US3801755A - Key cylinder and electrical switch - Google Patents

Abstract

A key cylinder housing has an upper pin therein. A cylinder plug is rotatable in the housing and contains an adjacent pin which may be a master pin or a lower pin arranged to align with the upper pin in one rotated position of the plug in the housing. A key inserted in a keyway in the plug displaces the adjacent pin so that the upper and adjacent pins abut at the rotary surfaces of the plug and the cylinder. The plug can then be key rotated in the cylinder, thus moving the abutting pins out of alignment. The plug and the upper pin are electrically conducting while the housing and the adjacent pin are electrically insulating. An electric circuit is completed through the upper pin and the plug when the plug is rotated in order to control an external mechanism in accordance with the operation of the key.

Description

United States Patent 1 [111 3,801,755 Schlage Apr. 2, 1974 KEY CYLINDER AND ELECTRICAL Primary Examiner-Herman J. Hohauser SWITCH Attorney, Agent, or Firm-Lothrop & West [75] Inventor: Ernest L. Schlage, Burlingame,

Calif. [5 7] ABSTRACT ASSigIleeI schlage Lock p y, San A key cylinder housing has an upper pin therein. A Franclsco, Califcylinder plug is rotatable in the housing and contains [22] Filed, May 3 1973 an adjacent pin which may be a master pin or a lower pin arranged to align with the upper pin in one rotated [21] Appl. No.: 356,707 position of the plug in the housing. A key inserted in a keyway in the plug displaces the adjacent pin so that 52 US. Cl. 2 44 the upper and adjacent pins abut at the rotary surfaces E InL CL on 231 of the plug and the cylinder. The plug can then be key [58] Field l R 16 C rotated in the cylinder, thus moving the abutting pins 260/5 out of alignment. The plug and the upper pin are electrically conducting while the housing and the adjacent [56] References Cited pin are electrically insulating. :An electric circuit is completed through the upper pm and the plug when UNITED STATES PATENTS the plug is rotated in order to control an external 3,742,161 6/1973 Lipschutz 200/44 hani in a cordance with the operation of the key.

7 Claims, 9 Drawing Figures I l I I I 2 y 1| I l i I l n '1 1| l 1' ll I I 8 a l 1 1 37 I 25 PATENTEUAPR 2 I974 sum 1 or 3 FIG 1 Q E /m n PAT'ENTEUAPR. 21974 13,801 755 SHEET 2 BF 3 II III PM ENIED APR 2 I974 SHEET 3 BF 3 KEY CYLINDER AND ELECTRICAL SWITCH In many instances it is desirable to have a key controlled operation conducted electrically. There are available switch mechanisms having key controls for that purpose. Most of these provide a standard key mechanism such as a pin tumbler lock and connect to the lock an actuating mechanism such as a cam which controls external switches. Mechanisms of this kind are generally satisfactory for many installations, but it is an object of this invention to provide a substantial improvement thereover.

Another object of the invention is to provide a key cylinder and electrical switch in which electrical circuitry is controlled within the key cylinder mechanism itself.

A further object of the invention is to provide a relatively compact, simple, key controlled cylinder and electrical switch.

A further object of the invention is to provide a key cylinder and electrical switch in which the key cylinder conforms generally to the construction of standard key cylinders while having an additional, electrical function.

A further object of the invention is to provide a key cylinder and electrical switch that occupies substantially no more space than a standard key cylinder unit.

Other objects, together with the foregoing, are attained in the embodiments of the invention described in the accompanying description and illustrated in the accompanying drawings, in which:

FIG. I is a partly representational and partly diagrammatic showing of a key cylinder constructed pursuant to the invention and incorporated in electrical circuitry;

FIG. 2 is a partial table showing a relationship of key bitting with the control of connected instrumentalities;

FIG. 3 is a cross-section on an axial, vertical plane through a typical key cylinder constructed pursuant to the invention, portions being broken away to reduce the size of the figure;

FIG. 4 is an exploded view showing, inisometric projection, parts of a key cylinder pursuant to the inventron;

FIG. 5 is a diagram somewhat similar to FIG. I and showing a different environment for the key cylinder of the invention;

FIG. 6 is a view comparable to FIG. 1 and showing a still further modification in the environment;

FIG. 7 is a view comparable to FIG. 1 and showing an additional variation in the environment;

FIG. 8 is a view comparable to FIG. 1 and showing an additional environmental alteration; and

FIG. 9 is a view comparable to FIG. 1 and showing different electrical circuitry controlled by the key cylinder of the invention.

