GB2288245A

GB2288245A - Electronic weighing apparatus

Info

Publication number: GB2288245A
Application number: GB9507269A
Authority: GB
Inventors: Neil James Hunter
Original assignee: IMS Innovation Ltd
Current assignee: IMS Innovation Ltd
Priority date: 1994-04-07
Filing date: 1995-04-07
Publication date: 1995-10-11
Also published as: GB9507269D0; GB9406875D0

Abstract

An electronic weighing apparatus comprises means 1 and 2 for providing an electronic signal corresponding to the weight of an article and processing means 3 for calculating a result from the signal using data stored in a memory and also has a magnetic card reader 6 arranged such that the data stored in the memory may be varied by reading magnetic cards with the card reader. The memory may contain postal rates or the data necessary to count cash by weighing.

Description

WEIGHING APPARATUS This invention relates to electronic weighing apparatus but is particularly applicable to postal scales and cash counting scales.

It is known to use weighing scales in order to count articles of known weight, determine their value from a given cost per unit weight or to calculate data related to the weight of one or more articles such as the cost of postage. These calculated data are obtained using calibration constants which may be varied from time to time, eg. cost per kilogram or in the case of postage rates cost per gram and cost per distance or postal method. It may also be desirable to provide further data which relate to the environment in which the apparatus is employed, for example a gravity calibration correction.

It is generally desirable to be able to vary these calibration constants or other data stored in the apparatus. Conventionally, this is achieved by changing a computer program resident in an EPROM memory provided in the apparatus or by setting switches or other internal adjustments. Such operations may require the use of skilled personnel and may require the apparatus to be partially dismantled. They therefore tend to be expensive and inconvenient for the user.

According to the invention there is provided an electronic weighing apparatus comprising means for providing an electronic signal corresponding to the weight of an article and processing means for calculating a result from the signal using data stored in a memory, wherein the weighing apparatus further comprises a magnetic card reader arranged such that the data stored in the memory may be varied by reading magnetic cards with the card reader.

Such changes may be easily and quickly made by a user of the machine having no technical expertise.

Furthermore, cost savings are made compared to prior art devices as the paper or plastic card is of lower cost than replacement memory devices. Savings are also made as the unskilled user of the machine is able to carry out the update without expensive technical assistance.

The system can also produce cost savings as a result of the ease of automating the production of the magnetic update cards compared to the cost of supplying new integrated circuits, or re-writing EPROMs.

Thus, the invention reduces the cost and complexity of carrying out changes to stored data by using a paper or plastic magnetic card which carries the new calibration information coded within the magnetic stripe.

Preferably the apparatus is arranged such that pulling the magnetic card past a reading head transfers the information into non volatile memory within the weighing machine.

Instructions for the user may be provided in the form of a handbook, and/or simplified instructions may be printed on the body of the apparatus. However, since electronic weighing apparatus are generally provided with a display unit (eg. of LCD type) this display may be used to relate to the user the correct method of operation of the apparatus when being updated.

As it is possible that data may not be fully or correctly read by the card reader, for example because data on a magnetic card has become corrupted, it is preferred that the apparatus be provided with a system which checks the data for integrity and completeness.

In order to alert a user to such a problem, the apparatus may be provided with means of indicating to the user that an unsuccessful data read has occurred.

For example a message may be provided on a display unit, or an audible tone may be used. The apparatus may be arranged such that it cannot be used until a correct data entry has been made.

Although it is possible to use motor-driven cardreaders, their cost and complexity is generally not justified in view of the comparatively infrequent use expected in the present invention. Consequently, the use of a manual "swipe" type card reader is preferred.

Although this type of card reader is generally reliable, one problem which exists is that it is important for the card to be "swiped" past the head of the correct speed. If the card is swiped too quickly or slowly, then the data may not be read correctly.

Preferably, therefore, the apparatus provides an indication of the speed at which a card is swiped past the head. This may be provided during the swiping operation, but it is believed to more useful if provided after each card has been swiped. The speed of card movement may be prevented on the display as a number, e.g. from 1 to 99 or simply as "correct", "too fast" or too slow". In the latter case, simple graphical symbols (e.g. arrows) may be used.

