Removable cylinder locked mullion assembly

Abstract: A mullion assembly (10) mountable between a floor (14) and a door frame (12) includes an engagement assembly (20) attached to either the floor or the door frame. A mullion (16) has a mullion cavity (17) and is positioned in removable attachment with the engagement assembly and a cylinder lock assembly (22) is positioned in the mullion cavity. The cylinder lock assembly (22) has a key lock cylinder (23) for positioning in either a locked position to engage the engagement assembly and hold the mullion in an upright position in the door frame or in an unlocked position disengaged from the engagement assembly to permit removal of the mullion from the doorway.

Description: This invention relates to a mullion assembly and more particularly to a removable mullion assembly controlled by a key cylinder lock mechanism. Mullions are vertically orientated doorway inserts that allow use of single doors in double door frames. Conventionally, mullions are centred in a double doorway and attached with screws or bolts to fittings inset into the floor and the top of the door frame. Two strikes are provided on opposing sides of the mullion to accommodate latches of two single size doors that are respectively hinge mounted on opposite sides of the door frame. When unobstructed access through the double door is needed, conventional mullions must be unscrewed or unbolted from the inset fittings. This can be time-consuming and difficult procedure, and normally requires two people. One person must hold the mullion while the other person unscrews or unbolts the mullion from the fittings. However, repeated removal and replacement of the mullion can also cause problems, with the fittings tending to become loose with time, or screw threads being stripped or damaged. To overcome this problem, removable mullions that do not require unscrewing or unbolting are known. However, known mullion assemblies are disadvantageous for many applications because the mullion release system is not protected against damage or unauthorised removal by vandals. What is needed is an easily-pivoted mullion assembly that can be snapped into an upright position to secure hinged doors, does not require more than one person to remove or align and is not removable by unauthorised persons. GB-A-1 482 828 discloses a fire-proof door with a mullion assembly that is in accordance with the preamble of claim 1. According to the present invention, there is provided a mullion assembly mountable between a floor and a door frame, the mullion assembly comprising an engagement assembly for attachment to the floor or the door frame, and a mullion defining a mullion cavity, the mullion being positionable in removable attachment with the engagement assembly; and a lock assembly is positioned in the mullion cavity, the lock assembly having means configured for positioning in a locked position to engage the engagement assembly and hold the mullion in the door frame and in an unlocked position disengaged from the engagement assembly to permit removal of the mullion from the doorway, characterised in that said lock assembly means is a cylinder lock assembly means (23,28) comprising a key operated lock cylinder and a cylinder sleeve and in that the engagement assembly comprises a flange with a flange aperture therethrough, positioned to accommodate the key operated lock cylinder in locking engagement inside the mullion cavity (17), and the key lock cylinder of the cylinder lock assembly projects through the flange aperture in the locked position and is pushed out of the flange aperture in the unlocked position. The cylinder lock assembly can include a compression spring connected between the key lock cylinder and the flange of the engagement assembly, with the compression spring being biassed to force the key lock cylinder out of the flange aperture. When the mullion assembly is locked in an upright position, this biassing force exerted by the spring is resisted by a cylinder cam attached to the key lock cylinder. The cylinder cam is rotatable by a key to engage an abutment defined by the engagement assembly, preventing retraction of the cylinder lock assembly from its locked position within the flange aperture. For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: - Figure 1 is a perspective view of a double door frame having a mullion assembly mounted between a retaining element and an engagement assembly respectively positioned at the top and bottom centre of the door frame as illustrated; Figure 2 is a perspective view of the mullion assembly of Figure 1, the mullion assembly being rotated away from the engagement assembly after disengagement of the mullion through actuation of a cylinder lock assembly; Figure 3 is a perspective, broken away view of the mullion assembly, illustrating the locked connection between the engagement assembly attached to the floor, the mullion, and the cylinder lock assembly positioned within the mullion to control engagement of the mullion with the engagement assembly; Figure 4 is a top, cutaway view of the mullion assembly of Figure 3, shown in its locked position; and Figure 5 is a top, cutaway view of the mullion assembly of Figure 4, shown in an unlocked position with a key lock cylinder of the cylinder lock assembly withdrawn from its locked connection with a flange projecting from the engagement assembly. As shown in Figure 1, a mullion assembly 10 is installed between a standard double door frame 12 and a floor 14. The mullion assembly 10 includes a mullion 16 that is fitted between a retaining element 18 and an engagement assembly 20. The retaining element 18 is permanently attached to the door frame 12 (as illustrated) or the floor, and is configured to have several projections (not shown) that guide placement of the mullion and prevent its dislodgement when the mullion is positioned in an upright, locked position. The engagement assembly 20 is also permanently affixed to either the floor (as illustrated) or the door frame, directly opposite the retaining element 18. As best seen in Figures 3, 4 and 5, the engagement assembly 20 has an upwardly projecting flange 24 that defines a flange aperture 25 passing therethrough. As best seen in Figures 1 and 3, the mullion 16 defines a mullion cavity 17 that can be fitted over the engagement assembly 20. The mullion 16 can be constructed from steel or aluminium by conventional techniques such as extrusion, stamping, folding or other known metal working techniques. As best seen with reference to Figures 3, 4 and 5, the cavity 17 also accommodates a cylinder lock assembly 22, which includes a key lock cylinder 23, cylinder sleeve 28 and compression spring 30. The mullion includes a sleeve bracket (26) that terminates at one end with an abutment (27) for bearing the cylinder lock assembly. The compression spring 30 engages both the sleeve bracket 26 and the sleeve 28 of the key lock cylinder 23, being normally biased to urge the key lock cylinder out of its locked position passing through the flange aperture 25. This spring force is resisted by a cylinder cam 32 that can be rotated by a key to engage the abutment 27, effectively locking the cylinder lock assembly 22 and the attached mullion 16 to the flange 24 of the engagement assembly. In operation, as seen with reference to Figures 4 and 5, release of the mullion 16 from the retaining element 18 and engagement assembly 20 follows in response to activation of the key lock cylinder 23. This release is simple and secure, with a key turn breaking the locked connection between the cylinder lock assembly 22 and the engagement assembly 20. In this locked position (Figures 1 and 4), the cylinder lock assembly 22 projects through the flange aperture 25 of the flange and is maintained in position against the force of compression spring 30 by the engagement between the cylinder cam 32 and the abutment 27. However, when a key (not shown) is used to rotate the cylinder cam 32 away from contact with the abutment 27, the compression spring 30 expands, pushing the key lock cylinder out of the flange aperture as seen in Figure 5. This breaks the connection between the mullion 16 and the engagement assembly 20, and allows the mullion 16 to be rotated out of its vertical, locked position and removed to improve doorway access (Figure 2). Replacement of the mullion 16 is also simple and efficient, with the mullion being manoeuvred into position, the key lock cylinder 23 being forced inward until it passes through the flange aperture 25, and a key rotating the cylinder cam 32 until it engages the abutment 27 of the engagement assembly. As will be appreciated, other mechanisms for engaging the engagement assembly are also possible, including bolts, latches or other throw mechanisms triggered by rotation of the cylinder cam to engage the engagement assembly. In addition, it is also possible to reverse the orientation of the mullion by positioning the cylinder assembly and engagement assembly near the top of doorway.

