US174504A

US174504A - Improvement in knob-latches

Info

Publication number: US174504A
Authority: US
Publication date: 1876-03-07
Anticipated expiration: 1893-03-07

Description

H. H. ELWELL.

KNOB LATCHES.

' Nb.174,504. Pat ente'd March 7,1876;

1714/ rm/ 4? L/ fl/M/ML W fi UNITED. STATES PATENT. QFFEGE,

HENRY H. ELWELL, on NORWALK, comm, ASSIGNOR TO THE NORWALK LOOK, COMPANY, OF SAME 'PLAOE.

|MPROVEMENT* IN KNOB-LATCHES.

Specification forming part of Letters Patent N 0. 174,504, dated March 7, 1876; application filed February 21, 1876, I

To all whom it may concern: Be it known that I, HENRY H. ELWELL, 0 Norwalk, in the county of Fairficld and State of Connecticut, have invented a new [mprovement in Knob-Latches; and I do hereby declare the following, when taken in connection with the accompanying drawings, and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent an interior View of a latch embodyingthisilnprovement.

This invention relates to an improvement in knob-latches, the object being to lock the latch-bolt on one side of the door, so as to prevent its movement through the knob on the other, and to take advantage of the spring which throws the bolt, causing it to serve the double purpose of throwing the bolt and hold ing the lock; and it consists in a cam-lever within the case, so that by turning the said lever it com es'into position against the shoulder in the unlocked position by means of an extension of the spring collar, as more fnlly hereinafter described.

A is the latch-bolt; B, the follower; G, the spring; a, the collar, the spindle passing through the collar a, the said collar serving as a bearin g for the spring in the usual manner. I1 is the locking-lever, arranged upon abearing in the case, and so as to be turned The other end 0 forms a cam for the action of the spring. In the usual construction an independent spring has been applied to hold this locking-lever in either of its two positions.

To dispense with this spring, the collar to is extended to form an arm, d, bearing against the can) 0, and .bent so as to form opposite inclines, one of which will bear upon the under side of the cam in its unlocked position, and the other upon the reverse side in its locked position; hence, in turning the cam, the collar extension Will be thrown back out of its plane, as indicated in broken lines, its fit on the spindle being sufficiently loose -to allow this play. The latch-bolt spring, bearin g upon the front of the collar, tends at all times to force this extension against the cam 0, thus serving a double purpose, and dispensing with the additional spring usually required. ot' the latch-bolt, and its cam held in that or i I claim- In combination with a latch-bolt, its spring and the locking cam-lever c b, the collar a, with its extension at to bear against the cam a, substantially as described.

HENRY H. ELWELL. Witnesses:

WILLIAM T. BONTON, ALBERT F. MINTON.