US3877740A

US3877740A - Tubular deadlock for securing windows and doors closed

Info

Publication number: US3877740A
Authority: US
Inventors: Bernard J Carvell; W Nelson Sandford; Robert C Ryan
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-08-29
Filing date: 1972-08-29
Publication date: 1975-04-15
Anticipated expiration: 1992-04-15
Also published as: CA992759A; JPS49125199A

Abstract

A deadlock is described which will automatically secure an opening closure, such as a sliding glass window, in its closed position whenever it is moved to such closed position. The deadlock includes a circular housing tube which is rigidly mounted adjacent the edge of an opening to be secured. A blocking tube is rotatably supported within the housing tube for movement on a cylindrical path between a retracted position at which it allows opening movement of the closure and an extended position at which it prevents such opening movement. Moreover, the lock includes an edge which is engagable by the closure when it is being closed to cause automatic movement of the blocking tube into its extended position to prevent unauthorized reopening of such closure.

Description

United States Patent Carvell et a1.

[ Apr. 15, 1975 1 TUBULAR DEADLOCK FOR SECURING WINDOWS AND DOORS CLOSED C. Michael Zimmerman, Palo Alto, Calif. a part interest Filed: Aug. 29, 1972 Appl. No.: 284,490

[73] Assignee:

U.S. Cl 292/216; 292/202 Int. Cl. E05c 3/26 Field of Search 292/78, 190, 202, 216

[5 6] References Cited UN lTED STATES PATENTS M ll/U Primary ExaminerRichard E. Moore Attorney, Agent, or FirmC. Michael Zimmerman,

Esq.

[5 7 ABSTRACT A deadlock is described which will automatically secure an opening closure, such as a sliding glass window, in its closed position whenever it is moved to such closed position. The deadlock includes a circular housing tube which is rigidly mounted adjacent the edge of an opening to be secured. A blocking tube is rotatably supported within the housing tube for movement on a cylindrical path between a retracted position at which it allows opening movement of the closure and an extended position at which it prevents such opening movement. Moreover, the lock includes an edge which is engagable by the closure when it is being closed to cause automatic movement of the blocking tube into its extended position to prevent unauthorized reopening of such closure.

12 Claims, 9 Drawing Figures PATENTED APR 1 51975 TO CLOSE.

PATENTEDAPR 1 51975 sum 3 or I? UNLOCK TUBULAR DEADLOCK FOR SECURING WINDOWS AND DOORS CLOSED BACKGROUND OF THE INVENTION The present invention relates to a deadlock for securing opening closures. such as windows and doors, in their closed position and, more particularly. to such a deadlock which provides such locking in a fail-safe and tamper-proof manner.

In the past several years, there has been a sharp rise in the number of home burglaries. In this connection.

' burglars have found that is a relatively easy matter to I glass windows include a spring-loaded latch which engages with a lip on the frame of the window when the window is closed. Typically, however. such latches are not satisfactorliy protected from unlatching from the outside. Moreover, many of such latches provide a minimum of locking engagement and are often easily forced. Other locks on both sliding windows and sliding glass doors may be circumvented simply by lifting the window or door from its frame.

Because burglars wish to avoid the noise associated with the breaking of glass for entry, the provision of satisfactory locks on sliding glass doors and windows tends to deter most burglars. For this reason, many different auxiliary locks for sliding glass windows and doors have been made available. In general, though, such locks are inconvenient to use. Most require special manipulation before they will lock the window. For example, many auxiliary locks are simply blocks of one sort or another which sit within the track of the sliding closure to prevent it from being opened. Such blocks must, of course, be placed within the track after each time the closure is opened. It is not unusual for one to forget or otherwise fail to place the block in position every time after the closure has been opened. The result is that as a practical matter, such locks are only partially effective. There are many instances in which such locks are installed, but in which the home owner or renter fails to secure them and comes home to find the home burglarized.

SUMMARY OF THE INVENTION The present invention provides a deadlock which is especially useful for providing a tamper-proof, fail-safe securance of opening closures, such as sliding glass doors and windows, in their closed position. In its basic aspects, the deadlock includes a movement blocking member which is rotatable on a generally circular cylindrical path, and carrying means for such blocking member which is rigidly mountable adjacent an edge of an opening to be secured. The mounting location is one at which when the window or door for the opening is in its closed position, the cylindrical path of the blocking member is intersected by the edge of such opening closure. The carrying means limits the motion of the blocking member to such circular cylindrical path between an extended position in which it blocks opening movement of the opening closure after it is in the closed position, and a retracted position in which it is free of opening movement of such closure. Releasable means are also provided for retaining the blocking member in its extended position blocking opening movement of the closure until such time at it is desired to open such closure from the inside of the wall having the opening.

