Rotating Push Lock For Sliding Doors

Abstract

A lock for sliding doors has a bolt carried by a plunger on one door and has a cross head movable into a strike on the passing door. The bolt is rotatable by a key operated core in the plunger, between two orientations. In unlocked, key-retaining orientation, the bolt is movable axially to carry its cross head from a retracted position behind the faceplate of its mounting to a projected position behind a strike on the opposite door, the face plate and strike having shaped openings to pass the cross head in that orientation. In locked, key-releasing orientation, the cross head is out of registry with the shaped openings and when engaged in the strike, prevents withdrawal of the bolt by forced separation of the doors. A spline groove and flatted sides on the bolt interengage with a shaped opening in the face plate to prevent bolt rotation at intermediate axial positions, and prevent bolt movement from end positions except after deliberate key rotation, which increases security and avoids inadvertent movement or disposition of the bolt to mar the passing door.

Description

BACKGROUND OF THE INVENTION

This invention relates to a lock for sliding doors. Such doors are commonly locked by projecting a bolt from the face of one door into a keeper on the overlapping door. Since such doors are not always mounted rigidly against separation of their overlapping faces, it is desirable to lock the bolt in the keeper so that it cannot be disengaged by separating the doors from each other.

Moreover, with sliding doors, it is desirable to prevent the lock bolt from being inadvertently projected against the face of the overlapping door when the doors are not in alignment, in order to prevent marring of the door face.

The present invention provides a locking bolt for sliding doors which can be advanced or retracted only after being first rotated by key operation, which cannot be rotated to locking position except when either fully advanced or fully retracted, and which interlocks with the face plate of its housing when retracted and with the strike of the opposite door when advanced, so that the bolt positively locks the doors against separation and cannot be inadvertently advanced into marring relation with the overlapping door.

In accordance with the invention, a manually operable plunger mounted on one door carries a bolt having a cross pin at its end which is rotatable between locking and release positions by a key operated lock core in the plunger. The face plate of the lock housing and the strike of the opposite door are provided with shaped openings to pass the cross pin of the bolt when the bolt is turned to release position by the key operated lock. When the bolt is rotated to locking position, the cross pin is carried behind a solid portion of the face plate or strike to prevent its axial movement. A groove on the bolt interengages with a tongue on the face plate at all intermediate axial positions of the bolt except its fully advanced or fully retracted positions, to prevent its rotation from released position to locking position except when fully advanced with its cross pin behind the strike or when fully retracted with its cross pin behind the face plate. Accordingly, the bolt can be advanced and retracted only when first rotated by the key mechanism to its release orientation, and must be either fully advanced or fully retracted before the key operated mechanism can be turned to locking orientation at which the key can be removed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is an isometric view of a pair of doors equipped with a lock embodying my invention;

FIG. 2 is a longitudinal sectional view through the door with its plunger in advanced position and engaged with the strike of the opposite door;

FIG. 3 is a section on the line 3--3 of FIG. 2 showing the lock bolt in locked position;

FIG. 4 is a sectional view line FIG. 2 but showing the lock plunger and bolt in retracted position;

FIG. 5 is an elevation of the face plate of the lock assembly, taken on the line 5--5 of FIG. 4;

FIG. 6 is an end elevation of the lock bolt, showing its relation to the face plate when rotated to release position;

FIG. 7 is a sectional view showing the lock bolt rotated to release position; and

FIG. 8 is an isometric view of a key-operated lock core adapted to be received in the cavity of the plunger.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The sliding doors 10 and 12 shown in FIG. 1 are mounted on spaced parallel tracks at the top of the door frame 14 for sliding movement past each other, and desirably engage longitudinal guides 16 at the bottom. The front door 10 contains a lock assembly 15 including a trim plate 18 and a plunger 20.

The plunger 20 is of generally oval cross section with flat sides, and may be in the nature of a padlock body and made from a padlock body blank. As shown in FIGS. 2 and 4, the plunger has side walls 22, edge walls 23 and an inner end wall 24, defining a blind cavity. The cavity is desirably formed of three overlapping bores which leave ridges on the inner face of the side walls 22, and such ridges are partially milled away to leave inward projecting lugs 25 and 26. Opposite the lower-most bore, the end wall 24 is bored at 28 for the reception of a guide pin 30 fixed as by riveting in the face plate 32. The rear end of the guide pin 30 is received in a bore formed between the lower edge wall 23 and a plug 34 fitted in the lower bore forming the plunger cavity. The plug is fixed in the bore by bayonet lock engagement of lugs 36 on its periphery with one set of lugs 25 and 26 on the plunger wall 22. The guide pin may contain a spring 35 mounted on an inner pin 37 to bias the plunger rearward to its retracted position shown in FIG. 4.

