US3340710A

US3340710A - Time operated and/or remote controloperated electro-mechanical lock

Info

Publication number: US3340710A
Application number: US527312A
Authority: US
Inventors: O'brien Eugene
Original assignee: COMMAND LOCK Inc
Current assignee: COMMAND LOCK Inc
Priority date: 1966-02-14
Filing date: 1966-02-14
Publication date: 1967-09-12
Anticipated expiration: 1984-09-12

Description

E- O'BRIEN 3,340,710

OPERATED Sept. 12, 1967 TIME OPERATED AND/OR REMOTE CONTROL 7 ELECTRO-MECHANICAL LOCK Filed Feb. 14, 1966 3 Sheets-Sheet 1 ---ETo Loich BOW INVENTOR. EUGENE 0' BRIEN ATTORNEYS E. O'BRIEN 3,340,710

OPEHATED Sept. 12, 1967 TIME OPERATED AND/OR REMOTE CONTROL ELECTRO-MEGHANICAL LOCK 5 heets-Sheet 8 Filed Feb. 14, 1966 Tmw HOAC.

INVENTOR. EUGENE O'BRIEN ATORNEYS Sept. 12, 1967 TIME OPERATED AND/OR REMOTE CONTROLOPEHATED Filed Feb, 14, 1966 E. Q'BRIEN ELECTRO-MECHANICAL LOCK 3 Sheets-Sheet 5 I INVENTOR EUGENE O'BRIEN ATORNEYS United States Patent 3,340,710 TIME OPERATED AND/0R REMOTE CONTROL- OPERATED ELECTRO-MECHANICAL LOCK Eugene OBrien, Philadelphia, Pa., assignor to Command-Lock, Inc., a corporation of Pennsylvania Filed Feb. 14, 1966, Ser. No. 527,312 The portion of the term of the patent subsequent to Feb. 14, 1983, has been disclaimed Claims. (Cl. 70-271) This is a continuation-in-part of my copending patent application Ser. No. 324,012, filed Nov. 15, 1963, now US. Patent 3,234,766.

This invention relates to a time controlled lock, the primary object of which is toprovide a construction in which the lock is automatically closed at a pre-set time and automatically re-opened after a pre-set interval thereafter, the lock being key or manually operable only by authorized personnel in said interim. It also relates to a remote control-operated lock in which the opening and closing thereof is automatically effected by a means other than a timer, such as by manual, pressure or temperature operation. A general object of this invention is to provide a new and improved electrically operated lock.

Another object of the invention is to provide a time controlled lock of the character described in which the latch bolt of the lock is extended into the closed or retracted into the open position by a timer actuated motor in such a manner that the motor shuts 01f at the end of a movement corresponding to the travel of the latch bolt thereby utilizing electrical energy only for the short time corresponding to that required to extend or retract the bolt.

Another object of the invention is to provide a time controlled lock of the character described in which the timer actuated motor is operatively connected to the latch bolt by a means which permits the retraction cycle to complete itself and which cuts off the motor even though the latch bolt may be temporarily restrained from movement, as by jamming in the keeper, said means storing the retraction energy and acting to move the bolt to the retracted position when the restraining force in the keeper is eventually released.

Another object of the invention is to provide a time controlled electromechanical lock which does not necessarily rely upon batteries as a source of current and which employs instead circuits of opposite polarity and switches therein in which are operatively connected an electrical source, a reversible motor and the lock bolt in such a manner that at the end of each stroke of the latch bolt a switch is actuated to break one of the circuits and cut olf the motor but move to such a position that when the timer re-activates the motor at the pre-set time the opposite circuit is automatically closed.

Another object of the invention is to provide a timer actuated electromechanical lock which can be opened mechanically from the inside and by key operation from the outside only by authorized personnel during the interval when the lock has been pre-set to remain closed.

Another object of the invention is to provide an electromechanical lock which can be actuated by a remote control push button. Another object is to provide a timer actuated electromechanical lock which can be opened with a mechanical key only during the intervals when the lock has been pre-set to be so opened.

These and other objects of the invention will become more apparent as the following description proceeds in conjunction with the accompanying drawings, wherein:

- FIG. 1 is a perspective view of the lock shown installed;

FIG. 2 is a side elevational view of the instant lock,

3,340,710 Patented Sept. 12, 1967 the cover having been removed to disclose the working parts;

FIG. 3 is an exploded perspective view of the latch bolt and slide actuating bar therefor;

FIG. 4 is a diagrammatic view of the timer, motor, latch bolt actuator and circuit therefor;

FIG. 5 is a schematic side elevational view of a modified form of this invention; and

FIG. 6 is a schematic side elevational view of another modified form of this invention.

Specific reference is now made to the drawings in which similar reference characters are used for corresponding elements throughout.

