US 3376085 A
Description (OCR text may contain errors)
April 2, 1968 P. F. MOPHERSQN 3,376,085
ADJUSTABLE DISH DISPENSER Filed Oct. 21, 1965 FIG. I 8
INVENTOR. PATRICK FRED M PHERSON v United States Patent ABSTRACT OF THE DISCLOSURE A self-levelling, storing and dispensing apparatus comprising, a housing, a helical compression spring having a predetermined constant supported in said housing, a carrier connected to the upper end of said compression spring for supporting material stored in said housing, and a rod, vertically adjustable through a series of integral lateral projections connecting said carrier and a plate over said spring, said projections bearing serially and selectively against said plate, whereby the constant of said spring may be altered by limiting the distance said rod passes through said plate, the bottom of said rod being connected to said housing to maintain the level of said carrier constant as the constant of said spring is varied.
Summary A self-levelling, storing and dispensing apparatus which includes a housing, a helical compression spring supported in said housing and having a predetermined constant, a carrier connected to the upper end of said compression spring for supporting material stored in said housing, and means comprising a plurality of fixed stops for selectively limiting the upward expansion of said spring whereby said predetermined constant may be varied.
This invention relates to self-levelling, storing and dispensing apparatus such as that shown in US. Patent 3,004,813 granted Oct. 17, 1961 to H. L. Shivek.
Apparata of this type find Wide application in many fields, such as restaurants, cafeterias and industry, where they may be employed for articles such as dishes, work in progress, etc. which they store and automatically dispense at convenient height.
Briefly, such a device comprises a housing in which a vertically moveable work carrier is supported by a helical spring. Whenever the user stacks items on the carrier, the latter descends against the spring an amount theoretically equal to the weight of the items placed thereon so that the topmost item is always at the same level.
In practice, however, certain problems arise because of the weight characteristics of different items, or varieties of similar items. Heretofore, in order to cause these devices to function correctly for a particular item, it was necessary to provide a spring having a constant that was a direct function of the item to be stored. Because of the great diversity in existing items, this has required that hundreds of different springs be kept in stock and that final assembly of a device could not be completed until after it was sold and not until the exact weight of the item to be stored was known. Furthermore, once such a device was assembled, it could not be varied to accommodate different items or to change its capacity unless it was dismantled and its spring replaced with another.
It is an object of the present invention to provide a simple mechanism for varying the load carrying characteristics of a self-levelling dispenser.
It is another object to provide a mechanism for varying the capacity of a self-levelling storing and dispensing device.
It is a particular object of the present invention to provide a mechanism for varying the characteristics of the helical spring employed in a self-levelling storing and dispensing device.
These and other objects, as well as numerous advantages, will appear from the following description in which reference is made to the accompanying drawings in which:
FIG. 1 is a vertical view partly in section of a dispenser embodying the present invention;
FIG. 2 is a plan view showing the spring top plate;
FIG. 3 is a perspective view of a spring anchor according to a first embodiment of the invention; and
FIG. 4 is a perspective view of a spring anchor according to a second embodiment of the invention.
In the drawings, there is shown a self-levelling dispenser particularly adapted for plates or dishes, comprising a housing 1 generally of tubular form whose dimensions correspond to those of the items to be stored. The housing includes a bottom 2 at the center of which is rotatably attached a chain 11 which extends axially into the interior of the housing 1.
The upper extremity of the housing 1 is open and is furnished with bars 8 to guide the stack of items, in this example, dishes and plates -13 emerging from the housing 1. A moveable carrier 9 is located inside the housing 1 and is supported on a helical spring 12 which rests on a bottom disc 5. Carrier 9 has a depending skirt 10, the purpose of which is to act as a guide for the carrier and to avoid jamming in the course of its vertical movement. The carrier 9 is connected to a cable 11 or other flexible mechanism, by an adjustable spring anchor 3 passing through a spring top plate at an opening 6, so as to limit the carriers upward travel. The length of cable is chosen so that the carrier 9 at its maximum upward distance is substantially level with the top of housing 1. In this position, it is preferable that the spring 12 be under a certain degree of pre-compression which is obtained or regulated by varying the vertical relation between the anchor 3 and the plate 4.