One effective method of calculating the speed of the card is to compare regularly spaced coded signals on the card with the clock-pulse of the apparatus. The cards employed may be of the well known credit card format or the larger "airline" style. The latter are much larger and can hold up to 0.5K Bytes of data on three tracks. This may be useful if a complex postal tariff is to be stored which would otherwise require a large number of smaller cards. The longer magnetic strips provided on these cards make the swipe-speed displaying arrangement discussed above particularly applicable when they are used.

As certain data, such as postage rates, is likely only to be valid for a certain time, preferably the machine will not accept old outdated data and will have means of recognising the validity of the data. For example, magnetic cards may be provided with additional data indicating an expiry date and the apparatus may be arranged to recognise when that date has passed, and will reject data from the out-of-date card. The machine may, therefore be further provided with means to enter the date into memory.

An embodiment of the present invention will now be described, by way of example only, and with reference to the accompanying drawing, Fig. 1, which is a schematic block diagram of a weighing device according to the present invention.

The weighing machine shown generally at 1 comprises, in a simple form, a weighing transducer 1, an analogue to digital convertor 2, a microprocessor 3, a memory 4 and a non volatile memory 5. Magnetic read heads 6, display 7 and keyboard 8 are also provided.

The apparatus is controlled by the microprocessor 3 which runs a program stored in memory. In order to change stored data, the user enters a button sequence at keyboard 8 which is read by the microprocessor 3 which switches the apparatus into data-entry mode. The user then pulls a magnetic card past the read head 6. The microprocessor 3 then translates and checks the data for integrity and validity and stores it in memory 5.

In practice it may be necessary to use more than one card in the updating sequence since there is a limitation of memory storage available on one card. If this is the case then these steps are repeated until the full set of data has been entered.

If a card is unreadable for any reason, this is indicated to the user on the display 7. The speed at which the card is swiped past the magnetic head 6 is calculated from pulses produced by the swiping operation being compared to a clock pulse by the microprocessor 3.

The result of this is also displayed on Display 7.

Consequently, if the card was unreadable due to an incorrect swiping speed, the user will be made aware of this.

When the operation is completed, the successful outcome of the updating is indicated on the display 7 and the weighing machine is returned to normal weighing and price computing mode but the new calculating data is used for future calculations.

In this mode, an item on the weighing transducer 1 produces an analogue signal which is fed to analog-todigital convertor 2. The resultant digital data is then used by microprocessor 3 to determine the weight of the item. Further data input via keyboard 8 (e.g. regarding the destination of the item) is then used by the microprocessor 3 to calculate the required postage.

Further features together with various modifications or improvements can be made without departure from the scope of the invention.

Claims

CLAIMS:

1. According to the invention there is provided an electronic weighing apparatus comprising means for providing an electronic signal corresponding to the weight of an article and processing means for calculating a result from the signal using data stored in a memory, wherein the weighing apparatus further comprises a magnetic card reader arranged such that the data stored in the memory may be varied by reading magnetic cards with the card reader.

2. Apparatus as claimed in claim 1, wherein pulling a magnetic card past a reading head transfers information into non volatile memory within the weighing machine.

3. Apparatus as claimed in claim 1 or 2, wherein the apparatus has a display unit which is used to relate to the user the correct method of operation of the apparatus when being updated.

4. Apparatus as claimed in any preceding claim, further provided with a system which checks the data for integrity and completeness.

5. Apparatus as claimed in any preceding claim, further comprising means of indicating to the user that an unsuccessful data read has occurred.

6. Apparatus as claimed in any preceding claim, wherein the apparatus cannot be used until a correct data entry has been made.

7. Apparatus as claimed in any preceding claim, further comprising means for detecting cards which have passed their expiry date.

8. Apparatus as claimed in any preceding claim wherein a manual card reader is employed.

9. Apparatus as claimed in any preceding claim, further comprising means for determining whether a card has been moved past the card reader at a pre-determined speed.

10. Apparatus as claimed in claim 9, wherein the speed determining means comprises means to read signals derived from the card and to compare their frequency with a regular clock pulse produced by the apparatus.