The rotary motion of the blocking member into its extended position brings the same to a location behind the frame or other structure of the closure to prevent opening movement thereof. It will be appreciated that it is much more difficult to tamper with such a blocking lock which is shielded from the edge of the opening than more conventional catch locks provided by manufacturers of sliding glass doors and windows.

Most desirably, the blocking member includes an edge which when such blocking member is in its retracted position extends into the path of the window or door for engagement with and rotary movement of, the block member to its extended position by such closure upon the block member being moved to its closed position. With this structure, closure of a window or door will automatically cause the blocking member to assume its blocking position. Thus, the extra manipulation required by many auxiliary locks to make them operative is avoided.

The deadlock of the invention also includes releasable means which locks the blocking member into its extended position upon such rotary movement of the same on its cylindrical path from its retracted to such extended position. More particularly, coacting cam surfaces guide the blocking member in axial movement as it rotates to engage locking portions of such cams to normally prevent reverse rotation of the blocking member from its extended position. Such coacting cam locking surfaces provide securance of the blocking member in its extended position without it being spring loaded to such position. Thus, the locking action provided by the blocking member is analogous to that provided by a dead bolt lock. As is well known, such a deadlock is much more difficult to circumvent than a spring-loaded lock.

The deadlock of the invention includes many other features and advantages which are important and which will be described or will become apparent from the following more detailed description of a preferred embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS With reference to the three accompanying sheets of drawing:

FIGS. 1 and 2 are partial perspective views illustrating a preferred embodiment of the deadlock of the invention mounted in position to provide locking for a sliding glass window, FIG. 1 showing the window in its closed position with the lock operative, and FIG. 2 illustrating the window open;

FIG. 3 isan enlarged, exploded and broken view showing details of the construction of the embodiment of FIG. I of the invention;

FIGS. 4 and 5 are respectively partial, exploded views of the lower and upper ends of the deadlock of FIG. 1;

FIGS..6 and 7 are partial end views of an embodiment of the deadlock of the invention incorporating a key operated lock;

FIG. 8 is an elevation view of an embodiment of the deadlock of the invention used to lock a swinging door; and

FIG. 9 is an enlarged sectional view of the lock of FIG. 8 and its relationship to the swinging door and the jamb therefor.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is first made to FIGS. 1 and 2 for a general overall description of a preferred embodiment of the deadlock of the invention, including its operation. More particularlyg such deadlock, generally referred to by the reference numeral 11, is shown installed in position to provide automatic, tamper-proof securance of a sliding glass window 12 in its closed position. Such lock includes a carrying or housing means in the form of an outer circular tube 13 which is rigidly mounted via screws 14 (only one of which is visible in FIGS. 1 and 2) adjacent its upper and lower ends. Carried within the tube 13 is a right circular cylinder in the form of a circular tube 16 (a tube being a special case of a cylinder) which acts as a movement blocking memher to prevent the window 12 from being slid open once it is in its closed position. More particularly, the interior cylindrical surface of the tube 13 and the exterior cylindrical surface of the tube 16 coact to define a cylindrical path over which the tube 16 is moveable relative to the window 12 and tube 13; Both of the

tubes

13 and 16 have longitudinal sections thereof removed to define reentrant portions so that when the window 12 is in its closed position, a projecting flange 17 which is part of the edge of the window intersects the cylindrical path over which the tube 16 is moveable. Thus. such tube is moveable from a retracted position illustrated in FIG. 2 in which it is free ofopening movement of the window to the extended position illustrated in FIG. 1 in which the edge 18 of such tube engages behind the flange 17 of the window frame to'prevent such opening movement.

Releaseable means are provided as part of the deadlock for retaining the tube 16 in its extended blocking position illustrated in FIG. 1. That is, as will be described in more detail hereinafter, the carrying tube 13 and the locking tube 16 includes coacting cam surfaces which. upon rotation of the tube 16 relative to the tube 13, cause the tube 16 to axially move downward into a locking position in which locking surfaces on such cams engage to prevent reverse rotation of such tube and, hence, opening of the window. A lifting lever 19 I is secured to the-blocking tube and projects therefrom for manipulation to release the cam locking surfaces and allow authorized opening of such window.

