DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Referring now to the accompanying drawings and initially to FIG. 1, a cabinet according to a preferred embodiment of the invention is shown generally at 100. With the exception of the locking mechanism and the locking barrier (as described in detail below), the cabinet 100 of the preferred embodiment is substantially similar to the cabinets disclosed in U.S. Pat. Nos. 5,069,511, 5,205,628, and 5,314,244, all of which are incorporated herein by reference in their entireties.

[0020] In the preferred embodiment as shown, the cabinet 100 is a segmented side wall pharmaceutical cabinet 100 having a housing including a top surface 101 and a base 102. The cabinet is provided with casters 104 and may be used as a pharmaceutical dispensing cart. The cabinet housing further includes a base side wall segment 103, middle side wall segments 105 and a top segment 106. It is provided with a plurality of drawers 109 for containing various items and a plurality of pharmaceutical cassettes 107, each containing a plurality of bins 108. Each of the cassettes 107 comprises two rows of bins 108 disposed in a side-by-side relation, and is slidably removable from cabinet 100. Each of the cassettes 107 is further provided with a horizontally extending bin locking barrier 116 extending frontally along a lower portion of an upper row of bins and an upper portion of a lower row of bins. The bin locking barriers 116 have an elongated cross section and are rotatable between a horizontal releasing position allowing for removal of individual ones of the bins 108 and a vertical locking position in which removal of the bins 108 is restrained.

[0021] A vertically extending cabinet locking barrier 110 is hingedly attached to one side of cabinet 100 by a hinge 111 and is rotatable between a locked position as shown in FIG. 1 and an unlocked position as shown in FIG. 2. In the embodiment shown, the locking barrier 110 is formed as a lock bar, but those skilled in the art will appreciate that in other embodiments the locking barrier 110 could be formed as a door, shield, or other barrier having a locking mechanism. When in the locked position, as shown in FIG. 1, cabinet locking barrier 110 cooperates with the horizontally extending bin locking barriers 116 of the individual cassettes 107, to lock each of the individual bins 108 in the cart. The details of the structure and operation of the cassettes 107, bins 108, and horizontally extending bin locking barriers 116 are described in detail in the above referenced patents.

[0022] The locking barrier 110 includes a rotatable handle 112 for opening for the locking barrier 110. When the locking barrier is locked, the handle 112 is only rotatable after unlocking the locking barrier 110 using the key core 114 or the key button pad 118.

[0023] FIGS. 3-8 illustrate the locking mechanism 120 (FIG. 5) of the preferred embodiment. The locking mechanism 120 is disposed within the locking barrier housing defined by front panel 160, a spaced rear panel 162, a bottom cap 164, and a top bracket 166 and a detent housing 200. The locking mechanism 120 includes locking members defined by an upper locking pin 122 and a lower locking pin 124. Locking pins 122 and 124 are oriented so as to move in substantially parallel but opposite directions. Locking pins 122 and 124, when in an extended position as shown in FIG. 5, engage cavities (not shown) in the cabinet 100 and thereby secure the locking barrier 110 in a closed position. When locking pins 122 and 124 are in the retracted position (as shown in FIG. 6), the locking barrier 110 is rotatable along hinge 111 to any of its open positions.

[0024] The locking pins 122 and 124 are connected to an actuator disk 126 at lateral positions thereof. The actuator disk 126 is rotatable about an axle assembly 128 (FIG. 5) disposed normal to the front panel 160. The opposite end of the axle assembly 128 is connected to a manual actuator defined by a rotatable handle 112 mounted on the front panel 160. Thus, the actuator disk 126 is rotatable by manual turning of actuator handle 112.

[0025] As shown in FIG. 5, the actuator disk 126 is biased by a spring element 130 to a locked position. The opposite end of the spring element 130 is connected to an extension 167 of top bracket 166. In the locked position as shown in FIG. 5, the locking pins 122 and 124 are held in an extended position by virtue of their connection at lateral positions of the actuator disk 126 which are now raised and lowered, respectively. In the unlocked position as shown in FIG. 6, the locking pins 122 and 124 are held in a retracted position because the lateral positions of the actuator disk 126 are lower and higher, respectively, as compared to their positions when the actuator disk 126 is in the locked position.

[0026] The locking mechanism also includes a lever 140 and a cam 152. The lever 140 is mounted at a pivot axle 142, which is in turn mounted to a mounting bracket 150 (see FIG. 3; the mounting bracket 150 is shown in phantom the FIGS. 5 and 6). The lever 140 is biased by a spring element 144 to a locked position as shown in FIG. 5. In the locked position, a disk engaging portion defined by a flange 143 (FIG. 3) extending perpendicular to the end of the lever 140 fits into slot 127 of actuator disk 126. When engaging and residing in the slot 127, the flange 143 renders the actuator disk 126 incapable of movement, and thus maintains the locking mechanism 120 in its locked position.

