Checkout system

Abstract: A method and apparatus for enabling a checkout system to repeat the price of a previously processed purchased merchandise item (84), includes mounting a pair of switch devices such as photodetector members (64,66) in a pair of apertures (48,50) located in the checkout counter (20) which is exposed to ambient light. The photodetector members (64,66) are enabled to generate a pair of control signals in response to positioning a finger (114) of the checkout operator over one of the apertures (50) and alternately covering and uncovering the second aperture (48) with a second finger (116) of the same hand of the checkout operator.

Description: This invention relates to checkout systems of the kind for processing purchased merchandise items having coded labels located thereon which contain coded indicia representing the identity of the respective merchandise items, including: support means having a transparent portion over which the coded label of a purchased merchandise item is moved; scanning means mounted within said support means and operable to project scanning light beams through said transparent portion for scanning the coded labels, said scanning means generating data signals in response to the scanning of said coded labels; a data terminal device connected to said scanning means; and processing means connected to said data terminal device and adapted to generate the price of the merchandise items scanned, in response to said data signals. (US-A-4,086,476). The invention also relates to a method for operating a checkout system. In order to increase the speed of checkout operations, optical scanning devices have been incorporated into checkout counters for reading data encoded indicia on labels affixed to the purchased merchandise items. Movement of the merchandise items across the scanning device results in the scanning device reading the encoded indicia labels. Where a number of the same merchandise items are being checked out, each merchandise item has to be moved across the scanning device in order to insert the merchandise item identification code into the processing system enabling the processing system to generate the price of the item. It has been found that this type of checkout procedure represents a significant portion of the total time it takes to check out the purchases of a customer. It is an object of the present invention to provide a checkout system of the kind specified whereby the speed of the checkout operation may be increased. Therefore, according to one aspect of the present invention, there is provided a checkout system of the kind specified, characterized by first and second manually operable switch devices mounted in said support member and adapted to provide first and second control signals to said scanning means whereby operation of said first switch device together with intermittent operation of said second switch device causes the provision of said first and second control signals, thereby causing repetition of the price of a scanned merchandise item. According to another aspect of the present invention, there is provided a method for operating a checkout system, including the steps of providing an optical bar code scanning means mounted in a checkout counter, scanning a coded label of a first purchased merchandise item, generating data representing the identification of the purchased merchandise item, and addressing a price lookup table to retrieve the price of the purchased merchandise item using the generated data as the address, characterized by the steps of: providing first and second manually operable switch devices mounted in said checkout counter; operating said first switch device to provide a first control signal and intermittently operating said second switch device to provide a second control signal; and utilizing said first and second control signals to repeat the price of a scanned merchandise item as the price of further merchandise items in response to the simultaneous generation of said first and second control signals. It will be appreciated that in a system and method according to the invention, a checkout operater can operate the switch devices using the fingers of one hand, while moving merchandise items into or towards a receptacle with the other hand, thereby increasing the speed of the checkout operation since individual identical items need not be scanned. One embodiment of the invention will now be described by way of example, with reference to the accompanying drawings, in which:- Fig. 1 is a perspective view of a checkout system in which the present invention is incorporated; Fig. 2 is a schematic diagram of the bar code reader which includes the photodiodes and the microprocessor; Fig. 3 is a fragmentary perspective view of the mechanical elements of a bar code reader; Fig. 4 is a block diagram of the checkout system which utilizes the present invention; Fig. 5 is a partial side sectional view of the apertures located in the top surface of the checkout counter; Fig. 6 illustrates waveforms useful in explaining the operation of the present invention; and Fig. 7 is a schematic diagram of the circuit enabling the silicon photodiodes to generate digital signals in accordance with the light level striking the photodiodes. Referring now to Fig. 1, there is shown a perspective view of a checkout system which includes a checkout counter 20 having a top surface 22 on which are positioned the purchased