The lock is generally indicated at 10 and comprises a housing 12, preferably rectangular, and a cover 14 therefor which encloses the lock mechanism. The rear plate 16 of the housing is itself secured as by screws 18 to a door 20 in any desired position so that one of its side walls 22 is adjacent the vertical edge of the door and proximate to a suitable keeper 24 which has been mounted on the door jamb 26.

The lock mechanism is itself secured upon a substantially rectangular mounting plate 28 which is smaller than the opening 30 closed by the cover 14 so that the mounting plate can be readily slipped into the housing and there secured. Thus, where the door structure makes it diflicult to install the entire lock as a unit, by the present arrangement, first the housing 12 can be readily secured and then the mounting plate. Mounted on and extending perpendicular to the rear housing plate 16 and through a hole in the door is a continuous wafer type lock 32 having a rotatable plug 34 which is operable by a key 36 that is removable in two positions apart. The plug extends into the housing and through a cut-out 38 in the mounting plate 28 and secures a cam 40 on its inner end.

The mounting plate 28 has an upstanding wall 42 with a central opening 44 through which extends a conventional tubular-type spring latch. The latch includes a tube 46 secured to a plate 48, the latch bolt 50 being slidable in the tube and normally urged by a spring 52 in the tube towards the extended or closed position through a hole provided in the plate 48 and an opening in the side wall 22 of the housing thence into the keeper. The wall 42 of the mounting plate 28 is secured by screws 54 to the latch plate 48 and then further recessed screws 56 are made to extend through the side wall 22 of the housing, the plate 48, and the wall 42. Additional screws 58 are used to fix the mounting plate 28 in its final position in the housing.

The inner end of the latch bolt 50 includes a flattened reduced shank 60 and a laterally enlarged head 62. A latch bolt actuator 64 is provided which extends vertically across the mounting plate 28 and consists of a member which is substantially U-shaped in cross-section having a pair of spaced

plates

66 and 68 connected by a web 70, the plate 68 having a laterally extending enlarged portion 72 provided with an open-ended slot-74 for receiving the shank 60 and head 62 of the latch bolt 50 and etfect coupling of the actuator 64 to the bolt. The

plates

66 and 68 are spaced apart a distance greater than the total movement of the latch bolt 50. The mounting plate 28 secures a pair of upstanding spaced bars 76 through which extend, slidably, rods 78 secured to the actuator 64 to guide the latter in its slidand by a threaded member 82 which engages the mounting plate 28 and rear housing plate 16, the latter be-' ing locked in place by a key 84. To one side thereof a shaft 86 is rotatably mounted on the cover and extends into the housing, the inner end thereof securing a cam 88 and the outer end'an operating handle 90.

A spring 92 connects the cam with the cover and urges it away from the actuator. Thus, it will be seen that rotation of the handle 90 in a counter-clockwise direction will cause the cam 88 to engage the actuator 64 and retract the latch bolt. Similarly, key operation of the barrel 34 will cause the cam 40 to engage the actuator 64 and retract the latch bolt.

Mounted on the plate 28 is a reversible DC motor 94 whose shaft drives gearing 96, see FIG. 4, one of which is a sector gear 98 having an upstanding arm 100 which extends through the motor casing, as seen in FIG. 2. Such a motor and associated gearing is commercially available as a Duramite-Multi Servo unit supplied by Bonner Specialties of Los Angeles, Calif. A spring 102 is terminally hooked as at 104 to the arm 100 and behind the plate 66 as at 106 through which it is freely slidable. The spring rating of spring 102 is such that it is stronger than the latch spring 52 but weaker than the motor and gears for a purpose later to appear.

A conventional timer 108 is provided in the form of an electrically operated clock having trippers on its clock face which can be set at desired time intervals to open and close the instant lock, the trippers actuating a single pull, double throw toggle switch 110. Such a timer is available from Tork Time Controls, Inc., of Mt. Vernon, N.Y., as Tork Time Switch, Model 7120. The switch 110 is interposed in two circuits of opposing polarity, 112 and 114, each including the motor 94 and a shunt switch 116 energized at the end of each stroke of the sector gear 98 to break the circuit to the motor and prepare the opposing circuit for closure by mere actuation of the toggle switch 110 at the next time interval.