In accordance with the present invention, there is provided a mechanism for adjusting and regulating the force of the spring so as to enable it to accommodate varying weights. This device is intended to operate in such a manner as to render inactive one or several turns or fractions of turns of the helical spring 12, thus causing the constant of the spring to be modified. With such a device, it is possible to use the same spring in a single apparatus designed for items of different weight.
As illustrated in FIG. 1, the adjustment mechanism comprises an anchor 3 which passes through a central opening 6 in a plate 4 against which the top of the spring 12 is urged. Projections 7 on the anchor 3 engage the underside of the plate and prevent the anchor from passing onward more than predetermined distances through the opening 6 in the plate 4. By twisting the anchor relative to the plate the projections 7 pass slots 10 in the plate 4 and it is possible to secure the relative height of the anchor and plate to each other and so to adjust the degree of compression of the spring 12 to diiferent loads.
The anchor 3 may be fixed by a thread connector -14 through the hole 15 to the carrier 9. The bottom of the anchor may be connected to the chain 11 by an eye 16. The constant of spring 12 can thus be readily adjusted to accommodate varying weights and items.
The described dispenser operates as follows:
When the device is empty, the carrier 9 occupies its uppermost position which is defined by the length of the chain 11. The user then places several items, plates and dishes in the illustrated example, on the carrier 9 between the guide bars 8. When the weight of the stack of dishes, for example four to six pieces, reaches and exceeds the pre-set value of the force exercised by the spring 12 on the carrier 9, the stack of dishes descends.
If the constant of the spring has been correctly set or chosen, then each time that the user places an additional dish or plate in the device, the support 9 will lower itself, through the effect of the weight of that item, by a distance corresponding to the thickness or the height of that item. In this manner, the dish or plate situated at the top of the stack resting on the support 9 is always situated at approximately the same level. In effect, the compression of a spring is substantially linear in relation to the load and the weight and geometrical shape of the dishes or plates may be considered as being approximately constant for the same type of dish or plate.
Should the movement of the carrier not be properly effected, adjustment of the spring constant is made by varying the position of the anchor 3 relative to the plate 4, until a satisfactory calibration is obtained.
In FIG. 3 the preferred form of anchor having stamped projections 7 at alternate right angles is shown;
FIG. 4 shows another embodiment in which alternating pairs of pins 7 act as anchor stops.
An indent 17 may be provided in the plate 4 to form a nest for the projections, which may comprise one or more elements simultaneously bearing against the plate 4. Although 90 alternation of the projecting stops 7 has been shown, other angles such as 30 or 60 are suitable and indeed all projections may be parallel if the anchor is rotated to lock in nests 17 at each step or stage.
While this invention has been described and illustrated with reference to a dispenser for plates and dishes, it is obvious that it may also be utilized for the storage and dispensing of industrial items and products. Other modifications of the invention may also be made.
What is claimed is:
1. In a self-leveling, storing and dispensing unit, which includes a housing, a helical compression spring mounted in said housing, and a carrier mounted on the upper end of said spring adapted to receive articles to be stored;
apparatus for adjusting the constant of said helical spring while the upper limit of travel of said carrier is maintained constant, comprising:
5 a plate mounted on top of said spring, said plate having a keyed passageway therethrough,
an anchor member depending from said carrier and adapted to pass through said passageway,
a plurality of non-contiguous projections mounted on said anchor, at least one projection being located at each of a plurality of spaced vertical positions therealong, indents formed in said plate securing said projections in a first position, the projections being operable to stop the upward movement of said plate urged by said spring when the projections at a given vertical position are in said first position, said projections at a given vertical position being adapted to pass through the keyed passageway in said plate at a second position which is radially removed from said first position, wherein the position of said plate may be externally rotatably adjusted to said one of a plurality of spaced vertical positions to thus vary the compression of the spring, and
the bottom of said anchor is connected to the bottom of said housing to limit the upward movement of the carrier as the constant of the spring is varied.
References Cited UNITED STATES PATENTS 2,226,308 12/1940 Gibbs 312-71 3,004,813 10/1961 Shivek 312-71 3,181,919 5/1965 Shelley 312-71 XR 3,190,453 6/1965 Shelley 312-71 XR 35 BOBBY R. GAY, Primary Examiner.
DAVID J. WILLIAMOWSKY, Examiner.
J. L. KOHNEN, Assistant Examiner.