The present invention relates to an electronic lock, and more particularly to an electronic lock including a compression spring that stores energy to ensure that the electronic lock relocks after unlocking.
Door locks in hotels often use electronic key cards rather than normal mechanical keys to control lock operation. Electronic key cards and electronic locks are easily programmable and therefore provide added security in a convenient manner.
When a currently-known electronic lock is locked, a lock bolt is received in a notch in a rotatable portion connected to an outside handle, preventing the rotatable portion, and therefore the outside handle, from being rotated to open a door and access a room. When a person wants to enter the room, the electronic key card is inserted into a slot in the electronic lock. If a card reader in the electronic lock identifies the electronic key card, a motor removes the lock bolt from the notch in the rotatable portion, allowing the rotatable portion and the outside handle to be rotated to open the door.
After a predetermined amount of time, the motor reverses to re-insert the lock bolt into the notch of the locking portion to prevent the outside handle from being actuated. However, if the outside handle has not been released and the locking portion has not returned to the original position, the lock bolt cannot re-enter the notch of the rotatable portion. When the outside handle is finally released and the locking portion returns to the original position, it is possible that the lock bolt might not re-enter the notch in the locking portion, possibly preventing the electronic lock from relocking.
Another drawback to known electronic locks is that a different lock is required for a door needing a lock with handles having a right-hand configuration and a door needing a lock with handles having a left-hand configuration. Therefore, two different types of locks need to be manufactured.
There is therefore a need in the art for an electronic lock that ensures that the electronic lock relocks after a handle is actuated to enter a room and that can be mounted in either a left-hand configuration or right-hand configuration.
A door includes an inside handle, an outside handle, and an electronic lock. When the electronic lock is locked, the outside handle cannot be actuated, preventing access to a room. The electronic lock includes a locking portion attached to the outside handle and a mounting portion attached to the inside handle.
The electronic lock includes a compression spring that stores energy to ensure that the electronic lock is re-locked after the electronic lock is unlocked. The compression spring is received in a lock bolt and a lock bolt housing.
When the electronic lock is locked, the lock bolt is received in a notch of the locking portion, preventing rotation of the locking portion and therefore actuation of the outdoor handle. When an electronic key card is inserted into the electronic lock and identified by a card reader, a motor moves the lock bolt and the lock bolt housing in a direction to remove the lock bolt from the notch in the locking portion. The locking portion and the outside handle can then be rotated, allowing the door to be opened to access the room.
After a predetermined amount of time, the motor is actuated in a reverse direction to move the lock bolt housing in an opposing direction. If the outside handle has not yet been released, the notch of the locking portion does not align with the lock bolt, preventing the lock bolt from re-entering the notch. The lock bolt does not move with the lock bolt housing in the opposing direction, and the compression spring is compressed between the lock bolt housing and the lock bolt to store energy.
After the outside handle is released, the locking portion returns to the original position, and the notch of the locking portion aligns with the lock bolt. The energy stored in the compression spring pushes the lock bolt to enter the notch, ensuring that the electronic lock is locked after the outside handle is released.
The electronic lock can be mounted in either a right-hand configuration or a left-hand configuration. The locking portion includes a raised arched portion, and the mounting portion includes an arched recess including a raised arched portion. The mounting portion can be rotated 180° to change the electronic lock between configurations. In either configuration, when the inside handle is rotated, the inside handle rotates the mounting portion to open the door. When the outside handle is rotated, the outside handle rotates the locking portion, and the raised arched portion of the locking portion engages the raised arched portion of the mounting portion to rotate both the locking portion and the mounting portion to open the door.
When a person wants to enter the room, an electronic key card 28 is inserted into a slot 30 in a housing 32 of the electronic lock 20. If a card reader (not shown) positively identifies the electronic key card 28, the electronic lock 20 is unlocked, allowing the outside handle 24 to be actuated. As either the inside handle 22 or the outside handle 24 is actuated, a tab 118 in the door 26 is removed from an opening (not shown) in the door trim (not shown), allowing the door 26 to be opened.
The electronic lock 20 may include indicator lights 35a, 35b and 35c. When the electronic key card 28 is incorrectly inserted in the slot 30 or if the electronic key card 28 is not programmed to unlock the electronic lock 20, the light 35a displays red. If the electronic lock 20 malfunctions, the light 35b displays yellow. If the electronic key card 28 is identified, the light 35c displays green, and the outside handle 24 can be actuated to open the door 26 and access to the room. Of course, other illumination structures and schemes may be implemented without departing from the scope of the invention.
