient indicators for use on
vehicles, and has for its object to provide mechanism that shall be sensitive and
accurate in operation, and that shall not be subject to the vibration consequent
upon the movement of the vehicle.
::
The invention consists of a speed indicator which derives motion from some
moving part of the vehicle or actuating motor through a flexible shaft, and in
which a pendulum governor is caused to operate the indicating finger and a dash-
pot is employed to prevent unsteadiness of the finger as the result of vibration of
the car or change of speed. The invention further consists in the combination of
such a speed indicator with a distance indicator or cyclometer and the further
combination with a gradient indicator so arranged within one common casing as to
indicate distance, speed and gradient upon scales or through apertures provided
upon an exterior face. The invention also consists of a gradient indicator in which
unsteadiness of the indicating finger is avoided by the employment of a dashi-pot or
dash-pots or equivalent as hereafter described.
The invention is illustrated in the accompanying drawings; in which
Figure 1 is an exterior view of a casing in which speed, distance and gradient
indicators are provided according to the invention.
Figure 2 is a rear view having ilie back cover or door removed.
Figure 3 is a part sectional elevation of the speed and distance indicating.
mechanism on the line xy (Figure 2), while
Figure 4 is a sectional elevation of the gradient indicating mechanism on the
line y (Figure 2) looking from the speed and distance indicating mechanism.
(Figure 3).
In carrying the invention into effect as illustrated in the accompanying drawing.
I provide speed, distance and gradient indicators with a casing B having a curved.
transparent face C of mica, glass or other material, and this casing I mount upon
the vehicle at any convenient place, preferably by means of a clamping screw D
fixed to the back plate or door E of the casing (Figure 3) and secure such casing
in any convenient position upon the vehicle frame; and I communicate motion
to the main spindle from which the speed and distance indicating mechanism
derive motion by means of a flexible shaft F whose extremity F is secured to the
projecting extremity 9 of the vertical shaft G by means of a longitudinally split
collar (Figure 3) which is bound upon the projecting extremity g of the ver-
tical spindle G by means of a nut f. This flexible shaft is secured to some con-
venient fixed part of the motor or vehicle frame by means of the boss H; and
motion is communicated to this flexible shaft from the motor or vehicle wheels by
means of a grooved pulley I fixed upon an inflexible spindle 2 to which the
flexible part is suitable secured.
:
By the provision of a flexible shaft for the communication of motion to the indi-
cating apparatus the attachment of the instrument to different types of carriage is 4
greatly simplified and can be easily carried out by a person without mechanical
; 1

page_text: skill, while further the, vibration of the motor or vehicle is not transmitted seeing
that the flexible shaft permits of free relative movement. The vertical shaft G
is mounted within the bearings J and J₁ respectively secured to the base part of
the casing and to a pillar or support ; by means of which the distance indicator
or cyclometer L is carried. Upon the upper extremity of the shaft G a worm G'
is provided which gears it with a worm wheel G2 provided upon the spindle of the
indicator or cyclometer L which may be of any ordinary or particular construction
so that the distance may be indicated and the figures may be viewed through an
aperture provided upon the curved face C of the casing.
A pinion M is provided at the lower extremity of the spindle G and immediately
beneath a fly-wheel N, such pinion gearing with a spur wheel M pivoted at m and
gearing with a toothed wheel M². loosely mounted upon a vertical spindle O. The
teeth of the spur wheel M¹ may be relatively wide as indicated to permit of the
spur wheel M² remaining in, gear notwithstanding the movement of which it is
capable for the purpose of disengaging it from the fixed plate O fixedly mounted
upon the spindle O. The spur wheel M2 effects the rotation of the shaft O
through projections m² mounted upon the upper face thereof, which projections m²
engage with correspondingly shaped holes or recesses provided in the fixed plate O¹.
The disengagement of these projections may be effected by means of a supporting
piece P secured upon a transversely mounted rod P¹ whose extremity projects upon
the outer side of the casing, and has secured thereto an operating finger piece P
which may be released from engagement with a stop P3 and thereby permit of the
supporting piece l' descending with the consequence that a spiral spring m
mounted upon the spindle O between the fixed plate O¹ and the spur wheel M²,
forces down the latter so that its projections m² disengage with the holes or recesses
in the fixed plate and thereby motion ceases to be communicated to the spindle O.
By such means the speed indicating mechanism operated through the spindle 'O
may be set in or out of operation at will. The spindle O is mounted in pivot
bearings oo and has mounted thereupon a pendulum of any convenient and suit-
able form. That illustrated consists of a fixed plate Q to which the pendulum
arms Rare pivoted at q. To the arms R links S are pivoted whose lower extremi-
ties carry a sliding collar T. Between this sliding collar T and' à fixed collar U
a spiral spring U is provided which serves to resist the outward tendency of the
pendulum arms on rotation. Adjacent to the pendulum sprindle a horizontal
cross shaft V is provided which is mounted in brackets VIV and is subject to the
action of a spiral spring V2 mounted thereupon which maintains a roller W pro-
vided at the extremity of an arm W₁ mounted upon the cross shaft V, in proximity
with the lower face of the sliding collar T so that on the upward movement of the
collar due to the increase of speed the arm W passes upwardly and on the descent
of the sliding collar T the arm W is depressed. Upon the cross shaft V the
indicating arm X is mounted and at the upper extremity a finger X is mounted
and is provided to move above a speed indicating scale X upon the face of the
casing. It will be seen that upon the rapid rotation of the shaft F the sliding
collar T upon the spindle O rises and the arm W₁ follows under the action of the
spring thereby effecting a corresponding movement of the indicating finger X¹
upon the speed indicating scale X²
Ο
For the purpose of preventing unsteadiness of the finger X as the result of
sudden change in the rate of motion or as the result of undue vibration of the car
a dash-pot is provided adjacent to or beneath the cross shaft V in which
glycerine or other liquid is employed and a piston and rod is provided and con-
nected to the shaft by means of a slotted arm V3 engaging a pin X provided upon
the upper extremity of the piston rod V5.
I provide a gradient indicator upon the other side of the casing, such indicator
consists of an indicating arm Z having at its extremity an indicating finger Z
5 whch passes over a gradient scale 72 on the face of the casing. The gradient
indicating finger Z pivots at and is provided at its opposite extremity with a

