Improvements in or relating to Automatic Accumulator Switches.
Year: 1890

page_text: Date of Application, 20th Jan., 1890
Complete Specification Left, 20th Oct., 1890-Accepted, 29th Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in or relating to Automatic Accumulator Switches.
I, WILFRID SWANWICK BOULT, of 24 King's Mount, Birkenhead, in the County
of Chester, Civil Engineer, do hereby declare the nature of this invention to be as
follows:-
This switch is designed for use in connection with electric accumulators or
secondary batteries; its purpose being to maintain a nearly constant pressure in the
mains in connection with the accumulator by varying the number of cells of this
latter included in the electric circuit.
The motive power for actuating the switch is provided by weights, springs, or
motors, divided into two parts for working the switch in opposite directions, and
prevented from moving by two movable stops or pawls either of which may be with-
drawn by the movement of the core of a solenoid of high resistance placed as a shunt
across the mains.
Through the intervention of bevil gear or equivalent the movements of the two.
driving weights cause opposite rotations of a shaft the movement of which is trans-
mitted successively to a series of switch arms or equivalent for making contact with
successive cells of the accumulator.
A convenient construction of the whole apparatus is as follows:-
A main shaft or spindle is supported in bearings and carries two hollow shafts or
sleeves connected to the main shaft and each other by means of three bevil wheels
forming a Whites dynamometer or balance gear.
On each hollow shaft, in addition to one of the bevil wheels mentioned, are a ratchet
wheel with say three teeth (which for distinction I call ratchet wheel A), and a chain-
wheel, the latter carrying a chain, cord, or eqivalent suspending the driving weight,
and preferably mounted, as in a weight-driven clock, with ratchet arrangement for
winding. The ratchet wheel A is prevented from being turned by the weight by
means of the movable stop or pawl previously referred to governed by the solenoid
core. It may be held against rotation in the opposite direction by a ratchet and
pawl facing the reverse way. Thus the apparatus can be wound up without
trouble.
Beyond the hollow shafts, the main shaft carries disposed round it and at intervals
in its length a series of toothed sectors which as the shaft is rotated engage con-
secutively with corresponding sectors attached to as many separate tumblers. Each
tumbler supports a switch arm and is so arranged that at the middle of its throw the
arm is in its most depressed position, and electrical connection is established with
the corresponding accumulator cell.
The tumblers may be held in their extreme positions, and the switch arms be
depressed, by either weights or springs.
The action is as follows:-Suppose the difference of potential in the mains has
become too low. The solenoid core has moved accordingly, (say been lifted by a
spring), and raised one of the pawls; the main shaft is revolved by the corresponding
weight; the toothed sectors work the tumblers; one switch arm is lifted, and the
next one depressed, and one more cell is included in the circuit. The solenoid core
is now pulled down and the pawl engages with the next tooth of the ratchet A. If, in
charging, the potential difference becomes too high, the other pawl is lifted. the
shaft is rotated in the opposite direction and the number of cells in circuit is
reduced.
To allow the solenoid core and pawl to resume their normal position in time
or the latter to engage with the next tooth of the ratchet A, this last in revolving

page_text: draws out a second pawl which stops it in a proper position and releases it slowly,
being retarded by means of a dash-pot, fly, or equivalent retarding device.
Many modifications in the details of this apparatus are possible without departing
from the nature of my invention.
Dated this 20th 2CT
1000
COMPLETE SPECIFICATION.
Improvements in or relating to Automatic Accumulator Switches.
I, WILFRID SWANWICK BOULT, of 60 Castle Street, Liverpool, in the County of
Lancaster, 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 switch is designed for use especially in connection with electric accumulators
or secondary batteries; its purpose being to maintain a nearly constant pressure in
the mains in connection with the accumulator by varying the number of cells of
this latter included in the electric circuit so as to compensate for variations of electro-
motive force in the battery.
The motive power for actuating the switch is provided by weights, springs, or
motors, divided into two parts for working the switch in opposite directions, and
prevented from moving by two movable stops or pawls either of which may be with-
drawn, either directly or through the intervention of suitable mechanism, by the
movement of the core of a solenoid of high resistance as commonly arranged, or other
suitable pressure meter, connected as a shunt across the mains.
By means of bevel gear or equivalent the movements of the two driving weights
cause opposite rotations of a shaft actuating the contact-making arm or equivalent,
hereinafter referred to, together with the necessary contact plates or brushes, as the
"switch proper."
A convenient construction of the apparatus is shown in the accompanying drawings,
in which
Fig. 1 is a plan not including either the "switch proper," or the pressure-meter,
Fig. 2 a side elevation of the same, and
Fig. 3 a front elevation showing also a suitable "switch proper." (Fig. 4 is
described below.)
In these, B is the switch shaft, (capable of being rotated in either direction, as
explained above), held in bearings C, and partly encased by the loosely fitting sleeves or
hollow shafts shown by dotted lines in Figs. 1 & 2. Each sleeve carries rigidly
attached to it a bevel-wheel D, ratchet-wheel E, and three-toothed ratchet-wheel A.
A chain-wheel F runs freely between A and E, and carries a pawl G engaging
with the latter. F is thus free to move in one direction for "winding up
" without
turning the sleeve &c., while, in the direction of the arrow, it carries these latter
with it. A pawl H engaging with E permits motion only in the direction of the
Chains J engage with the wheels F which, by means of suspended weights,
they tend to turn with the arrow.
arrow.
In gear with the two bevel wheels D is a third one K carried by and free to
revolve on a stud or arm I proceeding from the switch shaft B.
M M are levers pivoted at the end M and having a slot or fork M¹ at the other
end. A projecting tooth M is formed to engage with ratchet wheel A, and a
shoulder M³ serves to lift off the pawl N.
O is a fixed shatt on which, free to revolve, are the two eccentrics P, the two
single-tothed ratchet-wheels Q, the two ratchet-wheels R. (in each case, P, Q, and R
being rigidly connected together), the two chain-wheels S, with pawls S₁, and the
large toothed wheel T carrying the two ratchet-wheels U. V, V are pawls engaging
with ratchet-wheels R. This arrange ent permits of the "winding up
" of chain S
as in a clock. Wheel T is in gear with pinion W and rotates fly X.

