US2353844A - Keeper - Google Patents

Description

July 18, 1944. 1 J. B. MILNER 2,353,844 v KEEPER y Filed Nov, 21, 1942 2 Sheets-Shea?l 1 I I6 g L ,L 4 ,5, 20

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Patented July 18, 1944 v. Application November 21, 1942, sria1lNm46a4s3 In Great Britain November, `1941., 1

1 Claim.

This invention of improvements in a keeper has for its object the provision of easily appliedl -means for preventing tampering with the shot bolt of a latch lock by the insertion of an instrument through the gap between the striking edge of lthe door and the latch keeper whereby to push back the bolt and thus to unlock the door.

As is understood, hygroscopic swelling or contraction of the wood of a door causes the gap between the free edge of the door and the latch keeper to vary in width and consequently to affect the extent to which the latch bolt enters the keeper.

A keeper, for a springl door-locking latch according to the invention, includes a spring-urged lever located within the keeper for lactuation by the latch bolt, and a spring-urged sliding plate member guided within the keeper for sliding movement in a direction parallel to the direction of movement of the bolt and having a lostmotion operative connection with the lever whereby projection of the bolt into the keeper is accompanied by protrusion of the plate, said lost-motion connection being such that the plate member is not necessarily protruded to an extent proportionate to the displacement of the lever under the action of the bolt.

The sliding plate member may be protruded to the f-ull extent of the movement of the lever. Should, however, the plate member in its advance meet with an obstruction such as, for example, the free edge of the door, further protrusion of the plate member is arrested with the plate member in resilient eng-agement with said edge and the lever is free to continue its movement to the full extent and will thus permit shooting home of the bolt in opposition to the spring acting on the lever,

When the door is open, the plate member is housed entirely within the keeper, and it is only when the door is closed and the bolt shot that the plate member is protruded to protect the latch bolt against tampering. To prevent the striking edge of the plate member from damaging the free edge of the door by causing an indentation, with the risk of the plate member sticking therein, the striking edge of the plate member may be overturned or flanged to present a larger surface to the door and thus to lessen the risk of damage.

A latch keeper according to the invention will now be described with the aid of the accom panying drawings, in which Fig. 1 is a front elevation of the keeper. Fig. 2 is a sectional plan taken through the line II-lI of Fig. l. Fig. 3

is a sectional plan view 'taken throughthe jamb and4 a doorV s howingthe improved keeper in operative position therein. Fig. 4A is a sectional plan similar to Fig. 2 but lshowing a-modied formY of keeper. i l

Referring to Figs. 1 to 3 of the drawings, I0 is the keeper of a rim night latch. The keeper is generally of usual exterior form and is provided in its inner top and bottom walls with slideways II, I2, respectively. -I3 is a metal plate memberaadapted for sliding movement in the slideways and having its front edge bent to form a. 'ange I4. The platev member I3 is formed with slots I3a, I3b. I6 is a two-armed lever fulcrurned on a pin I 1 riveted into the top and bottom walls of the keeper I0.

One arm of the lever I6 is preferably slightly longer than the other. The shorter arm is formed with projections Ila, I6b which project into the slots I3a, I3b of the plate member I3, said projections and Slots constituting a lost-motion operative connection between the lever and the plate member. The longer arm of the lever I6 is normally held with its free end resting against a lip Illa of the keeper by means of a tension spring I9 attached by one end to the keeper and by the other end to the shorter arm of the lever I6. A further tension spring 20 is attached by one end to the plate member I3 and by its other end to a lug Illb on the keeper whereby, as the lever I6 is rocked about the pin I'I by the latch bolt 2I of the rim night latch 22 entering the keeper on being shot, the plate member I3 is protruded under the pull of the spring 2I until the flange I4 meets an obstruction, i. e., the free edge of the door 23, and further movement of the plate member is arrested, see Fig. 3.

If the gap between the free edge of the door :and the striking edge Ic of the keeper be narrow, the movement Vof the plate member is arrested before the latch bolt 2l has entered the keeper to the full extent. The lever I6 is, however, permitted to continue its movement by reason of the slots in the plate member I3, the extent of movement of the lever I6 being limited by a stop I0*.

Fig. 2 shows the plate member I3 in position within the keeper when the mechanism is at rest before the latch bolt has entered the keeper and the plate member does not project from the face of the keeper, and shows how the lever I6 is free to move to allow entry of the latch bolt to the full extent necessary.

The movement of the plate member I3 may be limited by a stop 24 on the plate member meeting a stop 25 on the keeper.

In lieu of the tension springs described, blade springs may be used to operate the plate member and the lever. Fig. 4 shows such a modication in which parts corresponding to those shown in the preceding gures are indicated by the same reference characters but distinguished by the exponent 1.

In Fig. 4, 26 is a blade spring attached at one end to the lever I6' with its free end projecting through the slot in the plate member I3'. 21 is a further blade spring attached at one end to the lever I6 and bearing by its' free end against the inner wall of the keeper I0. Y

When the latch bolt is shot and enters the keeper, the lever I6' is rocked about its pivoty I1-V against the influence of the springv 21, and the spring 28 presses the plate member I3 forwardly to project from the keeper.

When the plate member I3 meets an obstruction, i. e., the free edge of the door, and its movement is arrested, the lever I6 may continue its rocking movement to permit the latch bolt to enter the keeper to the desired extent, the spring 26 being bent or compressed by being pressed against the forward edge of the slot of the now stationary plate member.

When the latch bolt is withdrawn, the leverV I6' is returned to initial position by the spring 21 and moves the plate member I3' back into the keeper Ill.

When the door is open, the plate member I3 is entirely within the keeper, as shown in Fig. 2.

It is only when the latch bolt is "shot that the plate member is protruded from the keeper, see Fig. 3.

The springs I9 and 20 have been shown as single springs but these springs may be duplicated, if desired.

When the keeper is fixed in position, the springs I9 and 20 are concealed and thus kept clean and free from damage.

I claim:

A keeper for a spring door-locking latch, comprising in combination a lever located within said keeper for actuation by a bolt of said latch, a spring within said keeper, said spring urging said lever in the direction to oppose entry of said bolt into said keeper, a plate member guided within said keeper for sliding movement in a direction parallel to that of movement of the bolt, a second spring within said keeper, said second spring urging said plate member in the direction outwardly from said keeper, said plate member having a lost-motion operative connection with said lever, whereby projection of said bolt into said keeper is accompanied by rocking movement of said lever to permit protrusion of said plate member by said second mentioned spring across the gap between said keeper and the adjacent edge of the door into resilient engagement with said edge, said lever being then free for further movement under the action of said bolt and in opposition only to said first spring, whereby to permit shooting home of said bolt.

JAMES BOAM MILNER.

CERMFICATE oF CORRECTION. Patent No. 2,555,8Lm. July 18, 191m.

JAMES BoAM MILNER.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line l, after the word "keeper" insert --or spring door-locking latehes-; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the oase in the Patent Office. l

signed and sealed this 26th ay of september, A. D. 19m.

Leslie Frazer (Seal) Acting Commissioner of Patents.

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