Having described the invention, what is claimed
as new and desired to be secured by Letters Patent is
1. A method of burglar proofing an opening closed by two relatively movable members, comprising the steps of:
2. A method of burglar proofing an opening closed by two relatively movable members, comprising the steps of:
3. Nonvisible lock means for interlocking two relatively movable members positioned to close an opening, said lock means comprising:
4. The lock means of claim 3 wherein said latch includes two interconnected portions which are substantially axially aligned, one latch portion being of nonferrous material and engageable with said other member for interlocking the members, and the other latch portion being of ferromagnetic material responsive to magnetic pull, said casing being tubular, and said abutment being engaged by the ferromagnetic latch portion at the end of movement of the latch to a position interlocking the members for maintaining the members locked by preventing endwise movement of the latch, said nonferrous latch portion in such position of the latch extending beyond the casing and said one member for locking engagement with said other member.
5. The lock means of claim 4 wherein said ferromagnetic and nonferrous latch portions are longitudinally spaced and interconnected by an elongated rod-like connector; and an axially movable rotor mounted on the casing for selective engagement with the connector for endwise movement of the latch in response to rotation of the rotor, access to the rotor being from only one side of said one member; whereby the latch can be optionally operated by a magnet from either side of said one member and by the rotor from said only side thereof.
6. The lock means of claim 5 wherein the rotor is mounted for rotation about an axis extending transversely of the axis of the connector and offset therefrom, and the rotor has a frusto-conical shape operative to disengage the ferromagnetic portion from the casing abutment for unlocking the members.
7. The lock means of claim 3 wherein said casing is of tubular nonferrous material and has an end substantially flush with an exterior edge of said one member, a ledge within the casing spaced inwardly of said end and defining said abutment, said latch including two interconnected portions, one latch portion being engageable with said other member for interlocking the members, and the other latch portion being magnetically responsive, said latch portions being axially aligned with the magnetically responsive portion disposed inwardly of said one latch portion, and said latch having an overall length wholly containable within the casing when said magnetically responsive latch portion rests on the ledge but causes said one latch portion to extend beyond the casing end when the magnetically responsive portion is disposed between the casing end and the abutment, magnetic pull being effective for lifting the magnetically responsive latch portion to disengage it from the abutment and move it inwardly.
BACKGROUND OF INVENTION
The present invention relates to burglar-proofing systems for securing houses and other buildings, and more particularly to a method and lock mechanism for burglar-proofing an opening closed by two relatively movable members such as a door and jamb, a pair of window sashes or a sash and its jamb, the lock mechanism featuring a hidden latch concealed from external view and operated by an external magnet instead of a key so as not to give away its location.
Obviously, if a burglar wants to gain entrance badly enough, he can break in through a door or window. However, such means of ingress attracts undesirable attention since the technique of an experienced burglar is to work quietly and quickly on door locks, some of which offer very little challenge to his lock-picking skill. Most security systems to date are based on the premise of making it tougher for the burglar to pick door locks so that he'll go on to easier pickings. Such systems variously employ key-operated locks with disc tumblers or pin-magnetic tumblers, some using a keyless lock operated electronically by push buttons. While such locks are highly effective, they are also quite expensive, and the keyholes or push buttons associated therewith signal or advertise their type and location.
SUMMARY OF INVENTION
It is therefore a primary purpose of the present invention to provide a new and improved burglar-proof security system for a house or other building.
Another object is to provide a burglar-proof security system which is of simple inexpensive construction, yet is highly effective in baffling skilled burglars and denying them entrance.
A further object is to provide a method and means for burglar-proofing a door or window opening.
Still another object is to provide a lock mechanism which is concealed and gives no external evidence of its location.
A further object is to provide a lock mechanism which is hidden within a door or the like and is operated by an external magnet so as to be devoid of a keyhole or other evidence of its type or location.
These and other objects and advantages are achieved by providing a lock mechanism embodying the principles of the present invention and featuring a movable latch hidden within a door or window sash and operated by an external magnet of predetermined strength. Preferably, the latch is in addition to a conventional door lock and dead lock which, ostensibly, appear to be the only lock means. Thus, the door remains locked, even through the door and dead locks have been unlocked or picked. The dead lock is used as a reference point for movement of the magnet along a path which moves the latch for locking and unlocking the door or window.
