The present invention relates generally to drawer slides, and more particularly to drawer slides with locking mechanisms.
Drawer slides are often used to extendably couple drawers within cabinets or racks within frames. Using a cabinet application as an example, drawer slides generally have one member mounted to a drawer and another member mounted to a cabinet. The two members are extendably coupled together, often by way of ball bearings, so that the extension of the drawer slide provides for extension of the drawer from the cabinet, allowing for easy access to the contents of the drawer.
Unfortunately, uncontrolled easy access to contents of a drawer is not always desired. A drawer may contain items of a personal nature, or, as may often be the case in a commercial setting, the drawer may contain valuable items. Secure storage of such items may be an important consideration, and drawer slides, with the ease of access they provide, may not be an appropriate.
More secure storage, for example as provided by a safe or a lock box, may also not always be appropriate. At times frequent and repeated access to stowed items may be required, albeit in a controlled manner. Moreover, structures associated with safes and lock boxes may be somewhat bulky, and not easily incorporated in a cabinet type structure which otherwise may be desired.
Aspects of the invention provide a drawer slide and electronically actuated lock mechanism.
One aspect of the invention provides an assembly including a lock mechanism, comprising: a housing for mounting within a cabinet; a latch receiver rotatably mounted at least partially within the housing; a lever arm rotatably mounted at least partially within the housing, the lever arm rotatable between a locked position, in which the lever arm blocks rotation of the latch receiver in a first direction, and a position in which the lever arm does not block rotation of the latch receiver in the first direction; an electrically actuated actuator mounted at least partially within the housing, the electrically actuated actuator drivably coupled to the lever arm to rotate the lever arm in at least one direction; and a first switch, with status of the first switch indicating whether the lever arm is in the locked position.
Another aspect of the invention provides a lock assembly, comprising: a housing for mounting within a cabinet; a latch receiver rotatably mounted at least partially within the housing, the latch receiver rotatable between an open position and a closed position; a lever arm rotatably mounted at least partially within the housing, the lever arm rotatable between a locked position, in which the lever arm blocks rotation of the latch receiver in a first direction, and a position in which the lever arm does not block rotation of the latch receiver in the first direction; an electrically actuated actuator mounted at least partially within the housing, the electrically actuated actuator drivably coupled to the lever arm to rotate the lever arm in at least one direction; and a microprocessor within the housing, the microprocessor configured to command operation of the electrically actuated actuator to drive the lever arm from the locking position.
Another aspect of the invention provides an assembly including a lock mechanism, comprising: a latch receiver rotatably mounted at least partially within the housing; a lever arm rotatably mounted at least partially within the housing, the lever arm rotatable between a locked position, in which the lever arm blocks rotation of the latch receiver in a first direction, and a position in which the lever arm does not block rotation of the latch receiver in the first direction; an electrically actuated actuator mounted at least partially within the housing, the electrically actuated actuator drivably coupled to the lever arm to rotate the lever arm in at least one direction; a first switch operated by the latch receiver, with status of the first switch indicating whether the locking arm is in the locked position; and an undermount drawer slide including a pin for engagement with the latch receiver.
These and other aspects of the invention are more fully comprehended upon review of this disclosure.
The lock mechanism includes a latch receiver 115. The latch receiver receives the latch arm when the drawer slide is in or approximate a closed position. The latch receiver is maintained in locked position by a lever arm 117, which is moveable between a locking position and an unlocking position by activation of a motor 119. In some embodiments the latch receiver is maintained in the locked position by engagement with a top of the lever arm. In some embodiments, for example as illustrated in
As illustrated in the embodiment of
The three drawer slide members, which are slidably or rollably coupled by way of ball bearings in many embodiments, are arranged with the intermediate slide member nested within the outer slide member, and the inner slide member in turn nested within the intermediate slide member. When mounted to a cabinet and a drawer, with the slide in the closed position the intermediate slide member and the inner slide member are substantially within the volume of the outer slide member.
In the embodiment illustrated in
The pin may be welded or otherwise attached to the extension of the inner slide member, for example by riveting, with the pin being a rivet. In other embodiments the pin may be formed of the material of the inner slide member, and may for example be in the form of a post or other form punched or pressed from the material of the inner slide member.
The lock mechanism includes components configured to work in combination to capture the pin within the latch receiver and secure the inner slide member in the closed or locked position. Conversely, the components of the lock mechanism may also be activated to release the pin from the latch receiver and thus, release the inner slide member to allow it to return to the open position. The latch receiver captures the pin, such that the pin, and therefore the inner slide member, is prevented from moving to an open position. Thus, the pin may be considered a latch arm, and the pin and the latch receiver may together be considered a latch.
