Vending device with integrated inventory monitoring

A vending device has at least one display area and an evaluator. The display area is formed by a rigid body, and has at least two, spatially-separated product areas, the rigid body of the display area being held by force transmission areas of at least two weighing cells. The evaluator is configured to, at periodic intervals or when a total weight detected by the at least two weighing cells changes: determine new coordinates of a center of gravity from data of the weighing cells, and transmit the new coordinates to a controller. The controller is configured to: determine a product area within the display area based upon changes in the coordinates of the center of gravity, determine, from the change in a total weight, the weight of goods removed from or added to the determined product area, and update an inventory, stored in a memory, for the product.

CROSS-REFERENCE TO PRIOR APPLICATIONS

Priority is claimed to European Patent Application No. 18 000 719.7, filed on Sep. 6, 2018, the entire disclosure of which is hereby incorporated by reference herein.

FIELD

The present invention relates to a vending device with integrated inventory monitoring.

BACKGROUND

DE 100 45 516 A1 shows a sales counter for ice cream, wherein access to a specific ice cream container is determined by means of light barriers, and the number of sold ice cream scoops per type is deduced therefrom. Weight sensors which determine the total mass of the ice-cream container are also provided for each ice cream container.

SUMMARY

An embodiment of the present invention provides a vending device that has at least one display area and an evaluator. The display area is formed by a rigid body, and has at least two, spatially-separated product areas, the rigid body of the display area being held by force transmission areas of at least two weighing cells. The evaluator is configured to, at periodic intervals or when a total weight detected by the at least two weighing cells changes: determine new coordinates of a center of gravity from data of the weighing cells, and transmit the new coordinates to a controller. The controller is configured to: determine a product area within the display area based upon changes in the coordinates of the center of gravity, determine, from the change in a total weight, the weight of goods removed from or added to the determined product area, and update an inventory, stored in a memory, for the product.

DETAILED DESCRIPTION

Embodiments of the present invention provide a vending device that makes the sales process in the self-service area in a retail shop more efficient, and, in particular, monitors the inventory.

An embodiment of the present invention provides a vending device with integrated inventory monitoring. With the vending device, baked goods, vegetables, or fruit—in particular, for self-service sales—are offered in supermarkets or in specialty shops, for example. The vending device automatically determines the inventory of goods present in individual product areas. An embodiment of the invention further provides to a method for operating a vending device.

According to the invention, a vending device for, in particular, baked goods, fruit, or vegetables, consisting of at least one display area, is provided. The display area is formed by a rigid body. The display area includes at least two, spatially-separated product areas. The rigid body of the display area is held by the force transmission areas of at least two weighing cells. The vending device includes an evaluation unit which, at periodic intervals or when the total weight detected by the at least two weighing cells changes, is designed to determine new coordinates of the center of gravity from the data of the weighing cells. The vending device includes a control unit which is designed to determine a product area within the display area based upon changes in the coordinates of the center of gravity. The control unit is designed to determine, from the change in the total weight, the weight of the goods removed or added in the determined product area and to update the inventory. In one embodiment, the vending device is a vending device for self-service sales. In one embodiment, the vending device is a bread shelf for offering baked goods in a supermarket, from which the customer can take and package various baked goods from different shelf areas (product areas), paying for them later at the cash register. In one embodiment, the vending device is a shelf for fruit or vegetables that includes several product areas for different goods and offers them to the customer for taking them and later paying at the cash register. Common to all these devices is that, according to the prior art, when a certain good runs out or falls below a minimum number of units, an employee of the supermarket must be informed by a customer or must check the inventory at regular intervals in order to replenish in good time the goods which have fallen below a certain minimum number of units. The advantage of the invention is that the vending device automatically determines the inventory. In the context of the inventory monitoring of the vending device, an appropriate responsible person can then be prompted by the vending device to replenish the inventory.

In one embodiment, the vending device includes three or four weighing cells, which hold the rigid body of the display area. The person skilled in the art understands that these are three or four weighing cells per rigid body. If the vending device includes more than one display area with more than one rigid body, there is a corresponding number of weighing cells per rigid body.

In one embodiment, the control unit is designed to determine, from the total weight of goods removed or added and an average weight per good assigned to a product area, a count of goods removed or added.

