US2566411A - Biparting elevator door interlock - Google Patents

Description

Sept- 4, 1 1 N. R. GUILBERT, JR

BIPARTING ELEVATOR DOOR INTERLOCK Filed May 7, 1949 inventor NICHOLAS R. GU/LBERT, JR.

(Ittorneg Patented Sept. 4, 1951 UNITED STATES PATENT OFFICE BIPARTING ELEVATOR DOOR INTERLOCK Nicholas R. Guilbert, J r., Chestnut Hill, Pa.

Application May 7, 1949, Serial No. 91,949

15 Claims; 1

This invention relates to door locks, particularly to a safety lock for a biparting freight elevator door or the like for preventing operation of the elevator when the door is open as well as for preventing the opening of the door except when the elevator is stopped at or substantially at the floor level.

There have been proposed many types of so called door interlocks adapted for use in connection with elevator doors of various kinds, and some have been reasonably satisfactory under normal conditions. When subjected to tampering, however, they may permit the elevator to be operated while the doors are open, or the doors to be unlocked and opened when the elevator is at some other floor, either of which possibilities may. result in personal injury or loss of life as well as damage to property and equipment.

It is therefore a principal object of the invention to provide an interlock for biparting elevator doors which conforms to or exceeds existing safety standards and which affords maximum security of person and property, even against efforts to jeopardize this security by tampering with the equipment.

Another object is to provide elevator door interlocking mechanismwhich is effective to securely lock the door panels at a floor entrance to the hatchway, to prevent the elevator being moved from the floor leveluntil the panels'have been so locked, and to. prevent the doors from being opened except while the elevator is at the floor level with its driving motor 'deenergized.

Other objects, purposes and advantages of the invention will hereafter more fully appear or will be understood from the following description of a preferred. and a modified embodiment of it wherein reference will be had to the accompanying drawing in which:

. Fig. 1 is a fragmentary view in elevation from within the elevator hatchway of the elevator door interlocking merchanism in operative relation with vertically slidable panels of .a biparting'elevator door of which but fragmentary parts are shown in association with a guide rail of conventional form,

Fig. 2 is a side elevation of the mechanism shown in Fig. 1, with the door panels, as in Fig. 1, closed and locked and Fig. 3 is a view similar to Fig. 2 but with the door panels open.

Referring nowmore particularly to the draw ing it will be understood the door panels P, P, guide shoes S, S respectivelyattached to them, and the guide, {rail IR, which by en agement with the shoes maintains the panels in approximate alignment for parallel movement away from and toward each other to open and close the hatchway entrance may be of any suitable kind or character and form no part of the invention, as the door interlock with which the latter is directly concerned may be readily adapted for effective operation in association and combination with substantially any biparting doors or other oppositely reciprocal elements, or in some instances may be employed in connection with but a single door panel or other element in which case one of the lockin members may be omitted. It will be further understood the interlock as specifically illustrated is designed for employment in connection with an electrically controlled elevator provided with an element known in the art as a retiring cam carried bythe elevator and adapted to be projected outwardly therefrom toward the adjacent hatch wall upon deenergization of the elevator driving circuit to stop the elevator and to be retracted preparatory to moving the elevator to another floor, although in a modification hereafter to be described the interlock may readily be adapted for use in association with a stationary camon the elevator.

Thus in its preferred embodiment the interlock as shown in the. drawing is positioned ad jacent the guide rail R and includes elements adapted respectively to engage a wing arm W on lower door panel P and lock bracket'L on the upper panel P" to lock the panels place-when the doors are closed. The first of these elements, thelower latch arm I, is pivoted in 'aninterlock housing 2 on a transverse pivot pin 3 for oscillatory movement into and out of the path of the wing arm W on panel P while an upper latch arm 4, pivoted for movement about the same axis is movable into and out of the path of lock bracket L on panel P;' if desired springs, not shown, may be provided for urging the latch arms I and 4 toward their locking positions illustrated in Fig. 2 as is customary in many types of door locking devices.

