provements in Chronographs.
Year: 1889

page_text: Date of Application, 4th May, 1889
Complete Specification Left, 4th Feb., 1890-Accep'ed, 5th Apr., 1890'
"
PROVISIONAL SPECIFICATION
Improvements in Chronographs.
I HENRY ROBOTтом, of Rose Cottage Over Whitacre, in the County of Warwick,
Watch Maker do hereby declare the nature of my said invention to be as
follows
My invention has for its object improvements in chronographs by which I am
enabled to considerably reduce the amount of skilled labour required in their
manufacture and at the same time lessen the number of parts which has hitherto
been required thereby producing a chronograph much less intricate and at the same
tine more durable and reliable in its action than those previously in use
I also operate the chronograph dial from the ordinary dial of the watch which
renders both dials much more easy to read and this 1 effect without any increased
mechanism being used.
I then
My invention consists of mounting on the arbor of the fourth wheel a roller wheel
having a very fine ratchet tooth formed upon the outside of the face of same
mount upon a bridge a second wheel having teeth upon its face suitable to engage
with the first and this I mount in such a position that it is caused to engage with the
first by a band spring which is fixed to the plate.
This band spring is provided with a swell which is depressed by means of a
pivotted cranked lever, this lever being in turn actuated froin the side of the watch
thereby pressing down the swell of the spring operating the loose ratchet wheel
disengaging the ratchet wheel and stopping the band of the chronograph, at the same
time a second spring is released by the action of the said lever and is thereby allowed
to bear upon the edge of the disengaged ratchet wheel thereby keeping it in the
position where it stopped.
For returning the hand to zero a bolt is provided which by means of an arm on
the lever is made to engage with a pin or catch at the same time as the spring 19
released for starting the ratchet wheels and this bolt is made to engage with the
ordinary cam provided for returning the hand to zero and is released from the
holding pin or catch by a push action & spring.
The action of starting the chronographic hand is as follows -The outside end of
the cranked lever is pressed forward which brings the other and cranked end of the
lever away from depressing upon the spring thereby allowing the spring to press the
two ratchet faces of the wheels together thereby giving motion to the hand.
By this movement the cranked end of the lever also forces
away the spring
presses against the side of the loose ratchet wheel and at the same time causes the
bolt which engages with the cam to be hooked back upon a pin
which
The action of stopping being as follows:-The end of the cranked lever outside
the watch or chronograph is pulled backwards which causes the cranked end of the
pivoted lever to press down the spring, and allow the wheels to become disengaged at
the same time releasing the spring which then bears against the side of the loose
ratchet, and keeps it in the position in which it stopped.
The action of returning the hand to zero is as follows -By the push arrangement
which may be placed either at the side or at the pendant the pin or catch is caused to
disengage from the bolt which then shoots forward by means of a spring and
engages with the cam at the point when the hand is at zero, the pressure on the bolt
being preferably at right angles.
1 do not confine myself to the particular details which may be considerably altered
without departing from the nature of my invention and I may place them either in
front or at the back of the ordinary watch mechanism but I prefer to place them at

page_text: the back and have a separate dial for the chronographic hand at the bick of the watch
thereby preventing any confusion when refering to either one or the other of the
dials.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for Applicant.
COMPLETE SPECIFICATION.
Improvements in Chronographs.
I, HENRY ROBOTTOM of Rose Cottage Over Whitacre, in the County of Warwick,
Watch Maker do hereby declare the nature of my said invention and in what
manner the same is to be performed to be particularly described & ascertained in
& by the following statement
My invention has for its object improvements in chronographs by which I am
enabled to considerably reduce the amount of skilled labour required in their manu-
facture & at the same time lessen the number of parts which has hitherto been
required thereby producing a chronograph much less intricate & at the same time
more durable and reliable in its action than those previously in use
I also operate the chronograph dial from the ordinary dial of the watch which
renders both dials much more easy to read & this I effect without any increased
mechanism being used.
My invention consists of mounting on the arbor of the fourth wheel a roller
wheel which having a very fine ratchet tooth formed upon the outside of the face of
same. I then mount upon a bridge a second wheel having teeth upon its face suitable
to engage with the first and this I mount in such a position that it is caused to
engage with the first by a band spring which is fixed to the plate.
This band spring is provided with a swell which is depressed by means of a pivotted
cranked lever, this lever being in turn actuated from the side of the watch thereby
pressing down the swell of the spring operating the loose ratchet wheel disengaging
the ratchet wheel, and stopping the hand of the chronograph, at the same time a
second spring is released by the action of the said lever & is thereby allowed to hear
upon the edge of the disengaged ratchet wheel thereby keeping it in the position
where it stopped.
For returning the hand to zero a bolt is provided which by means of an arm on
the lever is made to engage with a pin or catch at the same time as the spring is
released for starting the ratchet wheels & this bolt is made to engage with the
ordinary cam provided for returning the hand to zero & is released from the holding
pin or catch by a push action and spring
The action of starting the chronograph is as follows:-The outside end of the
cranked lever is pressed forward which brings the other and cranked end of the
lever away from depressing upon the spring thereby allowing the spring to press
the two ratchet faces of the wheels together thereby giving motion to the hand.
By this movement the cranked end of the lever also forces away the spring which
presses against the side of the loose ratchet wheel & at the same time causes the bolt
which engages with the cam to be hooked back upon a pin.
The action of stopping being as follows -The end of the cranked lever outside
the watch or chronograph is pulled backwards which causes the cranked end of the
pivotted lever to press down the sping & allow the wheels to become disengaged at
the same time releasing the spring which then bears side of the loose ratchet & keeps
it in the position in which it stopped
The action of returning the hand to zero is as follows .-By the push arrangement
which may be placed either at the side or at the pendent the pin or catch is caused
to disengage from the bolt which then shoots forward by means of a spring &
engages with the cam at the point when the hand is at zero the pressure on the bolt
being preferably at right angles,

