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Publication numberUS508518 A
Publication typeGrant
Publication dateNov 14, 1893
Filing dateMay 19, 1893
Publication numberUS 508518 A, US 508518A, US-A-508518, US508518 A, US508518A
InventorsHarry T. Johnson
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 508518 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)



SPECIFICATION forming part of Letters Patent N 0. 508,518, dated November 14, 1893.

Application filed May 19, 1893. seminar/e745. a. moan To 11. whom it. may concern:-

Be it known that LVHARRY T. JOHNSON, a citizen of the United-States,-and a resident of the city, county, and State of- New York, have invented certain new and useful Improve. ments in Electric Door-Openers, of which the following is a full, clear, and exact description, reference being had to theaccompanying drawings, forming partof this specification.

My invention relates to that class of electric locks popularly called door openers, which are generally applied to the main doors of flats and apartment houses, and which, through the agency of an electric magnet operated from the ditferentrooms or apartments in the building, may be actuated to release thelatch of the door and permit it to be opened.

The class of apparatus to which my-invention pertains has generally comprised a mov-.

able latch block or keeper for the latch, normally locked to hold the latch and prevent the doorfrom being opened, an electro magnetoperated by circuit closing devicesar; ranged as desired at different points in the building, and mechanism intermediate thev armature of the magnet and the latch block by which, when the circuit through the mag; net is closed and its armatureattracted, the

latch block is unlocked and may be rotated sufficiently to release thelatch when pressure is applied tothe door, and suitable devices, such as retractile springs, tQj return the parts to their normal position, when the circuit through the magnet coils is broken. The mechanism just described has usually been secured to the door jarnb in a position to cooperate with the reciprocating latch carried by the door, and so constructed as -to be immovable from the outside of the door in a manner well understood. mechanism may be'operative, it is absolutely necessary that the door should be moved suf- .ficien tly to start the latch block from its nor:

mal position before the intermediatel-ocking mechanism returns to its locking position, and to meet this requirement, various mechanical devices have been employed, the one most generally in use consisting of a spring pressed plunger secured to'the door or the jamb, and arranged to exert a constant pressure against the door, so that when the locking mechanism is disconnected or disengaged from the In order that such latch block, the spring will throw the door open sufficiently to startthe latch block from its normal position, and .thus prevent the return of the locking mechanism to its normal 'position until the doorlatch has been pushed entirelyclear of the. latch blocker keeper;

but these devices havelnotproved entirely satisfactory. They are unreliable, particularly in wet weather, when the door will often stick, and the pressure of the spring be insufficient to release it; and furthermore, they deface the door or the casing and increase the number of parts required to put the apparatus in working condition.

The principal object of my invention is the provision of means for overcoming these objections, and a further object thereof is the provision of novel mechanismfor actuating the latch releasing devices, whereby I attain simplicity of construction, strength of parts, and positive and reliable action thereof.

To these ends my invention consists in the combination with mechanism for releasing the latch block or keeper, of a permanent magnet forholding such mechanism out of its locking-position until released by the movement fofthe (1'0'OI.". 1

It also i'con'sists in the novel details of constructiou'and combination and arrangement ofp'arts hereinafter described and specifically pointed out in the claims. In the accompanying drawings, Figure 1 is a View in elevation showing my improved ap- 'paratus inserted in a door jamb. Fig. 2 is a similar view showing the parts in a different position. Fig. 3 is a cross section on the line 33 (Fig. 1). Fig. 4 is a cross section on the line 4:at (Fig. 2). Fig. 5 is a similar view showing the armature about to be moved, by the movement of the latch block, from'the position it occupies when in contact with the permanent magnet. Fig. 6 is a cross'section on the line 66 (Fig. 1) showing a modified construction, and Fig. 7 is a partialvie. in elevation showing another modificatio The form of mechanism which at the pre ent time I preferably employ isLilIustrate in Figs. 1- to 5, but many modifications may e made therein, some of the most obvious being illustrated in the other views.

It will also be understood that my-inven tion may, in view of the following-description thereof, be applied to most of the door open.- ers now in common use without the exercise of more than ordinary mechanical skill.