page_text: weighted arm Z³. A further arm Z is provided, and fixedly secured in relation
to the indicating finger Z, to the extremity of which a link Zis secured which
connects to one extremity of a pendulum lever Z pivoted at' z 'and 'having depend-
ing therefrom a pendulum weight Z by means of which the lever Ze is niaintained
in a horizontal position or in such position that the indicating finger Z deriving
motion therefrom shall indicate on the scale the amount of divergence from the
horizontal. In order to prevent the unsteadiness of the indicating finger 7, a
dash-pot or dash-pots Z Z may be provided within which pistons may work which
are secured to the respective extremities' of the pendulum lever Z. Glycerine or
other suitable liquid may be provided within such dash-pots for the purpose of
retarding unduly rapid movement and of preventing unsteadiness of the mech-
anism. A weight Z may be provided for the purpose of balancing the link Z".
I do not limit my invention to the employment of dash-pots for preventing the
unsteadiness of the indicating fingers Z or X as I may dispense with an inde-
pendent dash-pot and employ the weight itself to act as a damping device' in the
manner illustrated in Figures 5 and 6.
As illustrated in Figures 5 and 6 the indicating finger Z may be mounted upon
a spindle 1 within brackets 2 mounted upon the cover plate 3 of the casing 4
within which the pendulum weight 5 is mounted. The pendulum 5 is secured to a
spindle 6, one of whose extremities has mounted thereupon a tooth quadrant 7 in
gear with a pinion 8 mounted upon the spindle 1 to which the indicating finger Z
is also secured. Glycerine or other suitable liquid is provided in the casing 4
and serves to prevent unsteadiness of the indicating finger due to vibration of the
vehicle or sudden change in the gradient of the road.
Instead of employing a casing such as 4 I may employ a circular tube 9 which
may be filled with mercury or other such suitable liquid, and pistons or floats may
be provided and secured to the quadrant 7 by means of arms 10 on either side
thereof, so that on the change of level of the vehicle, the level of the two surfaces
in the tube will respectively rise and fall, thereby causing a movement in one
direction or the other of the quadrant 7 and a corresponding movement of the
indicating finger Z deriving motion through a pinion from the tooth quadrant 7
aforesaid.
A partition 11 is provided midway in the circular tube 9 within which a hole is
provided through which the mercury may pass from one limb of the tube to the
other its rapid movement being prevented by the restriction of the opening in the
partition, which also acts as a dash-pot to ensure the steadiness of the indicating
finger Z. Stops may be employed to determine the movement of the quadrant 7.
Instead of securing the extremity of the flexible shaft F to the extremity of
the spindle GI may secure it to the extremity of the spindle O which in that case
would project through the base similarly to the spindle G.
The distance indicator or cyclometer L could be dispensed with, as also could
the gradient indicator.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is;-
1. In speed and distance indicators for use upon vehicles, the employment of a
flexible shaft in the manner and for the purposes hereinbefore described.
4
2. The combination of speed and distance indicating mechanism, intermediate
gear through which motion may be communicated from one to the other, and a
Hexible shaft communicating motion from a moving part of the vehicle or actuating 5
motor substantially as herein before described.
3. In speed indicators such as hereinbefore described the employment of a dash-
pot or damping device for the purposes and substantially as described.
4. In gradient indicators such as hereinbefore described the employment of a
dash-pot or damping device for the purpose and substantially as herein before 5
'described.

page_text: 5. A combined speed and distance indicator substantially as hereinbefore
described and illustrated in Figures 1 to 4 of the accompanying drawings.
6. A gradient indicator substantially as hereinbefore described with reference to
Figures 4, 5, 6, and 7 of the accompanying drawings.
is 18th day or
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and
25, Cross Street, Manchester, Agents.