Door lock with clutch
A door lock that includes a clutch mechanically arranged between a drive motor and a lock drive with the clutch having a clutch gear that is movable between engaged and disengaged positions to selectively couple and uncouple the drive motor from the lock drive from the drive motor. The clutch gear may be movable along a pathway between engaged and disengaged positions, e.g., in a direction perpendicular to a rotation axis of the clutch gear. The clutch gear may selectively couple and uncouple the drive motor from the lock drive based on movement of the drive motor.
1 . A door lock comprising:
a body adapted to be mounted to a door and having a base, wherein the base has a curved slot formed therein;
a lock drive movably mounted to the base of the body and adapted to move a lock mechanism between locked and unlocked positions;
a thumb turn movably mounted to the body and adapted for manual movement between at least two positions, the thumb turn being coupled to the lock drive such that movement of the thumb turn moves the lock drive;
a drive motor mounted to the base of the body;
a clutch gear having a pivot axis, the clutch gear being mounted in the curved slot of the base, wherein:
the clutch gear is configured for displacement along the curved slot between an engaged position in which the clutch gear is coupled with the lock drive and a disengaged position in which the clutch gear is not coupled with the lock drive,
the clutch gear is configured for rotation about the pivot axis,
the clutch gear is operably coupled with the drive motor such that movement of the drive motor effects rotation of the clutch gear about the pivot axis, and
the rotation of the clutch gear about the pivot axis effects displacement of the clutch gear along the curved slot to selectively couple or uncouple the drive motor to or from the lock drive in response to movement of the drive motor to rotate the clutch gear; and
a forward drive gear and a reverse drive gear that are mounted to the body and coupled to the lock drive,
wherein the curved slot has a first position where positioning the pivot axis of the clutch gear causes the clutch gear to engage with the forward drive gear,
wherein the curved slot has a second position where positioning the pivot axis of the clutch gear causes the clutch gear to engage with the reverse drive gear, and
wherein when the drive motor is energized for a predetermined interval of time the clutch gear is displaced between the engaged position and the disengaged position.
2 . The door lock of claim 1 , wherein the clutch gear is operably coupled with the drive motor by a drive gear and the clutch gear is configured for displacement along the curved slot by reaction forces arising from interactions between the clutch gear, the drive gear and the curved slot.
3 . The door lock of claim 2 , wherein the curved slot is arranged in a plane that is perpendicular to the pivot axis.
4 . The door lock of claim 1 , wherein rotation of the drive motor in a forward direction displaces the clutch gear toward the first position of the curved slot, and rotation of the drive motor in a reverse direction displaces the clutch gear toward the second position of the curved slot.
5 . The door lock of claim 1 , wherein the pivot axis of the clutch gear is positionable between the first position and the second position such that the clutch gear is disengaged from both the forward drive gear and the reverse drive gear and such that the drive motor is uncoupled from the lock drive.
6 . The door lock of claim 5 , wherein the lock drive includes a drive wheel that is mounted to the body and that is coupled to both the forward and reverse drive gears such that movement of the forward drive gear or the reverse drive gear rotates the drive wheel.
7 . The door lock of claim 6 , wherein the thumb turn is coupled for movement with the drive wheel such that movement of the thumb turn moves the drive wheel, and movement of the drive wheel moves the thumb turn.
8 . The door lock of claim 1 , further comprising a transmission coupled between the drive motor and the clutch gear.
9 . The door lock of claim 8 , wherein the transmission includes a pair of bevel gears including a first bevel gear mounted to a drive shaft of the drive motor, and a second bevel gear mounted to the body.
10 . The door lock of claim 1 , further comprising:
a position gear that is coupled to the reverse drive gear, the position gear having mounted thereon a position sensor;
wherein the forward drive gear and the reverse drive gear are arranged such that:
when the drive motor is driven in a locking direction, the clutch gear moves toward and engages with the forward drive gear, and
when the drive motor is driven in an unlocking direction, the clutch gear moves toward and engages with the reverse drive gear.
11 . The door lock of claim 1 , further comprising a tailpiece receiver coupled with the thumb turn and adapted to receive a tailpiece of a pre-existing lock distinct from the door lock.
12 . The door lock of claim 11 , wherein:
responsive to the clutch gear being coupled with the lock drive, operation of the drive motor to rotate the clutch gear causes the tailpiece receiver to operate, via the tailpiece, the pre-existing lock; and
responsive to the clutch gear not being coupled with the lock drive, movement of the tailpiece receiver does not rotate the clutch gear.