In the form of apparatus shown in Figs. 1 to 5 A represents the jamb or casing of the door, which is mortised to receive the supporting frame B of the apparatus. Theframe B is provided with a face plate of the usual form which is flush with the door jamb, and it is also constructed with a web I), which serves as a support for one end of the pivots on which the operating mechanism is mounted. The latch block or keeper is mounted on the pivot c, and is normally held in the position shown in Figs. 1 and 3 by the spring a. The latch block may if desired be provided with the striking roller 0 A link D is pivoted at one end to the inner edge of the latch block 0, and at the other end to the swinging end of the link D. The opposite end of the link D is pivotally secured to the frame B. The links D and D thus form a toggle joint which, when straightened out, and the locking lever E, to be presently described, is in its normal position, will hold the latch block 0 firmly in position and prevent the release of the latch F. The inner end of the link D is provided with a toe d which, when the toggle joint is straightened out or extended, as shown in Figs. 1 and 3, will rest against a stop d formed on the link D, and prevent the toggle from swinging over its center. The locking lever E is pivoted in the frame B, and a spring e tends to swing its lower end toward the link D. The lower end of the lever E is notched or rabbeted to fit over the swinging end of the link D, in which position it is normally held by the spring e, thereby normally locking the toggle in its extended position (shown in Figs. 1 and 3) and preventing the latch block from rotating to release the latch. The locking lever E is also provided with an arm 6' which projects into the path of the pivoted armature G which is arrangedin proximity to the poles h of the electro magnet H, and which is attracted thereto when the coilsof said magnet are energized by closing the circuit. The

' locking lever E is also provided with an extension 9 which is moved into the path of the rotating latch block 0, so that when the latter is rotated, the lever E and arm 6 will be moved thereby, as will be more fully hereinafter explained. i

The means employed by me for holding the mechanism above described out of its loo-kin g position until released bythe movement of the door, is a permanent magnet, and preferably I form such permanent magnet by connecting the poles h of the electro magnet in magneticcontact with a plate or bar I of hard steel which forms a permanent magnet, so

I that the said poles h serve as polar extensions the coilsof the electro magnet, the attraction exerted by the permanent magnet will hold it there after the coils of the electo magnet are de-energized by the interruption of the current, and until it is mechanically released, as hereinafter set forth. A spring g tends to hold the armature G away from the poles of the magnets, but this spring, while of sufficient strength to hold the armature in the position shown in Figs. 1 to 4: when the coils of the electro magnet are de-energized, is not strong enough to resist the attractive force thereof when the circuit is closed, or the attraction of the permanent magnet when the armature is in contact with the poles h. The coils of the electro magnet are included in a circuit comprising a primary battery or other source of electrical energy, and circuit clos' ing devices locatedwhere desired in the dilferent rooms or apartments of the building, in the usual way.

The operation of my improved device, as herein illustrated, is as follows: The door being closed, the latch F lies behind the latch block 0, and the difierent parts of the mechanism are in the position shown in Figs. 1 and 3. The latch F is of the well known construction which cannot be reciprocated from the outside, and the door is therefore firmly locked so long as the latch block 0 is held in said position. When it is desired to release the latch from any station in the building, the circuit closing device, which is usually an ordinary push button,is manipulated to close the-circuit through the coils of the electro magnet H. The armature G is then attracted toward the poles h of the magnet, and in its movement strikes the end of the arm 6 secured to the lockin g lever E and carries the notched lower end of the lever E clear of the inner end of the link D. The closing of the circuit carries the armature G into contact with the poles h, and it is held there by the attractive force of the permanent magnet after the circuit is broken. The lever E is thereby held out of engagement with the tog gle link D, and if pressure be applied to the door, the latch F will engage with the latch block 0 and rotate it in the direction to release the latch. Before the latch block is thus rotated sufficiently to release the latch entirely, its inner edge will strike the extenbetween the armature and the poles his thus broken, the locking lever E will, under the action of spring e,swing inwardly beyond the position shown in Fig. 3 to that shown in Fig. 4. In this manner the mechanism by which the latch block is locked and unlocked,

I through the electro magnet, and themoving is, by the movement of the door, released from the position in which itis held by the permanent magnet." The further movement of the door will rotate the latch block 0 suf ficiently tov release -.the latch F entirely. As

said end of link D registers with the notchformed in the lower end of lever E, when the spring e will throw the lever back so that the notch will swing into place over the end of thelink D, and the parts will be locked so that when thedoor is closed it will be locked as before, and will remain locked until the circuit through the magnet coils is again closed, when the operation above described will be repeated.

It will be observed that I have entirelyobvia'ted the necessity for providing. any mechanical device for throwing the .door away from its. jam'b simultaneously with .the closing of the circuit, because in my device the permanentmagnet holds the locking-lever out of its locking, positionuntil the door is.

moved, irrespective of the length of timethat may elapse between the breaking of the circuit of the door, and thishighly desirable result is obtained without the employment of any mechanism except the small pieceof steel re-.

quired. for the permanent magnet,- which op-' crates automatically without friction, which requires no careful. adjustment, and which will.

never needrepairs, or readjustment.

