Improvements in Watchmen's Time-detectors, and Analogous Recording or Checking Apparatus.
Year: 1889

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COMPLETE SPECIFICATION.
[Communicated from abroad by CARL CHRISTOPH THEODOR HAHN, Manufacturer, of
Stuttgart, Germany.]
Improvements in Watchmen's Time-detectors, and Analogous
Recording or Checking Apparatus.
I, MADS PETER HARDT, Electrical Engineer, of 63 Queen Victoria Street, London,
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 watchmen's time detectors, and analogous recording or
checking apparatus, and more particularly to those, in which a circular dial, moved
by clock-work, receives periodical impressions from a set of types operated by keys
which are located at different stations (or by a single stationary key), while the
box containing the clock and dial is carried from place to place by the watchman or
other person, whose movements are to be recorded by the instrument.
The improvements consist, firstly, in the means for producing impressions on the dial;
secondly, in a special device for showing whether the instrument has been opened
since the last examination by the proprietor or controlling officer; thirdly, in a device
that prevents the clock being stopped by a continued pressure of the type on the
travelling dial; and fourthly, in a special construction of recording apparatus or
time detectors, which are examined only at long intervals of time, for instance, once
every week.
r
In the following description, reference will be made to the accompanying drawings,
of which
Fig. 1 is a face view of a watchman's time detector, after it has been opened and
the dial removed.
Fig. 2 is a detached view of the dial.
Fig. 3 is a partial section along line 1-1 of Fig. 1, showing the device for making
a mark in the act of opening the dial.
Fig. 4 is an underside view of the arm that carries the printing type.
Fig. 5 is a face view of a time detector for long periods, such as are used by
herdsmen &c., after the lid has been opened and the dial removed.
Fig. 6 is an end view of the inner clock-frame, showing the type discs or cylinder,
and the means for lifting and supporting the same.
The dial represented by Fig. 2 and belonging to the instrument illustrated by Figs. 1,
3 and 4, is turned by clockwork, as usual, and divided by radial lines representing
the hours from 1 to 12, and by intermediate lines representing minutes or fractions
of hours. The impressions on the dial are made by means of a series of tumblers 1,
2, 3, 4, 5, 6, operated by suitable keys; but instead of using type engraved on the
face of each tumbler, as usual, and thus producing an impression on the underside of
the dial, every time the tumbler is lifted, I make the upper ends of the tumblers
smooth and form the types on the underside of an arm or counter plate A (Fig. 4)
screwed to the inner clock frame and projecting radially over the dial. This counter
plate is omitted in Fig. 1, in order to show the tumblers and the radial slot in the base
plate through which the tumblers project. a, a, a are the holes for the three screws
which secure the counterplate to the clock frame.
The tumblers are lifted without spring action, by turning the key inserted radially
underneath the same, as is the case in some kinds of locks. Every time a tumbler is
lifted, it presses the dial against the corresponding type on the counter plate, thus
producing a distinctive mark on the upper face of the dial.
In order to show, whether the instrument has been opened since the last
examination by the controlling official or the proprietor; I provide the clock frame
with a puncturing lever b, and the lid with a trigger c, which lifts the rear arm of the

page_text: said lever, so as to depress the sharp front end and to perforate the dial, whenever
the lid is opened. d is a perforation in the dial-supporting plate B, into which the
point of the lever benters, after it has perforated the dial. e is a bracket, that holds
the fulcrum of the lever b, and f is a spring, which presses on the rear arm of the
lever, so as to disengage the point from the dial, when the trigger c is no longer in
contact with the said rear arm.
}
In some of the instruments hitherto used, it was possible, to arrest the clock by
keeping the key inserted, and thus gripping the paper between the die and the
counter plate. To prevent this, a spring is inserted between the paper dial and the
clock work. The dial is fixed by two pins g, g, projecting from a plate which is
situated underneath the slotted disc G. The latter is fixed to the spindle, to which
the hour hand would be attached in an ordinary clock. With the same spindle is
connected by means of a spiral spring the said plate that carries the pins 9; 9, pro-
jecting through the slots g¹, g¹. As long as the dial is free to move, the pins g, g will
always remain at one of the semicircular slots, as shown in Fig. 1; but if the dial is
stopped, the pins 9 will remain stationary, while the clock spindle and the disc G
continue to turn. The spiral spring, however, will be coiled up and the pins g
will gradually approach the opposite ends of the slots g' g', until the dial is released,
and the pins g, g allowed to resume their former position in the slots, by uncoiling the
springs.
The detector represented by Figs. 5 and 6 is designed for recording the visits of
a watchman or other employé at one station during a whole week, (7 days)
without the dial having to be removed. This dectector marks on the paper dial (which
revolves once in 24 hours) the initials of the days of the week, on which the key has
been inserted, so that, for example the mark S shows that the watchman has been at
the station on Saturday; and so on.
For this purpose, the marks are made by means of a type-cylinder H (of which
Fig. 6 shows an end view), which is turned on its axle once very day by means
of a ratchet wheel J provided with seven teeth and a disc K which has a single
tooth and makes a complete revolution once per day; for which purpose it is
fixed on the main spindle of the clock-work. The types on the cylinder are
arranged helically, in such a manner, that every motion of the ratchet wheel (that
is one seventh of a revolution) brings a different type to the top of the wheel_H, and
each type marks a different zone of the paper dial that is fixed to the wheel K. The
axle of the type wheel and ratchet wheel is held at both ends in the two sides of
a forked lever or rectangular frame N, which is pivoted at its rear end to the clock
frame, while the front end is situated near the key-hole O, so that the whole lever,
together with the type cylinder, can be lifted by turning the key. Every time
the key is turned, the type-cylinder is jerked up against the paper dial and makes
a mark on its under side. L is the counter plate which is situated vertically over
the axle of, the type-cylinder and serves as an abutment; M is a brake-spring.
As the dial is provided with 24 radial lines corresponding to the 24 hours of
the day, and subdivisions corresponding to fractions of hours, the marked dial
shows exactly at the end of the week, how often and at what minute during the
whole week the watchman has visited the place, where the marking key is attached.
Having now particularly described and ascertained the nature of this said Inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. In a watchman's time detector or analogous recording apparatus of the type
specified, the combination of a series of plain tumblers, with a stationary type-pläte
placed above the dial in line with the said tumblers, and a series of stationary keys
adapted to lift the corresponding tumblers; substantially as described.
2. In a watchman's time detector or analogous recording apparatus of the type
specified, the combination of a perforating lever and spring, with a trigger attached
to the lid and adapted to act on the said lever every time the lid is being opened,
substantially as described.

page_text: 3. In a workman's time detector or analogous recording apparatus of the type
specified, the combination of the clock arbor or central spindle, with a driving plate
carrying the dial plate by means of a pair of pins projecting through the face of the
clock, a spiral spring connecting the driving plate with the clock-arbor, and a sup-
porting disc fixed to the clock-arbor above the said driving plate and provided with a
pair of semicircular slots through which the said pins project; substantially as
described.
"
4. In a time detector for long periods, the combination of a type-cylinder situated
radially underneath the dial plate and carrying type indicating the seven days of the
week, with a ratchet wheel fixed on the axle of the type cylinder, a disc connected
with the going work of the clock and adapted to act on the ratchet wheel once in
24 hours, a frame or lever holding the axle or pivots of the type-cylinder and adapted
to move to and from the dial plate, and a key adapted to press the said frame or lever
towards the dial plate; substantially as described.
Dated this 28th day of September 1889.
M. P. HARDT.
By Fairfax & Wetter,
433, Strand, London, Agents.