merchandise items of a customer. Located at one end of the top surface 22 is the top surface plate 24 of an optical bar code reader 26 mounted within the counter 20. Located in the top plate 24 of the bar code reader 26 is a star-shaped window 28 through which scanning light beams from the reader are projected to scan a bar code pattern on a label attached to a purchased merchandise item moving across the window 28. Located adjacent the top plate 24 are a pair of upstanding rail members 30, 32 in which are mounted light emitting diodes 35, 37 (Fig. 3) and photodetectors 34, 36 (Figs. 1 and 3) forming item gates for sensing the presence or absence of a merchandise item on the top surface plate 24 for use in controlling the operation of the bar code reader 26. Mounted adjacent the counter 20 is a support member 40 on which is located a data terminal device generally indicated by the numeral 42 which includes a display portion 44 and a keyboard portion 46. As is well known in the art, coded data generated by the bar code reader 26 in reading a coded label attached to the purchased merchandise item is used to look up, in a price look-up table in a remote processor, the price of the merchandise item being scanned. This information is then transmitted to the display portion 44 enabling the operator and the customer to observe the price of the merchandise item being processed and then stored in a microprocessor 56 (Fig. 2) in the bar code reader 26. If additional information is to be inserted into the terminal, the keyboard portion 46 is utilized for this purpose. Located adjacent the rail member 32 and window 28 in the top surface 22 of the counter 20 are a pair of apertures 48, 50 which are used in the present invention in a manner to be described more fully hereinafter. Referring now to Fig. 4, there is shown a block diagram of the checkout system which includes the bar code reader 26 coupled over a communication link 49 to the point of sale (POS) data terminal device 42 which in turn is coupled over a communication link 51 to a remote processor 52 in which are located the price look-up tables (not shown) from which the price of the merchandise item being processed is recovered utilizing the encoded data read from the coded label on the scanned merchandise item. The numerical data representing the price of the purchased merchandise items is then transmitted from the processor 52 and over the communication link 51 to the terminal device 42, which stores the price data and prints the price on a receipt and displays the price on the display portion 44. Referring now to Fig. 2, there is shown a block diagram of the bar code reader 26. The reader includes a scanner assembly 54, a microprocessor 56 for checking and decoding the encoded data read by the scanner assembly 54, a conventional memory storage unit 58, an output buffer 60 utilized for transmitting the data read by the scanner assembly 54 over the communication link 49 to a processor unit (not shown) in the POS terminal unit 42 (Figs. 1 and 4), an item gate unit 62 which includes an upstream 34 (Fig. 1) and a downstream 36 item gate for detecting the presence or absence of a merchandise item on the top plate 24 of the bar code reader 26 for controlling the operation of the bar code reader, a pair of photocells 64, 66 used to control the microprocessor in processing the encoded data read from the purchased merchandise item in a manner that will be described more fully hereinafter and light indicators 70. Referring now to Fig. 3, there is shown a perspective view of the mechanical structure of the scanner assembly 54 (Fig. 2) which includes a light source 70 emitting an optical light beam 72 in the visible or near visible spectrum, the light beam 72 being focused by a lens system 74 onto a multi-faceted mirror 76. The mirror 76 is secured to the shaft 78 of a motor 80 which rotates the mirror 76 at a substantially constant speed. The rotating mirror 76 projects the light beam 72 through the window 28 located in the top surface plate 24 of the bar code reader to scan the encoded indicia on a label 82 attached to a purchased merchandise item 84 positioned adjacent the window 28. The rotation of the mirror 76 results in a succession of light beams 72 forming a scanning pattern which scans the encoded label 82 in a manner that is well known in the art. The scanning light beams 72 are reflected off the label 82 through an optical filter 86 to a photo-responsive detector device such as a photo-multiplier 88 which converts the reflected light beams into electrical signals, the amplitude of which corresponds to the amount of light received. The electrical signals are then converted to digital signals and transmitted to the microprocessor 56 (Fig. 2) which processes the encoded data, transmits the data through the output buffer 60 to the terminal device 42 (Fig. 4) which in turn transmits the data to the remote processor 52 where the data is used by the processor to look up in lookup tables the price of the purchased merchandise item. The microprocessor 56 will also decode and check the encoded data received from the photomultiplier 88 to determine if the data is valid or not and will then generate control signals indicating whether the scanning operation produced a good or bad read. The microprocessor 56 will transmit such signals to the light indicators 70 (Fig. 2) which are operated to indicate to the operator of the terminal device