As previouslystated, many modifications may be made in the. details and mechanical features of the apparatus without departingfrom the spirit of myinvention, and inFigs. 6 and 7 I have illustrated two modified arran ements of the magnets.

In Fig. 7 instead of connecting the magnetized bar 'orplate I to the poles h, which also serve as the poles of the electro.magnet,-

the electro magnet.

In Fig. 6 is illustrated still anothermodification, in-which the pivotedarmature G is made of hard steel instead of soft iron, as in the form of apparatus first described, and serves as the permanent magnet. It will also be understood that one or both of the cores of the electro magnet may be of hard steel,

in which case they will formv a permanent magnet.

operate in the same manner as that form of which I have already given a detailed de- These modified forms of' apparatus 1 'scription, so that no further description thereof is necessary. I

It will of course be understood by those skilled in the art thatthe permanent magnets are constructed of hard steel such as is usually employed for permanent magnets, and although it may be done if desired, it is not at all essential that they should be magnet -i zed before being placed in the apparatus, because, by contacting with the poles of the electro magnet when the coils thereof are .active, they will immediately become permanently magnetized. Thus if the parts I have designated as permanent magnets are not permanent magnets when placed in position, they will become such the first time the ap-- paratus is used.

Besides the advantages derived by the employment of the permanent magnet for holding the locking mechanism out of its locking position, until the door is moved, as herein set forth, the mechanical details and arrange-- ment of parts which I herein show and preferably use, possess decided advantages in that the construction is strong, durable, and so simple that the apparatus is not likely to get out of repair, and will operate promptly, and reliably on. a comparatively feeble current.

Havingthus described my invention, what I claim as new, and desire to secure byLetters Patent, is l t 1. In a door opener, the combination of a movable latch block, mechanism for locking and unlocking the same, an electro magnet for actuating said mechanism to unlock the latch block, and a permanent magnet for holding said mechanism out of its locking position until released by the movement of the door, substantially as shown and described.

2. In a door opener, the combination of a movable. latch block, a lever for locking and unlocking-said latch block, an electro magnet arranged to throwsaid leveroutof its locking positionand into the path of the latch block when the current is applied, and a permanent magnet arranged to hold said lever in its position in thepath of the latch block until released from said position by the movement of the latch block, substantially as shown and described. V

3. In a door opener, the combination with an electro magnet having a pivoted armature, of a pivoted latch block, a spring pressed lever for locking and unlocking said latch block, which lever lies in its locking position in the path of the pivoted armature, and in its unlocking position in the path of the pivoted latch block, and a permanent magnet for holding said lever in its unlocking position until moved therefrom by the movement of the. latch block, substantially as shown and described. V Y

4.. In a door opener, the combination of a.

pivoted latch block, a toggle joint connected at one end to the latch block, andat theother end to its supporting frame, a spring pressed lever normally engaging with said toggle and locking the same in an extended position, an electro magnet arranged to move said lever from its locking position and into the path of the latch block when the current is applied, and a permanent magnet for holding the latch block in the position to which it is moved by the electro magnet until released from such position by the movement of the latch block, substantially as shown and described.

5. In a door opener, the combination with a movable latch block, of an electro magnet having its poles secured to a permanent magnet, and mechanism intermediate the electro magnet and the latch block for unlocking the latch block when the coils of the electro magit out of engagement with the toggle when 30 the magnet coils are energized, substantially as shown and described.

HARRY T. JOHNSON. Witnesses:



Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4514001 *Jun 14, 1984Apr 30, 1985Segutronica, S.A.Electro-mechanical lock
US4626010 *Jan 28, 1986Dec 2, 1986Hanchett Entry Systems, Inc.Concealed door release mechanism
US5729198 *Oct 25, 1996Mar 17, 1998Gorman; Kim RamseyWireless residential door unlatch system
US6580355Jun 11, 1999Jun 17, 2003T.K.M. Unlimited, Inc.Remote door entry system
US7032418 *Apr 21, 2004Apr 25, 2006Sargent Manufacturing CompanyVertical door locking system
US20050235711 *Apr 21, 2004Oct 27, 2005Secure Access Lock, Inc.Vertical door locking system
Cooperative ClassificationY10S292/49, E05B47/0047