An automated open-assist mechanism 105 is provided within the housing to provide an open-assist feature for the drawer slide and drawer. In one embodiment, the open-assist mechanism is positioned in the housing so as to engage a portion of a drawer slide assembly, for example an intermediate slide member. The open-assist mechanism includes a spring housing which incorporates a plunger coupled to a biasing member, such as a spring. Operationally, in one embodiment, upon closing of the drawer slides, the plunger is contacted by the intermediate slide member, which causes the plunger to compress the biasing member within the housing. The biasing member therefore biases the intermediate slide member forward while the inner slide member is locked in position. When the latch receiver moves to the unlocked position, however, the bias provided by the biasing member pushes the intermediate slide member via the plunger, forward, carrying the inner slide member and drawer forward to at least a slightly open position. In some embodiments, however, functions of the open-assist mechanism may be provided by a spring, discussed below, which normally biases the latch receiver to the open position.
As shown in the embodiment illustrated in
In the embodiment of
A bumper 236 is positioned to engage the third leg 230 of the latch receiver when the latch receiver is in the open position. Preferably the bumper includes a soft compliant shell, for example of rubber, to reduce noise generated by contact of the third leg and the bumper. The bumper is positioned such that its engagement with the third leg counters the bias from the first spring to cause the latch receiver to stop rotating as the basin is positioned to receive the pin. The constant biasing of the latch receiver by the first spring and the counteraction of this bias by the third leg against the bumper ensures that the latch receiver is held in place and does not inadvertently move out of position.
With reference also to
Referring again to
The lever arm is substantially flat and generally of rectangular shape. A hole 224 is defined on the lever arm at approximately a third of the length from a top edge 246 of the lever arm, for insertion of a pin or rivet for mounting to the housing base. The pin or rivet provides a fulcrum for the lever arm upon which to rotate. A cam follower 248 is formed at the opposite end from the top edge of the lever arm and is configured to engage with the motor cam.
The lever arm is biased to a ready or “locking” position shown in
The motor cam operationally engages the cam follower to rotate the lever arm to an open position, with the top edge of the lever arm being moved away from a locking engagement with the third leg of the latch receiver. The motor cam is operationally coupled to motor such that rotation of the motor causes the motor cam to push against the cam follower to overcome the spring force provided by the second spring and the third spring, and rotate the lever arm such that the third leg of the latch receiver clears the top of the lever arm.
The motor 240 is powered via electric wiring 256. Power may be supplied to the motor by or through batteries, or power outlets commonly found in residential or commercial settings, with the power supplied by a utility or back-up generator or the like. The motor may be any motor with sufficient torque capability to overcome spring or other forces to rotate the lever arm when desired. For example, the motor may be a gear motor, stepper motor and the like.
Generally, the motor is activated when desired with the use of a button, switch or similar device. In some embodiments drive circuitry for the motor may be provided, which may be activated by entry of a password or identification number by way of a keypad, by a signal, preferably encoded, from a wireless transmitter, or by some other way of receipt of a signal, preferably coded, indicating authorized opening of the drawer is requested.
Accordingly, as the inner slide member is moved towards the closed position the pin reaches the basin of the latch receiver. As the user continues to slide the drawer closed, the pin is forced against a second leg 330 of the generally U-shaped latch receiver, which is in the travel path of the pin. The force of the pin against the second leg overcomes the bias of the first spring 326 to rotate the latch receiver from the open or unlocking position to the closed or locking position shown in
Rotation of the latch receiver causes a third leg 306 of the latch receiver to also rotate away from the bumper. As shown in
As shown in
Upon activation of the motor, for example, by the depression of a button, the throwing of a switch, after drive circuitry receives a coded signal, or through other activation means, the latch receiver is returned to its open position. Activation of the motor rotates a motor cam 334. The engagement between the surface of the motor cam and the surface of a cam follower 336 of the lever arm is done with sufficient force to overcome the bias of the second spring and any friction between the top edge of the lever arm and the bottom edge of the third leg to rotate the lever arm about its pivot point. The rotation of the lever arm moves the top edge of the lever arm out of the travel path of the third leg of the latch receiver. With the third leg free from contact with the lever arm, the first spring biases the latch receiver to the unlocking position, swinging the third leg along its travel path until the third leg once again engages with a bumper 338 to stop the rotation. The pin, and therefore the inner slide member and drawer, are free to move to a forward extended position.
