CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application 62/344,411 filed on 02 June 2016, which is incorporated herein by reference.

TECHNICAL FIELD

[0002] The invention relates to locks for furniture's doors and drawers and more specifically it relates to remotely controlled locking system for plurality of cabinet doors and/or drawers.

BACKGROUND ART

[0003] Cabinet's doors and drawers often contain objects access to which have to be controlled. Within household kitchen, cabinets and drawers may contain hazardous detergents, knives, glassware etc. For child safety, these cabinets and drawers have to be secured against access by children.

[0004] Many types of childproof access devices have been developed. One type is manually operated spring loaded latch for each cabinet door or drawer, such as described in US patents 4,139,249, 5,795,044, and 5,823,649. However, these devices engage whenever the cabinet door or drawer is closed, and each time access is required, the device have to be unlatched. Unlatching requires the use of two hands since the device is installed in the cabinet or drawer.

[0005] US patent 6,431,616 discloses a spring loaded lock that can be opened with one hand by firmly pushing a button. In this case the lock is engaged when the door or drawer are closed, thus it is inconvenient for frequent access, such as kitchen cabinets or drawers.

[0006] US patent 5,188,405 discloses a magnetic operated latch that can be engaged only when required, thus alleviating the inconvenience of automatic closure of the door or drawer. In the closed state, a magnet holds the door closed. Thus, force must be applied in order to open the door.

[0007] US patent 5,360,243 discloses a spring loaded electromagnetically unlocking device. To open the door or drawer one must push the disengagement button that activates the electromagnet and open the door. This type of mechanism enables opening of one door or drawer at a time. The lock is automatically engaged when the door or drawer are closed, and there is a need to activate the unlock mechanism for each access.

[0008] US publication 20030205953 discloses an electromagnetic lock that is activated in order to hold the door or drawer closed. Multiple doors and drawers can be controlled simultaneously by a central control unit, which can be remotely controlled. The drawback of this approach is that current continuously flows in the system. The current is a function of the number of locks that are engaged. Because most of the time the cabinets and the drawers are kept closed, high power is consumed by the system, so that the mechanisms may be heated up and may pose a safety issue.

[0009] US publication 20070051598 discloses a child safety lock system using electromagnet where each lock can be operated either locally or by a remote controller that can control multiple locks. In this solution, the actuated locks require constant power supply.

[0010] Korean publication KR20080084202 discloses an electronic locking apparatus for locking multistage drawers. A key lever moves up or down by a motor that includes an encoder for providing feedback on the position of the motor's axis. The controller to position the motor axis in the desired angle uses data from the encoder. This solution is appropriate for multistage drawer cabinets, where one motor locks simultaneously multiple drawers. This solution is limited to drawer cabinets but it does not support locking of cabinet doors.

[0011] Korean publication KR100740427 discloses a power efficient locking device that is comprised of a motor and a spring, both connected to a cam. Normally the spring holds the cam in the locked position, whereas the geared motor rotates it to the open position. When power to the motor is stopped, the spring rotates the cam to the closed position. In order to keep the locks in open state current has to be supplied continuously, this is a waste of energy, where the locks have to remain in unlocked state for long periods of time, such as in a kitchen. SUMMARY OF INVENTION

[0012] The invention discloses a centralized locking system for cabinet doors and drawers for preventing access from unauthorized persons. The system is comprised of plurality of servomotor driven locks controlled by PWM signals which consumes energy only during state transition, plurality of holding hooks, controller unit capable of generating plurality of PWM servomotor control signals in response to external wired and/or wireless command, and remote control unit.

[0013] It is the object of the invention to provide user friendly system that allows all doors and drawers, or a selected subset to be simultaneously controlled. It can be controlled either locally or by a remote controller.

[0014] It is another object to provide a locking system that can be neatly integrated into the furniture, be it at home or in the office. The system operates on low voltage supply and requires energy only during state transition. It has a backup battery that enables independence of operation from mains supply.

BRIEF DESCRIPTION OF DRAWINGS

[0015] FIG. 1 shows schematic diagram of the invented lock.

[0016] FIG. 2 presents the signals for opening and closing a lock.

[0017] FIG. 3 shows signals for controlling multiple locks simultaneously.

[0018] FIG. 4 shows a typical structure of a lock according to the present invention.

[0019] FIG. 5 presents a lock in closed state.

[0020] FIG. 6 presents a lock in open state.

[0021] FIG. 7 presents typical structure of holding hook.

[0022] FIG. 8 shows assembly of lock and holder hook on doors.

[0023] FIG. 9 presents preferred embodiment of locking system.

