Movable or removable closures – With means mounting closure for swinging – With latch or lock
Reexamination Certificate
1999-07-29
2001-01-23
Redman, Jerry (Department: 3634)
Movable or removable closures
With means mounting closure for swinging
With latch or lock
C070S103000, C070S130000
Reexamination Certificate
active
06176041
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention generally relates to a casement defining an opening in a structure, such as a wall, in combination with a closure element that is movable with respect to the casement for opening or closing at least a portion of the casement opening; and, more particularly, to a latch mechanism for fixing the relative position of the closure element with respect to the casement, preferably in the closed position.
2. Related Art
A casement assembly comprising a combination of a casement frame and a closure element is well known and finds common examples in security screens, sliding glass doors, or double hung windows, to name a few examples. Generally, the casement frame is positioned within a wall or similar structural element to define a passage therethrough. The closure element (generally a window, screen or door) is movable (generally slidable or pivotal) with respect to the casement frame for alternatively opening or closing the passageway.
For safety, it is common to provide a latch mechanism for locking the closure element in a fixed position relative to the casement frame, preferably in the closed position. Previous latch mechanisms typically include one or more locking rods mounted to the closure element and laterally movable between a retracted and extended position for inserting and removing an outer end of the bar into and out of engagement with the casement frame to prevent the movement of the closure element with respect to the casement frame. A laterally movable or rotatable handle or knob was directly mechanically coupled to the inner end of the rod for moving the rod between the extended and retracted positions as the handle is slid or rotated. The direct mechanical coupling between the rod inner end and the knob or handle typically included rotatably pinning the end of the rod to the handle or providing an intermediate link having one end pinned to the rod and the other end pinned to the handle or knob. Examples of such latch mechanisms with direct mechanical links are illustrated in U.S. Pat. No. 2,708,478, filed May 17, 1955, U.S. Pat. No. 2,883,225, filed Oct. 16, 1953, U.S. Pat. No. 4,362,328, issued Dec. 7, 1982, U.S. Pat. No. 4,803,808, issued Feb. 14, 1989, U.S. Pat. No. 5,090,750, issued Feb. 25, 1992, U.S. Pat. No. 5,595,408, issued Jan. 21, 1997, and U.S. Pat. No. 5,806,353, issued Sep. 15, 1998 to name a few.
A disadvantage of the prior art latches lies in the direct mechanical linkage, which can often be difficult to extend and retract because of the inherent friction or resistance in the mechanical linkages. Many of the mechanical linkages change angular orientation with respect to the handle or knob as it is rotated, resulting in quickly varying relatively small lever arms that require applying relatively large and varying rotational forces to the handle or knob to effect the extension or retraction. The magnitude and varying nature of the operational force results in jerky operation and sometimes a very high initial force. The combination of these effects can often lead to the user having to apply a relatively very large initial force until the inherent friction or resistance is overcome, resulting in the user feeling as if the latch mechanism has broken away. An additional problem lies in that the various components are typically metal and the linkages can rust, increasing the force necessary to overcome the additional resistance and exacerbating the initial force problem.
SUMMARY OF THE INVENTION
There is a desire to have a casement enclosure assembly with a latch that addresses the disadvantages of the prior art and permits the easy and repeatable locking/unlocking of the closure with respect to the casement. The invention addresses this desire by ameliorating the prior art disadvantage by providing a latch mechanism that requires a relatively low initial force alone or in combination with a casement assembly. The casement assembly comprises a casement frame that defines a passageway and a closure element that is moveably mounted to the casement frame and closes at least a portion of the passageway. The latch mechanism comprises a rod and a cam for operably moving the rod. The rod has inner and outer ends and is slidably mounted to the closure element for lateral movement between an extended position, preventing the movement of the closure element relative to the casement frame, and a retracted position, permitting the sliding movement of the closure element relative to the casement frame. The cam has at least one eccentric surface that is in substantially constant abutting relationship with the rod inner end and is rotatably mounted to the closure element for rotation between a first position and a second position for moving the rod between the retracted and extended positions.
The latch can further comprise a biasing device that biases the rod inner end against the eccentric surface. The biasing device is operably coupled between the rod and one of the closure element and the casement frame. Preferably, the biasing device comprises a mounting bracket having an eyelet that slidably receives the rod and a coil spring that is concentrically positioned relative to the rod and having one end connected to the bracket and another end connected to the rod whereby when the rod is in the extended position, the spring is compressed and applies a biasing force to the rod to urge the rod toward the retracted position.
The latch can further comprise a handle mounted to the cam for rotating the cam between the first and second positions. The handle is preferably mounted to the cam at a location is spaced from the cams rotational axis.
The cam can also comprise a stop that abuts the rod when the cam is in the second position to prevent the continued rotation of the cam beyond the second position. Preferably, the stop is a projection that extends away from the eccentric surface.
The casement assembly can include a catch that couples with the rod outer end when the rod is in the extended position to form the interference relationship. The catch can be a portion of the casement that the rod outer end overlies or an opening formed in the casement frame and sized to receive the outer end of the rod. There can also be multiple openings provided along the casement frame to permit the fixation of the closure element at discreet locations along the casement frame.
REFERENCES:
patent: 2708478 (1955-05-01), Wolf et al.
patent: 2883225 (1959-04-01), Akehurst
patent: 3953061 (1976-04-01), Hansen et al.
patent: 4005886 (1977-02-01), Lirette
patent: 4362328 (1982-12-01), Tacheny et al.
patent: 4803808 (1989-02-01), Greisner
patent: 5090750 (1992-02-01), Lindqvist
patent: 5244238 (1993-09-01), Lindqvist
patent: 5280755 (1994-01-01), Batur
patent: 5595408 (1997-01-01), Jeche
patent: 5791700 (1998-08-01), Biro
patent: 5806353 (1998-09-01), Pages
patent: 2144170 (1985-02-01), None
Kananen Ronald P.
Rader Fishman & Grauer
Redman Jerry
Roberts James Wilford
LandOfFree
Casement assembly and a latch mechanism therefor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Casement assembly and a latch mechanism therefor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Casement assembly and a latch mechanism therefor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2475946