Referring to the drawings, and more particularly to FIGS. Each of the slidable trays 2 is supported by ledges 3 located adjacent to the opposite sides of the tray, each of the ledges having an upstanding flange 4 attached to one of the vertical walls 5 of the cabinet. Extending across the lower rear portion of the tray 2 and between vertical flanges 6 provided on the tray is a rotative shaft 7 carrying a roller 8 at each of its ends, said rollers riding upon the ledges 3 which form supporting rails to thereby permit the easy back and forth sliding movement of the tray 2 to bring it to either the advanced or projected position of FIG.
The shaft 7 also carries at each of its ends, a pulley 9 around which a flexible cable 10, preferably of stranded metallic material, extends. Each of these cables 10 is anchored at its forward end to a bracket 11, said brackets being attached to to respective side walls of the cabinet. From the pulleys 9, each of the cables 10 extends upwardly to pass around an upper pulley 12, said pulleys 12 being carried on a cross shaft 13, rotatable in the flanges 6 at the back of the tray.
Rollers 14 are also carried by the upper shaft 13, said rollers engaging under guide plates 15 mounted on the walls of the cabinet. This arrangement provides for easy sliding movement of the tray. From the pulleys 12, the cables 10 extend rearwardly to pass around pulleys 16 carried on stud shafts 17 mounted in angle brackets 18 secured to the rear wall of the cabinet. The rear end of each of the cables 10 is attached by screw 19 to a stud 20 mounted in the bracket The brackets 18 are each provided with a lug 21 through which an adjusting screw 22 threadably passes, said screw being provided at one end with a head 23 for engagement against the portion of the cable 10 that is located between the anchorage point 19 of the cable and the guide roller The above-described arrangement is such that by the turning of the screws 22 the two cables 10 can be constantly maintained under the required tension in order to secure the most efficient balanced operation of the tray.
By the manual turning of the adjusting screws to the required extent, the desired tension can thus be applied to the cables or either of them. The adjusting screws 22 each have a knob 24 to facilitate their manual adjustment. The portion of the cabinet in which each of the trays is housed is normally closed by a door 25 supported by square supports The closed position of the door, when the tray is in its retracted position, is shown in FIG.
In any event, it certainly would have been known to a skilled worker in the art of office furniture. Its application in closely related fields is illustrated by United States Patent No. Copeland, and British Patent No. Ohlson and Mr. See LTV, Inc.
Kollsman Instrument Corp. Supermarket Equipment Corp. See Lorenz v. Woolworth Co. It would have required no more than the exercise of mechanical talent on the part of those having ordinary skill in the art of office furniture to have employed the age-old pulley system, previously utilized in closely related fields by Copeland, Ohlson and Lundberg, to limit the number of drawers that could be maintained in opened positions as Bolesky and Saaf had taught, especially in view of the Hartbeck Patent which disclosed that a cord and pulley system could be utilized to effectuate the movement of vertically disposed drawers.
The secondary considerations of long-felt need and commercial success, Graham v. It is urged that conventional file cabinets have always lacked stability, that a number of patents for mechanical interlock mechanisms designed to remedy this problem have issued, and that many companies are now utilizing a cord interlock device to eliminate tipping.
This evidence here, however, does not necessarily point to invention. There is no indication of actual use of any interlocking device in conventional filing cabinets prior to that by Levenberg. This non-use may be attributed to the lack of a satisfactory prior art device, but it could also be due to a belief by the industry that the problem was not of sufficient magnitude to justify their use. The present use of cord interlocks seems readily explainable by the fact that in the mid's a new type of file cabinet became popular which has a narrower base and therefore a greatly increased potential for tipping.
In view of the previously discussed prior art, patentability cannot be predicated on the speculation about need and commercial success that is required here. See Anderson's-Black Rock, Inc. Pavement Salvage Co. In sum, we find all the claims of the Levenberg Patent lacking in patentable subject matter and accordingly affirm so much of the district court's judgment as declares claims invalid; as to claims 1 and 2 we reverse and remand with instructions to modify the judgment to include a declaration that claims 1 and 2 are also invalid.
