US2621953A - Latch - Google Patents

Description

Dec. 16, 1952 cHRlSTENSEN 2,621,953

LATCH Filed May 27, 1950 INVENTOR. HANS CHRISTENSEN ATTORNEY Patented Dec. 16, 1952 UNITED STATES PATENT OFFICE LATCH Hans Christensen, Rockaway, Oreg.

Application May 2'7, 1950, Serial No. 164,794

4 Claims.

This invention relates to a latch for doors, windows, screen doors, especially the latter, with especial emphasis on casement or basement windows that swing on hinges.

The objects of the invention are in part as follows:

An improved latch that employs a toggle link with toggle lever, that is especially strong and efficient, comprising the virtues of extreme final pressure in the final closure, characteristic of the toggle joint.

A latch that may be instantly and finely adjusted to compensate for either swelling of wood parts due to storms or, reversely, to compensate for drying out, by a simple movement without tools, available to any one able to use the latch.

Other objects will be apparent from this specification and are pointed out in the claims.

I accomplish these objects by the structure illustrated in the accompanying drawing, in which:

Fig. 1 is a side view of the latch showing its relationship to a door, a fragment of which is shown, with a door casing shown in section to which an operating lever is eye-bolted;

Fig. 2 is of the same structural elements shown in Fig. 1 where the operating lever has locked the door to the casing;

Fig. 3 is a section of Fig. 2 on the plane 3-3, Fig. 2; and

Fig. 4 is a plan view of Fig. 1, with a part of the eyebolt door attaching means omitted.

Describing the structure in greater detail:

A door (or window) structure is indicated by numeral 1 in closed relationship with one member of a casing fragment 2.

Securely attached to the casing 2, is a stud 3, preferably unitary with a plate 3, capable of attachment with a plurality of screws as shown.

The stud 3 is fashioned with a double cammed T head 3" which has a concavely curved cammed surface 33, and for convenience in mounting, a similar surface is shown on the opposite side of the head 3". The stud 3 is the means to which latching means on the closing member such as a door is to be locked.

To complete the lock, an eyebolt 4, preferably threaded at 4', is screwed through a door plate 5, the latter being securely attached to the door by screws or in any preferred manner. A toggle link 6, of clevis U form, is hooked through the eye of the eyebolt 4, as shown, and pivotally engaged with a toggle lever l, the operative parts of which include a handle portion 1' on pivot 'l", and. at least one cam follower 8, but preferably including an additional cam follower 8'. These cam followers are angularly disposed with respect to the toggle lever I and rounded for engagement with the curved rearward surface 33 of the head 3".

The mode of operation is clearly illustrated in the figures, especially Figs. 1 and 2. It is shown that the position of the eyebolt 4, with respect to the threaded shank 4', is a little above the axis of the stud 3. By lowering the eyebolt or raising the stud an equal amount, the mode of operating the latch will be opposite to the one about to be described.

The user will pull the door, window or the like into contact with the casing 2 by the toggle lever itself, assuming that during the pull shut, the parts assume the position shown in Fig. 1. The toggle link 6 is in position to straddle the T head 3" by dropping the cam follower 8 behind the curved cam surface 33, whereupon a downward movement of the lever I will firmly lock the eyebolt 4 to the T head 3" of the stud 3, by means of the intervening connection of the U shaped toggle link 6, with the toggle lever 1, one leg of the toggle link 6 resting on the stud 3, which prevents it from going too far.

With a proper adjustment of the screw thread 4, a very powerful toggle force is applied to the eyebolt 4 by the lever 1. At the scale shown, the force, by the law of the lever, will be something like four and a half times the pressure of the hand on the lever. By turning the threaded portion of the eyebolt 4' to screw the shank of the eyebolt into or out of the door plate 5, the other cam follower 8 may be substituted, to increase or decrease the final force with which the door presses against the casing.

One of the principal advantages of this latch is that its parts move easily into engagement and operation without being watched by the user and, as noted, the latch can work upwards to engage the stud with equal facility, by a slight change in position of either the stud or the eyebolt. Adjustment is also instantaneous if the closure is found too tight or too slack, by a mere right or left hand turn of the eyebolt.

Having fully disclosed my invention so that it can be availed of by the building arts, what I claim as new and desire to secure by Letters Patent, is:

1. A latch for a door or the like swingable in a casing, comprising a door plate, an eyebolt screwed to said door plate, a U shaped arm toggle link swingable by its closed end in the eye of said eyebolt, a toggle lever pivotally mounted within the opposite end of said link, said toggle lever including an angularly formed cam follower, an outstanding T head stud having a shank plate for secure mounting to a casing, said T head being a concavely formed cam, said stud with its T head cam surface being mounted in position for the arms of said U shaped toggle link to straddle said T head and one arm thereof to rest on the stud to provide a fulcrum for said toggle lever.

2. A latch device for a swingable hinged door or the like for mounting in a casing, comprising an eyebolt threadably connectable to a plate on said swingable member, a U shaped link swingable in the eye of said eyebolt, to constitute a toggle link, a T headed stud having a shank portion for mounting substantially normal to the plane of said eyebolt, said stud having a T head adapted to be straddled by the arms of the U shaped toggle link, a toggle lever pivotally mounted between the ends of said U shaped toggle link, said toggle lever formed with a cam follower and said T head formed with a concaved cam surface therefor, the parts being so proportioned that when the U shaped toggle link straddles the T head of said stud one arm contacts the shank of the stud to lock the parts in position.

3. A lever powered latch for closing a door against an abutting casing at right angle contact, comprising an eyebolt screw threaded into a plate on the door, a T headed stud fastened within the casing with a portion thereof in alignment with said eyebolt, a toggle link of U form engaged with the eye of said eyebolt, a toggle lever having a hand portion at one end and a cam at its opposite end pivotally engaged with said toggle link at the end thereof opposite said eyebolt, said toggle link adapted to straddle the T head of the stud and the toggle lever adapted to lock behind said T head with its cam portion, upon suitable movement of said hand portion.

4. A latch for a door or the like, comprising a U like toggle link swingably attachable to a door, a toggle lever embodying an angular cam follower pivotally mounted between the ends of said link, said pivot mounting being at the apex of the angle between said lever and said cam follower, a T stud projecting inwardly from a support, said stud embodying a normally projecting outstanding cam positioned to be straddled by said U like toggle link and engaged by said cam follower.

HANS CHRISTENSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 366,143 Andrews et al. July 5, 1887 960,961 Kusterer June '7, 1910 FOREIGN PATENTS Number Country Date 29,995 Sweden Feb. 1, 1910

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