In its simplest form, the latch includes a ferromagnetic portion and nonferrous bolt, connected for movement together and slidable in a nonferrous tubular casing which has a ledge defining an abutment, the ferromagnetic portion moving in response to the pull of the magnet for selectively positioning the bolt wholly within the casing or extending it therefrom for locking or unlocking the door or window. In the locked position of the latch, the abutment engages the ferromagnetic portion and prevents dislodgement of the bolt. It is understood, of course, that more than one lock mechanism of the present invention can be employed with each door or window.
A significant feature of the present invention is the complete concealment of the lock mechanism when the door or window is locked and the utter lack of any visible evidence of its exact location. Should a burglar break in through a window, he cannot open the door or another window. Thus, in the case of surprise he must retreat through the broken window or break out elsewhere, which renders his departure more difficult and time-consuming, making for easier apprehension.
The present invention also provides a modified form of latch in which the ferromagnetic and nonferrous bolt portions are interconnected by a nonferrous rod-like connector engageable by a rotor for endwise movement of the latch in response to rotation of the rotor about an axis extending transversely of the axis of the connector, the rotor being axially movable and of frusto-conical shape for disengaging the ferromagnetic portion from the casing abutment to unlock the latch.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is an elevational view of a house door and jamb equipped with lock mechanisms embodying the principles of the present invention and concealingly mounted in the door.
FIG. 2 is an enlarged fragmentary elevational view of the door alone.
FIG. 3 is a fragmentary end view of the door.
FIG. 4 is a plan view, partly in section, of a magnet used for operating the lock mechanism of the present invention.
FIG. 5 is an enlarged fragmentary vertical sectional view of the door showing the lock mechanism of the present invention in its unlocked position.
FIG. 6 is a view similar to FIG. 5 but showing the lock mechanism in its locked position.
FIG. 7 is a horizontal sectional view along line 7--7 in FIG. 6.
FIG. 8 is a fragmentary elevational view of a window having sash frames to which lock mechanisms embodying the principles of the present invention are applied.
FIG. 9 is an enlarged fragmentary vertical sectional view of a door and jamb with a modified form of lock mechanism operable by a magnet or a key and shown unlocked.
FIG. 10 is a view similar to FIG. 9 but with the lock mechanism shown locked.
FIG. 11 is a horizontal sectional view of the lock mechanism in locked position and showing the key for mechanical operation thereof.
DESCRIPTION OF EMBODIMENTS
Referring to the drawings, there is shown in FIG. 1 a lock mechanism 10 embodying the principles of the present invention and concealed in a door 12 hingedly mounted for swinging relative to a jamb 14 and molding strip 16 forming part of a house or other building 18. As better seen in FIGS. 2 and 3, the door is equipped with a conventional door lock 20 operated by hand knobs 22 and having a dead lock 24 controlled from within by a finger knob 26 and from without by a key, not shown, insertable in a keyhole 28.
The present invention contemplates the provision of an additional dead lock 30 having the usual knob 32 and keyhole 34 spaced a predetermined distance from the hidden lock mechanism 10 for a purpose later appearing. Ostensibly, the door 12 appears to be locked solely by a key or keys insertable in the keyholes 28 and 34 clearly visible from without. However, the lock mechanism 10, which is hereinafter described in greater detail, is adapted to be operated by an external magnet 36 of predetermined strength.
As shown in FIG. 4, the magnet 36 is mounted in a holder 38 to which is attached a chain 40 having a key or pin 42 on the free end thereof. The holder is made of nonferrous material, such as plastic, aluminum or brass, and can be provided with a holding clip 44. The chain and key are also of nonferrous material and designed to dispose the magnet adjacent the lock mechanism as shown in FIGS. 2 and 3, the chain being of predetermined length for the purpose. Thus, with the key or pin inserted in the keyhole 34, the magnet can be swung along an arc, as shown by the arrows 46 and 48 in FIG. 2, which arc has a radius substantially equal to the predetermined distance of the lock mechanism from the dead lock 30. The keyhole 34 serves as a reference point for properly positioning the magnet relative to the lock mechanism. The knob 32 serves as a reference point on the other side of the door and is provided with a hole to receive the key or pin 42.
