US 3861727 A
An electric release strike in which a strike bolt is supported for swinging movement to a position projecting through a casing opening and to a retracted position, the bolt being spring urged to its projecting position. A latch in the casing includes a frame pivoted for swinging movement to latching and non-latching positions, and in the latching position is pivoted over-center to occupy a position in the path of movement of the strike bolt towards its retracted position. The latch frame is spring urged to a latching position by a coupled actuator in the form of a solenoid plunger operatively associated with an energizable solenoid coil positioned exteriorly and projecting rearwardly of the casing, the coil assembly being removably mountable from the exterior of the casing to permit ease of replacement or change to a coil having a different characteristic. The solenoid has a pin and slot connection with the latch frame which provides a dead-lock in the latching position of the latch frame.
Claims available in
Description (OCR text may contain errors)
United States Patent Froerup et al.
[ Jan. 21, 1975 1 ELECTRICALLY RELEASED STRIKE  Inventors: Carl Froerup, Glendale; Russell L.
Mitchell, Burbank, both of Calif.-
 Assignee: Adams Rite Manufacturing Company, Glendale, Calif.
 Filed: Mar. 12,1973
 Appl. No.1 340,235
Primary ExaminerRichard E. Moore Attorney, Agent, or Firm-Whann & McMonigal [5 7] ABSTRACT An electric release strike in which a strike bolt is supported for swinging movement to a position projecting through a casing opening and to a retracted position, the bolt being spring urged to its projecting position. A latch in the casing includes a frame pivoted for swinging movement to latching and non-latching positions, and in the latching position is pivoted overcenter to occupy a position in the path of movement of the strike bolt towards its retracted position. The latch frame is spring urged to a latching position by a coupled actuator in the form of a solenoid plunger operatively associated with an energizable solenoid coil positioned exteriorly and projecting rearwardly of the casing, the coil assembly being removably mountable from the exterior of the casing to permit ease of replacement or change to a coil having a different characteristic. The solenoid has a pin and slot connection with the latch frame which provides a dead-lock in the latching position of the latch frame.
9 Claims, 5 Drawing Figures ELECTRICALLY RELEASED STRIKE BACKGROUND OF THE INVENTION The invention relates generally to the field of latches and constitutes an improvement in the electric release strike as disclosed in US. Pat. No. 3,638,984.
Conventional devices heretofore available for the purpose described herein embody inherent undesirable features which not only present potential sources of trouble, but also make them more difficult to install and maintain in good operating condition.
For example, in one known conventional embodiment, the casing structure and strike plate are permanently connected, and the strike plate also functions as a face plate. In such a construction, the face plate portion cannot be varied to meet different installation requirements, nor to provide a different aesthetic decorative effect.
In different localities, it is desirable to change the electric actuating coil of the device, for example, to operate under different voltages, or to replace a coil which has failed. In the conventional device noted above, the coil is mounted within the housing or casing of the device, which renders its accessibility difficult.
The actuating coil in this conventional device is associated with a relatively complicated latching mechanism that utilizes a multiplicity of parts which do not cooperate to latch the strike bolt in a positive manner. Also, the device has a release mechanism which includes a pivoted armature arrangement that coacts with other linkages to effect the latching operation, this armature being normally urged to a latching position by means of a leaf spring which presents a potential source of trouble, for example, failure due to metal fatigue when operated over a long period of time. Also, the manner in which this spring is mounted enables it to shift its position so as to produce malfunctions and prevent the desired proper operation of the device.
While the structure of the noted patent overcame and for the most part eliminated the above, as well as other inherent undesirable drawbacks in the construction of the conventionally available devices, it has now become apparent that the strike arrangement of the patent could be desirably improved by providing a latch structure which would be dead-locked in the latching position. The present invention is therefore concerned with and discloses the improved dead-locking feature.
SUMMARY OF THE INVENTION The present invention relates generally to latching devices, and is more particularly concerned with improvements in devices conventionally known as an electric release strike."
