0 United States Patent [151 3,635,173 Ruben [4 1 Jan. 18 1972 [54] SELF-LEVELING DISPENSER 2,626,727 1/1953 Gibbs ..312/71 2,775,352 12/1956 Waite ....312/71 [72] Invent z" Hdsmf 2,806,607 9/1957 Korngold.... .108/136 2,932,403 4/1960 Vershbow 211/49 R [73] Assignee: AMF Incorporated 3,381,634 5/1968 Rothschild. ..108/136 [22] Filed M 30 1970 3,428,185 2/1969 Vorndran ..312/71 [21] App]. No.: 23,713 Primary Examiner-Francis K. Zugel Attorney-George W. Price [30] Foreign Application Priority Data [57] ABSTRACT June 18, 1969 Great Britain ..30,860/69 A selflevefingsmring and dispensing device which includes a horizontally oriented platform carriage which is directly con- ..IOSIIfijJfi/Z); meted, via a P1 y of tension springs to the upper and of I an upright housing for g a workpiece 103 d at a [58] Fieldof Search ..108/136, 312/71, 211/49 predetermined leveL The carriayge is guided by the housing in a vertical path of travel as the springs expand and contract in [56] References and response to the workpiece being respectively loaded on the UNlTED STATES T N platform and removed therefrom.
2,560,928 7/1951 Bockius ..108/l36 1 Claims, 4 Drawing Figures PATENTEUJANIMSYZ 3535173 SHEET 1 OF 2 /Z4 INVENTOR.
NAPOLEON H. RUBEN PATENTEB Jam 8 1912 SHEET 2 UF 2 INVENTOR.
........ I as NAPOLEON H. RUBEN SELF-LEVELING DISPENSER BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to materials handling apparatus and more particularly to self-leveling and storing and dispensing devices of the type wherein a platform, on which a plurality of articles of like height and weight may be stacked, is connected to an upright housing via spring means and guided by the housing in a vertical path of travel.
In apparatus of the aforesaid type the springs are chosen to axially expand or contract a distance which is approximately equal to the height of one of the articles being placed on or removed from the platform. Assuming a plurality of like articles of any given stacked height on the platfonn, the platform is adapted to move upwardly a distance approximately equal to the height of an article when it is removed from the platform, and move downwardly the same distance when a like article is added. The topmost article in a stack of like articles is thus automatically located at a predetermined constant level irrespective of the height of the stack.
One of the difficulties associated with such apparatus is that the platform tilts when the articles stacked thereon are not properly centered on the platform. For example, if the article placed on the platform is a half-filled, rectangularly shaped basket of drinking glasses, and the glasses are disposed in the bottom of the basket so as to eccentrically load the platform, a tilting moment is exerted on the platform which may cause the platform to jam.
In the prior art, the problem has been alleviated through the use of apparatus comprising a housing from which the platform is suspended at its four corners by four spring-loaded chains whose respective incremental movements are synchronized by four sprockets keyed to a common shaft. The arrangement keeps the platform level, but the apparatus takes up too much space as compared to its useful area for storing and dispensing articles, is prone to failure due to the development of friction forces, is noisy during operation and expensive to manufacture. Consequently, a need exists for a device having an improved ratio of net useful area to its bulk size; a device which is simply and inexpensively constructed and provided with means for stabilizing its platform to allow for uneven loading.
Another problem encountered by the users of prior art devices is the need to bring in a manufacturers representative, or other highly skilled technician, to adjust the spring tension or compression to accommodate a change in the type of stackable article for which the device is used. A change in either the weight or height of the workpiece stored or dispensed calls for an adjustment of the response of the platform to loading conditions. For first use, consumers have been accustomed to sending the manufacturer a sample of the type of workpiece they will be stacking, so that the manufacturer can match the spring or springs used to the workpiece handled. Since the versatility of the devices are thus severely curtailed, is should be appreciated that a need exists for a selfleveling device provided with means for allowing relatively unskilled personnel to easily adjust the response of the platform to different workpiece loads.
This invention overcomes the aforesaid problems of the prior art and at the same time provides a simply constructed, inexpensively fabricated device of the type described. The invention hereinafter described in detail generally comprises: an upright housing, horizontally oriented platform carriage adapted to be suspended from the housing and carry a workpiece load, a plurality of tension springs adapted to be connected to the housing and carriage, at least one of the springs having its upper end directly connected to the upper end of the housing and its lower end directly connected to the carriage to suspend the platform from the upper end of the housing and at a given reference level such that the level of the platform decreases an incremental distance from the reference level in response to the load being placed on the platform and returns to the reference level when the load is removed, the tension springs which are connected to both the housing and carriage being chosen from the aforesaid plurality thereof such that the incremental distance is approximately equal to the height of the aforesaid load, and means cooperatively associated with the carriage and housing for guiding the platform in a vertical path of travel, the guiding means constructed and arranged to compensate for loading moments which tend to tilt the platform forwardly or laterally of the housing.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a self-leveling storing and dispensing device;
FIG. 2 is a sectional view of FIG. 11, taken substantially along the line 2-2 thereof;
FIG. 3 is a sectional view of FIG. 2, taken substantially along the line 33 thereof; and
FIG. 4 is a sectional view of FIG. 3, taken substantially along the line 4-4 thereof.
DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in the drawings, wherein like reference numerals designate like or corresponding parts throughout the several views, the preferred self-leveling storing and dispensing device 10 is basically a horizontally extending platform carriage, generally designated 12, which is movably connected to an upright housing generally designated 14. The carriage is preferably directly connected to the housing via at least one of a plurality of tension springs 16 provided with the apparatus.
The housing 14 is a vertically oriented enclosure of sheet metal construction and has a generally rectangularly shaped horizontal cross section. In the preferred embodiment it has opposing front and rear walls, respectively designated 20 and 30 in the drawings, a pair of opposing sidewalls 40, and opposing top and bottom walls, the latter being respectively designated 50 and 60 in the drawings.
The front wall 20 is made of two elongated U-shaped panel members 22 arranged side-by-side and lengthwise welded together so that the front wall has an E-shaped horizontal cross section. As will hereinafter be more fully explained, together, the abutted legs 24 of the panel members 22 act as a guide for the platform carriage. The front wall is mounted on the bottom wall 60, a panel member of elongated U-shaped cross section having upwardly extending legs 64 and 68 and provided with a pair of elongated L-shaped members 62. One leg 62A of each of the members 62 is welded to the bottom wall and the other 628 extends upwardly therefrom to act as a tab to which the front wall is spot-welded. When assembled, the front walls inner surface is facewise abutted to the aforesaid upwardly extending legs 62B of members 62 for welding thereto. In addition, the lower edge of the front wall 20 is edgewise abutted to the forward edge of the bottom wall, the front leg 64 of the bottom wall being formed to extend upwardly and laterally of the housing and act as a base upon which the front wall is mounted. The rear leg 68 of the bottom wall extends upwardly and laterally of the housing and acts as a base upon which the rear wall is mounted.
The rear wall 30 is an elongated, flat, rectangularly shaped plate of lesser vertically extending length than the front wall. After edgewise mounting it on the rear leg 68 of the bottom wall, its inner surface is preferably riveted to the rear legs 42 of the sidewalls 40, each of which is preferably an elongated U-shaped panel member having a vertically extending guide member 43 welded to its inner surface. The forward legs 44 of the sidewalls are connected to both the bottom and top walls; the lower end of the forward leg 44 of each sidewalls being preferably spot-welded to the inner surface of the forward leg 64 of the bottom wall 60, and the upper end being similarly connected to the top wall 50. In the preferred embodiment, each of the guide members 43 is a length of tube of rectangu larly shaped cross section that is spot-welded in place to its associated side panel.
The top wall 50, like the bottom wall, is generally rectangularly shaped and has L-shaped members 52 welded thereto. In this instance, the downwardly extending leg 53 of each of the L-shaped member 52 is abutted to the front wall panel members for spot-welding thereto. In addition, the top wall has a laterally extending forward leg 54 which bends the forward edge of the top wall downwardly for edgewise abutment with the top edge of the front wall. Opposing downwardly extending side portions 56 of the top wall have their inner surfaces welded to the outer surfaces of their associated side panels as shown in FIG. 3.
As hereinbefore indicated, the rear wall is of lesser vertically extending length than the front wall. Its length is foreshortened to provide an opening 35 into the housing for access to the springs, an opening which is preferably approximately I65 millimeters high. A rectangularly shaped flap door 36 hinged, or otherwise pivotally connected to the rear leg 55 of the top wall, is provided to normally close the access opening 35. The flap door is preferably secured closed by a magnetic snap lock (not shown). In addition, to this opening, the front and sidewalls are connected to the top and bottom walls to form a pair of slit-shaped openings 37 at the front of the housing as shown in FIG. 1. These openings are situated between the front and sidewalls, and extend vertically between the top and bottom panels.
A spring hanger bar 58 of elongated U-shaped cross section, is spot-welded in place to the inner surface of the top wall so as to extend laterally across the upper end of the housing. The bar 58 is preferably provided with a plurality of equidistantly spaced openings formed in each of its legs to accommodate the direct suspension of two rows of springs from the upper end of housing. Each of the seven springs in the front row 16A preferably has a spring characteristic of grams per millimeter of axial extension, whereas each of the four springs in the rear row 163 preferably has a spring characteristic of grams per millimeter. The preferred inventory of 11 springs affords the user a broad selection of spring combinations to change the response of the platform to loading. In effect, the spring characteristic of the carriage, and thus the platform 12A may be changed in S-gram-per-millimeter increments up to a maximum of I85 grams per millimeter, with a preferred minimum of 35 grams per millimeter, by changing the number of springs which are connected to the platform carriage 12.