The upper latch arm 4 is provided with an angularly projecting roller arm 5 carrying a roller 6, the position of which is desirably adjustable through the medium of a bolt I and nut 8 to enable the roller to be set at the appropriate posi tion for proper engagement by the retiring or stationary cam carried by the elevator so that when the latter stops at a floor the roller and hence the upper latch arm is moved thereby about the axis of pivot pin 3 from locked position (Fig. 2) to unlocked position (Fig. 3).

The lower latch arm I is provided with a bevel face I!) adapted for engagement by a striker cam I I carried by the lower panel P and provided with any suitable mechanical or manual operating means for swinging it into engagement with the latch to move the latter out of the path of the wing arm W when the door is to be opened. Thus it is apparent that when the door panels are closed, and with the latch arms in the positions illustratedin Fig. 2 thefdoors canngt be opened unless the latch arms are first moved out of the paths respectively of the lock bracket L and wing arm W. Normally these latch arms are moved respectively by the elevator cam (not shown) and striker cam I I, the panels usually being counterbalanced and so interconnected that when both are free to move either will move, in response to movement of the other.

The lower latch arm I however cannot be swung on its pivot to unlock the lower panel, either by operation ofthe striker cam or otherwise, unless the upper latch arm '4 has first been retracted since arm 4 comprises an integral projecting arm I2 within the housing 2 which pivotallysupports a depending tumbler I3 having-'a'n'inclined locking face I4 adapted for engagement by the complementary face I5 of an integral dog- IE on the lower latch arm I thus inhibiting movement of the latter when the parts are in locked (Fig. 2) position. The tumbler I3 is provided with a slot I7 through which a pin It extends into a boss IS on the inner face of the housing 2 whereby the tumbler can move freely substantially parallel to the inner face of the housing but is prevented by the pin and boss from being swung about its pivot by the dog I 6 on the lower latch arm.

There is also provided an electrical circuit in terlock whereby the main elevator-motor driving circuit is held open when the latch arms are retracted, this circuit including a contact unit 28 containing a switch ofanysuitable type connected in the motor control circuit in the usual way and provided with an operating arm 2i adapted for actuation by a Contact control fork 22 which, when the elevator is provided with a re.- tiring cam, is desirably integral with or. relatively immovable with respect to. roller arm 5. for movement therewith to. open said circuit when the roller arm is actuated: bythe retiring. cam. When the elevator is, provided witha stationary cam however, it may be. preferableto. form the con-. tact cont o fork Hintegral with or tosecure it to the lower latch a m Ir and to rearrange th ct n of e witch. in' Contact wait.v 201 sov th main circuit is, interrupted; by, opening of the switch when lower lza igck arm v I, is actuated, instead of b n nte rup e u en a uation f e ro e It sy ss s, beta matte o c o e depending on con ons, which of the said arms is instrumental in actuating the contact control f p ed. he lett r b araneed for si i actuation by one of;t lr em and moves. correspondingly therewith to, actuatethe switch arm -2I to open and close the contact unit switch, and it will therefore, be evident the interlock may be used equally well in associationwith' anelevator provided with a 'ietiring' cam or with one having a correspondingly positioned stationary cam.

