A Trip-latch for Lamp Doors.
Year: 1889

page_text: Date of Application 7th Oct., 1889
Complete Specification Left, 3rd July, 1890-Accepted, 30th Aug., 1890
A Trip-latch for Lamp Doors.
I, ARTHUR HAYWOOD CRUMP, of 2 Lee Lane Horwich, Bolton, Lancashire, Gas
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention consists of a Trip-latch or tumbler for the fastening of lamp doors,
or the like, which latch or tumbler turns upon a hinge and is held in either the closed
or the open position by means of a spring, acting upon a two faced heel, formed on
the latch or the carrier thereof, or by means of a balance weight attached to the latch,
or to a lever acting thereon.
The tumbler has two arms, one of which is the latch proper, and confines the lamp
door when closed; and the other is the tripper, against which the lamp door impinges
in the act of closing, thus over-coming the resistance of the spring, and throwing- the
tumbler over from the open to the closed position, in which it is then retained by the
pressure of the spring or weight acting upon the heel aforesaid.
The hinge body or carrier may be in one piece with the framework of the lamp, or
may be rivetted, screwed, soldered, or otherwise fastened thereto.
The spring may as a variation as aforesaid be attached to the tumbler, and the two
faces, upon which it acts, may be formed upon the hinge itself.
From the outer arm, or latch-proper, of the tumbler there stands out a snug
or projection serving to facilitate the opening of the door by means of a lamp-
stick.
The improvements are applicable to various descriptions of lamp-doors, bottoms, or
lids in whatever manner they may be hung.
The door cannot close without bringing the latch into operation, and the door
cannot open without placing the latch in a suitable position to come into operation on
the reclosing of the door. Upon pulling or pushing the tumbler over to the open
position, by means of the snug or projection, the tripper pushes against the inner side
of the door and ensures its opening in the event of its having a tendency to stick. If
a balance-weight be used instead of the spring, such weight is either attached to the
tripper, and is so arranged that its centre of gravity is upon the inside of the pin or
shaft when the tumbler is in the closed position, and upon the outside when'in the
open position; or it is attached to the end of a lever operating upon the heel of the
latch, in lieu of a spring.
Variations in detail, such as the form and material of the latch may be made
without departing from the peculiar character of the invention.
Dated this 25th day of September 1889.
WILLIAM GADD, C.E.,
64, Barton Arcade, Manchester, Agent.
COMPLETE SPECIFICATION.
A Trip-latch for Lamp Doors.
I, ARTHUR HAYWOOD CRUMP, of 2 Lee Lane, Horwich, Bolton, Lancashire, Gas
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 :-
My invention consists of a Trip-latch or tumbler for the fastening of lamp doors, or

page_text: 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:
A trip latch for lamp doors having a flat surface thereon for the action of a spring
or counterbalance weight, and provided with a projection or lever arm, all for the
purpose and in manner substantially as herein shewn and described.
Dated this 2nd day of July 1890.
WILLIAM GADD, C.E.,
64, Barton Arcade, Manchester, Agent.