The present invention comprises a locking mechanism for use on breakout sliding doors and patio sliding doors. In particular, a device according to the present invention is designed for use with sliding doors whereby a first door is intended to slide over, and proximate to, a second door. More particularly, the invention relates to a recessed mechanical latching device for use on such doors so that the first door may slide over the entire length of the second door while also providing a robust latching mechanism.
Hospitals, laboratories, clean room facilities, and other commercial laboratories that use sliding doors and trackless breakout sliding doors have a need for a recessed positive latching device. Current prior art devices include one door comprising an outwardly extending latch mechanism on each side so that the latch mechanism can be engaged by a person on either side of the sliding door. However, the prior art mechanisms do not permit one sliding door to fully open and slide over the other sliding door. The lever-type handle on each side of the door blocks the door panels from opening to the fullest extent. What is needed is a recessed latch mechanism that is fully functional and durable that permits one sliding door to fully open and slide over the other sliding door. Such a device will allow for an increase in the amount of door opening space in an opened sliding position.
Other problems found in the prior art include springs breaking, parts wearing out, latching mechanisms not being able to accommodate a narrow rail doorframe, latching hooks extending from the doorjamb too far and getting caught on clothing or equipment, as well as bulky looking devices that are not aesthetically pleasing.
It is therefore an object of the present invention to overcome these limitations in the prior art. It is another object of the present invention to provide a self-latching device mechanism for use on both trackless breakout sliding doors and patio sliding doors. It is another object of the present invention to provide a recessed latch handle which permits the sliding door to open further than a regular handle.
The latching device of the present invention comprises a sliding door latching device for both trackless breakout sliding doors and patio sliding doors. In particular, this device comprises a positive sliding door latch with a self-latching mechanism. This latching device is more specifically designed for narrow rail as well as wide rail doorframes. One unique feature of this latching device includes an adjustable latch hook that does not substantially protrude beyond the door frame. This prevents objects from getting caught on the latch hook as such objects pass through the doorway. In addition, the latch housing does not contain any springs that have the potential for breakage. The material selected to fabricate the preferred embodiment of the device provides high durability in given operating conditions.
An additional novel feature of this new design is the latch handle options. In particular, this latching device can accommodate a lever handle as well as a novel recessed latch handle. A recessed latch handle in accordance with the present invention meets the needs of the breakout sliding doors used in commercial buildings and hospitals. This new recessed handle permits the sliding door to open further than a regular lever handle as the two sliding glass panels meet each other in the open position and breakout position.
A recessed latch handle according to the present invention provides the feature of permitting one sliding door to fully open and slide over the other sliding door. This feature, in turn, provides a trackless breakout sliding door with a wider opening in the breakout position. Prior art latch mechanisms would either interfere with a stationary panel or wall thereby preventing the door from breaking out in a 90 degree position, or the latch itself would extend out into the opening and thereby diminish the amount of space available for items passing therethrough.
A preferred embodiment of the present invention is fabricated from durable aluminum rather than plastic to prevent breakage as well as to prevent wear and tear of parts in the latch housing. Moreover, a latching mechanism according to the present invention does not include any springs which have been found to break with the prior art designs. In contrast, this present invention uses a durable memory rubber component.
The present invention also comprises an adjustable hook that is small and has been designed to extend from the latch housing rather than the door jamb, which allows the door to positively latch without any latching lining up problems, which can be found with other designs. This hook is small enough whereby it does not protrude too far out which prevents objects from catching on the latch as such objects pass through the doorway.
The recessed latch handle also is aesthetically pleasing to homeowners and architects looking for a new latching device that will blend into the doorframe in an unobtrusive way. The device can be powder-coated or anodized to accommodate many colors and thereby match the color of the existing doors.
As shown in
Recessed latching mechanism 10 further comprises adjustable latch hook 22 which, in turn, defines notch 24 for mating with the doorjamb strike. In operation, flap handle 16 is pressed or pulled away from the door jamb thereby raising latch hook 22 such that notch 24 no longer engages the door jamb strike and the door may slide freely into an open position. In a preferred embodiment of the present invention, notch 24 engages the door jamb strike with a 0.125 inch drop and flap handle 16 is pressed or pulled away from the doorjamb thereby raising latch hook 22 by 0.25 inch such that notch 24 completely clears the door jamb strike.
The assembly of recessed latching mechanism 10 is depicted in
Flap handle 16 defines aperture 32 designed to receive shaft 30. Shaft 30 extends through recessed box 12, offset 26, and flap handle 16. Shaft 30 defines an aperture 34 on its top designed to receive end cap 36. Flap handle 16 further defines aperture 38 designed to receive set pin 40; both of which operate to keep flap handle 16 fixedly engaged with shaft 30.
Recessed latching mechanism 10 further comprises latch housing 42, latch housing cover plate 44, a protective plate or scutcheon 46 and scutcheon insert 48. As shown, latch housing 42 is designed to receive latch housing cover plate 44, and scutcheon 46 is designed to receive scutcheon insert 48. Latch housing 42 further defines machined protrusion or seat 50 designed to resistively engage the front face of protrusion 52 of latch cylinder 54. Memory plug 62 is positioned within latch housing 42 and is designed to resistively engage the rear face of protrusion 52. In a preferred embodiment of the invention, memory plug 62 is fabricated from rubber.
Threaded set screw 58 passes through aperture 60 in latch housing 42 and threadedly engages aperture 56 of latch cylinder 54. Adjustable latch hook 22 threadedly engages set screw 58. In a preferred embodiment of the invention, threaded set screw 58 defines an outer thread to engage an inner thread defined in aperture 56 of latch cylinder 54. Similarly, set screw 58 defines an outer thread to engage an inner thread defined in latch hook 22.
Completing the assembly depicted in
Additional assembly and benefits of the device are shown in
Devices according to this invention may be used alone or in conjunction with automatic sliding door closing devices for trackless breakout sliding doors and patio sliding door closer devices. The alignment of the positive latching feature accommodates the automatic self-closing devices found in hospitals with respect to Intensive Care Unit doors, clean room facilities, fire doors, and laboratories. This positive latching device also may be used with the automatic closing device used on the patio sliding doors for energy efficiency, convenience, security, and safety of having a patio sliding door automatically closed and latched.
As one will readily determine, a recessed latching mechanism according to the present invention is extremely easy to use with just a slight finger touch thereby making it very convenient. Another embodiment of the present invention will accommodate a regular latch handle if so desired. Typically, a device according to the present invention is machined into the door on site but also could be machined into the door at the factory. Machining the latching device into the door allows for better alignment of the positive latching feature.
The latching mechanism of the present invention overcomes the shortcomings of the prior art. Although the invention has been described in considerable detail with respect to particular embodiments of Applicant's latching mechanism, it will be apparent that the invention is capable of numerous modifications and variations, apparent to those skilled in the art, without departing from the spirit and scope of the invention.