In use, suppose one wished to arrange for the lock to automatically close at pm. and automatically reopen at 9 am. the next morning. One of the trippers of the timer 108 is set at 5 pm. and the other at 9 am. and the clock is set at the correct actual time. When the first tripper arrives at 5 pm. it throws the pole of the toggle switch 110 to the position to engage the terminal 118 and close the circuit 112 driving the motor in one direction and through the

gearing

96, 98 the arm 100 from left to right on FIG. 2 or from a remote to a close position with reference to the keeper. In so doing, the tension on spring 102 is released allowing the compression latch bolt spring 52 to take over and urge the latch into the extended or closed position, the latch pulling the actuator 64 along. At the end of its travel, the sector arm 100 actuates the shunt switch 116 to break the circuit 112 by causing its pole to move away from terminal 120 which it had previously contacted, thus cutting off the current to the motor. At the same time, the pole of switch 116 moves to engage the terminal 122 of the shunt switch which would normally close the circuit of opposite polarity 114 but for the fact that the pole of the toggle switch 110 has not yet engaged the second terminal 124. When the second tripper arrives at 9 a.m., it actuates the pole of the toggle switch 110 to engage the terminal 124 thereby automatically completing the circuit to the motor and reversing its rotation. In so doing, the sector arm 100 moves away from the keeper or from right to left of FIG. 2 extending the spring 102 somewhat which in turn pulls the actuator 64 to the left or away from the keeper and retracts the latch bolt 50 against action of its compression spring 52. At the same time, the pole of shunt switch 116 moves olf terminal 122 and engages terminal 120 to prepare the other circuit 112 to be closed only by the action of the timer tripper when it arrives at the next pre-set interval.

In the event that the latch bolt is jammed in the keeper for some reason, the arm 100 will complete its stroke to the left and shut off the motor while the spring 102 is fully extended. The spring therefore acts to store the retraction energy and whenthe jamming is mechanically released, the spring 102 will itself retract the actuator 4 64 and latch bolt 50, thus preventing overload on the motor.

In the further event that an authorized person inside the enclosure wants to release the lock from the inside, a solenoid 126 may be provided in the housing whose core 128 is operatively connected by a wire 130 to the plate 66 behind which it is hooked as at 131 and through which it is freely slidable, there being a push-button switch 132 at any desired location to close the circuit to the solenoid and thereby retract the actuator 64 and latch bolt 50. If desired, the solenoid can be located outside of the housing and operatively connected to the actuator 64 by other means.

When the bolt 50 is in its extended position and engages the keeper, the actuator 64 is at its furthest position towards the keeper or to the left of FIG. 2. If the timer has acted to cause the latch bolt to lock and has not yet arrived at the time to open it, those in the enclosure can let themselves out by rotating the handle so that cam 88 abuts the plate 68 of actuator 64 to retract it and the latch bolt. From the outside this can be effected only by an authorized person having key 36 which when used to rotate barrel 34 in one direction will cause its cam 40 to abut the plate 68 of actuator 64 to retract it and the latch bolt 50. The conduit 134 from the timer 108 enters the housing through a grommeted opening in the side Wall 136 of the housing opposite wall 22. Also, because the solenoid wire and retractor spring 102 are freely slidable through plate 66, the latch bolt can be manually retracted without any resistance from either the wire or spring and the latch bolt can be retracted by the solenoid without any resistance from the retractor spring 102.

It should be understood that the switch 110 can be operated by manual, pressure or temperature means, instead of a timer, in which case the mechanism becomes a remote-control-operated electro-mechanical lock. For the purposes of manual remote operation, it has been found desirable to provide a set of indicator lamps for the operator and associated switches at the lock. For example, a switch has been provided in keeper 24, which is efiective to energize a lamp when the bolt 50 is retracted; another switch has been provided within housing 12 to be operated by actuator 64 in its different positions so that a lamp is lit or not depending on the operated condition of the actuator. Thereby, the operator is able to monitor the condition of the lock at all times.

As shown in FIG. 4, a key-operated switch unit in lock housing 12 provides a secondary control of the motor 94. The unit 150 includes a single-pole, normallyopen switch 152 that is connected in series in the lockopening circuit 114; for example, it may be connected as shown between the motor 94 and switch 116. The unit 150 also includes a suitable operator for the switch 152, one form of which is a mechanical lock and key 154, which serves to mechanically actuate switch 152 when inserted therein. The unit 150 may take the form of any suitable key-operated switch; for example, the cam 40 actuated by key 36 may be used to operate a simple single pole switch when it is rotated a quarter-turn. Such a key operator unit may be installed at any desired location within the housing 12 where it does not interfere with the mechanism, or such a key operated unit may be installed at a separate location on the door or door jamb and appropriate wiring connections made to form an appropriate control circuit such as the circuit illustrated in FIG. 4.

With the switch unit 150, the operation of the lock under the control of the timer 108 is similar to that described above during the closing operation via circuit 112, which is effective to extend the bolt 50 into keeper 24. However, when the timer operates the switch 110 to the position illustrated in FIG. 4 to initiate retraction of the bolt 50, the circuit 114 is not completed to energize the motor 94 until a key 154 is inserted in unit 150 to close the switch 152. When the switch 152 is closed, the motor is energized and the bolt 50 is retracted in the manner described above. Thereby, a double security control of the lock is provided, and personnel may be supplied With copies of the key 154 that are only ef ective to open the lock during the time intervals for opening established by the timer 108. The switch 152 does not prevent proper closing operation by the timer 108 to extend the bolt 50; and once so extended, the key 154 is inefiective to energize the motor 94 and open the lock until timer 108 throws switch 110 to the bolt retraction position shown in FIG. 4.