In one form of the invention there is preferably provided, as shown especially in FIGS. 3 and 4, a key cylinder mechanism including a housing 6 or body having a configuration conforming generally to that of standard pin tumbler cylinder housings. In this instance, the housing is preferably formed of electric insulating material, such as a non-conducting plastic, rather than being formed of metal, as is customary. The housing 6 has a generally circular-cylindrical portion 7 substantially symmetrical about a rotational axis 8. Extending radially from the portion 7 is a rib 9 or wing preferably formed integrally with the body 6.

The body is provided with a through bore 11 symmetrical about the axis 8 and designed to receive a circularcylindrical plug 12 generally of standard configuration and conveniently fabricated of metal, as usual. The plug has an outstanding flange 13 at one end designed to abut against the end face of the body 6 and has threads 14 and the other end to receive a securing cap 16. This is screwed onto the plug until it abuts the other end of the body 6 with adequate clearance for rotation but so as to confine the plug in the housing or body against substantial axial movement.

The plug 12 is provided with a keyway 18 extending substantially therethrough and preferably having an irregular cross-sectional configuration, as is customary. Formed in the plug and intersecting the keyway 18 are several lower chambers 21, 22, 23, 24 and 25, for example, although any number of lower chambers may be provided. Each of the lower chambers is arranged with its own axis extending generally normal to the axis 8. The lower chambers are usually arranged in a single, axial plane, although they can be arranged in different planes. Each of the lower chambers intersects the keyway 18 and breaks through the outer, circularcylindrical surface of the plug 12. Disposed in each one or in each of several of the lower chambers 21, 22, 23, 24 and 25 may be a pin column inclusive of several pins. Each column includes a lower pin 27 most often made of metal. Although the lower pins may vary in length, they are all designated 27 herein. The lower pins 27 fit freely enough in the chambers so as to be easily movable in a radial direction.

In a related fashion the cylinder body 6 likewise has formed therein a number of upper pin chambers 28, 29,

30, 31 and 32 arranged so that in one rotated position of the plug 12 in the body 6, the various upper and lower chambers for the pins are in alignment with their opposites an in effect form continuations thereof. Disposed within each of the upper chambers, if desired, is one of a number of upper pins 34 of the same length or of different lengths and usually made of metal.

The pin arrangement is a usual one with the lower pins 27 and the upper pins 34 included in columns. If the upper and lower pins directly abut in one position of the plug in the body and if the pin lengths are so chosen that their abutting surfaces substantially coincide in each column with the rotary surfaces of the plug and the body, the plug can be rotated. Otherwise, one or more pins bridge the rotary surfaces and block plug rotation. The rotary surfaces are arcuate or circularcylindrical while the pin abutting surfaces are often flat, although they may be beveled or rounded or pointed. Thus, the abutting surfaces and the rotary surfaces may not precisely coincide, but the upper pins, at least, can cam or shift slightly for acceptable performance.

Particularly in accordance with the invention there is an arrangement to provide anelectrically insulating surface or body adapted to abut the lower end of at least one of the upper pins. This can be done by making the mating lower pin in the column of insulating material. It is preferred, in most cases, to introduce in at least one column an intermediate or master pin 37 made of insulating material and disposed between the upper pin 34 and the lower pin 28 so as to afford two column positions coincident with the rotary surfaces. The lower pin and the master pin are referred to as adjacent pins for one or the other is adapted to abut the neighboring upper pin.

The pin lengths are chosen in such a way that when a proper key 38 (either an ordinary key or a master key) is present in the cylinder plug keyway, the various lower pins 27, intermediate or master pins 37 and upper pins 34 are positioned with one of the pairs of mating end surfaces in each column substantially coincident with the adjacent rotary surfaces of the plug 12 and the housing 6. The key 38 and the plug 12 can then be rotated about the axis 8 to produce any desired mechanical actuation in the customary fashion. If an improper key is tried in the keyway 18, the key notches leave at least one of the pins, such as 27, 34 or 37, in a position straddling the rotary surfaces of the plug and housing preventing plug rotation.