,As an additional safety measuremy interlock includes further mechanical means for preventing tampering with the contact unit control to permit operation of the elevator. while the doors are open, said means'beingfully effective to produce this result under. normal conditions but also proof against improper effortsto prevent their own nor-. mal operation" For this purpose there is pivoted 4 in the housing 2 on a pivot pin 25 a rocker 26 having one arm 21 disposed for engagement by the upper edge of wing arm W to swing the rocker clockwise in Fig. 2 as the door closes, a dog 28 carried by the arm and adapted to abut the inner wall of housing 2 limiting movement of the rocker in this direction, and a second arm 29 disposed for engagement by the lower edge of wing arm W to swing the rocker in the opposite direct e t e ev r is ein Q eneehe arm 29 contacts a pin 36 projecting 'from the lower latch arm I when moved in the latter direction, whereby the latch is held retracted by the rocker after the doorhas been opened, and to prevent reverse movement or the rocker while the door remains open'there is pivoted to the lower end of arm 29 o end Of: a holding bar 3| the other end of which all) is pivotally supported on a link 32 pivoted on a boss 33 secured to the adjacent guide rail whereby the bar is constrained to partake of a substantially parallel motion when actuated by the rocker. This bar extends from the rocker arm 29 to a point close to the lower end of the path of travel of wing arm W at which the latter seats on the. usual adjustable sill support X and as the bar lies between said path and the hatch way wall adjacent the door jamb, the wing arm when in transverse alignment. with any part of it prevents the bar from being manually raised to swing the rocker on its pivot and the latter is thereby effectively locked against retraction except when the door is closed orv substantially so and the wing arm thus cleared from transverse alignment with the bar. The bar when the door is open thus maintains the. rocker substantially in the position illustrated in Fig. 3 and under these conditions, the rocker through. engagement with pin 30 holds. the lower. latch arm I retracted and the latter projecting its dog I6. into the path of the tumbler I 3 holds theuppen latch arm 4' retracted even ifthe; retiring or other cam normally so holding it be tampered with, and. while these sev eral parts are thus lacked in position the. switch in contact unit- 20;:also remainslocked to prevent completion of a circuit through the main driving motor to move.- the. elevator.

Wh le the: Operation. of the. apparatus heretofore deseribed'may perhapsbe understood with: out furtherexplanation it may:- be noted that it requiresno special; attentionfrom the elevator operator to i ns l le proper performance ofitsfu nctions as will; be; erident from a brief reference to the various. conditions. which arise automati-w cally; during thecycle. comprising'arrival of the elevator at; therfiooreleizel, opening and closing of the, door panels and; departure; of: the. elevator from the. floor. Ijhus;v as, the elevator approaches the; floor level, the door panelsP; P." and themterlock parts are in the several positions illustrated in'Fig. Asipreviously mentioned theele- Vator may beeqiui-ppedz with. a retiring cam ora stationary one;-- and: substantiallyas it reaches floor level and isbrought to a stop the cam, ii of the former type isaprojected and engages roller 6 to actuate roller arm 5' and" latch arm}; or if the latter type likewise engages theroller and similarly actuates the roller and latch arms; In either case the tumbler I3 is simultaneously and automatically moved out of the'path of dog IE; on

latch arm I, and if the cam is a 'retir ing one the cam II which can ,now swing the latch arm I out of the path of the wing arm W due to the tumbler having been cleared from the path of the latch 'dog I6, As the latch arm I moves, if the interlock is arranged for use with a stationary cam on the elevator the contact unit switch open at this point rather than earlier in the cycle as it does when a retiring cam is used, and in either case as the door panels are moved in opposite directions, either mechanically or manually, the wing arm W moves the rocker 26 on its pivot to the position shown in Fig. 3 and through its subsement alignment with the bar 3| maintain the rocker in position to keep the latch arm I retracted through engagement with the latch pin '30.

Thus the latch arm I cannot be moved manually towards the interior of the hatchway while the door remains open, and as the latch dog I6 therefore lies in the path of the tumbler I3 the upper latch arm 4 and the roller arm 5 are also held retracted, so the contact unit switch is kept open no matter which latch arm is rigid with the contact unit control fork 22, this depending, as noted, on whether a retiring or a stationary cam is used on the elevator to actuate the roller arm 5. When the doors are thereafter closed, as the wing arm W rises along the holding bar 3| and past the now retracted lower latch arm I it engages the upper arm 21 of the rocker 26 which was moved into its path by depression of the lower arm 29 when the door was opened, and as the wing arm clears the notch of the latch arm I the latter can swing to locking position beneath it.