It will be appreciated from the above that because of the rotary motion of the blocking tube on a cylindrical path to engage the edge 18 thereof behind the flange l7, tampering with the lock from the exterior of the window will not affect its integrity. More particularly, because the actual engagement between such lock and the window is behind the flange l7, insertion of tools and the like from the exterior of the window between it and its frame will not result in one being able to disengage the locking components.

As a salient feature of the instant invention. it includes means for automatically causing rotation of the blocking member upon the window being closed so that.

such closure will automatically result in the window I locking. More particularly, the edge 22 of the blocking tube 16 resulting from the removal of the longitudinal section includes a tab 23 which when the blocking member is in the retracted position shown in FIG. 2 ex-.

tends into the path of the window to its closed position.

Upon being closed, such window will engage the tab I and push it to cause rotation of the tube from its: retracted position to its extended position, i.e., bring the edge 18 of such tube into blocking position behind the flange 17. Not only will this rotation bring the edge 18 into position. but it will also cause the aforementioned locking surfaces of the coacting cams to become engaged to prevent reverse rotation of the blocking mem- I Reference is now made to FIGS. 3, 4 and 5 for a more" detailed description of the construction of the deadlock 11. As is illustrated in the exploded view of FIG. 3, the. carrying tube 13 is an elongated, right circular tube having a longitudinal section thereof removed. The removed section subtends an angle of less than 180, i.e..

around 90, in circular cross-section. Thus. such tube has a reentrant interior for retaining the locking tube 12 therein.

The interior cylindrical surface 24 of the carrying tube mates and coacts with the exterior cylindrical surface 26 of the block tube to limit movement of the interior blocking tube to a cylindrical path with respect to t the exterior tube. That is, the blocking tube isonlyaxially rotatable within the tube 13 and longitudinally moveable therewithin. However, translation of the interior tube 12 transversely of the common axis Ofthe tubes is prevented.

The outer carrying tube 13 is longer than. the inner blocking tube so as to completely enclose the ends of such inner tube. Upper andlower end caps 28 and 29 are also provided on the outer tube to retain the inner tube therewithin.

As mentioned previously, the edge 22 of the blocking tube is provided with a projecting lip 23 which extends into the path of the window when the tube is in the retracted position so that when such window is closed,

the tube isautomatically rotated into the locking position. As illustrated. such tab is turned inwardly of the tube and has a curved outer surface 31 for engagement with such window. This inward extension of the tab and such curved surfaces aid the transformation of the The releasable means for automatically retaining the blocking tube in its extended position once it reaches the same includes a pair of coacting cam surfaces associated with the carrying structure and the blocking tube. More particularly, the lower end cap 29 includes a flange portion 33 which extends into the interior of the carrying tube 13. The upper edge 34 thereof is the cam surface associated with the carrying structure. which surface coacts with the lower end cam surface 36 of the inner tube. This coaction is best illustrated with respect to the enlarged, partial view of FIG. 4. More particularly, the blocking tube 12 rests on the end cap 29 under the influence of gravity with its lower edge surface 36 in engagement with the upper edge surface 34 of such cap. Upon rotation of the inner tube 12 in the direction denoted by arrow 37, i.e.. upon rotation of the tube 12 from its retracted to its extended position by closure of the window, the coacting cam surfaces guide movement of the tube 12 to a location at which the cam surfaces are stepped sharply downward to provide generally vertical locking surfaces 38 and 39 which engage with one another to normally prevent reverse rotation of the blocking member. That is, the carrying tube will drop axially downward to a position at which the ledge provided by the locking surface 38 will prevent reverse rotation of the tube.

It will be noted that the coacting locking surfaces 38 and 39 are not truly vertical but rather are inclined slightly. More particularly, both of such surfaces include a directional component which extends in the direction of reverse rotation of the tube 12, i.e.. in the opposite direction as that denoted by the arrow 37, when viewed from above. This provides a reentrant catch which after the tube 12 has dropped into the locking position requires further rotation of the tube 12 in the extended direction prior to the surfaces 38 and 39 being completely disengageable. Thus. any attempt to force the window open against the lock will result in the surfaces 38 and 39 engaging in a manner which will prevent upward movement of the tube 12 for disengagement of such surfaces.