In one embodiment, the control unit is designed to update the inventory within each product area based upon the removed or added goods.

In one embodiment, all weighing cells are periodically and simultaneously tared.

In one embodiment, the evaluation unit is designed to determine, when the total weight changes, a vector between the previous coordinates of the center of gravity and the new coordinates of the center of gravity. The evaluation unit is designed to determine a product area from the vector and the total weight. This product area corresponds to the product area from which the goods were removed or to which they were added.

In one embodiment, the vending device includes a memory in which appropriate product information, in particular, the weight per good/unit, is assigned to the product areas in the display area.

In one embodiment, the vending device includes a communications unit that sends or outputs a message when the inventory in a product area falls below a threshold value assigned to the product area. For example, the vending device may thus output a message with a display or a system light, which indicates to an operator that the inventory of a product is too low. On the other hand, the vending device can also send a message to a control room of the supermarket by means of e-mail or other electronic communication, which notifies an operator that the inventory of a product is too low. On the other hand, the vending device may also send a message to a baking oven, indicating, for example, the low inventory of a particular baked product and, possibly, automatically causing the baking oven to bake this baked product.

The invention further relates to a method for operating a vending device for, in particular, baked goods, fruit, or vegetables. The vending device includes a display area, wherein the display area is formed by a rigid body and wherein the display area includes at least two, spatially-separated product areas. The rigid body of the display area is held by the force transmission areas of at least two weighing cells. The method includes the step of receiving a signal of the at least two—preferably, three or four—weighing cells, wherein the signals correspond to the weight forces in the region of the corners of the rigid body. The method further includes the step of determining with an evaluation unit the coordinates of the center of gravity and a total weight force from the received signals. The method further includes the step of receiving a signal corresponding to a new weight force from at least one weighing cell and determining with the evaluation unit new coordinates of the center of gravity from the data currently received from the weighing cells. The method further includes the step of determining a product area and a weight of goods added to or removed from the product area. The method further includes the step of updating the inventory assigned to each product area.

In one embodiment, the method includes the step of periodically taring all the weighing cells. Furthermore, the method includes the step of determining new coordinates of the center of gravity and a new total weight with the new weighing data when the weight measured by at least one weighing cell changes.

In one embodiment, the method includes the step of determining new coordinates of the center of gravity with the new weighing data and the step of determining a vector between the previous coordinates of the center of gravity and the new coordinates of the center of gravity when the weight measured by at least one weighing cell changes. The method further includes the step of assigning a product area on the basis of the determined vector and the total weight. Furthermore, the method includes the step of determining the weight of the goods added to or removed from the assigned product area. Furthermore, the method includes the step of determining a count of goods based upon the weight of the removed or added goods and a weight per good/unit.

In one embodiment, the method includes the step of comparing the updated inventory in the assigned product area with a threshold value defined for the product area, and, if the updated inventory falls below the threshold value, the step of sending or displaying information that the threshold value has been undershot.

Some embodiments of the invention are shown by way of example in the drawings and are described in the following.

FIG. 1shows a vending device10according to an embodiment of the invention. The vending device10is suitable for self-service sales of, for example, baked goods, fruit and vegetables. The vending device10has a counter including a fixed frame11and a display area12. The display area12includes three product areas13,14,15in which various products (not shown) lie. The customers can take the products from the individual product areas, and package them and later pay at the cash register.FIG. 1shows, by way of example, a vending device with a display area12, which includes three product areas. However, the display area12may also include a higher number of product areas, which are arranged next to one another or, if appropriate, also in a matrix. The vending device can also include, for example, several display areas12, which are arranged one above the other, each of which in turn includes several product areas. Furthermore, each product area can also be closed on the front side or, for example, include a door which can be opened by the customer, as is known to the person skilled in the art from, for example, self-service devices for bread sales. The display area12itself or at least the bottom of the display area forms a rigid body. For example, the display area itself may consist of a rigid plate or be mounted on a rigid frame. The rigid body of the display area is supported by four weighing cells61,62,63,64, each of which is mounted near the corners of the display area and of which only the two front weighing cells62,63are shown inFIG. 1. The rigid body is respectively connected to the force transmission areas of the weighing cells61,62,63,64. The stationary sides of the weighing cells61,62,63,64are each mechanically fixedly connected to the frame11of the vending device. The weighing cells61,62,63,64are connected with their signal outputs to an evaluation unit (or evaluator)65. The frame11of the vending device carries a display16on which the inventory in the respective product areas is indicated and which serves to operate the vending device. The display is preferably designed as a touchscreen and can likewise be designed as a releasable tablet computer. The display can likewise be set up in a control room and communicate with the vending device via a network.