As shown in drawings, all of the springs have their upper ends connected to the upper end of the housing, but less than all have their lower ends connected to the carriage 12. The latter group of springs are representative of any number of the total which may be chosen to suspend the platform from the housing so that it is lowered a predetermined distance in response to a particular workpiece load being placed thereon. As indicated in the introductory portion of this specification, the predetermined distance is an incremental portion of the total distance the platform is able to travel and is chosen to correspond to the height of the particular workpiece. When the workpiece is placed on the platform, the platform is lowered the aforesaid incremental distance in response to the weight of the workpiece, the springs connected to the carriage axially expanding the same distance. Subsequently loaded workpieces of like weight, which are usually stacked on the top of the first workpiece, further lower the platform a like incremental distance.
As best shown in FIG. 2, in the preferred embodiment the platform carriage 12 includes a U-shaped front plate 80 which extends between opposing sideplates 81, an elongated U- shaped tie bar 82, which also extends between the side plates, and a plurality of guide rollers 83. The respective inner surfaces of the sideplates 81 are oriented parallel to one another and welded to the outer surfaces of the legs of the front plate 80, so that the sideplates extend both forwardly and rearwardly of the laterally extending base portion of the front plate. The tie bar 82 is endwise welded to the inner surfaces of the opposing sideplates so that it is oriented parallel to the aforesaid base portion of the front plate.
As best shown in FIGS. 3 and 4, the carriage is suspended within the housing by connecting the lower end of one or more of the springs to the tie bar 82. In the preferred embodiment the tie bar 82 is of the same construction as the hanger bar 58, each of its legs is provided with a plurality of equidistantly spaced openings which are formed therein to accommodate directly connecting the lower ends of the springs thereto and thus to the carriage.
As best shown in FIG. 3, in the preferred embodiment the carriage is provided with a pair of nylon rollers 83A pivotally connected to each of its sideplates 81 and two pairs respectively numbered 838 and 83C, connected to its front plate 80. As best shown in FIG. 4, each of the sideplate roller pairs 83A includes an upper roller spaced vertically above and rearwardly of an associated lower roller, whereas each of the front plate roller pairs 838 or 83C, includes an upper roller spaced vertically above and laterally of an associated lower roller. As shown in FIG. 2, each of the upper side plate rollers 83A is in rolling contact with the rearwardly facing surface of one of the sidewall guide members 43 and its associated roller is in rolling contact with the forwardly facing surface of the same guide member. As a consequence, the platform is prevented from tilting forwardly of the housing when a load is placed thereon. The platform is similarly prevented from tilting laterally of the housing by the front plate rollers. The upper roller of a given front plate roller pair 83B or 830, is in rolling contact with one side of the front panel guide 24 and the other roller of the same pair is in contact with the opposite side of the same guide. Since there are upper and lower front plate rollers on each side of the guide 24, the platform carriage is constrained to move vertically despite its being subjected to moments of force tending to tilt the platform in either direction laterally of the housing.
As shown in FIG. 1, in the preferred embodiment each of the sideplates 81 of the carriage protrude through one of the slit-shaped openings 37 in the front of the housing. Although these plates may each be constructed from a single piece of metal, in the preferred embodiment they are equidistantly foreshortened to protrude from the housing a sufficient distance to bolt a reinforcing member 81A and triangularly shaped terminating members 818 to the end of each of them. The latter member 818 acts as the immediate carrier of the platform in the preferred embodiment, whereas the sidewalls of the carriage are the ultimate platform carrier.
In practice, the flap door at the rear of the housing is opened to gain access to the springs whenever it is desirable to change the spring characteristic of the carriage. Any number of springs, or all of them, may be utilized for a given workpiece load, those not in use simply being left inactively hooked in place to the hanger bar. Without the use of tools, properly instructed unskilled labor is thus enabled to readily adjust the spring characteristic of the platform.
As shown in FIG. 1, in the preferred embodiment the housing may be made mobile by bolting each of its sides to an elongated U-shaped base member having front and rear swivel wheels 92 depending therefrom. To promote stability of the base members 90, their front ends are preferably interconnected to one another via a third elongated U-shaped base member 94, the length of which is approximately equal to the width of the housing 10.
What is claimed is:
1. A self-leveling storing and dispensing device comprising an upright boxlike housing having opposed spaced parallel front and rear walls and pair of sidewalls and a top wall for closing the upper end of said housing, a vertically movable platform disposed in front of said housing, said platform being supported by a vertically movable carriage disposed in said housing, said carriage comprising a pair of opposed spaced parallel sideplates which are interconnected by a front plate, said sideplates being disposed in opposed spaced relationship to said sidewalls and said front plate to said front wall, a vertical guide rail extending centrally along each said front and sidewalls, and rollers on each of said front and sideplates encoil springs having hook ends, said springs being suspended off the apertured U-shaped member on said top wall, and an access door in said rear wall for affording access to the interior of said housing for manually selectively connecting the other ends of said springs to the other U-shaped member, and a pair of vertically extending slots formed in said front wall along opposite edges thereof, portions of said sideplates extending through said slots, and said platfonn being supported on said sideplate extending portions in front of said front wall.