If the elevator cam is a retiring one it is retracted in the normal way on actuation of the elevator control switch and this allows the roller -arm 5 and latch 4 to move to locking position and thereby close the contact unit switch before the main driving motor is energized, usually by automatic' mechanism with which the present invention is not concerned. If, however, a stationary cam is used the contact unit switch is closed simultaneously with the locking of the doors thus allowing the elevatorrto be operated, and as the said cam moves away from the roller 6 the upper latch arm 4 is restored to locking position tolo'ck theupper door panel by engagement with 'lock'bracket L. In either case the parts are thus "restored to the positions shown in Fig. 2 with both door panelslockedl' As the main driving motor circuit is interconnected via armored cable 0 through contact unit 20 the switch in which is opened whenever the door is unlocked either "accidentally or by design itis impossible for the elevator to be operated at any position in the hatchway except when all doors giving access thereto and provided with my interlock are closed 'and locked.

of the panels, such cams or their equivalents however forming no part of the mechanism which actually locks the panels when closed.-

Moreover as the parts are designed to afford adequate rigidity and strength with great durability the interlock, which may readily be incorporated in either old or new elevator installations, when once installed becomes a substantially permanent fixture normally requiring no attention except perhaps an occasional application of lubricant to its bearings to insure continuous service in the performance of its intended functions, while the safety it affords from the standpoint of both mechanical and electric controls meets the standards of the Underwriters Laboratories, required in many jurisdictions to permit erection and operation of elevators.

It will thus be I apparent my interlock is adapted for use with biparting elevator doors of various types and in association with elevator installations of various kinds, and is effective to prevent abnor'maloperation of the elevator and access to the hatchway from a floor in the absence of the elevator'without the slightest impairment of or interference with it normal operation. I

While I have herein shown and described with considerable particularity certain embodiments of the invention and referred especially to their use in conjunction with vertically'slidable biparting elevator doors such as are extensively used for freight elevators and the like it will be understood that the principles of the invent-ion are applicable as well in other installations, particularly those in which positive control of an electric circuit in accordance'with the positioning of a reciprocal element is required; therefore I do not desire or intend to limit or confine the use of the invention to biparting elevator doors, as other uses for mechanism conforming thereto, and changes and modifications in the form, construction and relationship of the several parts of that embodiment thereof herein disclosed will readily occur to those skilled in the art and may be made if desired, without departing from the spirit or scope of the invention as defined in the appended claims.

As my interlock is substantially a self contained unit which in itself embodies all the parts essential for securely locking the door panels when the latter are provided respectively with a locking bracket and a wing arm, or comparable latch engaging devices, it may be readily incorporated in existing elevator installations as well as in new ones during the course of their erection, the latches being adapted respectively for actuation improper sequence by a retiring or stationary scam such as those long heretofore in use for oper- Havin thus described my invention, I claim and desire to protect by Letters Patent of the United States:

1. An interlock for a pair of oppositely reciprocal sliding door panels comprising pivoted latch arms each adapted when in one positon to lock one of the panels against movement in one direction, a tumbler actuated by one of the arms operative when the arms are in said position to inhibit movement of the other arm therefrom, and means carried by said other arm operative when the tumbler has been moved from its inhibiting position and said other arm moved from looking position to engage the tumbler to prevent its return to inhibiting position.

2. An interlock for a pair of oppositely reciprocal sliding door panels comprising pivoted latch arms each adapted when in one position to lock one of the panels against movement in one direction, interengageable means carried by the ar'mscooperative-when the arms are in said position to inhibit movement of one of them therefrom in advance of the other and to restrain return of said other arm to locking position while the first arm remains out of said position.

3. An interlock fora pair of oppositely reciprocal sliding door panels comprising pivoted latch a ms-eac ad edrh s -e s P0 1 to k one of the panels against movement in one direction and movable about a commonaxis between locking and non-locking positions and means actuated by one of the arms when moved from looking to non-locking position operative when the arm is in the former position to inhibit movement'of the other arm to non-locking position and operative when both arms are in the latter position to inhibit movement of the first arm'to locking position. r a. An interlock for apair of oppositely reciprocal-sliding door panelsoomprising pivoted latch arms each adapted when in one position to lock one of the panels-against movement in one direction and movable about a common axis between locking and non-locking positions, means actuatedby one of the arms when moved from looking to non-locking position-operative when the arm is in the former position to inhibit movement of the other arm to non-lookin position and. operative when both arms are in-the latter position to inhibit movement of the-first arm to .locking position, and :means actuated by one of of-the arms operative to interrupt an electrical circuit when said arm is moved from locking to non-looking position.