In FIG. 2, spring 160 is connected between a pin 162 fixed to mounting plate 28 and the arm 100 of motor 94, and acts in a direction to assist the motor 94, acting via arm 100, in extending spring 102 or compressing bolt spring 52. The balance spring 160 is extended by the arm 100 when motor 94 is operated for actuation of the bolt 50 to its extended position. The extension of spring 160 stores much of the energy of the motor during that portion of the operation. Upon operation of motor 94 to retract the bolt 50, spring 160 assists arm 100 in the retraction operation, and the energy stored in the spring 160 is transferred to coupling spring 102 or to the "bolt spring 52, one of which is extended during this bolt retraction operation depending on whether the bolt 50 is struck in the keeper 24, or whether it is readily retracted. The balance spring 160 has less spring force than the coupling spring 102 and serves to balance the load on the motor 94 to require approximately equal drive of the motor in both the bolt-extension and bolt retraction operations.

Without the balance spring 160, the bolt spring 52, compressed by the retracted bolt 50, stores the motor energy and assists the motor in the bolt-extension operation; while the spring is a load during bolt retraction. Since the motor operation, without the balance spring 160, is not the same for bolt retraction as bolt extension, one can provide a smaller energizing current during the boltextension operation to compensate for the unbalance and provide smoother operation. However, it has been found that the balance spring 160 serves not only to balance the load on the motor for the most part, but also during normal operation, the spring 160 tends to reduce substantially the load on motor 94. The reduction in load results from the transfer of energy from the balance spring to the bolt spring 52 during bolt retraction, and back from the bolt spring to the balance spring during bolt extension. When the bolt 50 sticks in the keeper 24, energy i transferred from the balance spring 160 to the coupling spring 102, and after the bolt is released from the keeper 24, from the coupling spring 102 to the bolt spring 52 to retract the bolt. When motor 94 is operated for bolt extension and the bolt 50 is blocked from entering the keeper 24, the motor 94 has the additional load of extending balancing spring 160 since it is not assisted by bolt spring 52 at that time. However, this is an infrequent occurrence, relatively speaking, so that the overall loading of the motor 94 is substantially reduced by use of the balance spring 160.

A modified form of the invention is illustrated in FIG. 5, in which parts corresponding to those described above are referenced by similar numerals with the addition of a prime A bolt 50' is biased outwardly in the extension direction for engagement in a keeper (not shown) by a pair of compression springs 52. Each of these springs 52 lies between and bear against a shoulder on the 'bolt 50 and a guide post 164, which post is fixed to the lock mounting plate 28' and slidably receives a guide rod 166 that is secured to the bolt 50 and passes through spring 52. A pull rod or arm 100" is slidable between guides 168 and within a chamber formed within a yoke extension 170 of the bolt 50. A compression coupling spring 102' bears between an inner shoulder of the yoke 170 and a shoulder 172 at the end of pull rod 100" and tends to bias the bolt 50 in the retraction direction. At the end of pull rod 100", a slotted crosshead 174 receives a pin 176 eccentrically located on a rotatable disk 178, the center of which is rotatable by way of a shaft coupling to a motor 94', which includes an appropriate gear box 179. The motor 94' may be reversible motor or it may be a unidirectional motor that can be alternating current -or direct current energized. A balance spring 160', shown as an extension spring, is connected between a fixed post 162 and the cross-head 174 and biases the pull rod in the bolt-retraction direction. The crosshead 174 operates a toggle-switch 116 when it is moved to either of its extreme positions by way of two

operator arms

182 and 184 connected to the pole of switch 116, which are respectively engaged by the crosshead 174 at opposite ends of its path.

In operation, the bolt 50 is biased by springs 52 to its extended position for engagement in the keeper in the position illustrated in FIG. 5. Where motor 94' is a reversible direct current motor, the circuit FIG. 4 may be used in the manner described above, in which batteries (or any other equivalent power supply) of opposite polan'ty (as shown in FIG. 4) may be used to energize the opening and

closing circuits

114 and 112, respectively, and switch 116' is used in place of switch 116 in FIG. 4. Where an A-C motor is used, it is operated in a single direction, and the direct-current power supply, shown as batteries in FIG. 4, may be replaced by an A-C line with the pair of A-C power terminals being connected in reverse fashion to the two

circuit sections

112 and 114, or coupled thereto by a transformer with separate secondary windings for the two