[0027] The flange 143 can be removed from the slot 127 by rotation of cam 152 and thus the lever 140, as shown in FIG. 6. The cam 152, in turn, is moveable only by rotation of lock core assembly 114. Alternately, the flange may be removed by a rod 172 defining a release member. The rod 172 is moveable downward by knob 119 (FIG. 1) only after the correct sequence of buttons 117 (FIG. 1) have been pressed by the user. Thus, once the locking mechanism 120 is in a locked position, only turning of the rotation of the lock core assembly 114 (FIG. 1), such as by a key, or pressing of the buttons 117 will permit movement of the locking mechanism to an unlocked position, and thus subsequent movement of the locking barrier 110 to one of its opened positions.

[0028] The actuating member 126 may be rotated by handle 112 (FIG. 1) after the flange 143 has been removed from the slot 127. The gate member 145 is attached to the actuating member 126 by a pivot axle 147. The gate member 145 is biased to a slot covering position by spring 146, so that once the flange 143 is removed from slot 127, the gate member 145 covers slot 127 and prevents flange 143 from re-entering the slot 127. Therefore, the locking barrier 110 can be opened with one hand because the handle 112 can be turned without simultaneously holding a key in the lock core 114 or the knob 119 in the open position.

[0029] The locking mechanism 120 is designed to lock automatically, after rotation and removal of the key, and upon movement of the locking barrier 110 from an open position to its closed position, as will be described in detail below.

[0030] As shown in FIGS. 2-6, a detent housing 200 is mounted atop the locking barrier 110. As shown in FIGS. 7 and 8, the detent housing 200 houses a contact portion of the locking mechanism 120 defined by a detent element 202. A flange 204 of the detent element engages channel 206 and thus the detent element is free to pivot between an unlocked position as shown in FIG. 7 and a locked position as shown in FIG. 8. A spring element 208 resting in channel 209 biases the detent element 202 to the locked position. In the unlocked position, an end portion of the detent element 202 resides in a machined shoulder 123 (see FIG. 4) at the top of the locking pin 122. When the detent element 202 resides in the shoulder 123 and thus prevents the locking pin 122 from upward movement, the entire locking mechanism 120 is held in an unlocked position as shown in FIG. 6.

[0031] The detent housing 200 includes a cavity 210 that communicates with the detent element 202. The cavity 210 is positioned in the housing such that when the locking barrier 110 is in its closed position, an actuation projection 230 (shown in FIGS. 2 and 4, and in phantom in FIG. 7) attached to the cabinet 100 extends into the cavity 210. The actuation projection 230 is dimensioned such that it contacts the detent element 202 and moves it away from the locking pin 122. Once the detent element 202 clears the shoulder 123 of the locking pin 122, the locking pin 122 is free to extend through a locking member aperture 212 of the detent housing 200 and into its locked position. Because the actuator disk 126 is biased by the spring element 130, the movement of the actuator disk 126 and thus the locking pins 122, 124 is automatic upon clearance of the detent element 202 from the shoulder 123. Furthermore, as long as the lock core 114 or knob 119 are not held in the open position, spring element 144 causes the lever flange 143 to urge against the periphery of actuator member 126. The level 140 contacts portions 148 and 149 of gate member 145, and pushes gate member 145 clear of the slot 127. The flange 143 then enters slot 127, thereby locking the actuator disk 126. Thus, closure of the locking barrier 110 results in automatic locking of the locking mechanism 120.

[0032] The elements shown in the preferred embodiment are designed to be fully reversible to facilitate placement of the locking barrier 110 on either side of the cabinet 100. For example, as shown in FIGS. 7 and 8, in a reverse orientation, the detent element flange 204 could be mounted in channel 305, the spring element 208 mounted in channel 309, with the locking pin 122 extending through locking member aperture 312. The actuator disk 126 could also be flipped over in a reverse orientation, with the spring element 130 attached to a leg 367 of the bracket 166. Likewise, the lever 140, the cam 152, and the spring element 144 are readily repositioned to support this reverse orientation.

[0033] The locking barrier 110 may also include an alarm 280 (FIG. 3) for signaling to the user the locking barrier 110 has been in an unlocked position for a specified period of time. The details of the alarm 280 are disclosed in co-pending U.S. application Ser. No. ______ (Attorney Docket No. 4634/133) entitled “Alarm for Locking Mechanism, And Cabinet Using Same,” filed Dec. 7, 2000, the entire disclosure of which is incorporated herein by reference.

[0034] It should be readily understood by those persons skilled in the art that the present invention is susceptible of a broad utility and application. Many embodiments and adaptations of the present invention other than those herein described, as well as many variations, modifications and equivalent arrangements will be apparent from or reasonably suggested by the present invention and the foregoing description thereof, without departing from the substance or scope of the present invention.

[0035] For example, although the locking barrier has been shown as a lock bar in the preferred embodiment, the locking mechanism of the invention could be used in a door or shield. Accordingly, while the present invention has been described herein in detail in relation to a specific embodiment, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for purposes of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended or to be construed to limit the present invention or otherwise to exclude any such other embodiments, adaptations, variations, modifications and equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.