One object of the herein described invention is to provide a remotely releasable strike, which is of simple construction, embodies relatively few operative parts, and which will operate with a positive latching and releasing action of the strike bolt, and in the latching position will operate to dead-lock the latch against movement.
A further object is to provide in an electric release strike, an improved actuator means in the form of a solenoid coil and solenoid which is connected with the latching'mechanism through a pin and slot connection so arranged as to provide a dead-lock for the latch, when it is in latching position, but which will be relased when the solenoid coil is energized to actuate the latch to a non-latching position.
Further objects of the invention will be brought out in the following part of the specification, wherein detailed description is for the purpose of fully disclosing the invention without placing limitations thereon.
BRIEF DESCRIPTION OF THE DRAWINGS Referring to the accompanying drawings, which are for illustrative purposes only:
FIG. 1 is an elevational view of an electric release strike according to the present invention, looking towards the face plate thereof;
FIG. 2 is a side view, partly in section and having cutaway portions to disclose the cooperative relationship of the various components, the latch being in latching position;
FIG. 3 is a fragmentary view, similar to FIG. 2, but showing the latch in a non-latching position;
FIG. 4 is a transverse section through the same, taken substantially on line 44 of FIG. 2; and
FIG. 5 is a transverse section through the same taken substantially on line 5-5 of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more specifically to the drawings, for illustrative purposes, the present invention is shown as being embodied in an electric release strike unit as generally indicated by the numeral 10, wherein the essential components are mounted within a casing structure 11 and include a pivotally mounted strike bolt 12 which is normally urged into a position projecting through a casing opening and registered openings 13 in a strike plate 14 and overlying attached face plate 15.
As best shown in FIGS. 2 and 4, the casing structure 11 is fabricated from a suitable metal or other material of generally uniform thickness to provide a box-like structure having spaced side walls 16 and 17, the latter being of less depth than the former, which are rearwardly bridged by a back wall 18. The top of the casing is formed by a top wall 19 which extends forwardly and at the front of the casing is deflected to provide a rightangled projecting arm 20. The bottom of the casing is formed by a bottom wall 21 which is likewise provided at its forward end with a right-angled projecting arm 22, this arm being of greater length than the arm 20. As thus arranged, the casing is open on its front side, and the arms 20 and 22 provide mounting lugs for the attachment of the strike plate 14 by means of appropriate mounting screws 23-23 which are adapted to threadably engage in tapped openings 24-24 respectively in the projecting arms 20 and 22.
As best shown in FIG. I, the strike plate has at one side of its bolt opening, a recessed integrally formed side portion 24' which is defined by a depressed bottom wall 25, raised end walls 26 and 27, and an inner back wall 28 of conventional arrangement, the end walls 26 and 27 and back wall 28 projecting slightly above the plane of the Strike plate proper.
The face plate 15 is attached to the strike plate by retaining screws 2929, and along one side is shaped to conform to the configuration of the strike plate along the end walls 26 and 27, and wall 28. The provision of a separate face plate is an important feature in that it provides a positive retainer for the underlying screws 23 and permits the use of face plates of varied finish,
length and general configuration in order to obtain different desirable aesthetic appearances as between different installations. This is not possible with the conventional integrally formed strike plate and face plate.
The strike bolt 12 is transversely of a hook-shape with a pivotally mounted leg portion 12a and an outer hook portion 12b as best indicated in FIG. 4. The strike bolt is mounted in the open side of the casing structure upon a pivot pin 30 having its lowermost end supported in the bottom wall 21, while the upper end of the pin is supported in an arm 31 of a bracket piece 32 secured as by welding or otherwise to the outer surface of the casing side wall 16, the arm 31 projecting through an edge slot 33 provided in the side wall 16. The strike bolt is normally urged towards a position projecting through the registered openings 13 by means of a coiled spring 34, one end of this spring bearing against the side wall 16, and the other end bearing against the strike bolt. As thus arranged, the strike bolt is movable towards a retracted released position against the force of this spring. In its projecting position, the strike bolt has an outer surface of its hook portion 12b extending adjacently along an edge 35 of the registered strike plate and face plate openings 13. The strike bolt is provided with a lateral edge projection 36 which is arranged to occupy an overlapping position with respect to the edge 35, and thus close the space between this edge and the adjacent face of the strike bolt so as to provide against the insertion of a tool for unauthorized movement of the strike bolt to a released position. The edge projection thus provides an anti-pick flange as a safety feature of construction.