Inviting attention to FIGS. 5, 6 and 7, the lock mechanism 10 of the present invention includes a latch 50 in the form of a cylindrical bar having a nonferrous bolt portion 52 and a ferromagnetic portion 54 movable in response to the pull of the magnet 36, the portions being suitably interconnected for movement together. The latch is mounted for sliding movement in a tubular casing or sleeve 56 of nonferrous material having a smooth interior surface for minimizing frictional drag. The sleeve is coextensively disposed in a substantially horizontal bore 58 formed in one edge of the door 12 and has a length sufficient to contain the latch therewithin, as shown in FIG. 5. In such position of the latch, the door is unlocked provided, of course, the dead locks 20 and 30 are also unlocked. However, when the magnet 36 is moved in the direction of the arrow 46 in FIG. 2, it attracts the ferromagnetic portion 54 and pulls the latch 50 to the right. This causes the outer end of the bolt portion 52 to extend beyond the door edge and enter a strike 60 in the form of a sleeve in the jamb 14, as shown in FIGS. 6 and 7. In such position of the latch, the door 12 is locked against movement relative to the jamb 14.
To maintain the latch 50 in locked position, the sleeve 56 is formed with a ledge 62 providing a slight shoulder or abutment 64, on the order of one-sixteenth inch or so, against which the free end of the ferromagnetic portion 54 bears, as shown in FIG. 6. To move the latch from locked position, the ferromagnetic portion must first be attracted by the magnet 36 and raised for disengagement from the shoulder, after which movement of the magnet in the direction of the arrow 48 in FIG. 2 returns the latch to the unlocked position of FIG. 5.
The bolt portion 52 can be of any suitable nonferrous material such as aluminum, brass, strong plastic or plastic reinforced with metal rods or wires. The ferromagnetic portion 54 can be completely of metal or of plastic loaded with suitable particles having ferromagnetic properties.
A significant feature of the present invention is the complete absence of any indication of the location of the lock mechanism 10 when the door 12 is closed. With the lock mechanism installed as hereinbefore described, only the end thereof is visible, as shown in FIG. 3, when the door is open. But when the door is closed and locked, as shown in FIG. 7, the molding strip 16 covers a gap 66 between the door and jamb 14 and hides from without that part of the lock mechanism extending across the gap.
It is believed that the operation of the lock mechanism of the present invention is clearly apparent and is briefly summarized at this point. With the lock mechanism 10 disposed in unlocked position, as shown in FIG. 5, the door 12 is closed and the dead locks 20 and 30 are operated to lock the door. Using the keyhole 34 as a reference point, the magnet 36 is then suspended and swung in the direction of arrow 46 in FIG. 2 along an arc having a radius substantially equal to the length of the chain 40, which properly positions the magnet to move the latch 50 to locked position, as shown in FIGS. 6 and 7. The magnet is then removed and the door appears to be locked solely by locks 20 and 30, the presence of which is advertised by the keyholes 28 and 34. However, there is no visible evidence of the lock mechanism 10 and even if a burglar should unlock or pick the dead locks 20 and 30 the door still remains locked and his desire for quiet entry is denied. For additional security, another lock mechanism 10' in accordance with the present invention can be provided and operated using the keyhole 28 or any other reference point as the center for the arc of swinging of the magnet. To unlock, the magnet is properly positioned and tilted to disengage the end of the ferromagnetic portion 54 from the abutment 64 and raise it slightly above the ledge 62, after which the magnet is swung in the direction of the arrow 48 to move the latch to the unlocked position shown in FIG. 5. The same is done with the lock mechanism 10', if any. This, of course, is in addition to unlocking the dead locks. Inside, the dead locks and lock mechanisms are operated to secure the door against undesired entry.
The lock mechanism of the present invention can also be applied to the windows of a house or other building. As shown in FIG. 8, a window 70 having upper and lower sash frames 72 and 74 mounted for sliding in a jamb 76, and locked together by the usual fastener 78, can have lock mechanisms 10" concealingly installed in the sash frames for further locking the sash frames against movement relative to the jamb. The lock mechanisms 10" are similar to the lock mechanism 10 previously described and are installed by boring a horizontal hole through each of the sash frames and into the jamb and mounting the latch casing in the sash frame and the strike in the jamb. The holes in the sash frames are preferably plugged and painted over to hide the location of the lock mechanisms. As viewed in FIG. 8, leftward movement of a magnet, such as the magnet 36, along the sash frame adjacent the lock mechanism will cause locking, reverse movement unlocking. Alternatively, the magnet can be placed substantially in axial alignment with the lock mechanism to unlock the same.
