An Improved Signal Bell.
Year: 1889

page_text: COMPLETE SPECIFICATION.
An Improved Signal Bell.
1 ENGELBRECHT OLSEN of Walkerville in the county of Silver Bow and Territory
of Montana in the United States of America Mechanical 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 :-
The object of this my invention is to provide a signal bell applicable for all purposes
but which will be more especially suitable for use in mines in which bell the apparatus
for striking the same is of an extremely simple construction is very easy of adjust-
ment and is certain of action.
In order the more clearly to explain this my invention and in what manner the
same is to be performed I refer to the accompanying drawing wherein I have shewn
a plan view of my improved signal bell.
On a post erected on a base plate A I secure in any convenient or usual manner a
bell B and in a suitable position near this bell B a striking lever C is pivoted on the
base plate A at the point D and on the free end of this lever C, is an hammer
head E which head E can work in a plane coincident with the bell B and the move-
ment of the lever is controlled and governed by a stop F and a spring G both of
which are mounted on or secured to the base plate A. In the lever C and near its
pivoted end is formed a slot H where through a trip lever J can so pass that the
hooked head of this lever J engages the edge of the slot H heing held and maintained
in such engagement by a spring K mounted on or secured to the base plate A and
this trip lever J is jointed to an operating lever L pivoted on the base plate A at the
point M and the free end of this lever L works in a keeper N secured to the base
plate A. To the free end of the operating lever L is connected a tension rod P the
other end whereof is connected to a tension spring R mounted on or secured to the
base plate A and this rod P is preferably so connected to the lever L and the tension
spring R as to be adjustable which can conveniently be effected as is shewn in the
drawing by forming a series of perforations or holes S in the free end of the lever L
and a corresponding series of perforations or holes in the free end of the tension
spring R to one pair of which the rod P can be connected the exact tension of the
spring R on the lever L being regulated by a screw nut on the rod P. The afore-
said series of perforations or holes S is continued along the lever L as nearly to the
pivot thereof as may be desirable to one of which perforations or holes S the pull
cord V is connected whereby the weight of this pull cord V will be neutralized for as
this weight increases so the pull cord V will be connected to one of the perforations
or holes S nearer to the pivot of the lever L. Thus and by these arrangements the
certainty of the action of this apparatus for striking the bell and the ease of the
adjustment thereof is ensured.
When the pull cord for any reason cannot be led directly from this bell to the
place of operation one or more bell crank or other levers T can be interposed as may
be necessary and in one or both of the arms of each lever T 1 should preferably
make a corresponding series of perforations or holes for the same purpose.

page_text: The action of this apparatus in striking the bell is as follows.
When the pull cord V is operated it draws the operating lever Las also the lever
or levers T if any into the positions shewn by dotted lines which lever L through the
hooked trip lever J draws the striking lever C into the position also shewn by dotted
lines in which position the hook of the trip lever J disengages itself of the edge of
the slot H thus releasing the lever C and allowing the spring G to throw the same
forward until the head E thereof strikes the bell B and then the pull cord V can be
released and the spring R through the rod P draws the lever Las also the lever or
levers T if any back into their former positions and the hooked trip lever J moving
through the slot H in the lever is caused again to engage the edge of this slot H
by the spring K and the apparatus is again in readiness to strike the bell when
desired.
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 a signal bell the combination with a spring-actuated striking lever of an
operating lever having a series of perforations or holes for the connection of the pull
cord a tension spring a rod connecting the tension spring and the operating lever and
a spring-actuated trip lever jointed to the operating lever and engaging the striking
lever substantially as hereinbefore described.
2. The combination with a bell B mounted on a base plate A a striking lever C
having a slot H and an head E and a trip lever J having an hooked head to engage
the edge of the slot H of a spring G a spring K an operating lever L a rod P and a
tension spring R substantially as hereinbefore described.
3. The combination with a base plate A a bell B and a striking lever C actuated
by a spring G of a trip lever J actuated by a spring K an operating lever L provided
with perforations or holes and adjustable tension rod P and a spring R also provided
with perforations or holes substantially as hereinbefore described.
Dated this 10th day of July 1889
HART & Co.,
186, Fleet Street, London, E.C., Agents for the Applicant.