Claims: A mullion assembly (10) mountable between a floor (14) and a door frame (12), the mullion assembly comprising an engagement assembly (20) for attachment to the floor (14) or the door frame (12), and a mullion (16) defining a mullion cavity (17), the mullion being positionable in removable attachment with the engagement assembly (20); and a lock assembly (22) is positioned in the mullion cavity (17), the lock assembly (22) having means (23,28) configured for positioning in a locked position to engage the engagement assembly (20) and hold the mullion (16) in the door frame (12) and in an unlocked position disengaged from the engagement assembly (20) to permit removal of the mullion (16) from the doorway, characterised in that said lock assembly means (23,28) is a cylinder lock assembly means (23,28) comprising a key operated lock cylinder (23) and a cylinder sleeve (28) and in that the engagement assembly (20) comprises a flange (24) with a flange aperture (25) therethrough, positioned to accommodate the key operated lock cylinder (23) in locking engagement inside the mullion cavity (17), and the key lock cylinder (23) of the cylinder lock assembly (22) projects through the flange aperture (25) in the locked position and is pushed out of the flange aperture (25) in the unlocked position. An assembly according to claim 1, wherein said engagement assembly (20) is attached to a said door frame (12). An assembly according to claim 1, wherein said engagement assembly (20) is attached to a said floor (14). An assembly according to claim 1, 2 or 3, wherein a retaining element (18) is provided for attachment to the floor (14) or the door frame (12) so that the mullion (16) is positionable in removable attachment between the retaining element (18) and the engagement assembly (20), respectively. An assembly according to any one of the preceding claims, wherein the cylinder lock assembly (22) further comprises a compression spring (30) connected between a sleeve (28) of the lock cylinder (23) and a sleeve bracket (26) of the mullion (16), the compression spring being biassed to force the lock cylinder (23) out of the flange aperture (25). An assembly according to claim 5, wherein the cylinder lock assembly (22) has a cylinder cam (32) rotatable by a key to engage an abutment (27) of the sleeve (26). A double door and door frame incorporating a mullion assembly according to any one of the preceding claims.

Inventors: COHRS RICHARD B, PRUCINSKY MATTHEW S, VITT ROGER A, COHRS, RICHARD B., PRUCINSKY, MATTHEW S., VITT, ROGER A.
Applicants: VON DUPRIN INC, VON DUPRIN, INC.
Application year: 1995
Main classification: E06B1
IPC codes: E06B1