For further security, the sash frames 72 and 74 are interlocked by a lock mechanism 10'". Such lock mechanism is also similar to the lock mechanism 10 and has its latch housing mounted within a bore in the sash frame 74 and its strike within a bore in the sash frame 72. The bore in the sash frame 74 is preferably capped by a removable cover 80 which can serve as a reference point for operation of the lock mechanisms 10". The lock mechanism 10'" is operated to locked position by a magnet 36, disposed over the lock mechanism and extending upwardly from the sash frame 74, and moved away from one viewing FIG. 8. Unlocking can be performed by reverse movement of the magnet or by axially aligning the magnet with the lock mechanism 10'".
FIGS. 9, 10 and 11 show a modified form of lock mechanism 90 installed in a door 92 and jamb 94 to which is secured a molding strip 96 covering a gap 98 between the door and jamb. The lock mechanism includes a latch 100 made up of a cylindrical non-ferrous bolt portion 102 and a cylindrical ferromagnetic portion 104 interconnected by a nonferrous rod-like connector member 106. The latch is slidably mounted in a latch casing 108 having a smooth interior surface to minimize friction and a ledge 110 providing a shoulder or abutment 112 against which the free end of the portion 104 lodges in the locked position of the latch, as shown in FIG. 10. In the locked position of the latch, the bolt portion 102 extends into a tubular strike 114 mounted in the jamb.
The lock mechanism 90 can be magnetically operated similarly to the lock mechanism 10. In addition, the lock mechanism 90 can be mechanically operated from within the house or building by a key 116 having pins 118 operative to rotate a rotary drive member or rotor 120 having bores 122 receiving the pins, FIG. 11. The rotor is secured to a support plate 124 suitably perforated to pass the pins and journaled for rotation in a housing 126 mounted in the door 92 so that the rotor projects through an aperture 128 in the casing 108 for rotation about an axis extending transversely of the longitudinal axis of the rod-like connector member 106 but slightly offset downwardly therefrom. The rotor is also capable of limited sliding along its rotational axis and is urged away from the member 106 under the urging of a thin spring 130.
The member 106 is adapted to be engaged by the rotor 120 for raising the ferromagnetic portion 104, to clear the abutment 112 for disengagement therefrom, and for moving the latch 100 to the unlocked position shown in FIG. 9. To this end, the rotor has a frusto-conical or tapered shape, the surfaces of the rotor and member 106 being notched or having frictional characteristics whereby rotation of the rotor drives the member.
The lock mechanism 90 is installed centrally in doors of conventional thickness, as shown in FIG. 11, and can be operated from within or without by a suitable magnet, such as the magnet 36, and from within by the magnet or the key 116. In the case of extra thick heavy doors, the lock mechanism can be installed near enough the outside surface thereof so as to be operated by the magnet on the outside, and with the key on the inside. Thus, although there is some evidence internally, there is no visible external evidence of the lock mechanism to give away its presence.
The aforedescribed locked mechanisms of the present invention form parts of a security system and method for burglar proofing a house or other building. The system contemplates use of the lock mechanisms in addition to the usual dead locks for doors and fasteners for windows for baffling and foiling burglars adept at picking conventional locks. In this connection, conventional dead locks can be provided with switches which close upon the insertion of a key, pin or pick to complete a circuit causing a floodlight to come on and surprise the burglar at his work. If this does not scare him away, he finds that after picking the dead locks the door still does not open. This is very likely to cause him to seek easier pickings. The system has a further advantage in that where a burglar gains entrance by breaking a window and crawling through, should he be surprised inside he cannot open any outside door or window and can retreat only through the broken window or break a door or other window. This is not only noisy and takes more time than easy passage through a door but also has a great element of bodily danger so that the burglar could well injure himself and be met by a police officer as he tries to leave the premise. The location of the lock mechanisms is varied to make detection thereof extremely difficult and virtually impossible.
There has thus been provided a new and improved method and means for burglar proofing a house or other premise by use of magnetically operated lock mechanisms hidden from external view which are relatively inexpensive yet operate effectively in a reliable manner to baffle burglars and deny them quiet entrance.
Although the present invention has been herein shown and described in considerable detail in what is believed to be the most practical and preferred embodiments thereof, it is to be understood that many variations thereof are possible and that the present invention is not to be limited to such details but is to be considered in its broadest aspects and accorded the full scope of the appended claims.