FIG. 2aschematically shows the display area of a vending device10according to the invention and the corresponding components for inventory monitoring. The product area from which a product was removed or to which a product was added is determined by determining the center of gravity of the rigid body60which forms the display area12.

The rigid body60is suspended from four weighing cells61,62,63,64. With their force transmission sides, the weighing cells61,62,63,64support the rigid body60at its corners or in the vicinity of the corners. The weighing cells61,62,63,64independently determine an effective weight force produced by the rigid body60and the products placed into the product areas. In this case, a single weight force acts on each weighing cell61,62,63,64in proportion to the total weight. The data from the weighing cells61,62,63,64are transmitted to an evaluation unit65. The evaluation unit determines coordinates of the center of gravity of the rigid body60from the individual weight data of the weighing cells61,62,63,64. The coordinates in the display area12start in a corner at the weighing cell63with the coordinates (0, 0) and extend in the horizontal direction X and in the vertical direction Y.

In order to illustrate the determination of the center of gravity, the corresponding weight data W61, W62, W63, W64are assigned to the weighing cells61,62,63,64, as shown inFIG. 2a.

The formation of the center of gravity in the X direction is determined as follows:
(W61+W62)/(W61+W62+W63+W64)

The formation of the center of gravity in the Y direction is determined as follows:
(W61+W64)/(W61+W62+W63+W64)

With a corresponding normalization factor, which takes into account the size of the rigid body60, coordinates in the display area corresponding to the coordinates of the center of gravity of the rigid body can be determined. These coordinates are determined in the evaluation unit65on the basis of the data of the weighing cells61,62,63,64. Furthermore, the evaluation unit65forms a total weight W61+W62+W63+W64. The coordinates of the center of gravity and the total weight are transmitted by the evaluation unit65to a control device (or controller or control unit)41. The vending device includes a memory44in which an assignment between coordinates of the center of gravity and product area13,14,15is stored. For each product area13,14,15, the average weight of a unit of a good in this product area is, moreover, stored in the memory44. Stored in the memory44for each product area13,14,15is the current inventory, i.e., the current number of goods/units in this product area13,14,15. With this arrangement, in addition to the product areas13,14,15shown inFIG. 1which are arranged next to one another in the X direction, it is also possible to determine product areas which are arranged in rows and columns in the X and Y directions, i.e., in a matrix.

FIG. 2bshows a system with two weighing cells62,63, with which system only the determination of a product area in the X direction is possible.

The formation of the center of gravity in the X direction is determined as follows:
(W62)/(W62+W63)

For a vending device as shown inFIG. 1, in which the product areas13,14,15are arranged next to one another in the X direction, such a system is sufficient.