Another pair of cam surfaces are associated with the carrying structure and the blocking tube to assure that upon the tube 12 being rotated, it will drop vertically to engage the locking surfaces 38 and 39. To this end, the upper end cap 28 also includes a flange portion 41 which extends into the interior of the carrying tube 13 to a location at which its free edge surface 42 coacts with the upper end edge 43 of the tube 12. Such surfaces are provided with coacting, curved portions 44 which engage upon the tube 12 being rotated to drive the blocking tube downward into the locked position. Thus. possible hang-up of the tube so that it does not drop into the locked position is avoided. The cam surfaces 42 and 43 further include vertical coacting surfaces 46 which cooperate to define the limit of rotation of the tube into its retracted position.

The lift lever 19 is secured to the carrying tube 12 to enable manual lifting of the tube 12 and consequet disengagement of the locking surfaces 38 and 39 for authorized opening of such window. More particularly, as is best illustrated in FIG. 3, the lifting lever includes a stem 47 which depends downwardly from the blocking tube 12 through the end cap 29 to the exterior of the carrying structure. Such stem terminates in a U-shaped portion bringing a tab 48 to an appropriate location for manipulation to lift the tube 12.

It will be appreciated that to assure proper operation of the deadlock of the invention. it must be located in an appropriate orientation with respect to the edge of the opening to be closed, as well as a proper distance therefrom. The structure by which the carrying tube is to be rigidly mounted adjacent the edge of the opening is designed to facilitate such proper orientation. More particularly, as is best shown in FIG. 3,

fastener slots

51 and 52. respectively, extend through the flange portions of the end caps 28 and 29, and through the adjoining portions of the carrying tube. Such slots are elongated in a direction which is generally transverse of the common axis of the carrying and blocking tubes for the reception of suitable fasteners, such as the wood screws 54, for mounting the lock in place. Because such slots extend transversly of the axis, limited rotation of the lock is permitted at the time of installation of the lock to enable an appropriate orientation of such lock to be easily selected, dependent upon the particular sliding closure with which it is to be used.

It will be noted that the

slots

51 and 52 are angularly related to one another. Because of such, once the fas teners 54 are inserted therethrough and into the structure to which the lock is being mounted, the orientation of the lock is fixed relative to the closure. That is, the fasteners 54 will be maintained a predetermined distance apart because of their securance into the structure to which the lock is mounted. And because the slots are angularly related to one another, the fasteners can only be in specific positions within such slots in which this distance relationship is maintained. Thus, once the lock is mounted by the fasteners adjacent the opening to be controlled. rotation of the full lock, and consequent disorientation of the same relative to the window. is prevented.

In some uses of locking mechanisms. it is desirable that the mechanism, when in its locked position, prevent opening ofa closure from both the interior and exterior thereof. The deadlock of the mechanism is adaptable to such a situation in a simple and effective manner. FIGS. 6 and 7 illustrate a preferred arragement capable of double locking in this manner. More particularly, such figures illustrate the upper end of the lock, including an end cap incorporating a key operated lock. That is, the end cap 61 includes a typical key operated locking mechanism extending generally axially thereof. As is shown, the upper face 62 of the cap includes the slot for insertion of an operating key 63.. Such key controls the movement of a locking lever 64 between the unlocked position illustrated in FIG. 6 and the locking position shown in FIG 7. In the locking position, the lever 64 extends to a position above the raised curved portion 44 of the upper cam surface of the blocking tube to prevent such blocking tube from being manipulated upward. However, in the unlocked position illustrated in FIG. 6, the lever 64 is swung to a position at which it does not block such upward movement. In all other respects, the deadlock of the invention represented by FIGS. 6 and 7 is the same as the earlier embodiment which has been described.

Although the deadlock of the invention is particularly adaptable for securing sliding closures in their closed positions, it is also useful for locking swinging doors and windows. FIGS. 8 and 9 illustrates an embodiment of the invention which is so used. More particularly, the jamb 66 for a swinging door 67 is notched to accommodate the deadlock, which deadlock is rigidly mounted within such notch. This positioning of the lock relative to the door places it in the proper location so that when the door is moved to its closed position, it will intersect the cylindrical path of the blocking tube 68.

As can be readily seen from comparing the superimposed phantom position of the various parts in FIG. 9 with the solidly shown positions, upon movement of the door to its closed position. the same will engage the blocking tube and rotate it to bring the blocking edge 69 into locking therewith. Although not shown, it will be appreciated that this embodiment of the invention includes the cam surfaces and releasable lockingstructure described with respect to the embodiment of FIGS. 1 3.