Particularly in accordance with this invention, one or more of the upper pins 34is connected in an electric circuit through the customary metallic spring 41 used to urge the pins toward the plug or keyway. To that end each of the springs 41 not only abuts the related upper pin 34 but also abuts one of a group of metallic disks 42 each lodged in one end of the related upper chamber, such as 28, for example. Each disk has an individual one of a group of conductors 43 connected to it and passing through the housing 6. Each conductor is connected by one of a number of leads 44, 45, 46, 47 and 48 to a representative work device; for example, to its respective one of a group of indicator lights 49. These are joined by appropriate leads at junctions A, B, C, D

and E to a common conductor 51 connected to a battery 52 or other suitable source of electric power.

The circuit is continued by joining the other side of the battery 52 through a lead 53 to a stationary brush 54. A lug 56 on the brush receives the lead 53 while a ring 57 abuts the metallic plug 12 and especially abuts the metallic end cap 16. A good electrical contact is made with the plug in all different rotated positions of the plug within the housing.

In the operation of the device, with or without a proper key in position and even though the metallic plug 12 is connected to the electric source 52, and even though one or more of the upper pins 34 is similarly connected to the source 52 through a work device 49, there is no completed circuit since the upper pins 34 are surrounded by insulation and are physically out of touch with the plug 12, partly by reason of the insulating adjacent pins.

When a proper key is being introduced or is in the keyway, the various columnar pins are so positioned that the abutting surfaces thereof are even with the rotating surfaces of the plug and housing. The upper pins never drop into metallic contact with the plug. There is no electrical contact. But the proper key permits turning of the plug in the housing. When such rotation begins to occur, the metallic plug then comes into physical contact with the adjacent surface of at least one of the upper pins 34. This is all that is required to complete a circuit, for example, through the one of the lamps 49 according to the particular upper pin contacting the plug. The corresponding lamp 49 is lit and affords an indication of operation of the lock plug and also affords an indication that a particular key, able to position the particular upper pin for conduction, has been utilized. If, for example, a master key has lifted the intermediate pin 37 in the same column into the upper chamber, there is no circuit completed for the intermediate pin, although in contact with the plug, is an insulator. Thus, for the same column one key indicates its use while another key, of differing notching, does not indicate its use.

If in addition to or as a substitute for one of the lamps 49 there is a different work device, such as a motor or an electric door latch, a corresponding key controlled actuation is electrically produced. This is accomplished without external switches and with all of the make and break mechanism well within the confines of the virtually standard key unit.

It is possible to arrange matters, for example, as shown in FIG. 3, so that two upper pins 34 might both contact the metallic plug 12. If so, the circuit can be rearranged and brush mechanism 54 can be dispensed with. The corresponding two leads, such as 44 and 45, can be connected to the source of power through an indicator. Dual contacts complete the circuit. It is preferred, however, to have the brush mechanism and to have each of the pins separately connected. This is for the reason that a family of keys effective to actuate the lock mechanism may then each actuate an individual one or selected ones of the conducting pins or insulating pins to contact the rotated plug.

By various arrangements of the insulating and conducting pins, various different results can be produced. As shown in the table of FIG. 2, the possibilities of differently combinated locks and differently notched keys are illustrated for a situation in which there are five different pin columns with the possibility in each column of electrical contact or no electrical contact. Contact and no contact are represented respectively by the digits 1 and 0. The number of different possibilities in this instance is 32, whereas with a different number of pin columns; for example, six, the number of possibilities is 64.- By observing the lamps 49, it is easy to detect which of say 31 (or 63) different keys has actuated the lock, as one key lights no lamp.

As an example of other uses, the mechanism, having five columns as shown in FIG. 3, is incorporated in appropriate electrical circuits as illustratd in FIG. 5. The circuitry includes the leads indicated before with their customary power source extending to a logic unit 61 of well known sort which distributes an impulse either to a solenoid bolt actuator 62, as an example of a work piece, or to an alarm device 63. The impulse route depends upon whether the key utilized has been coded as proper or improper. That is to say, an authorized key is effective to energize the logic circuitry 61 so that the ultimate impulse goes to the solenoid mechanism 62 and thus retracts a door bolt, for example, whereas an improper key energizes the logic circuitry 61 to send the corresponding signal to the alarm mechanism 63 and so afford a visual or audible indication that an improper entry has been attempted.

