Improvements in or relating to Hammers or Tappers Actuated Electrically.
Year: 1898

page_text: Date of Application, 26th Aug., 1898
Complete Specification Left, 24th May, 1899-Accepted, 15th July, 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to Hammers or Tappers Actuated
Electrically.
CHARLES TURNBULL, Junior, Electrician, Hylton Lodge, North Shields, do hereby
declare the nature of this invention to be as follows:-
Machines made under my invention consist of an electromagnet combined with
an armature, one of which can move relatively to the other. In my description
In connection with the moving part
I shall suppose that the armature moves.
will be a hammer or tapper which may be used to strike a bell or be used as a
dentists hammer or be used to deliver blows under any suitable circumstances.
My invention has for its object the governing of the making & breaking of the
magnet current so that the magnet may act on the armature in an efficient
manner. It consists mainly of a switch in connection with the mechanism &
actuated by any of its parts which switch is to work in such a way that the contact
is made when the armature is away from the magnet & not broken until the
armature in the course of its travel under the action of the magnet has come to
a stop by hitting against the magnet or some device to limit its travel. The
operation of the switch is as follows. When the armature is away from the
magnet the parts of the switch come or are caused to come into contact so making
the current. The parts of the switch may be parts of the armature or of attach-
ments thereto or they may be part or parts of the hammer or hammer bar or of
Which ever parts
attachments thereto or of any suitable part of the mechanism.
of the mechanism are chosen will be suitably insulated from each other. The
operation is as follows. When the armature is away from the magnet these
two parts come together under the action of springs or gravity or any suitable
means & so make the contact which may be assisted by supplementary contacts.
While the armature is moving under the action of the magnet the contact is
maintained. When the armature is stopped from moving the contact is broken
by the momentum of the part or parts or by the springing of some suitable part.
Thereupon the armature moves into its original position & waits until the hammer
having completed its work the parts of the switch are again caused to come
together when the operation is repeated. The hammer can be part of the
armature or be driven from it by suitable levers or other means & these means
can be used in connection with the making & breaking arrangement in the
manner as above set out. If the switch be a separate piece of mechanism it may
be driven by some of the moving parts of the other mechanism but its action in
making & breaking the current will be similar to that set forth.
Dated this Twenty-sixth day of August 1898.

page_text: Improvements in or relating to Hammers or Tappers Actuated
Electrically.
CHARLES TURNBULL, Jnr., Hylton Lodge, North Shields, Electrician, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
-
66
The object of my invention is to provide a means for making & breaking an
electric current in such a way that a relative motion may be produced between
a magnet & armature in an efficient manner. So that in fact the current be not
made until the magnet & armature are away from each other, & that the current
be not broken until the magnet & armature are close together. The equivalent
of a magnet & armature such as a solenoid & core can be used. For the purpose
of making the description clear, and as the intention is to utilise the above motion
for producing a hammering or tapping action, I will take the special case of the
motion being used to actuate a hammer which beats a bell or gong, the com-
bination forming an improved electric bell. The magnet "M M is shown fixed
to a base board while the armature A" is pivoted at "P" so that it can swing
to and fro as regards the magnet. Attached to the armature is the armature
bar "AB" insulated electrically from it. The hammer "H" is attached to
the armature by means of a spring or springy connection "S." The electric
circuit is as follows. The current comes from its source to the terminal "T,”
thence by a suitable connection to the armature & through the spring "S" to
the contact "C₁" & thence to "C." For as is shown in the figure when the
armature is away from the magnet under the action of gravity or springs or a
spring or some equivalent the hammer "H" & the spring "S" are arranged &
proportioned so that "C₁ & "C" come into contact the motion of the armature
backwards being limited by the adjusting screw "AS" or some suitable means.
From "C" the current flows as shown by the dotted line through a flexible con-
nection to the magnet windings thence to terminal "T" & thence to the current
source. The effect of the current flowing is to energise the magnet which there-
upon draws the armature to it until it is arrested in its motion by striking against
the magnet or some stop the contact being maintained meanwhile. On the
armature being arrested the hammer continues to move under the action of
momentum thus causing the spring "S" to bend. The effect of this seeing that
the bar "AB" does not bend is that the contact "C₁" leaves "C" breaking the
current. After the hammer has struck the object-in the case shown it is a
gong on the inside, the gong in the sketch being shown broken
to show the hammer--it rebounds and as the current is now broken and the
away
magnet consequently demagnetised the armature falls away from the magnet
under the action of gravity or is drawn away by spring action or some suitable
means until arrested by the stop or by some suitable means when the con-
facts "C" & "C₂" again come together so that the current again flows & the
operation is repeated. The apparatus can evidently be arranged so that any form
of magnet & armature may be used without altering the principle by which the
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current is made & broken.
Having now particularly described & ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. For a means of making & breaking an electric circuit & current so as to

page_text: control the mutual action of a magnet & armature by a switch operated by & act-
ing under the momentum of the part or parts of the mechanism as above described
as applied to a hammer of an electric bell.
2. For a means of making & breaking an electric circuit and current so as to
control the mutual action of a magnet & armature by a switch operated by and
acting under the momentum of the part or parts of the mechanism as above
described as applied to a hammer or tapper for dental or other purposes.
Dated this 23rd day of May 1899
CHARLES TURNBULL, JNR.,
Hylton Lodge, North Shields.