sections

112 and 114. In that arrangement, the motor 94' is energized via circuit 114 to retract the bolt 50, and via circuit 112 to extend the bolt 50'. That is, when energized by a circuit 114, motor 94' rotates disk 178 a half-cycle, at which pin 176 is in the phantom position 176', to move crosshead 174 and pull rod 100" to the left, compress coupling spring 102, and pull bolt 50' to the retracted position against the bias action of springs 52'. The chamber of yoke 170 is somewhat longer than the required bolt retraction to permit adequate compression of spring 102' and relative movement if bolt 52' is stuck in its keeper. When the crosshead 174 reaches its extreme bolt-retraction position, switch arm 184 is operated to actuate switch 116' to the opposite position. Thereafter, when switch is moved to complete the boltextension circuit 112, the motor 94' is again energized to continue the rotation of disk 178 another half-cycle, moving pull rod 100", which relieves. the compression of spring 102' and permits bolt 50' to be extended by bias springs 52'. When crosshead 174 completes its movement to a position illustrated in full lines in FIG. 5, switch arm 182 is actuated to operate switch 116 to the opposite position, and the circuit is in condition to start the next cycle of bolt-retraction and extension.

The balance spring operates in a fashion similar to the balance spring 160 described above; it tends to balance the load on motor 94 during the two half-cycles of operation for bolt retraction .and extension, respectively, and it reduces the load on the motor during normal operation.

In FIG. 6 another modified form of the invention is illustrated; parts corresponding to those previously de scribed are referenced by similar numerals with the addition of a double-prime Mounted on a side wall 22" of the lock housing is a conventional tubular type spring latch (similar to that shown in FIG. 1); the latch includes a tube 46" secured to the mounting plate 48', a latch bolt 50" that is slidable through the plate 48" and Within the tube 46" and that is normally biased by a spring 52" towards the extended or locked position into the keeper commonly associated with such a bolt. The spring 52" bears between a shoulder on the bolt and the opposite inner wall of the tube 46". At its inner end, latch bolt 50" includes a rectangular shank 60" and head 62". A latch bolt actuator 64" is formed as a fiat member fixed to mounting plate 28" and having

upstanding walls

200 and 202 at each end thereof as well as an upstanding guide member or intermediate wall 204. The bolt shank 60" is slidably received within a rectangular slot in the wall 200, and its head 62" is retained thereby. The

walls

202 and 204 have bearing openings that slidably and rotatably support the shaft ends of an endless-worm adjustment screw 206. The endless-worm 206 has an intermediate portion that is formed with transverse left-hand and right-hand helical grooves that operate a follower arm 100 in the form of a rectangular member bearing against the flat plate of actuator 64" so as to be nonrotatable. Arm 100" has therein a rotatable member 210 with a groove-following blade 212 formed at the bottom thereof which engages in the helical grooves of endless worm 206. This mechanism is a well known device for providing reciprocating movement of the follower arm 100 back and forth along the worm as the worm shaft 206 rotates in but a single directioneln a commonly formed construction of this mechanism, the grooves at their ends are arranged to rotate the follower blade 210 a partial turn; thus, as it reaches the end of the helical groove in one direction it engages the helical groove in the other direction and thereby reverses the direction of translation of the entire follower member 208.

Bearing between follower arm 100" and wall 202 is a compression spring 102, which serves as a coupling between the arm 100" and bolt actuator 64". That is, as follower arm 100 is moved to the right (as viewed in FIG. 6), coupling spring 102' tends to be compressed and to move bolt actuator 64 to the right to retract the bolt 50"; as follower arm 100" is moved to the left, coupling spring 102" tends to be relieved to permit bolt actuator 64 and bolt 50" to be moved to the left under the action of bolt spring 52".

An extension arm 212 secured to follower arm 100", reciprocates therewith, and is biased to the right by extension spring 160" connected between arm 212 and a fixed post 162". Spring 160" serves to oppose somewhat the bias of bolt spring 52' and to balance the load on motor 224. Extension arm 212 is also used to actuate a toggle switch 116", as the follower 100" is moved to its extreme positions, by engagement with

arms

182 and 184" attached to the switch 116" in a manner similar to that described above. An extension 214 of a rear wall 202 is engaged by a cam 40", which is secured to the rotatable plug 34" of a continuous wafer lock in a manner similar to that described above with respect to FIG. 1; thereby, a mechanical key can be used to operate the lock and rotate the cam 40" against the extension wall 214 and move the bolt actuator 64" to the right for bolt retraction.

The endless worm shaft 206 is guided in the

walls

204 and 202 and is mounted in a fixed thrust bearing 216 and secured from reciprocation by appropirate shaft collars on either side of the thrust bearing. The shaft is connected via a universal coupling 218 to the output shaft 220 of a gear train 222 and motor 224. The motor 224 may be any suitable form of single-direction motor, such as an AC motor. The universal 218 assures appropriate parallel alignment of the worm shaft 206 and drive shaft 220.