13 . A door lock comprising:
a body adapted to be mounted to a door and having a base, wherein the base has a curved slot formed therein;
a lock drive movably mounted to the base of the body and adapted to move a lock mechanism between locked and unlocked positions;
a thumb turn movably mounted to the body and adapted for manual movement between at least two positions, the thumb turn being coupled to the lock drive such that movement of the thumb turn moves the lock drive;
a drive motor mounted to the base of the body; and
a clutch that is mechanically arranged between the drive motor and the lock drive, the clutch including
a forward drive gear and a reverse drive gear that are both mounted to the base of the body and coupled to the lock drive, and
a clutch gear having a pivot axis, the clutch gear being mounted in the curved slot of the base, wherein:
the clutch gear is configured for displacement along the curved slot between an engaged position in which the clutch gear is coupled with the lock drive and a disengaged position in which the clutch gear is not coupled with the lock drive,
the clutch gear is configured for rotation about the pivot axis,
the clutch gear is operably coupled with the drive motor such that movement of the drive motor effects rotation of the clutch gear about the pivot axis, and
the rotation of the clutch gear about the pivot axis effects displacement of the clutch gear along the curved slot to selectively couple and uncouple the drive motor to the forward drive gear and the reverse drive gear,
wherein the curved slot has a position where positioning the pivot axis of the clutch gear causes the clutch gear to engage with the reverse drive gear, and
wherein energizing the drive motor for a predetermined interval of time displaces the clutch gear between the engaged position and the disengaged position.
14 . The door lock of claim 13 , wherein the engaged position is either of:
a first engaged position, in which the clutch gear is engaged with the forward drive gear, or
a second engaged position in which the clutch gear is engaged with the reverse drive gear.
15 . The door lock of claim 14 , wherein the first engaged position is a forward engaged position such that rotation of the forward drive gear rotates the lock drive in a forward direction, and the second engaged position is a rearward engaged position such that rotation of the reverse drive gear rotates the lock drive in a reverse direction.
16 . The door lock of claim 15 , wherein the disengaged position is located on the curved slot between the forward engaged position and the rearward engaged position.
17 . The door lock of claim 16 , wherein rotation of the drive motor in a first direction displaces the clutch gear along the curved slot toward the forward engaged position, and rotation of the drive motor in a second direction displaces the clutch gear along the curved slot toward the rearward engaged position.
18 . The door lock of claim 13 , wherein the lock drive includes a drive wheel mounted to the body that is coupled to the forward and reverse drive gears.
19 . The door lock of claim 18 , wherein the thumb turn is coupled for movement with the drive wheel such that movement of the thumb turn moves the drive wheel, and movement of the drive wheel moves the thumb turn.
20 . The door lock of claim 19 , wherein rotation of the drive motor in a first direction causes the clutch gear to be displaced along the curved slot by reaction forces arising from interactions between the clutch gear, the forward drive gear and the curved slot.
21 . A method of operating a door lock, the method comprising:
receiving, via a wireless communication device, a command to control a door lock having a lock drive that is configured to move a lock mechanism between a locked position and an unlocked position;
after receiving the command, controlling a drive motor that is coupled to the lock drive via a clutch gear that selectively engages with either a reverse drive gear used to move the lock mechanism to the unlocked position or a forward drive gear used to move the lock mechanism to the locked position, wherein the drive motor operates in a first direction for a first period of time that is sufficient to (a) displace the clutch gear to a first position where torque is transmitted to the lock drive via the clutch gear and either the reverse drive gear or the forward drive gear, and (b) move the lock mechanism between the locked position and the unlocked position;
detecting a position of the lock drive using a position sensor that is mounted to a position gear that is coupled to the reverse drive gear;
after moving the lock mechanism between the locked position and the unlocked position, and in response to detecting that the lock drive is positioned such that the lock mechanism in the locked position or the unlocked position, controlling the drive motor to (a) operate in a second direction that is opposite the first direction, and (b) move the clutch gear so as to decouple the drive motor from the lock drive; and
in response to detecting that the clutch gear has disengaged from the forward drive gear, deactivating the drive motor.
22 . The method of claim 21 , wherein operating the drive motor in the first direction causes the lock mechanism to move to the unlocked position.