[0024] FIG. 10 presents embodiment of locking arrangement for drawer cabinet. DETAILED DESCRIPTION

[0025] Full description of the invention is given hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the invention is shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiment set forth herein; rather this embodiment is provided so that the disclosure will be thorough, and will fully convey the scope of the invention to those skilled in the art.

[0026] It is the object of the present invention to provide a flexible, safe, easy to use cabinet's doors and drawers locking system. It enables easy access to selected cabinet's doors and drawers when required, and denies access otherwise.

[0027] FIG. 1 shows a schematic diagram of the invented lock 100. The lock is comprised of a servo motor unit 110, which drives the dead bolt 120 via axis 118. The servo unit 110 is comprised of a dc motor 114 with angular sensor, gear 112, and electronics servo controller 116. The lock is connected to two power supply lines 122 and to control signal line 124, which receives PWM waveform. The voltage for the operation of the lock is a low level DC voltage, in the order of 6 volts.

[0028] FIG. 2 shows the shape of the control signals that drive that lock. Waveform 210 shows a typical close signal whereas waveform 220 shows a typical open signal. Tl, the close signal width is 0.9 milliseconds, and it has to be repeated every 20 milliseconds - the period of the signal TO. This waveform has to be applied for more than 500 milliseconds to assure that the lock is positioned in the desired closed state. T2, the open signal lasts for 1.8 milliseconds having the same repetition rate as Tl, i.e. 20 milliseconds, and have to be applied for more than 500 milliseconds to assure proper lock opening.

[0029] The initial current consumed by a motor is high. Thus, when multiple motors are activated simultaneously the peak current equals to the sum of the peak current for each motor. When using a servomotor for driving the dead bolt, the control signal to the servomotors can be phase shifted, as demonstrated in FIG. 3, so that the peak current equals to the peak current of a single motor. This leads to a more efficient and safe power supply requirement. Close control signals 310, 320, and 330 are simultaneously applied to four different locks or lock groups, hence keeping the peak current at a low level. [0030] FIG. 4 shows a preferred structure of a lock according to the present invention. The lock mechanism, comprised of the servomotor unit 110 and dead bolt 120, is mounted within a small depth cylinder 410 to which two fastening flaps 420 are attached. FIG. 5 shows the lock 510 in closed state, where the dead bold 120 is extended out of the lock housing. FIG. 6 shows the lock 510 in open state where the dead bolt 120 is within the lock housing.

[0031] FIG. 7 presents typical structure of holding hook 710. The lock is always mounted on the fixed frame of the cabinet whereas the holding hooks are attached to the moving elements be it a door or a drawer. Holding hook is comprised of a rosette 712, which is attached to the door or drawer, and a hook 714 mounted on the rosette. A tuning screw 716 enables to move the hook relative to the rosette so the hook is positioned in the desired location to assure proper closure of the door or drawer.

[0032] FIG. 8 shows assembly of lock and holder hook on doors. The locks 510 are mounted in the fixed frame 820. The holding hooks 710 are attached to the doors 830. The locks are shown in the closed state.

[0033] A preferred embodiment of a locking system is shown in FIG 9. The locking system is comprised of plurality of locks 910, wiring panel 920, and central control unit 930. The locks 910 are properly mounted on cabinet frames, and compatible holding hooks attached to the doors or drawers. In the wiring panel 920 there are plurality of lock plugs PI to PN, to which the wires from the locks are connected. Each plug carries the voltage supplied to the lock and the PWM control signal. The wiring panel 920 is also electrically connected to the central control unit 930 from which it receives the power supply for the locks (terminals +v and -v) and four lock PWM control signals. Within the wiring panel 920, the power supply is connected to all the lock plugs. The four PWM signals can be connected so to form up to six groups of locks that can be activated or released by the same command given to the central control unit.

[0034] The Central Control Unit 930 can get commands for the closing or opening of up to four groups of locks either by RF link from a remote switch 940 or from a logic input from external source via the LI/O terminal 950. Through this terminal, it can provide logic information on the status of the locks. The Central Control Unit is comprised of a power supply unit, RF receiver, battery backup and microcontroller. It is to be understood that the system can be built in many other architectures, all of which use the PWM activated locks. [0035] An example of installation of the locks in drawer cabinet is presented in FIG 10. The front of the drawer cabinet 1000 is marked by 1010 and the back of the drawer cabinet is pointed to by 1020. A post 1030 on which the locks 1040 are mounted is firmly attached to the inside frame of the cabinet on its backside. A separate lock is installed for each drawer. A holding hook 1042 is firmly attached to the back panel 1022 of each drawer.

[0036] It is obvious to one skilled in the art that the described system can easily be integrated into clever home systems and it can be controlled by applications running on cellular telephones.