It will be appreciated by those skilled in the art that various modifications and changes can be made without departing from the spirit of the invention. For example, the longitudinal dimension of the lock can be varied to suit particular exigencies. In fact. such lock can extend for the full length of the opening edge with which it is associated. Moreover, although the lock is shown along a vertical edge of the opening, it can be used with suitable adaptations along horizontal edges. And, although the lock is shown as an add-on" lock. its various features can be incorporated into the frame for an opening closure as an integral part thereof. Further. although the lock is shown mounted on the frame adjacent the opening closure, it is equally well suited for mounting on the opening closure itself for movement therewith so that it will coact with an appropriate stationary ledge or the like on the closure frame to provide the locking function. It is therefore intended that the coverage afforded applicant be limited only by the claims and their equivalents.

We claim:

1. A deadlock for securing an opening closure, such as a window or door. in its closed position within a frame defining the opening to be closed comprising a generally cylindrical. movement blocking member hav' ing a reentrant portion defining a blocking edge and rotatable on a circular cylindrical path; carrying means adapted for rigid mounting adjacent an edge of one of said opening closure and said frame for supporting said rotatable blocking member oriented with the axis of rotation of said blocking member generally parallel to an edge of the other one of said closure and said frame and at a location at which when said closure is in its closed position. said circular cylindrical path of said blocking member is intersected by said edge of the other one of said closure and said frame. said carrying means limiting motion of said blocking member to said cylindrical path between an extended position in which said blocking edge .of said blocking member blocks opening movement of said closure when it is in said closed position and a retracted position at which said blocking member is free of the opening movement of said closure; releasable means for retaining said blocking memher in said extended position with its blocking edge blocking opening movement of said closure; and wherein each of said movement blocking member and said carrying means has a circular cylindrical section surface which coacts and mates with the circular cylindrical section surface of the other to define said cylindrical path. said carrying means having a reentrant portion adjacent. said cylindrical section surface for accepting said edge of the other one of said closure and said frame to enable intersection of said path by said edge of said other one of said closure and said frame when said closure is in said closed position.

2. The deadlock of claim 1 for securing an opening closure in its closed position wherein said clocking member is positioned within said carrying means with an exterior surface thereof providing said cylindrical section surface mating with a corresponding interior cylindrical section surface of said carrying means.

3. The deadlock of claim 1 for securing anopening closure in its closed position wherein said blocking member includes a second edge which when said member is in said retracted position extends into the path of i in said extended position by said blocking member being rotated by said opening closure to said extended position.

5. The deadlock of claim 4 for securing an opening closure in its closed position wherein said releasable means for retaining said blocking member in said extended position includes a pair of coacting cam surfaces on said carrying means and said blocking member which guide axial movement of said blocking member to a locking position upon rotary movement of said.

blocking member on said cylindrical path.

6. The deadlock of claim 4 for securing an opening closure in its closed position wherein said carrying means is rigidly mountable adjacent a verticaledge of one of said opening closure and said frame. and said axis about which said blocking member is rotatable is a generally vertical axis.

7. The deadlock of claim 6 for securing an opening I closure in its closed position wherein said locking surfaces are inclined in the direction of reverse rotation of said blocking member to define a reentrant catch requiring further rotation of said blocking member in the direction of said extended position prior to the same being disengagable. and a manual lift lever is secured to said blocking member for facilitating said additional rotation of said blocking member in said extended position and lifting of said blocking member with respect'to said carrying means to disengage said locking surfaces.

8. The deadlock of claim 6 for securing an opening closure in its closed positionwherein a second pair of coacting cam surfaces are provided on said movement blocking member and said carrying means for driving.

said blocking member into said locked position with said locking surfaces engaged upon said blocking mem-' ber being rotated from said retracted to said extended position.

9. The deadlock of claim 4 wherein said movement blocking member is generally the shape of a circular cylinder having a longitudinal section thereof removed to provide generally opposing longitudinal edges on said blocking member. one of said edges being said edge which is engagable with said opening closure for rotating said blocking member from said retracted to said extended position, and the other one of said edges providing said blocking edge for blocking said opening movement of said closure member; and said carrying means is generally the shape ofa circulartube coaxially surrounding said blocking member tube. which carrying tube also has a longitudinal section thereof removed to enable said opening closure to intersect the cylindrical path of rotation of said cylinder therewithin.

10. The deadlock of claim 12 for securing an opening closure in its closed position wherein said carrying tube is rigidly mountable adjacent a vertical edge of said frame of said opening, said axis about which said blocking cylinder is rotatable is a generally vertical axis. and said cam surfaces of said releasable means are stepped downwardly to provide generally vertical locking surfaces which coact with one another to normally prevent reverse rotation of said blocking member from said extended position.