page_text: are pawls for holding wheels Q, carrying balance weights Y at one end and
lengthened out as shown at Y¹.
ZZ' is a lever for lifting the pawls Y', pivoted at Z and having its outer end Z¹
connected with the solenoid core above mentioned.
a, b, c, d, e, f, Fig. 3, are radial switch arins, spaced helically round the shaft B,
which as the latter rotates, make contact consecutively with brushes or plates a¹, a², b¹, b²,
&c. mounted on insulating posts g, h, i, j, k, l. Plates a, b, c, &c. are connected
directly to consecutive cells of the battery, and plates a², 62, c², &c. to the same cells,
or simply to the first set of plates respectively, through resistances.
The action of the apparatus is as follows: :-
Suppose, as the cells are charged, the electric pressure in the mains gets too
high. The end Z' of the lever Z Z is lowered, the right hand pawl Y¹ is lifted,
releasing wheel Q. Chain-wheel S (driven by the chain S2) now rotates as shown
by the arrow, carrying with it T, U, R, and P. As the eccentric P rotates, it lifts
the pawl M² and allows the pawl N to be pressed by a spring, shown in dotted lines
in Fig. 2, against ratchet-wheel A, just missing the tooth near which it is shown in
the drawing. When Q has made nearly half a revolution M2 clears ratchet-wheel A,
which, driven by the chain-wheel F, at once flies round until the tooth just released
by M is arrested by pawl N. Q, completing one revolution, again displaces N, at
the same time pushing in M' immediately in front of the next tooth of A. Now A
and the bevel wheel D being fixed on the same sleeve, turn together, therefore
the movement just described has resulted in the rotation of D through one third
of a revolution, and the consequent rotation of B through one sixth of a revolution,
which has brought switch arm d into contact with plate d' (not shown) and
turned arm c clear of its contact-plates; plate c² not being cleared until arm d
had touched plate d'. One cell of the battery has thus been switched out of circuit.
The use of fly X is to retard the rotation of Q after the switch has been thrown
over until the solenoid core has had time to cease oscillating and take up its new
position due to the altered pressure in the mains.
When, in discharging, the pressure falls too low, the other pawl Y¹ is lifted, and,
the other half of the apparatus generally being brought into play, the switch is
rotated in the reverse direction and a cell added to the circuit. The ratchet-wheel A
and its two pawls used for this reversed movement of the switch will face the reverse
way to those shown in Fig. 2.
In the drawings six switching arms are shown; but the number depends upon
the number of teeth in ratchet A; two arms being allowable for each such tooth.
For connecting the switch with the main a disc m is shown, to dip into a trough
of mercury or bear against a brush.
To minimise liability to "hunting," the device shown in Fig. 4 may be used. In
this, Z' is the end of the lever Z Z', the attachment to the solenoid core being
made at n. Two notched wheels P and 9, geared together, and placed in reference
to Z as shown, are driven slowly round by a clock or otherwise in the direction
shown by arrows. When P and 9 are in the position shown, Z' is free to move up
or down, but for the greater part of the time it is locked in the central position by
the two wheels.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. In an automatic switch the use of two independent non-reversible motors, such
as the weighted chains J, for moving the switch both ways.
2. In an automatic switch the use of a balance-gear, such as D, K, D, for enabling
independent forces to move the same switch in opposite directions.
3. In an automatic switch a ratchet-wheel, such as A, and two pawls, such
as M³ and N, for regulating the necessary step-by-step movement of the switch arms,
substantially as described and illustrated in the accompanying drawings.
4. In an automatic switch intermediate ratchet and fly gear, substantially as

page_text: described and illustrated in the accompanying drawings, for reducing the necessary
pull of the solenoid core, (or other pressure meter), and allowing time for oscillations
to subside before the apparatus is again "set," ready for action.
5. In an automatic switch the use of chain-wheels and ratchets for "winding up,"
substantially as described and illustrated in the accompanying drawings.
6. In an automatic switch the use of locking-gear, such as p, q, to reduce
"hunting," substantially as described and illustrated in the accompanying drawings.
7. The general arrangement and combination of parts to form a complete
automatic gear, substantially as described and illustrated in the accompanying
drawings.
Dated this 18th day of October 1890
WILFRID S. BOULT.