Forward movement of the pin is assisted by a compression spring (not shown) in a housing 340. The compression spring has an end coupled to a plunger, which bears against an intermediate slide member of the drawer slide assembly. As the drawer slide is closed, the intermediate slide member, via the shaft, compresses the compression spring. Once the latch receiver releases the pin, the compression spring provides an open-assist force pushing the intermediate slide member, and therefore the inner slide member and drawer, towards an open position.
The motor is commanded to operate by a microprocessor 537 mounted on a circuit board 535. The circuit board fits within a profile of an insulating sleeve, which is installed onto a base holding the locking mechanism. The insulating sleeve electrically insulates the circuit board and microprocessor from, for example, metal components of the locking assembly, as well as providing some protection from spurious debris that may enter the lock mechanism or otherwise be generated during use of the lock mechanism.
The microprocessor may, in various embodiments, take the form of a microprocessor, a digital signal processor (DSP), an FPGA, or a custom or semi-custom ASIC. The microprocessor receives signals to lock or unlock the assembly from an external device, for example an access controller. In some embodiments the access controller, which may be used to externally command locking or unlocking of a drawer mounted to the drawer slide, provides a first voltage signal, for example by applying a positive voltage signal, or a negative voltage signal, to command an unlocked state for the assembly, and removes the first voltage to command a locked state. Such a configuration of signals may allow for increased drawer security, or security of other receptacle locked by the locking mechanism, in the event of absence of signals from the access controller, for example in the event of loss of power to the access controller or interruption of signal paths between the microprocessor and access controller.
In various embodiments the microprocessor includes a power converter to accept a wide range of input voltages and provide, when enabled, a generally constant voltage in absolute terms, with the output switchable between a positive relatively constant voltage or a negative relatively constant voltage. The availability of the switchable complementary output, when on or enabled, allows for use of a single wide range voltage input to drive the motor in either of two directions. In some embodiments the microprocessor, or other circuitry on the circuit board, accepts, for example, an input voltage approximate a 5V-30V range, and provides as an output a voltage of about ±5V. In some embodiments a first power converter is used to translate an input voltage in the 5V-30V range to a 5V voltage, and a second power converter is used to switchably convert voltages supplied to the motor to −5V, 0V, or 5V, for example as commanded by the microprocessor.
In some embodiments the microprocessor commands the motor to effectively drive the lever arm from a locked position to an unlocked position by driving the motor in a first direction for a predetermined period of time, or through a predetermined number of steps, for example for a stepper motor. Similarly, the microprocessor may command the motor to effectively drive the lever arm from the unlocked position to the locked position by driving the motor in a second direction, opposite the first direction, for a predetermined period of time, or through a predetermined number of steps. In this regard, the presence of cam stops, for example provided by the protrusions on the cam, provide positive known stop positions for the cam, and the motor, in the locked and unlocked positions, increasing reliability of operations over time.
A forward end of the latch receiver further includes, when compared to the latch receiver of prior embodiments, an extending base surface forming a flange 529, which may also be seen in
Similarly, a second switch 531 is positioned to be contacted by a protrusion of the cam 525 when the cam is positioned to place the locking arm 523 in the locking position, with the second switch placed into a closed state when the cam is positioned to place the locking arm in the locking position.
In some embodiments status of the switches is provided to the microprocessor. In some embodiments status of the switches is provided to some other unit, for example an access controller. Provision of the status of the switches to the microprocessor is convenient in that it allows for the microprocessor to determine if the drawer slide is open or closed, or if the locking arm is in a locking position. The microprocessor may provide this information, namely lock/unlock status of the locking mechanism and/or open/close status of the drawer, to another unit, for example an access controller, to memory, and/or to visual display devices, such as light sources. Such use of the information allows the microprocessor or the access controller to retain the information for maintenance of access records for example, or to provide visual presentation, for example by way of illumination of light sources, of drawer and lock mechanism status.
In some embodiments the switches are subminiature snap action type switches. The switches include a lever arm which is spring loaded, with position of the lever arm determining switch status. The body of the switch may be molded using a plastic material. Preferably a body of the first switch includes two holes for snapping over two corresponding posts positioned on the lock base. The posts of the lock base and the holes are preferably designed to provide an interference fit, allowing for a fastening of the switch to the assembly without the use of additional fasteners or bonding material. Preferably, the posts and the holes are sufficiently precisely located for uniform operation of the switch with respect to the latch arm receiver. Similarly, a body of the second switch may include a hole configured for an interference fit with a post of the lock base (or the insulator sleeve in some embodiments) and, in some embodiments a straight ledge of the body aligned with a corresponding straight ledge of the insulator sleeve.
