Improvements in Latches.
Year: 1890

page_text: Date of Application, 7th Nov., 1890
Complete Specification Left, 7th Aug., 1891-Accepted. 12th Sent
1801
PROVISIONAL SPECIFICATION.
Improvements in Latches.
I WILLIAM KNEEN of the firm of Ashworth and Kneen of 1494 Aldersgate
Street in the City of London Manufacturers do hereby declare the nature of this
invention to be as follows :-
My invention has for its object to provide an efficient and simple latch which will
operate with certainty without the use of springs.
According to my invention the latch bolt may be either one arranged to run
down an incline after the manner of what is now known as Ashworth and Kneen's
toboggan latch or it may be on one arm of a bell-crank lever centered to a pin fixed
in the latch case.
The spindle of the operating handle is passed through a square
holed boss in the latch case which square holed boss carries a single or double
armed lever which acts upon the shorter arm of a bell crank lever centered to a pin
fixed in the latch case the other arm of which lever is of considerable length and
weight and extends along the latch case which is made long for the purpose of
accommodating it. The extreme end of this long arm of the said lever carries a
pin which engages in a slot in the arm of the bell crank lever carrying the latch
bolt or in a slot in the latch bolt itself if it be one of the toboggan kind.
The length and weight of the operating bell-crank lever ensures the proper
return of the latch to its shot position without liability to its becoming jammed.
Dated this 7th day of November 1890.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, Agents.
COMPLETE SPECIFICATION.
Improvements in Latches.
I, WILLIAM KNEEN of the firm of Ashworth and Kneen of 1494 Aldersgate
Street in the City of London, Manufacturers, 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 :-
My invention has for its object to provide an efficient and simple latch which will
operate with certainty without the use of springs.
According to my invention the latch bolt may be either one arranged to run
down an incline after the manner of what is now known as Ashworth and Kneen's
toboggan latch or it may be on one arm of a bell-crank lever centered to a piu fixed
in the latch case. The spindle of the operating handle is passed through a square
holed boss in the latch case which square holed boss carries a single or double
armed lever which acts upon the shorter arm (or shorter arms) of a lever centered
to a pin fixed in the latch case the other arm of which lever is of considerable
length and weight and extends along the latch case which is made if necessary of
extra length for the purpose of accommodating it. The extreme end of this long
arm of the said lever carries a pin which engages in a slot on the arm of the bell-
crank lever carrying the latch bolt or in a slot in the latch bolt itself if it be one of
the toboggan kind.
The length and weight of the operating lever ensures the proper return of the
atch to its shot position without liability to its becoming jammed.
Figure 1 of the accompanying drawing represents a latch arranged according to
ny invention and Figure 2 is a modification.
In these figures have shewn the latch bolt as being on one arm of a bell-
[Price 61

page_text: crank lever centered to the latch case but it will be understood that it may
desired be one which runs down an incline as before stated.
if
Referring to Figure 1. A is the latch case is the spindle to which the operating
handles are fixed. The said spindle passes through a correspondingly formed hole
in the boss B2 which has formed on or fixed to it a lever B with two arms 263
bearing respectively on opposite sides of the arms ec³ of the double bell crank
lever centered at c to the latch case the long arm C of which lever is of considerable
length and weight and extends along the latch case as shown. The outer end of
the arm C carries a pin c which engages in the slot d in the arm of the latch
bolt lever D centered to the latch case at d³.
In this arrangement it will be seen that the latch bolt D is withdrawn in
whichever direction the handles are turned.
Figure 2 shews a modification wherein the latch is withdrawn when the handles
are turned in one direction only. The lever B bears at its end 2 on the short
arne² of the lever C. The parts are marked with the same letters of reference as
those employed to denote the corresponding parts in Figure 1.
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,
1st. A latch having a lever carried by the operating spindle and acting on the
short arm or arms of a latch operating lever having its opposite arm made as and
for the purpose hereinbefore described.
2nd. A latch constructed as herein before described and shewn in Figure 1 of
the accompanying drawing.
3rd. A latch constructed as herein before described and shewn in Figure 2 of the
accompanying drawing.
Dated this 7th day of August 1891.
J. H. JOHNSON & Co.,
Agents.