Improvements in Means for Regulating the Speed of Tramcars and like Vehicles.
Year: 1896

page_text: Date of Application, 31st Dec., 1896
Complete Specification Left, 1st Nov., 1897-Accepted, 11th Dec., 1897
IONA
"Improvements in Means for Regulating the Speed of Tramcars and
like Vehicles.
I EUSTACE FITZMAURICE PIERS, Baronet, of 21 Lime Street in the City of
London, Mechanical Engineer, do hereby declare the nature of my Invention to be
as follows:
My Invention relates to tramears and like vehicles such as are described in the
Specification to Letters Patent granted to me and bearing date as of the 23rd day of
January 1895 No. 1623 and has for its object to provide improved means for
regulating the speed of the said vehicles.
According to my present Invention I provide in place of the screw regulating
device, described in the Specification herein before referred to for altering the position
of the crank pin from which the pumps are worked for supplying water to the
hydraulic engines, a cylinder and pistou carried by the crank shaft, the rod of
which piston may be connected to the adjustable crank pin and fluid under
pressure be admitted to the cylinder to either one side or other of the piston
according to the direction in which the crank pin is to be moved.
The fluid may be forced into the cylinder by a pump worked by the primary
engine or from any other suitable part of the car. Instead of connecting the piston
rod to the adjustable crank pin as described the piston may be stationary and the
adjustable crank pin be connected to the cylinder the said cylinder being movable
on the piston. Instead of the piston or cylinder being connected to the adjustable
crank pin as described an eccentric working the pumps may be rendered more or
less eccentric by the said regulating device so as to vary the stroke of the pump.
Dated this 31st day of December 1896:
JOHNSONS & WILLCOX
47 Lincoln's Inn Fields London W.C. Agents.
COMPLETE SPECIFICATION.
"Improvements in Means for Regulating the Speed of Tramcars and
like Vehicles:""
I EUSTACE FITZMAURICE PIERS, Baronet of 21 Lime Street in the City of London
Mechanical Engineer, do hereby declare the nature of this invention and in what
031

page_text: manner the same 'is to be performed to be particularly described and ascertained
in and by the following statement:-
My Invention relates to means for regulating the speed of tram cars and like
vehicles for which an arrangement is described in the specification of Letters Patent
dated: Jauuary 23rd 1895 No. 1623.
According to my present invention, in place of the sorew regulating device for
altering the position of the crank pin from which the pump is worked for supplying
water to the hydraulic engine, as described in the specification of the said Letters
Patent above cited, I work the pump by an eccentric which can be made more or less
eccentric by suitable adjusting means so as to vary as required the stroke of the
pump and thereby regulate the quantity of the water forced into the hydraulic
cylinder and correspondingly 'regulate the speed of the vehicle.
Figure 1 of the accompanying drawings is a face view and Figure 2 a section at
right angles to Figure 1 of an eccentric provided with convenient means according
to my invention for varying the eccentricity thereof by fluid pressure. Figure 3
represents in plan a portion of a tram car such as is shewn and described in the
specification hereinbefore referred to shewing my improved adjustable eccentric
applied thereto for working the pumps D by which water is forced into the hydraulic
engines for driving the car.
Referring to Figure 3, H is a shaft receiving rotation from the gas engine or other
prime motor carried on the vehicle. On the shaft H is mounted the eccentric A
constructed according to my invention as shewn in Figures 1 and 2.
On the shaft H, formed in one therewith or attached thereto, is a cylinder 'B
preferably of rectangular form on the exterior, and fitting a slot or opening C made
diametrically in the eccentric A, so that the said eccentric can slide upon the said
cylinder. In the cylinder B is a plunger E the outer end of which bears against one
end of the slot or opening C in the eccentric, and is held in contact therewith.by
Buid pressure admitted to the cylinder beneath the plunger, by a longitudinal
passage F'iu the shaft H communicating with the delivery end of a pump a operated
by a connecting rod a¹ hinged to the strap of the eccentric b by which the valve of
the pump D is operated. The pump a may however be operated direct from the
prime motor or by any other suitable means so that the plunger E can be forced
more or less from the cylinder B and so increase more or less the eccentricity
of the eccentric A and correspondingly lengthen the stroke of the pump D operated
thereby..
It will be understood that as the eccentricity is increased the quantity of water
forced into the hydraulic engines will be increased and consequently an accelerated
speed be given thereby to the vehicle.
By reducing the pressure of fluid in the cylinder B the plunger E will enter more
or less the cylinder B and the eccentric A following its movement will become less
eccentric to the shaft Hand so shorten the stroke of the pump D and' consequently
reduce the speed of the vehicle.
The pressure of water in the cylinder B can be regulated as required by means of
a valve d'in the water passage leading from the pump a to the said cylinder B, and
by means of a valve'd', the water in the cylinder B can be permitted to flow from the
cylinder back to the tank from which it is supplied.
By withdrawing the pressure of fluid from the cylinder B the eccentric A can move
into position on the said cylinder so as to be concentric with the shaft H and so stop
the action of the pump 1 and consequently as no water will then be forced into the
hydraulic engines the vehicle will stop.
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.
In combination with hydraulic engines for driving tramcars and other vehicles, and
pumps for forcing fluid into the cylinders of the said engines, of an eccentric for

page_text: working the pump and means for varying the eccentricity of the eccentric by fluid
pressure substantially as and for the purpose herein before described.
Dated this 30th day of October 1897.
JOHNSONS & WILLCOX
47 Lincolns Inn Fields, London, W.C., Agents.