Disc Coin Sorter With Positive Guide Wall Between Exit Channels

1. Field of the Invention

The present invention relates generally to coin sorting devices and, more particularly, to coin sorters of the type which use a resilient rotating disc and a stationary sorting head for sorting coins of mixed denominations. The coin sorter of this invention is particularly related to coin sorting devices for coin sets in which there is only a small variation in diameters among the coin denominations.

2. Background Information

Although disc-type coin sorters with resilient discs have been used for a number of years, problems are still encountered in applying this technology to certain types of coin sets. Sorting heads for coin mixtures which include two coin denominations of substantially similar diameters may encounter difficulty in discriminating between coins of the different denominations. Because all coins to be sorted are usually aligned with their outboard edges at a common radial position and different denominations are discriminated by the distance of their inboard edges from that common radial position, coins of similar size must be precisely aligned at the common radial position in order to enter the appropriate exit channel. For example, a coin that moves just slightly beyond the common radial position may enter an exit channel intended for a smaller diameter coin. Rather than passing on to the appropriate exit channel, the larger denomination coin is issued from the exit channel intended for the smaller coin denomination. This is a coin missort.

It is a primary object of the present invention to provide an improved disctype coin sorter which is capable of accurately sorting coin mixtures which include coin denominations of substantially similar diameters.

It is another object of the invention to provide such an improved coin sorter which improves the accuracy of sorting a wide variety of different coin sets.

A further object of the invention is to provide such an improved coin sorter which can be efficiently and economically manufactured.

Other objects and advantages of the invention will be apparent from the following detailed description and accompanying drawings.

In accordance with the present invention, the foregoing objectives are realized by providing a disc-type coin sorter for sorting coin mixtures which include coin denominations of substantially similar diameters. The sorter has a rotatable disc having a resilient top surface, a drive motor for rotating the disc, and a stationary sorting head having a lower surface positioned parallel to the upper surface of the disc and spaced slightly therefrom. The lower surface of the sorting head is contoured to align the coins in a single file and single layer of coins, with a positive guide wall between exit channels to maintain the common radial alignment of coins as they pass between the exit channels.

FIG. 1 is perspective view of a coin sorter embodying the present invention, with portions thereof broken away to show internal structure;

FIG. 2 is a bottom plan view of the sorting head or guide plate in the coin sorter of FIG. 1;

FIG. 3 is a enlargement of the lower left hand portion of FIG. 2;

FIG. 4 is an enlarged section taken generally along line 4--4 in FIG. 3;

While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been shown by way of example in the drawings and will be described in detail. It should be understood, however, that it is not intended to limit the invention to the particular form described, but, on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.

Turning now to the drawings and referring first to FIG. 1, a hopper 10 receives coins of mixed denominations and feeds them through a feed opening in an annular sorting head or guide plate 12. As the coins pass through the feed opening (not shown), they are deposited on the top surface of a rotatable disc 13. This disc 13 is mounted for rotation on a stub shaft (not shown) and driven by an electric motor 14 mounted to a base plate (not shown). The disc 13 comprises a resilient pad 16 bonded to the top surface of a solid metal disc 17.

As the disc 13 is rotated, the coins deposited on the top surface thereof tend to slide outwardly over the surface of the pad due to centrifugal force. As the coins move outwardly, those coins which are lying fiat on the pad enter the gap between the pad surface and the sorting head 12 because the underside of the inner periphery of this plate is spaced above the pad 16 by a distance which is approximately the same as the thickness of the thickest coin. As further described below, the coins are sorted into their respective denominations, and the coins for each denomination issue from a respective exit channel, such as the channels 20, 21, 22, 23, 24 and 25.

In general, the coins for any given currency are sorted by the variation in diameter of the various denominations. Prior to sorting, the coins are manipulated between the sorting head and the rotating disc to queue the coins into a single-file, single-layer stream of coins. The outer edges of all the coins in this stream of coins are normally aligned at a common radius so that the inner edges of the coins can be engaged to discriminate among coins of different diameters, directing the coins to the desired exit slots for the respective denominations.

Turning now to FIG. 2, there is shown a bottom view of the preferred sorting head 12 including various channels and other means especially designed for high-speed sorting with positive control of the coins. It should be kept in mind that the circulation of the coins, which is clockwise in FIG. 1, appears counterclockwise in FIG. 2 because FIG. 2 is a bottom view. The various means operating upon the coins include an entry region extending around the entire inner periphery 30 of the sorting head, a queuing region which includes a spiral wall 40, and the exit channels 20-25 for six different coin denominations.

Considering first the entry region, the coins deposited on the rotating disc 13 directly beneath the feed opening are carried under the inner periphery 30 of the sorting head into an annular recess 31 extending around the entire circumference of the sorting head. Coins can move radially into the recess 31, which is spaced above the top surface of the pad 16 by a distance which is about the same as the thickness of the thickest denomination of coin.

Radial outward movement of coins within the recess 31 is terminated when they engage the outer wall 40, though the coins continue to be moved circumferentially along the wall 40 by the rotational movement of the disc 13. The outer wall 40 of the recess 31 extends down to the lowermost surface of the sorting head 12, which is preferably spaced from the top surface of the pad 16 by a distance, e.g., 0.005 inch, which is less than the thickness of the thinnest coin. Consequently, free radial movement of the coins is terminated when they engage outer wall 40, though the coins continue to move circumferentially along the wall 40 by the rotational movement of the pad.

