This disclosure generally relates to latches and, in particular, relates to an automatic rotary latch for sliding or hung window sashes.
Existing hung and slider windows utilize various means for locking the primary movable sash to the fixed or secondary sliding sash. Traditionally, latches are utilized to lock window sashes. The window sashes are locked when a latch is engaged with a striker. To unlock the window, an operating lever is used to pull the latch or pivot the latch to a retracted position, clearing the latch from the striker. Once the latch is cleared from the striker, the window is slid open. To lock the window, the operating lever is used to push or pivot the latch to a locked position, where the latch engages the striker. Currently there exists a number of self-latching window sash locks available on the market. Self-latching locks automatically latch the window sashes after the window sashes are closed. Thus when the latch has reached the same level as the striker it latches the window in the closed position automatically. However, to open the window the operating lever still needs to be held in order to allow the latch to clear the striker as the window is slid open. Once the latch clears the striker, the operating lever is released and the latch returns to an extended position or locked position. The action of opening such a window requires the operator to use one hand to unlock the self-latching lock, while simultaneously using the other hand to slide the window. Not only is this action awkward to perform but also it can be very difficult to perform on large windows, windows without finger grips, windows with more than one latch and windows which have limited and restricted access. A need for an automatic sash lock still remains, wherein the operator interfaces with the sash lock once and has both hands available for sliding the window open and shut, while the latch automatically unlatches and latches to the striker.
An improved latch is disclosed. The latch comprises a chassis that defines a recess. The latch also comprises a bolt that is biased towards an extended position and that is slidably received in the recess. The bolt comprises a passage and a notch. The latch also comprises a plunger that is biased towards an extended position and which is slidably received in the passage. The chassis comprises an opening on which a post of a rotary latch is pivotally mounted. The bolt comprises a notch and the rotary latch comprises a protrusion that is biased towards the notch of the bolt when the bolt is pulled into a retracted position or when the bolt slides inwardly towards the chassis and the protrusion of the rotary latch rotates towards the notch in the bolt. When the bolt is released to the extended position, the plunger slides inwardly towards the chassis and the protrusion of the rotary latch disengages from the notch of the bolt as the rotary latch rotates away from the notch.
In a refinement, a method for operating a latch for a window sash is disclosed. The method comprises biasing the bolt and the plunger towards an extended position. The bolt is slidably received in the recess of the chassis and the plunger is slidably received in a passage of the bolt. The method further comprises unlocking the latch by retracting from the extended position to the retracted position by engaging the notch on the bolt with the protrusion on the rotary latch to hold the bolt in the retracted position. The rotary latch is pivotally connected to the chassis and biased towards the notch. The method further comprises opening the window sash that results in the plunger engaging the striker as the window is opened, thereby retracting the plunger and causing the protrusion on the rotary latch to rotate and disengage from the notch which results in the bolt and the plunger moving back to the extended position upon clearing the striker. The method also comprises closing the window sash so the bolt and the plunger retract upon engaging the striker, before releasing to the extended position upon clearing the striker, and locking the latch.
In another refinement, another improved sash lock is disclosed. The sash lock comprises a chassis that defines a recess and a cover, which is mounted to the chassis. The cover comprises a handle, which is coupled to a bolt. The bolt is accommodated in the recess and is biased towards an extended position. The bolt comprises a passage and a notch. A plunger is biased towards the extended position and slidably received in the passage. The chassis comprises an opening for pivotally mounting a post of a rotary latch to the chassis. The rotary latch comprises a protrusion that is biased towards the notch in the bolt. In a retracted position, the bolt is held inwardly towards the chassis and the protrusion of the rotary latch engages the notch in the bolt. In an extended position, the bolt is released when the plunger slides inwardly towards the chassis and the protrusion disengages from the notch as the rotary latch rotates away from the notch.
Other advantages and features will be apparent from the following detailed description when read in conjunction with the attached drawings.
For a more complete understanding of the disclosed apparatus and method, reference should be made to the embodiments illustrated in greater detail in the accompanying drawings, wherein:
a-2c are perspective and bottom views of the latch of
a-3f are perspective views of various disclosed covers and handles or triggers;
a-4e are perspective views of the disclosed handle and bolt illustrating the use of gears on the handle (or trigger) that enmesh with gears on the bolt;
a is a top perspective view of the chassis and bolt shown in
a-6d are exploded perspective, top and bottom views the plunger, rotary latch and plunger spring as shown in
a- 8c are perspective and bottom plan views of the latch shown in
a-9c are perspective and bottom views of the chassis, bolt and plunger shown in
a-10d are exploded perspective, top and bottom plan views of the plunger and rotary latch of the embodiment of
It should be understood, of course, that this disclosure is not limited to the particular embodiments illustrated herein.
Referring to
Referring to
In
In
In
Once the handle 104 unlatches the bolt 108 from the striker by locking the bolt 108 in the retracted position as shown in
Referring to
The operator needs to interface only once with the latch 100 when operating the handle 104 to unlock the latch 100. Once the latch 100 is unlocked and the bolt 108 is retracted, the operator may release the handle 104 and may use both hands to open the window as the flat side 143 and leading edge 109 of the bolt 108 automatically clears the striker when in the retracted position and are held in the retracted position by the protrusion 144 being lodged in the notch 136 as shown in
In
While only certain embodiments have been set forth, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the spirit and scope of this disclosure and the appended claims.
This application claims priority under 35 U.S.C. 119(e) to U.S. Provisional Patent Application No. 61/153,739 filed on Feb. 19, 2009, the disclosure of which is incorporated by reference in its entirety.
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Number | Date | Country | |
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20100207403 A1 | Aug 2010 | US |
Number | Date | Country | |
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61153739 | Feb 2009 | US |