Tilt-proof cabinet construction comprising: a housing, a pair of drawers slidably arranged for movement within said housing and outwardly thereof, and means engaging a portion of each drawer and a fixed surface of said housing for permitting only one of said plurality of drawers to be selectively withdrawn to maximum extension outwardly of said housing, said means including a flexible cord of predetermined length, eyelet means on an inner surface of said housing, said cord slidably passing through said eyelets, said cord having first and second ends, at least one of said ends being maintained in fixed relation relative to said housing during movement of either drawer to full extension.
Lear Siegler, Inc. In addition to the horizontally disposed drawers 82, a drawer which is in a vertical relationship to one of the horizontal drawers 82 may also be mounted in the cabinet. Disposed beneath the drawers 82 and extending the width thereof is a channel 88 similar to channel 24 described above with reference to the first embodiment. The channel has a U-shaped configuration with a central web Perpendicular to the channel 88 and adjacent the sides of the drawers 82 are guide tracks Each guide track 90 has a shallow U-shaped configuration from which extends a rotatably mounted actuator or forked member 92 similar to that described above.
The actuator 92 includes a slot 94 which receives a pin 96 extending from each side of a drawer. Rotatably secured with the actuator by means of a pivot pin 98 is a cam member The cam and actuator 92 are disposed on opposite sides of the guide track Slidable within the guide track 90 and vertically displaceable therein is at least one follower The follower is in the form of a generally rectangular block having a projection at the bottom portion thereof.
As can be seen, rotation of the cam causes the follower to be displaced within the guide track The channel 88 disposed beneath the drawers 82 is similar to that described above in that it includes a series of blocks and wedges which are slidable therein. The blocks have a polygonal configuration with one end surface angled relative to central web 84 of the channel The other end of the block is generally perpendicular with respect to web 89 of the channel The wedges slidable in the channel are identical to those described above and include an angled end which is slidable over angled surface of the blocks and an end which is perpendicular to the central web 89 of the channel.
In order to fix the length over which the blocks and wedges are slidable in the channel, an adjustable wedge is mounted at one end thereof. The adjustable wedge is adjustable in the channel so as to abut the adjacent wedge so as to limit horizontal displacement of the blocks and wedges when a drawer is opened.
The channel 88 abuts the wall 84 of the cabinet at the end opposite that at which the adjustable wedge is mounted to likewise limit horizontal displacement of the blocks and wedges. As can be seen, the blocks and wedges are alternatively arranged with one wedge disposed beneath a follower of each drawer Accordingly, for a two drawer system, two slidable wedges and one slidable block are mounted within the channel For a three drawer system, there are two blocks and three wedges , one wedge for each drawer.
With reference to FIG. In this embodiment a second cam and follower arrangement is disposed in the guide track 90 with the follower vertically disposed over the follower of the lower drawer. The actuator and cam arrangement is the same as that described above. The upper follower includes a projection which bears against the top surface of the lower follower Accordingly, as the top drawer 83 is opened the cam forces the upper follower downwardly so that the projection in turn urges the follower adjacent the lower drawer 82 downwardly towards the channel 88 to thereby displace the wedge therein.
In operation, as one of the drawers 82 of the cabinet is opened, the pin 96 which extends from the side of the drawer 82 is received in the slot 94 on the actuator 92 or forked member to thereby rotate the actuator Rotation of the actuator 92 rotates the attached cam which travels over the top surface of the adjacent follower The configuration of the cam therein forces the follower downwardly so that the projection on the bottom thereof urges against the top of the wedge which is spaced from the central web 89 of the channel.
In this way, the wedge is displaceable downwardly in the channel. Downward displacement of the wedge in the channel 88 causes relative sliding between the blocks and wedges over the angled surfaces , thereof so as to spread the blocks and wedges toward the ends of the channel.
The displacement of the wedge in the channel causes the remaining wedges to ride upwardly in the channel so as to bear tightly against the projections on the followers In this way, a second drawer in the cabinet cannot be opened since there is no room for further sliding of the wedges and blocks Any attempt to open a second drawer 82 is blocked since the downward movement of the follower would be resisted by the wedges which are held firmly in place.