whether a good or bad read operation was obtained. If a bad read operation is indicated, the operator will then repeat the movement of the purchased merchandise item across the window 28. Referring now to Fig. 5, there is shown a partial side sectional view of the top surface 22 of the checkout counter 20 (Fig. 1) which includes the apertures 48 and 50. Each of the apertures 48 and 50 extend through the top surface 22 of the checkout counter and includes a floor member 90 in which is mounted one of the photocells 64 and 66 (Fig. 2) which may comprise silicon photodiodes. When the aperture 48 and 50 are uncovered, the ambient light from a light source such as a fluorescent lamp striking the silicon photodiodes results in the generation of electrical signals having a first value. When the apertures 48 and 50 are covered, the reduction in the intensity level of the light striking the silicon photodiodes located in the apertures 48 and 50 results in the generation of electrical signals having a second value. If it is desired to repeat the price of a scanned merchandise item, the operator will cover the aperture 50 with a finger 114 resulting in the photodiode 66 generating an enable signal 92 (Fig. 6) which is transmitted to the microprocessor 56. As each succeeding purchased merchandise item being processed is found to be the same, the operator will use another finger such as the forefinger 116 to intermittently cover and uncover the aperture 48 thereby producing a series of count signals 94 in accordance with the number of merchandise items processed. The occurrence of each of the count signals 94 during the time the enable signal 92 is generated results in the microprocessor 56 signalling to the data terminal device 42 that the price of the scanned merchandise item scanned is to be repeated. It will be seen that this operation can be performed with one hand while leaving the other hand of the operator free to place the purchased merchandise items in a proper receptacle. This operation also eliminates a large portion of the checkout procedure thus shortening the checkout operation. Referring now to Fig. 7, there is disclosed a schematic diagram of the control circuit associated with the photodiodes 64, 66 which will convert a change in the light level striking the silicon photodiodes 64 and 66 to digital signals which can be used to control the microprocessor 56 to repeat the price look-up operation of the previously processed merchandise item. The diode 95, which may be either of the photodiodes 64 or 66, produces an electrical current from a voltage source 93 in proportion to the amount of light striking its active element in a manner that is well known in the art. This current is converted by the amplifier 97 into a voltage signal which is applied across timing elements comprising resistors 96 and 110 and capacitors 98 and 102. The RC time constants are chosen so that the resistor 110 and capacitor 102 track long term changes in the order of ten seconds and apply said changes as a reference voltage level over line 104 to the positive input of the amplifier 106. Timing elements resistor 96 and capacitor 98 are chosen to respond to fast changes in the order of ten milliseconds and the corresponding voltage level is applied over line 108 to the negative input of the amplifier 106. The amplifier 106 is a voltage comparator that produces a low level output when the input voltage level on line 108 is positive with respect to the voltage appearing on line 104 and produces a high level output when the voltage level appearing on line 108 is negative with respect to the voltage level appearing on line 104. A voltage divider comprising resistors 96 and 100 will establish a quiescent level at the negative input of the voltage comparator 106 which will be more positive than the voltage level appearing on line 104 as determined by the voltage divider comprising the resistors 110 and 112. This condition will cause the output of the voltage comparator 106 to be normally at a low signal level which will be maintained for slowly varying light change. When an object such as a finger is moved over the photodiode 95, the light striking the diode is decreased and the resulting voltage level appearing at the negative input of the voltage comparator 106 will become more negative. This action will cause the voltage level appearing on line 108 to become more negative than the slowly changing voltage level appearing on line 104, which will cause the output of the voltage comparator 106 to switch to a high level digital signal. This high level digital output of the voltage comparator 106 can be used as a logic signal to represent the presence or absence of an item over the scanner. This type of circuit operates in a photoconduction mode and allows automatic correction for slow changes in ambient light levels. The output signals of the photodiodes 64 and 66 are transmitted over line 67 to the microprocessor 56. Although in the preferred embodiment switch devices including photocells 64, 66 mounted in apertures 48, 50 and responsive to ambient light are utilized, it should be understood that other constructions of switch device mounted in the counter 20 could be utilized. For example each switch could include a light source providing light which can be reflected from an operator's finger to energize a photocell, or the switches could be electro-mechanical switches operated by finger pressure or movement.