Latching means, as generally indicated by the numeral 37, are provided rearwardly of the strike bolt within the casing for normally opposing movement of the strike bolt to a retracted position, but being electrically movable to a non-latching position in order to permit retracted movement of the strike bolt by moving the associated latched door in a door opening direction.
More specifically, as shown in FIG. 2 and FIG. 4, the latching means comprises a generally U-shaped latch frame 38 which is formed from a flat plate metallic material to provide a bridging wall 39 which extends between integrally formed side walls 40 and 41. The latch frame is pivoted adjacent the back wall 18 of the casing upon a pivot pin 42 which extends through appropriate openings in the side walls 40 and 41 and has its opposite ends respectively supported in the casing side walls 16 and 17 to permit vertical swinging movement of the latch frame, as seen in FIG. 2, into latching and nonlatching positions with respect to the path of movement of the strike bolt 12. Downward swinging movement of the latch frame to its latching position is limited and determined by a stop 43 which constitutes an integrally formed arm of the bracket piece 32, the arm 43 projecting through an opening 44 in the side wall 16 of the casing. The side walls 40 and 41 at the ends opposite their pivoted ends carries an antifriction roller 45 which is mounted upon a supporting pin or shaft 46 having its respective ends supported in the side walls 40 and 41 of the latch frame. It will be observed that the axis of the shaft 46, in the latching position of the latch frame, occupies an over-center position with respect to the axis of the pivot pin 42 of the latch. Thus, any pressure exerted upon the strike bolt tending to force it towards its retracted position will cause the strike bolt to engage the roller and cause clockwise movement of the latch frame so as to more forcibly engage the stop 43 and prevent opening of the door until the latch member is electrically released by means which will hereinafter be described in detail. The provision of the antifriction roller 45 permits movement of the latch member more easily to its non-latching position.
Above the roller 45, the side walls 40 and 41 of the latch frame are provided with transversely aligned similar L-shaped slots 4747, each having leg portions 47a and 47b in substantially right angled relation. As shown in FIG. 2, it will be observed that in the latching position of the latch frame the leg portion 47a occupies a substantially vertical position while the leg portion 47b extends substantially horizontally.
An actuator plunger 49 extends horizontally above the latch frame and has an end connected with the latch frame by means of a connecting pin 50 having its respective ends positioned in the slots 4747 of the side walls 40 and 41 of the latch frame. The actuator thus comprises a solenoid plunger which is operatively associated with and forms a component of a solenoid assembly 51 having an energizable solenoid coil 52, and projecting rearwardly from the back wall 18 of the casing structure.
The coil 52 is mounted within a coil housing 53 which is provided at one end with a tubular neck portion 54 adapted to be inserted from the exterior of the casing structure 11 through an opening 55 in the back wall 18 of the casing structure. The coil housing is retained in mounted position by means of a hair-pin type retaining clip 56 adapted to be inserted around the neck portion 54 within the casing 11 between the inner surface of the back wall 18 and a circumferential flange 57 formed on the neck portion. The neck portion is tubular and receives one end of the actuator solenoid 49 endwise therethrough. A coiled compression spring 58 is positioned around the adjacent end portion of the solenoid with one end bearing against the flange 57, and its other end bearing against an abutment washer 59 carried by the connected end of the actuator 49. The spring 58 normally urges the actuator toward the right and acts to resiliently retain the latch frame in its latching position, as shown in FIG. 2. Energization of the solenoid coil 52 operates to swing the latch member in a counter-clockwise direction to a non-latching position. It will be noted, of course, that in this position, the latch member is translated so that the roller 45 will be moved out of the path of swinging movement of the strike bolt 12, thus permitting it to be moved to a retracted position during energization of the solenoid coil.