In the position illustrated in FIG. 6, the bolt 50" is in the extended position for interlocking with a keeper. It is biased to this position by bolt spring 52", the balance spring 160" is extended, being weaker than the bolt spring 52", and the coupling spring 102 is in its normal, substantially uncompressed condition. When motor 224 is energized by operation of switch 110 (using the circuit of FIG. 4 with a suitable A-C or power supply), shaft 206 is rotated in the direction of the arrow to drive the endless worm portion thereof as a right-hand screw, which moves the follower arm 100" to the right (assisted by balance spring 160") to compress coupling spring 102 so as to overcome the bias of spring 52" and retract the bolt 50". When the bolt 50" is fully retracted, the follower arm 100 reaches the end of the right-hand helical groove of the worm 206, and the extension arm 212 operates the toggle switch to de-energize the motor 224, which stops substantially instantaneously due to the load thereon; the groove follower blade 210 is rotated and aligned with the left-hand groove to be ready to start on the return path upon re-energization of the motor 224. Upon operation of switch in the opposite direction, motor 224 is energized again and rotates endles worm shaft 206 in the same direction to drive the follower arm 100" along the left-hand groove back to the position illustrated in FIG. 6 to operate the switch 116" and stop the motor 224. The movement of follower arm 100" to the left, is transmitted by coupling spring 102" and bolt actuator 64" to permit bolt extension under the action of bias spring 52"; at the same time balance spring is extended to the condition illustrated.

In the embodiment of FIG. 6, a DC motor with the opposite polarities of power supply shown in FIG. 4 may be utilized; in which case, the endless worm 206 may be replaced by a conventional worm gear or adjustment screw engaging in a threaded follower arm of conventional form, and opposite rotations of such a worm gear produces the desired reciprocation of the follower arm in forward and reverse directions. Thus, in each of the above-described embodiments of the invention, a reversible electromechanical motor device is provided in which a motor arm is coupled by means of a spring to an actuator for a springbiased bolt, and reversible operation of the motor arm in opposite directions produces the desired retraction and extension of the bolt. This invention is not limited to any particular type reversible or reciprocating motor device; forex ample, a solenoid or an electrical linear actuator with an appropriate mechanical drive may be used as the electric motor which provides reversible, reciprocating movement of a motor arm (such as the

arm

100, 100" or 100") for bolt retraction and extension, the motor and mechanical drive being such as to maintain the motor arm in its extreme positions when the motor is not energized. With an appropriate mechanical drive, motor and size and .weight of the various parts, it is not necessary to provide for braking of the motor or indexing of the motor arm in its extreme positions of travel. However, if necessary due to particular requirements (such as for large or extra heavy construction), dynamic braking of the motor or a similar expedient may be employed.

For greater security, a tubular dead latch mechanism may be used in place of that of spring bolt 50"; such a dead latch mechanism operates as a spring bolt in the manner described, but, once engaged in its keeper, the dead latch cannot be retracted by forces applied to the outer end of the bolt. The free movement needed for the bolt of such a dead latch is provided by the relative sliding movement permitted between the bolt shank 60 (60") and bolt actuator 64 (64"). Moreover, this invention may be used for electrical control of the operation of a releasable keeper instead of the bolt of a lock, and such a keeper may be extended into engagement with the bolt and retracted out of engagement in a manner similar to that described above.

Thus, in each form of this invention, no standby power is required to maintain the lock in either a locked or an unlocked condition; that is, with the bolt extended or retracted. The mechanism (e.g., worm and pinion or scotch yoke) coupling the electric motor to the

motor arm

100, 100' or 100" has a mechanical advantage going from the motor to the motor arm and, therefore, is of such a nature as to 'be moved only by motor power and to remain unaffected by forces applied from the bolt end of the mechanism (e.g., by the energized coupling spring when the bolt is not free for retraction). Where binding of the bolt in the keeper occurs (due to common faults such as sagging of the door hinges or Warping or bad fit of the door), the electric motor is not overloaded in attempting to retract the bolt; instead, the motor operates only for the time necessary to store in the coupling spring the energy required for bolt retraction. This energy continues to be stored until the bolt is freed, since the motor arm is retained in position by its drive mechanism. When the door is subsequently manipulated, the bolt is ultimately freed, and the coupling spring retracts it to complete unlocking of the door. Similarly, the motor action in the reverse direction (where the bolt is blocked from extension into the keeper) is for the short time needed to transfer the energy for bolt extension and to make it available in the bolt spring, where it is stored until the door is manipulated to permit extension of the bolt. Thus, in neither case is there any danger of overloading the motor such as may damage The energization of the motor is for but a short period of time corresponding to that required to actuate the

coupling spring

102, 102' or 102 and to store the energy therein for bolt retraction, or corresponding to that required to actuate the balance spring for bolt extension. In the above described embodiments, the switch 116, 1.16 or 116" detects the appropriate movements of the

motor arms

102, 102' or 102 and cuts off the motor when the required motor arm movement is completed. Thereby, an accurate determination is made of when to cut off the motor. The switch 116 may take the various forms noted above and equivalent forms such as commutator brushes and the like. Alternatively, the switch 116 may be operated indirectly; for example, the switch 110 may also be connected to known timing circuits or other known timing devices; and the operation of switch 110 to energize the motor via circuit 112 or 1.14 may also be effective tooperate an associated timing circuit or device that actuates switch 116 to the opposite position after a certain time period that is suflicient for the motor to move the motor arm to the proper extreme positions.