Claims: A checkout system for processing purchased merchandise items (84) having coded labels (82) located thereon which contain coded indicia representing the identity of the respective merchandise items (84), including: support means (20) having a transparent portion (28) over which the coded label (82) of a purchased merchandise item (84) is moved; scanning means (54-62) mounted within said support means (20) and operable to project scanning light beams (72) through said transparent portion (28) for scanning the coded labels (82), said scanning means (54-62) generating data signals in response to the scanning of said coded labels (82); a data terminal device (42) connected to said scanning means (54-62); and processing means (52) connected to said data terminal device (42) and adapted to generate the price of the merchandise items (84) scanned, in response to said data signals, characterized by first and second manually operable switch devices (66, 64) mounted in said support member (20) and adapted to provide first and second control signals (92, 94) to said scanning means (54-62), whereby operation of said first switch device (66) together with intermittent operation of said second switch device (64) causes the provision of said first and second control signals, thereby causing repetition of the price of a scanned merchandise item (84). A checkout system according to claim 1, characterized in that said first and second switch devices include respective first and second photodetector means (66, 64) mounted in said support means (20) adjacent said transparent portion (28), said first photodetector means (66) generating said first control signal (92) when prevented from receiving ambient light and said second photodetector means (64) generating said second control signal (94) when intermittently receiving ambient light. A checkout system according to claim 2, characterized in that said support means (20) includes first and second apertures (50, 48) positioned adjacent said transparent portion (28), said first photodetector means (66) being mounted in said first aperture (50) and said second photodetector means (64) being mounted in said second aperture (48). A checkout system according to claim 3, characterized in that said first control signal (92) is generated by said first photodetector means (66) in response to the placing of a first finger (114) over the first aperture (50), and said second control signal (94) is generated by said second photodetector means (64) in response to the sequential placing of a second finger (116) over said second aperture (48) and the removal of said second finger (116) from said second aperture (48). A method for operating a checkout system, including the steps of: providing an optical bar code scanning means (54-62) mounted in a checkout counter (20); scanning a coded label (82) of a first purchased merchandise item (84), generating data representing the identification of the purchased merchandise item (84), and addressing a price lookup table to retrieve the price of the purchased merchandise item using the generated data as the address, characterized by the steps of: providing first and second manually operable switch devices (66, 64) mounted in said checkout counter (20); operating said first switch device (66) to provide a first control signal (92) and intemittently operating said second switch device (64) to provide a second control signal (94), and utilizing said first and second control signals (92, 94) to repeat the price of a scanned merchandise item (84) as the price of further merchandise items in response to the simultaneous generation of said first, and second control signals (92, 94). A method according to claim 5, characterized in that said first and second switch devices include respective first and second photodetector means (66,64) responsive to ambient light, mounted in respective first and second apertures (50,48) in said support means (20), in that said step of operating said first switch device (66) includes the step of covering said first aperture with a first finger (114) and in that said step intermittently operating said second switch device (64) includes the step of repeatedly covering and uncovering said second aperture (48) with a second finger (116).

Inventors: BLANFORD DENIS MICHAEL, COLLINS DAVID ALEXANDER JR, MERGENTHALER BARRY MYRON, BLANFORD, DENIS MICHAEL, COLLINS, DAVID ALEXANDER, JR., MERGENTHALER, BARRY MYRON
Applicants: NCR INT INC, NCR INTERNATIONAL INC.
Application year: 1989
Main classification: G06K7
IPC codes: G07G1, G06K7