5. An interlock for a pair of oppositely reciprocal sliding door panels described comprising pivoted latch arms each adapted when in one position to lock one of the panels against move-- ment in one direction andmovable-about a common axis between locking and non-locking positions, means actuated by one of the arms when moved from looking to non-locking position operative when the arm is in the former position to inhibit movement of the other arm to non-locking position and operative when .both arms are in the latter position to inhibit movement of the first 7 arm to locking position, and means en,- gageable with one of the arms and with an element carried by thepanel locking by -said armcherative to hold the latter in non-locking position whenever said panel is in a position other than that in which it is disposed when locked by said arm.

6. In combination with an elevator, an actuating cam carried thereby, a biparting door comprising upper-and lower vertically movable panels at an entrance to the elevator hatchivay, a looking bracket projecting from and movable with the upper panel and a wing, arm projecting from and movable with the lower panel, interlocking means comprising upper andllower .latchxarms respectively adapted to be engaged Joy *the bracket and the wing arm when disposed in the paths thereof, a switch disposed, adjacent the latch arms, means actuated by one- -.of, the latch arms for successively opening. and zclosing. the switch, a roller armprojecting from .the upper latch arm adapted for engagement-Joy thesac tuating cam to movesaidarmrout oflthe path-ref the bracket and a tumbler depending. from the upper latch arm-effective when said-arm-isrin said last mentioned. .pathto .inhibitmovement of the lower latch armout of' the path of the wing arm and effective .when the lower. latch arm is out of the path otthewingarm to inhibitmovement of the upper latch -arm, into'the pathof the bracket.

'7. In combination with an -ele;vator, an actuating cam carried thereby.-and a-bipartingidoor comprising upperand lower vertically movable panels at an .entranceto the, elevator rhatohway \alocking bracket projecting irom and movable with the upper panel and a wing arm projecting from-and movable with the lower panel, interlockingmeans comprising upper and lower latch arms respectively adapted to beengagedbythe bracket and the wing arm when disposed in the paths thereof, a roller arm projecting from the upper latch arm adapted for engagement by the actuating cam to move said arm out of the path of the bracket a tumbler depending from the upper latch arm effective when'said arm is in said path to inhibit movement of the lower latch arm out of thepath of the wing arm and effective whenthe lower latch arm isout of said last mentioned path to in'hibit movement of the upper latch arm into the path of the bracket, and means interconnected with the lower latch arm operable when said arm is out of the path of the wing arm and'th'e wing arm is out of'thepeth ofsaid latch arm to inhibit movement of the latter intothepath of the wing arm.

8. In combination with an elevator, at bipartlng door comprising upper and lower vertically movable door panels at an entrance to the elevator hatchway, a locking bracket projecting from and movable with the upper panel, and a wing arm projecting from and movable with the lower panel, interlocking means comprising upper'and lower latch arms respectively adapted to. be enstaged by the bracket and the wing arm when cl-ispcsed in the paths thereof, means interconmeeting the latch arms operative to inhibit movements otherwise than in accordance within. predetermined cycle which, beginning with the latch arms disposed in positions respectively for engagement by said bracket and said wing arm includes successively movement of the upper latch arm out of thepath oi .thebracket, movement of the lower latch. arm out of the path 101' the wing arm, movement of the lower latch arm intotthe ,path of the Whig-arm and movement of the upper latch arm intothe path of the bracket, and means for moving said latch armsseouen- ,tial-ly out of the paths of the bracket and Wing.

arm.