page_text: I do not confine myself to the particular details which may be considerably altered
without departing from the nature of my invention & I may place them either in
front or at the back of the ordinary watch mechanism but I prefer to place them at
the back & have a separate dial for the chronograph hand at the back of the watch
thereby preventing any confusion when referring to either one or other of the
dials.
In order that my invention may be clearly understood & more easily carried into
practice I have appended hereunto a double sized sheet of drawings upon which I
have illustrated several modifications of the mode of carrying out my invention &
which will enable any practical person to apply my improvements to all classes of
watches.
Figure 1 is an elevation of the one side of the plate A shewing one arrangement
of my improved mechanism attached thereto.
Figure 2 is an elevation of the other side of the plate A shewing the other part of
the same arrangement as Figure 1.
Figure 3 is a section through Figures 1 and 2 on the line 1-2 shewing the tipsy
key ratchets B & B₁ disengaged.
Figure 4 is a similar section to Figure 3 but shewing the tipsy key ratchets engaging
with each other.
Figure 4 is a section through a portion of the plate A for shewing the action of the
lever upon the pin b
Figure 5 is an elevation of one side of the plate A shewing a modification in the
arrangement of the various parts.
Figure 6 is an elevation of the other side of the plate A in connection with this
arrangement.
Figure 7 is an elevation of one side of the plate A of an ordinary watch movement
which is inverted and shews the lower tipsy keş ratchet B for which purpose the top
tipsy key ratchet B¹ is removed.
Figure 8 is a similar elevation of the same side of the plate in this case shewing
the top tipsy key ratchet, B' and cain D in position as also the connection with the third
wheel E.
In carrying out my invention I mount the lower tipsy key ratchet B upon the
arbory of the fourth wheel F so that the toothed face of the said ratchet B will
engage with the similar face of a second tipsy key ratchet B' which is mounted by
means of the hand arbour f' in the bridge 63 in such a position that the ratchet
wheel B is made to engage with the ratchet wheel B¹ by means of the spring b³ which
is fixed to the bridge & engages with and raises and depresses the fourth wheel
arbor upon which the ratchet wheel B and fourth wheel F are fixed. The pin b
is provided in the plate so as to press against the underside of the spring when the
pin is depressed by the lever 6 pivotted at Ke which is in turn actuated by the arm h¹
on the lever H and thus by the depression or release of the pin 6 the ratchets B & B¹
are made to engage or not by means of the catch ' & the chronograph hand which is
mounted on the arbor f¹ is operated or not as the case may be. By the movement
of the lever H for disengaging the ratchets the spring K is also released as shown at
Figure 1 and is thus allowed to bear against the edge of the ratchet B¹ & retain it &
thereby the chronograph hand is retained in the position which it occupied at the
moment of disengagement & where it remains until the pin L is depressed in the
direction of the arrow sufficiently to cause the pivotted crank m' to release the head n'
of the bolt N which it bad previously retained which bolt N then flies forward by
means of the presence of the spring n³ & presses round the heart shaped cam D until
it arrives at the position shewn in Figure 1 which is with the hand at zero. It will
be seen that the action of the lever H when operated to start the hand also by means
of the end withdraws the bolt N until the head n¹ of the bolt engages with the
catch m* upon the pivoted crank m'. In Figures 5 & 6 a more simple method of
operating the bolt N is shown the release in this case being effected from the pendent
while the method of engaging & disengaging the ratchets would be substantially the
same as described to the last.

page_text: In the case of an ordinary watch movement the arbor of the ratchet B¹ carrying
the cam
D would pass through the hollow arbor P of the centre wheel
pinion P¹ the other ratchet B being mounted below and is provided with the pinion 68
which is attached to it & which engages with the toothed wheel E which is in turn
attached to the arbor e¹ of the third wheel E the bolt & ratchets being operated &
governed in a similar manner to those before described.
The action of starting the chronograph hand is as follows:-The catch h³ is pressed
forward in the direction of the arrow X which by means of the lever 65 releases the
pressure of the pin 64 upon the spring 63 & allows the said spring 63 to press the
ratchets together & thereby start the hand while by the same movement of the catch'h'
the spring K is removed from pressing against the side of the ratchet B¹ & the bolt N
is at the same time withdrawn by the en³ of the lever H until it is hooked back
by the catch m².
The action of stopping the hand is as follows -The catch h² being then forward is
pressed backwards in the direction of the arrow Y which causes the lever b' to operate the
pin 64 against the spring thereby withdrawing the ratchet B from engagement
with B while at the same time the spring K is released & allowed to press against
the edge of the ratchet E' thereby retaining it in the exact position in which it
stopped.
The action of returning the hand to zero is as follows:-By the push arrangement L
the pin or catch m² is caused to disengage from the head of the bolt N which is made
'to shoot forward by means of the spring n & turn the cam D until it occupies the
position shewn in fig. 1 at which point the hand is at zero.
I may modify the particular details without departing from the nature of my said
invention.
Having now particularly described & ascertained the nature of my said inven-
tion & in what manner the same is to be performed I declare that what I
claim 18:
In improvements in Chronographs the particular arrangement of parts for starting,
stopping & returning the hand to zero substantially as berein set forth & shewn upon
the accompanying drawings.
Dated this 3rd day of February 1800.
GEORGE BARKER,
77, Colmore Row, Birmingham, Agent for Applicant.