Each form of the invention provides a slip-joint or movable connection between the motor arm and the bolt actuator, by way of, for example, the connection of the coupling spring; thereby, together with an appropriate mechanical lock and operator for the bolt actuator, mechanical override of the electrical control is provided for bolt retraction. Moreover, a double-security control of the bolt is made available by means of a manually-operated switch 152 that must be closed in addition to operation of switch 110 to energize the motor and retract the bolt. Thus, this switch 152 is effective only during conditions or time periods established by the operation of switch 110. This switch 152 may be any desirable :form of key-operated device or it may be actuated by a combination push-button switching device. The security requirements for the operation of switch 152 may be of a lesser character since it is only effective during limited times.

The invention is not limited to any particular form of electric motor; rotary or linear motors may be used, either A.-C. or D.-C. In the case of rotary motors, the reversing action of the motor arm or bolt actuator can be supplied by reverse rotation of the motor itself or its associated mechanical drive.

By means of a

balance spring

160, 160' or 160", the motor loading is substantially the same when operating in either the bolt-retraction or extension portion of the cycle. In addition, this spring serves to reduce the peak loading on the motor during normal operation; this reduction of loading comes about as a consequence of storing energy in the balance spring during the bolt-extension half-cycle (when both the coupling spring and bolt spring are aiding the motor drive), and using the stored energy for bolt retraction (when both the coupling and bolt springs are opposing the motor drive). The energy stored in the balance spring may come entirely from the motor during the boltcxtension half-cycle, or it may come at least in part from the bolt and coupling springs as they return excess energy to the system. It is preferred that the balance spring serve to balance approximately the load on the motor for each of the different half-cycles during normal operation; however, this relationship may vary with the lock desi n, and the balance spring may be chosen to provide a somewhat greater (or lesser) load on the motor during the bolttion and arrangement of parts may be made without departing from the spirit of the invention and the scope of the appended claims.

What is claimed is:

1. An electromechanical lock mechanism for interlocking a bolt element and keeper element of a closure, said mechanism comprising:

a movable one of said interlocking elements, including resilient means for biasing said movable element in a direction to interlock with the other of said elements; means for guiding the extending and retracting movements of said movable interlocking element into and out of interlocking relation with said other element;

an electric motor device, including means for controlling the supply of electric power to said device;

and means for coupling said motor device to said movable -interlocking element for initiating said out-oflocking movements, said coupling means including resilient means for storing energy supplied by said motor device and in an amount sufficient to effectuate said out-of-locking movement and for transmitting said energy to said movable element in a direction to effectuate said out-of-locking movement, and means between said motor device and said resilient coupling means for maintaining said resilient coupling means in an energy-storing condition when said motor device is de-energized and after having been placed in an energy-storing condition by said motor device, so that upon operation of said motor device for said out-of-locking movement said resilient means receives and retains the energy therefor when said movable interlocking element is restrained from out-of-locking movement;

said power controlling means including switch means for energizing said electric motor device to supply sufficient energy to said resilient means to move said movable element out of said interlocking relation and for thereafter terminating the energization of said device.

2. An electromechanical lock mechanism as set forth in claim 1 wherein said switch means includes means for energizing said motor device to initiate movement of said movable element into said interlocking relation and thereafter terminating the energization of said device.

3. An electromechanical lock mechanism as set forth in claim 2 wherein said coupling means includes additional resilient means energized at the time of initiation of the movement of said movable element into said interlocking relation and adapted for storing energy and for thereafter supplying said stored energy to said movable element to assist in said out-of-locking movement of said movable element.

4. An electromechanical lock mechanism as recited in claim 1 wherein said means for controlling the supply of power to said mot-or device includes a timing device having first electrical switch means and means for operating said switch means during certain time periods, and additional manually operable switch means effective to initiate the supply of power to said motor device for out-of-locking movement of said movable element only during time periods of operation of said'first switch means.

5. An electromechanical lock mechanism as recited in claim 4 wherein said manually operated switch means includes a switch, and a mechanical key-operated device for said switch.

6. An electromechanical lock mechanism as recited in claim 1, and further comprising a mechanical key-operated device including means for moving said movable element out of locking relation; said coupling means including means for accommodating said out-of-locking movement initiated by said key-operated device without interference from said resilient means and for transmitting the stored energy from said resilient means to said movable element to effectuate an out-of-locking movement thereof.