--9. .In combination with an elevator, .an actuating oam carried thereby and a :biparti'ng door comprising upper and lower vertically movable door panelsat an ent'rance. to the elevator h'atfdhway, a locking bracket projecting .from ,andlmovable with :the upper panel, awing armprojecting from and movable with. the lower panel, interlocking meansscomprising upper and lower latch arms respectively adapted to .be engagedbyithe bracket andzthe wing arm whendisposedinuthe paths thereof, means interconnecting .the latch arms operative to inhibit their movements other wise: than in accordance with. a predetermined :eyclewhich, beginning with the latch arms-dis- ;posed :in positions respectively for engagement by said bracket and said wing arm, includes-successively movement vof the. upper latch arm {out or the: path; of the '-.bracket. :movement of. the lower latch arm out'of the path of the wingrfarm, movement 'of theazlower latch arm into .the .pathofthervwing farm and movement of thenpper latch: arm :into the. path .of the bracket, {and means engageable with :the wing .armionrestreiim Iing movement of=the lower latch armaintoethe path :of the-wing armaafteritlhas been .moved 10-. :In'combination .witha slidableelevatorfioor panel and a-wingarmoarried thereby, la; pivoted latcharm projectib'le into and out of the path of the wing arm when the panel is in closed position, a movable bar extending parallel to said path, pivoted links supporting the bar operative to maintain it in parallelism with said path during movement transversely thereof, and means projecting from the latch arm engageable by one of said links to maintain the latch arm retracted from the path of the wing arm when the bar has been moved in one direction transversely of said path, the wing arm when the panel is in open position lying adjacent said bar in a position to obstruct its corresponding movement in the opposite direction.

11. An elevator door interlock comprising movable latch arms respectively adapted in one position to lock one of the panels of a biparting elevator door when closed, and means interconnecting the latch arms operative to hold one arm in said position when the other arm is in the corresponding position and to hold said other arm in a different position when the first arm is in a correspondingly different position, said means comprising a latch dog movable with the first arm and a tumbler engageable by the dog pivoted to and movable with the second arm and disposed in the path of the dog when the arms are in said first position, said dog being disposed in the path of the tumbler when the arms are in the second position.

12. An elevator door interlock comprising movable latch arms respectively adapted to lock one of the panels of a biparting elevator door-when closed, and means interconnecting the latch arms operative to hold one arm in looking position when the other arm is in the corresponding position and to inhibit the return of said other arm to locking position when said first arm is in non-locking position, said means comprising a latch dog movable with the first arm and a tumbler engageable by the dog pivoted to and movable with the second arm and disposed in the path of the dog when the arms are in said first position, said dog being disposed in the path of the tumbler when the arms are in the second position.

13. An elevator door interlock comprising mov-- able latch arms for releasably holding closed the panels of a biparting elevator door, means interconnecting the latch arms operative to lock one arm in position to so hold one panel when the other arm is in holding position with respect to the other panel, means for successively moving said last mentioned arm and then said first arm to other positions to release the panels and, means carried by said last mentioned arm for holding it in said other position when the first arm is in its said other position.

14. An elevator door interlock comprising movable latch arms each adapted to releasably hold closed one of the panels of a biparting elevator door, means interconnecting the latch arms operative to lock one arm in holding position when the other arm is in corresponding position, means operable successively to move said other arm and then said first arm to non-holding positions and means for maintaining the first arm in its non-holding position while the corresponding door panel is open comprising a detent projecting from the arm, a pivoted lever engageable with said detent and means for actuating said lever.

15. In a door interlock for biparting elevator doors comprising opposed panels and means supported by each panel adapted to engage a latch, upper and lower latches respectively adapted for engagement by said means to lock the panels and interlocking means imposing a predetermined sequence of operations on the latches in the cycle of successively unlocking and relocking the panels, comprising a tumbler carried by one of the latches, and a latch dog carried by and movable with the other latch engageable with the tumbler to inhibit movement of the latter latch when the tumbler and latch dog respectively are in predetermined positions and to inhibit movement of the tumbler-carrying latch when. the tumbler and dog respectively are in other positions.

NICHOLAS R. GUILBERT, JR.

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

UNITED STATES PATENTS Number Name Date 543,569 Clark July 30, 1895 1,381,262 Wexler June 14, 1921

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