In a somewhat comparable fashion, the circuitry shown in FIG. 6 is effective upon a logic unit 64 to operate a disabling solenoid 66, for example, to interrupt the mechanical connection 67 between the lock unit and a door bolt 68 to which the lock drive 67 is connected. In the operation of this mechanism a proper key operates the bolt 68 mechanically to withdraw it in the usual way but in the event an improper key is utilized, the electrical connections affect the logic unit 64 so as to activate the disabling solenoid 66 and thus disconnect the mechanical drive 67 from the bolt 68 and prevent withdrawal of the bolt by the improper key.

In a related fashion, as shown in FIG. 7, a mechanical connection 71 between the key mechanism and a door lock 72 is standard but the electrical circuitry is effective upon a responsive device 73 to actuate a time device 74 in the nature of a recorder or the like. Each time the lock is operated by a key a record is made of the time of the operation and preferably by which key.

In a somewhat simpler system, as shown in FIG. 8, the circuitry from the key mechanism is effective to operate an alarm 76 each time the lock 77 is actuated under any circumstances by any of the keys of the group that produce contact. The warning indicates that the lock mechanism 77 has been put into unlocked condition or into locked condition, as preferred, by an unauthorized key.

In FIG. 9 there is shown a more elaborate system. In this arrangement each of the leads 81, 82, 83, 84 and 85 from the lock mechanism extends to its own one of a group of relays 87, 88, 89, 90 and 91 having a common conductor 93 extending to one side of a source 94 of electromotive force, the other side of which is joined by a lead 97 to the brush 54. Upon rotation of the key individual circuits may be completed through the individual relays.

Each relay is effective upon one of a group of single pole, double-throw switches 98, 99, 101, 102 and 103. The switches are joined in pairs by conductors 106 and 107 and a conductor 108 is joined to the conductor 93. With this arrangement when the individual relays are energized they serve to transfer the double-throw switches 98, 99, 101, 102 and 103 from the position shown into an opposite position. In order for this motion to have the desired effect, each switch is connected at both contacts by conductors 1 l l and 112, for example, to the respective one of a group of oppositely disposed single pole, double- throw switches 113, 114, 115, 116 and 117. These are connected in pairs in that the switches 114 and 115 are joined by a conductor 118, while the switches 116 and 117 are joined by a conductor 119. The switch 113 is joined by a conductor 121 through a latch bolt operating solenoid 122 to the battery 94. 7

With this mechanism the user can set one or more of the switches 113, 1 14, 115, 116 and 117 in either ofthe two extreme positions according to any code that he selects. Then, the individual relays 87, 88, 89, 90 and 91, when effective to throw the switches 98, 99, 101, 102, and 103, either produce an open circuit situation or a closed circuit situation. A proper key in energizing selected ones of the leads 81, 82, 83, 84 and 85 can complete a circuit through the solenoid 122 to actuate the lock. An improper key produces only an open circuit and the solenoid 122 is not then energized. This affords the lock owner easy changes in the five digit combination at any time in accordance with a simple, manual routine.

In all of the forms of the invention the characteristic of the pin tumbler lock unit is to have an open circuit change to a closed circuit within the lock mechanism by rotation of the lock plug.

While in the foregoing description and in the drawings it is the lock housing that is insulating, it is equally possible to make the plug of insulating material and the housing of conducting material and to arrange that the lower pins, such as 27, in an insulating plug 12, contact a conducting housing. In both instances a virtually standard lock mechanism by the inclusion of certain insulators or insulating pins is made into a device for appropriately controlling an electrical circuit.

What is claimed is:

1. A key cylinder and electrical switch comprising a cylinder body of electrically insulating material and formed with a passage therein symmetrical about an axis, a cylinder plug of electrically conducting material disposed in said passage and rotatable about said axis, means defining an upper pin chamber in said body and a lower pin chamber in said plug adapted to align in one rotated position of said plug in said body, an upper pin of electrically conducting material in said upper pin chamber, means for urging said upper pin towards said plug, means in one of said pin chambers and effective in said one position for separating said upper pin from said plug, a source of electrical power, and means for connecting said plug through said source to said upper pm.