7. An electromechanical lock mechanism as set forth in claim 1 wherein said means for maintaining the energy storing condition of said resilient coupling means includes a mechanism having a mechanical advantage connected from said motor device to said resilient means whereby said de-energized motor device is substantially unaffected by forces from said resilient means.

8. An electromechanical lock mechanism as set forth in claim 1 wherein said resilient means includes spring means having a displacement corresponding to the displacement of said movable element from interlocking to out-of-locking relation, said motor device being coupled to said spring mean-s to produce said displacement thereof when supplying said energy for storage thereby, said spring means being coupled to said movable element to produce said displacement thereof when supplying said stored energy thereto.

9. An electromechanical lock mechanism for interlocking a bolt element and keeper element of a closure, said mechanism comprising:

a movable one of said interlocking elements;

means for guiding the extending and retracting movements of said movable element into and out of interlocking relation with said other element;

an electric motor device coupled to said movable element;

and means for controlling the supply of electric power to said device to effectuate interlocking and out-oflocking movements of said movable element; said controlling means including a control device having first electrical switch means and means for operating said first switch means in one way at certain times to initiate the supply of power to said motor device for interlocking movement of said movable element and in another way at certain other times, and additional manually operable switch means for initiating the supply of power to said motor device for out-of-locking movement of said movable element only during time periods of operation of said first switch means in said other way.

10. An electromechanical lock mechanism as recited in claim 9 wherein said manually operated switch means includes a switch, and a key-operated device for said switch; and further comprising a mechanical key-operated device for moving said movable element out of locking relation during time periods of operation of said first switch means in said one way.

References Cited UNITED STATES PATENTS 2,070,803 2/1937 Oblak 292-144 2,716,567 8/ 1955 Turcott 292-144 2,763,797 9/1956 Dean 318-475 X 2,789,426 4/1957 Hollins -272 X 3,234,766 2/1966 OBrien 70-271 3,242,708 3/ 1966 Sanchez 70-277 BOBBY R. GAY, Primary Examiner.

Claims

1. AN ELECTROMECHANICAL LOCK MECHANISM FOR INTERLOCKING A BOLT ELEMENT AND KEEPER ELEMENT OF A CLOSURE, SAID MECHANISM COMPRISING: A MOVABLE ONE OF SAID INTERLOCKING ELEMENTS, INCLUDING RESILIENT MEANS FOR BIASING SAID MOVABLE ELEMENT IN A DIRECTION TO INTERLOCK WITH THE OTHER OF SAID ELEMENTS; MEANS FOR GUIDING THE EXTENDING AND RETRACTING MOVEMENTS OF SAID MOVABLE INTERLOCKING ELEMENT INTO AND OUT OF INTERLOCKING RELATION WITH SAID OTHER ELEMENT; AN ELECTRIC MOTOR DEVICE, INCLUDING MEANS FOR CONTROLLING THE SUPPLY OF ELECTRIC POWER TO SAID DEVICE; AND MEANS FOR COUPLING SAID MOTOR DEVICE TO SAID MOVABLE INTERLOCKING ELEMENT FOR INITIATING SAID OUT-OFLOCKING MOVEMENTS, SAID COUPLING MEANS INCLUDING RESILIENT MEANS FOR STORING ENERGY SUPPLIED BY SAID MOTOR DEVICE AND IN AN AMOUNT SUFFICIENT TO EFFECTUATE SAID OUT-OF-LOCKING MOVEMENT AND FOR TRANSMITTING SAID ENERGY TO SAID MOVABLE ELEMENT IN A DIRECTION TO EFFECTUATE SAID OUT-OF-LOCKING MOVEMENT, AND MEANS BETWEEN SAID MOTOR DEVICE AND SAID RESILIENT COUPLING MEANS FOR MAINTAINING SAID RESILIENT COUPLING MEANS IN AN ENERGY-STORING CONDITION WHEN SAID MOTOR DEVICE IS DE-ENERGIZED AND AFTER HAVING BEEN PLACED IN AN ENERGY-STORING CONDITION BY SAID MOTOR DEVICE, SO THAT UPON OPERATION OF SAID MOTOR DEVICE FOR SAID OUT-OF-LOCKING MOVEMENT SAID RESILIENT MEANS RECEIVES AND RETAINS THE ENERGY THEREFOR WHEN SAID MOVABLE INTERLOCK ELEMENT IS RESTRAINED FROM OUT-OF-LOCKING MOVEMENT; SAID POWER CONTROLLING MEANS INCLUDING SWITCH MEANS FOR ENERGIZING SAID ELECTRIC MOTOR DEVICE TO SUPPLY SUFFICIENT ENERGY TO SAID RESILINET MEANS TO MOVE SAID MOVABLE ELEMENT OUT OF SAID INTERLOCKING RELATION AND FOR THEREAFTER TERMINATING THE ENERGIZATION OF SAID DEVICE.