초록 ▼

A security lock for sash windows includes an elongated cam that revolves in order to engage a keeper. The security lock also includes a tab that urges the cam against a wall of a housing to provide extra security. Once the cam contacts the housing wall it will not rotate to open as occurs in convent

A security lock for sash windows includes an elongated cam that revolves in order to engage a keeper. The security lock also includes a tab that urges the cam against a wall of a housing to provide extra security. Once the cam contacts the housing wall it will not rotate to open as occurs in conventional sash locks. A groove and a race within the top inside of the housing direct a guide affixed to the top of the cam a), initially in a circular direction, and b), finally into a lateral direction into engagement with a locking stud on the wall of the housing. A rotating tab affixed to the handle axle causes the final cam movement during the locking process.

대표청구항 ▼

I claim: 1. A lock comprising: a housing, said housing including an indent, a race, and a locking stud extending inward from a side wall of the indent adjacent to a terminal end of the race, a cam, said cam positioned within said indent, said cam defining a well, a rotatable tab, an axle, said tab

I claim: 1. A lock comprising: a housing, said housing including an indent, a race, and a locking stud extending inward from a side wall of the indent adjacent to a terminal end of the race, a cam, said cam positioned within said indent, said cam defining a well, a rotatable tab, an axle, said tab mounted on said axle within said well, whereby upon rotation of said axle, said tab revolves to urge said cam into a locked posture against said housing, and wherein said tab is pivotable by more than 180�� from an unlocked position to a locked position within said well. 2. The lock of claim 1 wherein said locking stud is V-shaped. 3. The lock of claim 1 further comprising a handle, said handle affixed to said axle. 4. The lock of claim 1 wherein said locking cam defines an axle port, said axle port for receiving said axle. 5. The lock of claim 4 wherein said axle port is elongated, said cam slideable on said axle along said axle port. 6. The lock of claim 4, wherein the cam and the axle port are elongated along the same axis. 7. The lock of claim 1 wherein said tab is pivotably mounted within said well, the well being formed on a bottom side of the cam. 8. The lock of claim 1 wherein said cam includes a locking stud notch formed on a curved outer edge thereof, said locking stud notch for selectively receiving said locking stud. 9. The lock of claim 1 wherein said housing defines a groove. 10. The lock of claim 1 wherein said cam is elongated and includes a guide affixed to said cam, said guide being positioned in said race of said housing. 11. The lock of claim 1 further comprising a keeper, said cam engaging said keeper. 12. The lock of claim 1 wherein the well of the cam is entirely surrounded by a wall, the cam including a first rounded lobe and a second rounded lobe formed in the wall, the first rounded lobe being larger than the second lobe. 13. The lock of claim 1, wherein the lock is a window sash lock. 14. A lock for a window sash comprising: a housing, said housing defining an indent, a rotatable and slideable cam, said cam including a well entirely surrounded by a wall formed on a bottom side of the cam, and an elongated axle port extending from a top side to the bottom side of the cam, an axle, said axle positioned within said axle port to allow said cam to selectively rotate and slide within said indent, said cam includes a first rounded lobe and a second rounded lobe formed in said wall that receives a rotatable tab therein, said tab is mounted to said axle, whereby upon rotation of said axle, said tab revolves to urge said cam into a locked posture against said housing. 15. The lock of claim 14 further including a V-shaped locking stud extending inward from a side wall of the indent of the housing, said cam including a locking stud notch formed on a curved outer edge thereof, wherein said cam is adapted to be rotated and slid so said V-shaped locking stud engages said cam notch. 16. The lock of claim 14 further comprising a handle, said handle attached to said axle for turning said cam. 17. The lock of claim 14 wherein said cam is elongated. 18. In a locking system for a sash type window in which a keeper mounted on a window frame is engageable with a lock mounted on a window sash to selectively immobilize sash movement, the improvement comprising: a lock, said lock comprising a housing, said housing defining an indent, a cam, said cam positioned in said indent for rotation into engagement with said keeper, said cam defining an elongated axle port, an axle, said axle contained within said axle port, said cam further defining a well, a tab, said tab attached to said axle and contained within said well, said tab for urging said cam along said axle port into contact with said housing and into engagement with said keeper to prevent sash movement, wherein rotation of the tab urges a locking stud of the housing into a locking stud notch formed on a curved outer edge of the cam. 19. The locking system of claim 18 wherein said housing includes a race, a V-shaped locking stud extending inward from a side wall of the indent of the housing, and wherein said cam includes a guide positioned in said race of the housing, whereby upon rotation of said cam said guide directs said cam against said locking stud. 20. The locking system of claim 18 wherein the well of the cam is entirely surrounded by a wall, the cam including a first rounded lobe and a second rounded lobe formed in the wall, the first rounded lobe being larger than the second lobe.