The upper face of the plug 34 is cut to form a cylindrical surface 33 conforming with the central cavity bore, and to form with the plunger walls a figure-8 cavity for the reception of a key-removable lock core 38 of a known type as shown in FIG. 8. See U.S. Pat. No. 3,206,959. The lock core contains a key plug 39 rotatable by a key 40 and having a pair of eccentric bores in its rear end for the reception of the legs of a throw member as described below. The core also has a projecting lug 42 at its side which is retractable with a special control key and which will engage over a lug 25 on the plunger side wall 22 when the core is inserted in the plunger cavity, to lock the core in the plunger.

The end wall 24 of the plunger contains a bore 43 coaxial with the central cavity bore to rotatably receive a bolt 44 integral with a throw member 46 bearing against the inner face of the end wall and supporting a pair of rearward legs 48 disposed to enter the bores in the rear of the key plug to connect the key plug for rotating the bolt 44. The projecting end of the bolt 44 carries a sleeve 50, fixed to it by a cross pin 52. The throw member 46 desirably carries a projecting stop pin 47 which swings against the plunger walls to limit rotation of the throw member.

The sleeve 50 has reduced collar portions 53 and 54 at its opposite ends which, in its fully advanced position (FIG. 2), and in its fully retracted position (FIG. 4), lie within a shaped opening 56 in the face plate 32 and are rotatable within that opening. As shown in FIGS. 5-7, the shaped opening 56 has opposite inward-projecting tongues 58 and may have flattened sides 59, all of which project inward beyond the periphery of the main portion 60 of the sleeve 50 between the reduced ends 53 and 54 and block its axial movement except when the bolt and sleeve are rotatively oriented in a release position by key rotation of the key plug to a plunger-unlocking position. As shown in FIGS. 6 and 7, to permit axial movement in that rotative position, the body 60 of the sleeve 50 has opposite longitudinal spline grooves 62 to pass the tongues 58, and has flats 63 on its sides to pass between the flattened sides 59 of the shaped opening in the face plate 32.

The shaped opening 59 also has a pair of opposite notches 64 to pass the cross pin 52 through the face plate 32.

The interengagement of the shaped sleeve 50 and the shaped opening 56 require the bolt to be either fully projected (FIG. 2) or fully retracted (FIG. 4) in order for it to be turned by the key from its release orientation (in which the key is trapped) to its locked orientation (in which the key is removable); and require the bolt and sleeve to be in release orientation as shown in FIGS. 6 and 7 (in which the key is trapped) in order for it to be moved between fully projected and fully retracted position or moved from either of those positions.

To lock the doors 10 and 12 to each other, the rear door 12 carries a strike 70 on its front face. The strike contains a shaped opening 72 for the reception of the bolt 44 as shown in FIGS. 2 and 3. The opening has a circular central portion to pass the large center portion 60 of the sleeve 50, and has a pair of opposite notches 74 to pass the ends of the cross pin 52 of the bolt. Such notches are oriented to lie opposite the notches 64 of the face plate and to pass the cross pin 52 when the bolt 44 and such pin 52 are rotated to release position as shown in FIG. 6. When the projected bolt 44 is rotated to locked position as shown in FIGS. 2 and 3, the pin 52 is out of alignment with the side notches 74 and locks the bolt in the strike 70. This effectively prevents forced separation of the doors or other withdrawal of the bolt from the strike 70.

When the bolt is to be retracted, it must first be rotated by operation of the key plug 39 of the core 38 from key-release position to key retaining position. This brings the shaped sleeve 50 into sliding registry with the shaped opening 56, and the bolt can then be moved axially to fully retracted position as shown in FIG. 4. During such movement the bolt cannot be rotated because of interengagement of the sleeve 50 with the shaped opening of the face plate 32. This ensures that the plunger and bolt will be fully retracted to carry the reduced forward end 54 of the sleeve into the plane of the face plate 32 and carry the cross pin 52 to a position behind the face plate as shown in FIG. 4. The bolt and key can then be rotated to key-release position, but this turns the cross pin out of registry with the notches 64 of the shaped opening and turns the shaped sleeve 50 out of registry with the shaped opening 56, so that the bolt is then locked in fully retracted position.

In summary, operation is as follows: When the bolt is retracted as shown in FIG. 4, the doors 10 and 12 are unlocked and free to slide past one another. The bolt 44 and its sleeve 50 is out of registry with the shaped opening in the face plate 32 and the bolt can not be projected toward the door 12 unless it is first rotated by deliberate operation of the key. This minimizes the danger that the bolt will be projected inadvertently to strike or mar the door 12.

When it is desired to lock the doors, they are brought to closed position, with the strike 70 opposite the face plate 32. The key 40 is then operated to rotate the bolt 44 and bring its sleeve 50 into registry with the shaped opening 56 in the face plate and the corresponding opening 72 in the strike. The bolt 44 is then advanced, and must be fully advanced, to the position shown in FIG. 2, where the cross pin 52 lies behind the strike 70 and the rear reduced portion 53 of the sleeve 50 lies in the plane of the face plate 32. The key is then rotated in reverse, to rotate the bolt to locked position. There is no lost motion between the key plug 39 and the bolt 44, so that the key 40 is trapped at all times when the bolt is axially movable, and can be removed only when the bolt is locked in either fully projected or fully retracted position.