11. The deadlock of claim 6 wherein said cam surfaces of said releasable means are stepped downwardly to provide generally vertical locking surfaces which engage with one another to normally prevent reverse rotation of said blocking member from said extended position.

12. The deadlock of claim 9 wherein said cam surface associated with said blocking member is provided by an end of said circular cylinder, and an end cap is provided on each of the opposite ends of said carrying tube with a generally cylindrical flange portion of one extending into said carrying tube to a location adjacent the end of said blocking cylinder, the end of said flange portion providing said cam surface associated with said carrying means.

Claims

1. A deadlock for securing an opening closure, such as a window or door, in its closed position within a frame defining the opening to be closed comprising a generally cylindrical, movement blocking member having a reentrant portion defining a blocking edge and rotatable on a circular cylindrical path; carrying means adapted for rigid mounting adjacent an edge of one of said opening closure and said frame for supporting said rotatable blocking member oriented with the axis of rotation of said blocking member generally parallel to an edge of the other one of said closure and said frame and at a location at which when said closure is in its closed position, said circular cylindrical path of said blocking member is intersected by said edge of the other one of said closure and said frame, said carrying means limiting motion of said blocking member to said cylindrical path between an extended position in which said blocking edge of said blocking member blocks opening movement of said closure when it is in said closed position and a retracted position at which said blocking member is free of the opening movement of said closure; releasable means for retaining said blocking member in said extended position with its blocking edge blocking opening movement of said closure; and wherein each of said movement blocking member and said carrying means has a circular cylindrical section surface which coacts and mates with the circular cylindrical section surface of the other to define said cylindrical path, said carrying means having a reentrant portion adjacent said cylindrical section surface for accepting said edge of the other one of said closure and said frame to enable intersection of said path by said edge of said other one of said closure and said frame when said closure is in said closed position.

3. The deadlock of claim 1 for securing an opening closure in its closed position wherein said blocking member includes a second edge which when said member is in said retracted position extends into the path of said closure for engagement and movement by said closure upon it being moved to its closed position to cause automatic rotation of said blocking member from said retracted position to said extended position blocking opening movement of said closure.

4. The deadlock of claim 3 for securing an opening closure in its closed position wherein said releasable means is actuated for retaining said blocking member in said extended position by said blocking member being rotated by said opening closure to said extended position.

5. The deadlock of claim 4 for securing an opening closure in its closed position wherein said releasable means for retaining said blocking member in said extended position includes a pair of coacting cam surfaces on said carrying means and said blocking member which guide axial movement of said blocking member to a locking position upon rotary movement of said blocking member on said cylindrical path.

6. The deadlock of claim 4 for securing an opening closure in its closed position wherein said carrying means is rigidly mountable adjacent a vertical edge of one of said opening closure and said frame, and said axis about which said blocking member is rotatable is a generally vertical axis.

7. The deadlock of claim 6 for securing an opening closure in its closed position wherein said locking surfaces are inclined in the direction of reverse rotation of said blocking member to define a reentrant catch requiring further rotation of said blocking member in the direction of said extended position prior to the same being disengagable, and a manual lift lever is secured to said blocking member for facilitating said additional rotation of said blocking member in said extended position and lifting of said blocking member with respect to said carrying means to disengage said locking surfaces.

8. The deadlock of claim 6 for securing an opening closure in its closed position wherein a second pair of coacting cam surfaces are provided on said movement blocking member and said carrying means for driving said blocking member into said locked position with said locking surfaces engaged upon said blocking member being rotated from said retracted to said extended position.

9. The deadlock of claim 4 wherein said movement blocking member is generally the shape of a circular cylinder having a longitudinal section thereof removed to provide generAlly opposing longitudinal edges on said blocking member, one of said edges being said edge which is engagable with said opening closure for rotating said blocking member from said retracted to said extended position, and the other one of said edges providing said blocking edge for blocking said opening movement of said closure member; and said carrying means is generally the shape of a circular tube coaxially surrounding said blocking member tube, which carrying tube also has a longitudinal section thereof removed to enable said opening closure to intersect the cylindrical path of rotation of said cylinder therewithin.

10. The deadlock of claim 12 for securing an opening closure in its closed position wherein said carrying tube is rigidly mountable adjacent a vertical edge of said frame of said opening, said axis about which said blocking cylinder is rotatable is a generally vertical axis, and said cam surfaces of said releasable means are stepped downwardly to provide generally vertical locking surfaces which coact with one another to normally prevent reverse rotation of said blocking member from said extended position.