As illustrated in
The lock mechanism of
In operation, as the inner slide member moves to a closed position, the pin (not shown) on the inner slide member contacts the basin of the latch receiver, and begins to move the latch receiver towards the closed position. As the latch receiver reaches the closed position, and the leg of the latch receiver contacts the leaf spring, the contact provides a detent in the closed position. The slide member may thereafter be opened, through provision of force, such as provided by pulling on a drawer coupled to the inner slide member. Without provision of force, however, the inner slide member, and therefore the drawer coupled to the drawer slide, will remain in the closed position.
In addition, the lock mechanism also includes opposing posts 717a,b positioned forward of the latch receiver. The posts are positioned so as to be about either side of a tab 730 extending from the inner slide member when the inner slide member is in the closed position. The opposing posts each include a lip at their ends, with the lips facing one another and therefore facing towards a longitudinal centerline of the inner slide member. A protrusion 719 extends from the side of the tab. When the inner slide member is in the closed position, the protrusion is adjacent the post, and the lip of that post constrains movement of the protrusion, and therefore the inner slide member, in a direction away from the other slide members. Such a constraint is beneficial in that the pin is also more securely held in the basin of the latch receiver when the inner slide member is in the closed position. Of course, from the foregoing, it should be apparent that in some embodiments only a single post is used. The use of dual posts, however, allows for a reversely mounted inner slide member, or in other words an unhanded mechanism. In addition, in some embodiments two protrusions on the inner slide member may be used, with the protrusions in opposite sides of the tab, providing for increased constraint for the inner slide member.
The latch receiver has a basin formed between a jaw 813 of the latch receiver and an opposing tooth 815. The latch receiver, in operation, is contacted by a latch, which when closed forces the latch receiver to rotate to a closed position.
As may be seen in
The cam also includes cam stops, in the form of protrusions on the cam. The camming stops prevent over rotation of the cam, and the motor spindle, allowing for increased regularity in positioning of the cam during operation and over time. A first cam stop 1124 stops rotation of the cam in the camming position, with the camming surface 1123 displacing the lever arm to the unlocked position. The first cam stop stops rotation of the cam by contact with a base plate 1126, with the base plate preventing further rotation of the cam past the camming position. Similarly, a second cam stop 1122 stops rotation of the cam in the uncamming position, with the camming surface 1123 away from the lever arm. As with the first cam stop, the second cam stop stops further rotation of the cam by contact with the base plate. In some embodiments a base plate is not used, with for example functions of the base plate provided by the base 1112. However, in various embodiments the base 1112 (and its corresponding cover (not shown in
Each of the drawer slides 1215a-d includes a corresponding lock mechanism 1217a-d, with each lock mechanism shown about the rear of a corresponding drawer slide. In some embodiments multiple or all drawer slides for a particular drawer may be equipped with a lock mechanism, in other embodiments only a single drawer slide may be equipped with a lock mechanism. The lock mechanism may be, for example, as discussed with respect to
Each of the lock mechanisms is electrically coupled to control circuitry 1225. The control circuitry, which in some embodiments may be the access controller discussed with respect to
In the embodiment shown in
The control circuitry and the receiver are powered by AC utility power or generator power in some embodiments, generally converted to DC power by power conversion circuitry, which may be provided by a power supply unit. In other embodiments the control circuitry and receiver are powered by battery power. In some embodiments AC utility power or generator power may be a primary source of power, with battery power provided as a backup source of power in the event of failure of the primary source of power.
Accordingly, the invention provides a drawer slide, a locking mechanism, and a drawer slide with a locking mechanism. Although the invention has been described with respect to specific embodiments, it should be recognized that the invention comprises the novel and unobvious claims supported by this disclosure, along with their insubstantial variations.
This application claims the benefit of the filing date of U.S. Provisional Patent Application No. 61/673,159, filed Jul. 18, 2012, the disclosure of which is incorporated by reference herein.
Number | Date | Country | |
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61673159 | Jul 2012 | US |
Number | Date | Country | |
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Parent | 13945831 | Jul 2013 | US |
Child | 15670702 | US |