FIG. 3shows a method for operating a vending device for, in particular, baked goods, fruit, or vegetables. In step30, the product areas13,14,15in the display area12of the vending device are loaded with goods. In the process, the good is assigned to each product area13,14,15, and a weight per unit is stored in the memory. This weight is the average weight per unit, since the weight of baked goods, for example, can differ slightly. However, the deviations are in a range and are statistically distributed such that they are not relevant for the method. Furthermore, the number of goods which are located in the product area after filling the vending device is stored in the memory44for each product area13,14,15. Furthermore, the X and Y coordinates of each product area13,14,15are stored in the memory44. These coordinates do not have to be newly stored with each filling, since they do not change. However, if the size of the product areas and their arrangement are changed by rearrangement of the intermediate walls, the assignment between X and Y coordinates and product areas13,14,15must be updated in the memory. It is thus stored in the memory over which X and Y coordinates each product area13,14,15extends. In addition, a threshold value for each product area is stored in the memory44; when this threshold value is undershot, the vending device outputs a message that fresh goods have to be replenished in this product area13,14,15. In step31, an evaluation unit65determines, from the weight values of the weighing cells61,62,63,64, a location where a good or goods were removed or added and the total weight of the removed or added products. The determination in step31can be carried out with two alternative methods, which are described below with reference toFIG. 4andFIG. 5. In step32, the control device41determines the assigned product area13,14,15on the basis of the coordinates of the location where something was removed or added and by means of the information from the memory44about the arrangement of the product areas13,14,15. In step33, the number of goods removed from or added to the product area13,14,15is determined from the determined total weight of the removed goods and the weight value for a good assigned to the product area13,14,15in the memory. The number of units removed is thus determined. In step34, the current inventory assigned to the product area13,14,15is reduced—if appropriate, increased—by the number of removed goods. The method is then continued with step30with the removal or addition of another good. Alternatively, the method may be continued with step35, in which a label is printed for the most recently removed good(s). The label is printed, for example, after a customer has completed his removals and they have been added up. The label can be printed for a single removal or as a sum label for several goods from several product areas. For example, the label may be glued by the customer onto a bag into which he placed his goods, and the label may serve as the basis for the payment process at the cash register. After printing the label, the method continues with step30. If a threshold value stored in the memory44for the inventory in a product area13,14,15is undershot, the method sends a message to an operator, in step36, so that he is informed that the inventory has reached a low level and has to be replenished. If the vending device is a vending device for baked goods, the message can also be sent to a baking oven, which then bakes the corresponding product automatically or as arranged by an operator. For example, the message sent in step36may automatically cause a baking oven to preheat and come to operating temperature, and be sent simultaneously to a mobile terminal of an operator to inform him that he is to load the baking oven with the corresponding product. In step37, new information about the inventory is entered by the operator, if he has replenished a product area with fresh goods. The information in the memory44about the inventory in this product area13,14,15is then updated accordingly, as prompted by the operator input.

FIG. 4schematically shows a method for determining a location in the display area12where a good was added or removed. In step71, all the weighing cells61,62,63,64are tared, i.e., the rigid body60and all of the goods placed thereon are treated as if they were a preload for the weighing cells61,62,63,64and are set to zero. In step72, a new weight value is measured by at least one weighing cell61,62,63,64and received by the evaluation device65. In step73, the evaluation device65calculates coordinates of the center of gravity on the basis of the current weight data of the weighing cells61,62,63,64. These coordinates of the center of gravity do not reflect the center of gravity of the rigid body60, but rather the center of gravity of the change in weight in the coordinate system of the display area12. This is the location where a good was removed from or added to the display area. In step74, this location and the change in weight are passed to the control device41.

FIG. 5schematically shows a method for determining a location on the display area12where a good was added or removed. In step81, the coordinates of the current center of gravity of the rigid body, including all of the goods placed thereon, are determined. This is the true center of gravity. The rigid body, or at least the goods placed thereon, are not tared. In step82, a new weight value is measured by at least one weighing cell61,62,63,64and received by the evaluation device65. In step83, new coordinates of the center of gravity are determined by the evaluation device65from the new data of the weighing cells61,62,63,64. In step84, a vector reflecting the shift in the coordinates of the center of gravity is formed from the previous coordinates of the center of gravity and the new coordinates of the center of gravity. Starting from the previous center of gravity, the vector leads to the new center of gravity unless the vector is scaled. In step85, the vector is, subsequently, inversely proportionally scaled with the aid of the total weight of the rigid body and the goods placed thereon. The location where a product was removed from or placed into the display area12results from step86, in which the scaled vector is added to the previous coordinates of the center of gravity. In step87, this location and the change in weight are passed to the control device41.

The functions of various elements shown in the drawings, including the functional blocks, may be realized by dedicated hardware, or by generic hardware capable of executing software in conjunction with the corresponding software. If the functions are provided by means of a processor, they may be provided by a single dedicated processor, a single shared processor, or several generic processors, which in turn may be shared. The functions may be provided, without limitation, by a digital signal processor (DSP), network processor, application-specific integrated circuit (ASIC), field programmable gate array (FPGA), read-only memory (ROM) with stored software, random access memory (RAM), and nonvolatile memories.