When the system is used in a cabinet including vertically-arranged drawers as in FIG. The remaining operation of the drawer is as described above with the follower displacing the wedge in the channel so as to force the wedges and blocks outwardly and take up the slack therebetween.
The above-described interlock mechanisms for filing cabinets or the like provides a relatively simple means for preventing the opening of more than one drawer in the cabinet. The channels including the blocks and wedges may be assembled in components so that a number of such assemblies including channels of a specified length may be mounted in a cabinet depending upon the number of drawers in the cabinet.
It is only necessary to provide one wedge for each drawer along with one actuator and cam mechanism. Also, assembly of the cabinet including such an interlock mechanism is relatively easy in that the channels, either vertically or horizontally arranged, are mounted to the cabinet walls. This is in distinction to cable interlock systems wherein the cable must be secured to cams or other stop members onto the cabinet as well as to drawers. Additionally, the use of rigid members as opposed to cables or the like may provide a more durable interlock system in that the probability of the parts failing is minimal.
The foregoing and description of drawings are merely illustrative of the invention and are not intended to limit the invention to the above-described embodiments. Variations and changes which may be obvious to one skilled in the art may be made without departing from the scope and spirit of the invention as defined in the appended claims. The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 1.
In a cabinet including a housing, at least two drawers, means slidably mounting said drawers to the housing and an interlock mechanism for preventing the simultaneous opening of two drawers, the improvement in said interlock mechanism comprising: an elongate channel mounted to said housing adjacent said at least two drawers, said channel having a fixed length and depth and including a bottom wall;.
The cabinet of claim 1 wherein said actuator means includes an engagement member secured to said cam means and rotatable therewith and a pin extending from said drawer, wherein said pin is received by said engagement member upon opening and closing of said drawer to thereby rotate said cam means. The cabinet of claim 2 wherein said engagement member is a U-shaped member pivotably secured to said channel. The cabinet of claim 1 wherein said channel includes stop members secured at ends thereof so as to define the fixed length of the channel.
The cabinet of claim 3 wherein said drawers are arranged in a vertically-stacked relationship and said elongate channel is vertical. The cabinet of claim 5 wherein said actuator means includes a U-shaped member secured with said cam means and rotatable therewith and a pin extending from a side wall of the drawer which is received by the U-shaped member upon opening and closing of the drawer.
The cabinet of claim 6 wherein said cam means includes a cam surface which travels over a surface of said wedge members upon opening of one drawer to thereby displace said wedge member relatively into said channel.
The cabinet of claim 1 wherein said drawers are arranged in a side-by-side horizontal relationship and said elongate channel is disposed beneath said drawers.
The cabinet of claim 8 wherein said actuator means includes a U-shaped member which is secured to said frame and a pin extending from the side wall of the drawer which is received by the U-shaped member upon opening and closing of the drawer. The cabinet of claim 9 wherein said cam means includes a cam member secured with said U-shaped member and rotatable therewith and a follower which is vertically displaced by said cam member upon opening and closing of said drawer, said follower being vertically displaceable in a guide secured to said housing.
The cabinet of claim 10 wherein said follower includes a projection which bears against said wedge member so as to force said wedge member relatively into said channel upon opening of the drawer.
The cabinet of claim 8 further including a drawer arranged in a vertical relationship relative to one of said at least two drawers arranged in a side-by-side horizontal relationship. The cabinet of claim 12 including cam means adjacent each of said vertically-arranged drawers. The cabinet of claim 13 wherein said cam means includes a cam member secured with said actuator means and rotatable therewith and a follower vertically displaced in a guide on said housing by said cam member so that the followers of both of the vertically-arranged drawers are disposed in a vertically-stacked relationship, whereupon opening of the upper drawer of said vertically arranged drawers causes said adjacent cam means to displace said vertically stacked followers and thereby force said wedge relatively into said channel.
USA en.
0コメント