At the end of the spiral wall 40, i.e., at the point where the spiral wall reaches its maximum diameter, the coins engage a ramp 41 which presses the coins downwardly into the resilient surface of the rotating disc. The outer edges of coins which engage the outer wall 40 have a common radial position and are ready for sorting. Coins whose radially outer edges do not engage the outer wall 40 engage a transverse wall 43 which guides such coins back into the entry recess 31 for recirculation.

It can occur that correctly aligned coins passing under the recycling wall 43 can be slightly shifted in their radial position. To correct this, coins which pass the recycling wall 43 enter a gaging channel 44 which allows the coins to be realigned against a radially outer wall 45. The channel 44 and wall 45 allow the coins in the sorting path an opportunity to realign their outer edges at the radial position required for correct sorting. To ensure that every coin engages the wall 45, the radius of the wall 45 from the center of the disc is gradually decreased along the length of the channel 44.

Downstream of the gaging channel 44, the sorting head 12 forms the series of exit channels 20-25 spaced circumferentially around the outer periphery of the sorting head. The downstream wall of each successive exit channel is located progressively farther away from the common radial location of the outer edges of all the coins for receiving and ejecting coins in order of increasing diameter. Because the outer edges of all coins are located at the same radial position, coins of the smallest diameter will be the only ones to be engaged by the downstream wall of the first exit channel. The exit channels extend outwardly to the periphery of the sorting head so that the downstream walls of the respective exit channel guide the coins outwardly and eventually eject those coins from between the sorting head 12 and the resilient pad 16.

In the illustrative coin sorter, which is intended for the Japanese coin set, the exit channel 21 is intended to discharge only Japanese 50-yen coins, and thus the downstream edge 21a of this channel is located at a radius that is spaced inwardly from the final radius of the gaging wall 45 by a distance that is only slightly greater than the diameter of a 50-yen coin. Consequently, only 50-yen coins can enter the channel 21. Because the outer edges of all denominations of coins are located at the same radial position when they leave the gaging channel 44, the downstream edges of all denominations other than the 50-yen coin extend inwardly beyond the downstream edge of the exit channel 21, thereby preventing these coins from entering.

At exit channel 22, the downstream edges of only the Japanese 5-yen coins are located close enough to the periphery of the sorting head 12 to enter the exit channel. The downstream edges of all the larger coins extend inwardly beyond the downstream edge 22a of the channel 22 so that they remain gripped between the sorting head 12 and the resilient pad 16. Consequently, all the coins except the 5-yen coins continue to be rotated past the exit channel 22.

Similarly, only Japanese 100-yen coins enter the channel 23, only 10-yen coins enter the channel 24, and only 500-yen coins enter the channel 25.

Missorting can occur in the region of the exit channels 20-25 when a coin mixture includes denominations of substantially similar diameters. Because the difference in the radial positions of the downstream guide walls of successive exit channels is equal to the difference in the diameters of the coins denominations to be issued by those channels, the downstream guide walls of adjacent exit channels are at closely spaced radial positions in a sorting head which processes coins of only slightly different diameters. For the exit channels to properly discriminate between such similarly sized coin denominations, all coins must have their outer edges precisely radially aligned to place their inner edges at the precise radii of the inboard ends of the downstream guide wall of the exit slots for those particular coin denominations.

When the coins traversing the exit channels are held in place solely by pressure between the sorting head and the pad, the positions of the coins may shift slightly outward as they cross the exit channels. Any outward movement of a coin equalling the difference between the diameter of that coin and the diameter of the next smaller coin will result in premature exiting of the shifted coin.

With American and Canadian coin sets, slight outward shifting of aligned coins held only by pad pressure is tolerable because pad pressure alone is sufficient to keep the radial movement of coins well within the required tolerance range. Coin sets of other countries, however, are more sensitive. The Japanese coin set, for example, consists of coins which can vary in diameter by as little as 0.015 of inch. Pad pressure alone is insufficient to reliably maintain the radial alignment of coins within the tight tolerances required by coin sets, such as the Japanese set, where the coin diameters are so similar.

The present invention alleviates the problem of outward movement of coins as they traverse the exit channels by providing a guide wall 60 for positive control of coins as they pass between exit channels. A coin of large diameter will pass the first exit channel 20 and be engaged by the positive guide wall 60 to maintain the coin at the desired radial position as it passes to the next exit channel. By positively maintaining the outer edge of the coin at the desired radial position, the possibility of a coin moving radially outward as it passes between exit channels is virtually eliminated.

The guide wall 60 is interrupted by the successive exit channels 21-25 but is continuous between each pair of adjacent exit channels. The shoulder 61 on the inboard side of the guide wall 60 intrudes slightly into each of the exit channels 21-25, but this shoulder 61 merely causes the exiting coins to tilt as they enter and travel along the exit slots. This tilting raises the leading edges of the coins into the exit channel, which is desirable for retaining the exiting coins within their respective exit channels.