A portion of the lock bolt 38 is received in a recess 50 of a lock bolt housing 52 (further shown in
The lock bolt housing 52 also includes a slot 58 that allows the lock bolt 38 to slide relative to the lock bolt housing 52. When the lock bolt 38 slides relative to the lock bolt housing 52, the compression spring 48 is compressed between the edge 44 of the recess 42 of the lock bolt 38 and the edge 56 of the recess 50 of the lock bolt housing 52. In one example, the lock bolt housing 52 is made of plastic. However, it is to be understood that the lock bolt housing 52 can be made of other materials, and one skilled in the art would know what materials to use.
When the card reader identifies the electronic key card 28, a motor 60 powered by a battery pack (not shown) is activated to unlock the electronic lock 20. A circular cam surface 62 is attached to the motor 60 by an off-center post 64. That is, the off-center post 64 is not aligned with a central axis of the circular cam surface 62. When the motor 60 is actuated, the motor 60 turns the off-center post 64 to rotate the circular cam surface 62. The off-center post 64 is not aligned with the central axis of the circular cam surface 62, and therefore the circular cam surface 62 produces a camming effect. As shown in
A plate 68 retains the motor 60 in the housing 32 (further shown in
The electronic lock 20 further includes a rotatable locking portion 74 including a stem 76. The stem 76 is received in an opening 79 in the outside handle 24, and movement of the outside handle 24 rotates the locking portion 74. The locking portion 74 includes a notch 78 on an outer circumference of the locking portion 74. The locking portion 74 also includes a circular portion 80 concentric with the stem 76 and an arched portion 82 raised from the circular portion 80. The locking portion 74 also includes a flange 113 that prevents over-rotation of the locking portion 74, as explained below.
The electronic lock 20 further includes a mounting portion 84 having a stem 86. The stem 86 of the mounting portion 84 is inserted into an opening (not shown) in the inside handle 22, and movement of the inside handle 22 rotates the mountable portion 84.
A circular spring 90 including two arms 92 is received around the locking portion 74. When the electronic lock 20 is assembled, the flange 113 is received between the two arms 92 of the circular spring 90. The two arms 92 prevent over-rotation of the locking portion 74 as the outside handle 24 is actuated.
The components of the electronic lock 20 are retained in the housing 32 by a closing plate 94. Fasteners 98 received in aligned holes 100 in the closing plate 94 and holes 102 in the housing 32 secure the closing plate 94 to the housing 32. Preferably, four fasteners 98 secure the closing plate 94 to the housing 32. In one example, the fasteners 98 are screws. However, it is to be understood that the other fasteners can be employed, and one skilled in the art would know what type of fasteners to employ. Two fasteners (not shown), such as screws, pass through the two holes 106 in the closing plate 94 to further secure the housing 32 to the door 26.
When the components are retained in the housing 32, the stem 86 of the mounting portion 84 extends through an opening 104 in the closing plate 94, and the inside handle 22 can then be attached to the stem 86 of the mounting portion 84.
When assembled, a bushing 108 is located between the opening 104 in the closing plate 94 and the mounting portion 84 to prevent wear. A bushing 110 is located between the housing 32 and the locking portion 74 to prevent wear, and a bushing 112 is located between the locking portion 74 and the mounting portion 84 to prevent wear.
After a predetermined amount of time, the motor 60 is reversed to move the lock bolt housing 52 in an opposing direction as shown in
It is also possible to employ an electronic key card 28 that unlocks the electronic lock 20 and does not reverse the motor 60 until the electronic key card 28 is reinserted. In this example, the motor 60 does not reverse after the predetermined amount of time.
The electronic lock 20 can be changed from the left-hand configuration to the right-hand configuration by removing and rotating the mounting portion 84 relative to the locking portion 74. As shown in
The foregoing description is only exemplary of the principles of the invention. Many modifications and variations of the present invention are possible in light of the above teachings. The preferred embodiments of this invention have been disclosed, however, so that one of ordinary skill in the art would recognize that certain modifications would come within the scope of this invention. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.