Mounting of the solenoid coil and its housing 53 from the exterior of the casing 11 is of tremendous advantage in merchandising this product. The voltage rating of the solenoid coil may vary depending upon field installation requirements. Thus, by having the coil exteriorly of the casing 11, it is possible to substitute coils of different voltage ratings in the field with ease, or in the case of a coil being damaged to replace this coil. In conventional structures, where the coils are mounted within the casing, replacement and interchange of coils becomes a very difficult task. Mounting of the solenoid assembly so as to project rearwardly from the back wall facilitates mounting during installation, since the door material, for example in wooden doors, may be drilled with a standard drill bit to receive the coil housing 52 endwise therein.
The coaction between the slot 47 and pin 50 in the connection between the actuator plunger 49 and the latch frame 38 provides a most important feature of the present invention and results in dead-locking the latch frame in its latching position. More specifically, the spring 58 urges the pin 50 into the slot leg portion 47b, thus preventing counter-clockwise movement of the latch frame towards its non-latching position until the pin 50 is withdrawn from the leg portion 47b, upon energization of the solenoid coil 52, and is free to move into the slot leg portion 47a. This dead-locking feature greatly augments the security provided by the disclosed electric strike release.
From the foregoing description and drawings, it will be clearly evident that the delineated objects of the invention will be accomplished.
Various modifications may suggest themselves to those skilled in the art without departing from the spirit of our invention, and, hence, we do not wish to be restricted to the specific forms shown and uses mentioned, except to the extent indicated in the appended claims.
1. An electric release strike, comprising:
a. a case including a strike plate having an opening therein;
b. a strike bolt pivotally swingable to a position projecting through said opening and to a retracted position;
c. means normally urging said bolt towards its projecting position;
d. latch means pivoted at one side within the casing for swinging movement to latching and nonlatching positions relative to said bolt, said strike bolt and said latch means having pivoted axes oriented in right-angled relation and said latch means having an opposite side normally positioned in the path of swinging movement of the strike bolt from its projecting position to its retracted position, swinging movement of the latch means to its nonlatching position being operative to move said opposite side thereof out of said path of swinging movement of said strike bolt and enable movement of the bolt to said retracted position against the action of said urging means;
e. actuating means electrically energizable to swingably move said latch means to said nonlatching po sition including a movable member connected with said latch means; and
f. means normally dead-locking said latch means against movement away from its latching position.
2. An electric release strike according to claim 1, wherein the latch means includes a frame supported for swinging movement on a horizontal pivot, and said movable member is reciprocably movable in a generally horizontal position above said pivot; and a pin and slot connection between said member and frame.
3. An electric release strike according to claim 2, in which the pin is carried by said member and the slot by said frame.
4. An electric release strike according to claim 3, wherein the slot has a pin receiving end offset portion having substantially coaxial alignment with said member when said latch means are in latching position.
5. An electric release strike according to claim 4, in which said pin is resiliently urged towards a position in said slot offset portion.
6. An electric release strike according to claim 5, wherein said member is connected with a plunger associated with a solenoid coil operable upon energization to move said plunger and member in a direction to withdraw said pin from its dead-locking position in said slot offset portion.
7. An electric release strike according to claim 1, wherein said casing has a rear wall, and said actuating means comprises a solenoid coil and movable plunger assembly mounted at its forward end on said casing rear wall with its longitudinal axis substantially horizontal, whereby said assembly projects rearwardly from said casing rear wall.
8. An electric release strike according to claim 1, wherein the dead-locking means are substantially pickproof and comprise a pin and slot connection between said movable member and said latch means coacting to normally lock said latch means against movement from its latching position in response to a manually applied force against the latch member.
9. An electric release strike according to claim 8, wherein said pin and slot are relatively moved to a nonlocking position in response to energization of said actuating means.