In fully projected and locked position, the bolt 44 and its cross pin 52 secure the doors both against relative sliding and against separation. When the bolt is in retracted and locked position it can not be inadvertently or accidentally advanced to strike and mar the inner door 12, because it can be advanced only after it is deliberately rotated by key operation.

Claims

We claim:

1. A sliding door lock, comprising

a mounting having a face plate

an axially-movable plunger having a bolt rotatable therein and axially movable with the plunger and through the face plate between a retracted position and a projected position,

said bolt having means for engagement by a key-operated mechanism in the plunger to rotate the same between a locked orientation and a release orientation,

a cross head on the bolt which in said retracted position of the bolt lies behind the face plate,

shaped interengaging means on the bolt and mounting which permits axial movement of the bolt between said retracted and projected positions when the bolt is in release orientation, which prevents rotation of the bolt to locked orientation throughout movement of the bolt between the fully retracted and fully projected positions of the bolt, and which permits rotation of the bolt between locked and release positions only in the fully retracted and projected positions thereof,

and

a strike shaped to pass the cross head when the bolt is in its release orientation and to retain the cross head when the projected bolt is in locked orientation.

2. A sliding door lock as in claim 1 in which said shaped interengaging means comprises a shaped opening in the face plate having a spline engaging element at its periphery, and a coacting spline element movable with the bolt, extending axially thereof, and interacting with the spline engaging element throughout movement of the bolt between its retracted and projected positions so as to restrict the bolt to non-rotative axial movement between retracted and projected positions when the bolt is in release orientation and said spline elements acting to prevent axial movement of the bolt when the same is in other orientations.

3. A sliding door lock as in claim 2 in which the spline engaging element on the face plate is an inward projecting tongue and the spline element on the bolt is a continuous axial groove shaped to pass said tongue axially therethrough and connected at its ends with circumferential grooves.

4. A sliding door lock as in claim 2 in which the spline engaging element is a flat side edge extending chordally of the shaped opening of the face plate and the spline element on the bolt is a flatted side face disposed to pass said edge axially as the bolt is moved axially in release orientation and extending between circumferential grooves at the ends of said flatted side face to clear said flat side edge so as to allow bolt rotation when one of the grooves lies in the plane of the face plate.

5. A sliding door lock as in claim 1 in which said plunger is formed with a cavity for the reception of a key-operated mechanism,

said bolt is fixed to a throw member within said cavity, having means for engagement by the key-operated mechanism, and said bolt extending through a bore in the end wall of the plunger,

a sleeve on the projecting end of said bolt

a cross pin extending through the sleeve and bolt to fix the same together, and forming the cross head of the bolt,

said shaped interengaging means comprising circumferential grooves at the ends of said sleeve and an axial groove interconnecting the same, and an inward projecting lug on said face plate engaged in said grooves.

6. A sliding door lock as in claim 1 in which said plunger comprises an elongated body of flattened oval cross section, said bolt being rotatably carried in said plunger and having slidable guiding relationship in said face plate, and a guide pin fixed to the face plate and slidably received in a bore in the plunger, said pin and bore being in spaced parallel relation with the bolt and cooperating therewith to guide the plunger for axial movement between bolt-retracted and bolt-projected positions, and said pin and bolt being operative to mount said plunger on the face plate so as to form a self-contained assembly mountable on a door by said face plate.

7. A sliding door lock comprising a mounting having a face plate, an axially-movable plunger having a bolt rotatable therein and axially movable with the plunger and through the face plate between a retracted position and a projected position, said bolt having means for engagement by a key-operated mechanism in the plunger to rotate the same between a locked orientation and a release orientation, shaped interengaging means on the bolt and mounting which permits axial movement of the bolt between retracted and projected positions when the bolt is in release orientation, which prevents rotation of the bolt to locked orientation at intermediate axial positions of the bolt, and which permits rotation of the bolt between locked and release positions in both retracted and projected positions thereof, a cross head on the bolt, and a strike shaped to pass the cross head when the bolt is in its release orientation and to retain the cross head when the projected bolt is in locked orientation, in which said shaped interengaging means comprises a shaped opening in the face plate having an inward projecting element at its periphery, and an axial portion on the bolt having a cross section to pass through said opening in release orientation of the bolt and not to pass therethrough in locked orientation of the bolt, the bolt having a circumferential groove at each end of said axial portion shaped to allow free rotation of the bolt in said shaped opening, said grooves being located on the bolt to lie in said shaped opening when the bolt is in fully retracted position and in fully projected position and thereby to permit bolt rotation in those positions.