2. A device as in claim 1 in which said separating means includes a pin of electrically insulating material.

3. A device as in claim 2 including a lower pin in said lower chamber and in which said pin of electrically insulating material is a master pin disposed between said upper pin and said lowerpin.

4. A device as in claim 1 in which said connecting means includes a brush abutting said plug.

5'. A device as in claim 1 in which said plug includes a keyway open to said lower pin chamber and adapted to receive a key engageable with said lower pin.

6. A key cylinder and electrical switch comprising a cylinder body formed with a passage therein symmetrical about a mainaxis and having an upper pin chamber therein normal to said main axis, a cylinder plug rotatable in said passage about said main axis and formed with a keyway extending axially therein and with a lower pin chamber therein opening to said keyway and adapted in one rotated position of said plug in said body to align with said upper pin chamber, an upper pin in said upper pin chamber, a lower pin in said lower pin chamber, at least one of said pins being of electrically conducting material and one of said cylinder body and said cylinder plug being of electrically insulating material and containing said electrically conducting pin and the other of said cylinder body and said cylinder plug being of electrically conducting material, an electrical insulator disposed between said upper pin and said lower pin in said one rotated position, a source of electrical power, and means for connecting said source to said other of said cylinder body and said cylinder plug and to said electrically conducting pin.

7. A key cylinder and electrical switch comprising a cylinder housing, an upper pin in said housing, a cylinder plug rotatable in said housing, a lower pin in said plug adapted to be positioned out of and in alignment with said upper pin, a key receivable in said plug for displacing said pins to abut at the rotary surfaces of said plug and said cylinder and for rotating said plug to move said pins into and out of alignment, an electric circuit, and means including said upper pin and said plug for opening and closing said circuit by said rotation.

Claims (7)

1. A key cylinder and electrical switch comprising a cylinder body of electrically insulating material and formed with a passage therein symmetrical about an axis, a cylinder plug of electrically conducting material disposed in said passage and rotatable about said axis, means defining an upper pin chamber in said body and a lower pin chamber in said plug adapted to align in one rotated position of said plug in said body, an upper pin of electrically conducting material in said upper pin chamber, means for urging said upper pin towards said plug, means in one of said pin chambers and effective in said one position for separating said upper pin from said plug, a source of electrical power, and means for connecting said plug through said source to said upper pin.

2. A device as in claim 1 in which said separating means includes a pin of electrically insulating material.

3. A device as in claim 2 including a lower pin in said lower chamber and in which said pin of electrically insulating material is a master pin disposed between said upper pin and said lower pin.

4. A device as in claim 1 in which said connecting means includes a brush abutting said plug.

5. A device as in claim 1 in which said plug includes a keyway open to said lower pin chamber and adapted to receive a key engageable with said lower pin.

6. A key cylinder and electrical switch comprising a cylinder body formed with a paSsage therein symmetrical about a main axis and having an upper pin chamber therein normal to said main axis, a cylinder plug rotatable in said passage about said main axis and formed with a keyway extending axially therein and with a lower pin chamber therein opening to said keyway and adapted in one rotated position of said plug in said body to align with said upper pin chamber, an upper pin in said upper pin chamber, a lower pin in said lower pin chamber, at least one of said pins being of electrically conducting material and one of said cylinder body and said cylinder plug being of electrically insulating material and containing said electrically conducting pin and the other of said cylinder body and said cylinder plug being of electrically conducting material, an electrical insulator disposed between said upper pin and said lower pin in said one rotated position, a source of electrical power, and means for connecting said source to said other of said cylinder body and said cylinder plug and to said electrically conducting pin.

7. A key cylinder and electrical switch comprising a cylinder housing, an upper pin in said housing, a cylinder plug rotatable in said housing, a lower pin in said plug adapted to be positioned out of and in alignment with said upper pin, a key receivable in said plug for displacing said pins to abut at the rotary surfaces of said plug and said cylinder and for rotating said plug to move said pins into and out of alignment, an electric circuit, and means including said upper pin and said plug for opening and closing said circuit by said rotation.

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