Improvements in or relating to Ratchet and Pawl Devices, particu- larly applicable to Clocks and Clockwork Motors.
Year: 1899

page_text: Date of Application, 23rd Jan., 1899-Accepted, 25th Feb., 1899
COMPLETE SPECIFICATION.
Improvements in or relating to Ratchet and Pawl Devices, particu-
larly applicable to Clocks and Clockwork Motors.
I, GEORGE WILLIAM GOEBEL, Merchant, of 8, Market Place, Saalfeld on the Saale,
Germany, 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 improvements in ratchet devices and is particularly
applicable to clocks, watches and clockwork motors.
Since the introduction of spring motors into all kinds of clockwork one of the
most serious drawbacks is that whenever a spring happened to break the consequent
release of the spring case is liable to produce great injury to the cogged wheels,
gearings and spindles of the mechanism.
To meet this drawback the teeth of the cogwheels, instead of terminating in
sharp edges, have been rounded off; but the harm was thereby only lessened, not
avoided.
The object of the present invention is to fully protect the mechanism against
damage consequent on the breaking or snapping off, of the spring, by means of a
ratchet and pawl device fixed on the spring case. For this purpose, two or more
pawls a, b Fig. 1 are arranged so that, for instance, pawl b comes into operation,
whenever pawl a is raised to the extent of half the height of a tooth.
By this means the pitch of the ratchet wheel c is diminished and with it.
the extent of the rebound of the spring-case d, whereby the consequences of the
shock, caused by the rebound or release of the spring case, or driving wheelf to the
clockwise mechanism (cogged wheels, pins and axles) are reduced to a minimum.
In order to produce the alternating action of the pawls a and b, one pawl (b)
is made somewhat longer than the other pawl (a) i.e: the distance from the pivot
of the pawl b to the centre z of the ratchet wheel is greater than that of the pivot y
to the same centre 2 (Fig. 1).
It is of advantage to place the ratchet wheel c as near as possible, in the centre of
the height of the spring case, as shown by the dotted lines in Fig. 2. In watches the
pawls a and b are sunk into the plate, and the ratchet wheel is fixed at the middle
of the spring drum, as shown in Figs. 3 and 4.
In spring motors with a fixed spring drum d, the ratchet wheel c may be fastened
directly on to the driving wheel f. In spring motors for regulators, the pawls must
lie in a vertical plane.
This invention is applicable to all kinds of motors which are driven by spring
power.
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
A
notabat and nawl device. comprising two or more pawls so arranged in

page_text: connection with the ratchet wheel that one of them will engage with a tooth of the
ratchet wheel when the other is at the height of half a tooth; for the purpose of
reducing or preventing the rebound of the spring case or driving wheel consequent
on the breaking of the driving spring substantially as described.
2. The combination and arrangement of parts constituting the complete ratchet
and pawl device for spring motors substantially as described or illustrated in the
accompanying drawings.