GB2074739A - Weighing apparatus - Google Patents

Abstract

Weighing apparatus particularly in the form of shop weighing scales comprises a spring balance 10 electrically connected by lead 11 to an electronic evaluator 20 having tabulator keys 21, 22, and a display section 23 to display weight, price per unit and the corresponding price of a weighed article 16. To render balance 10 universal for connection to any evaluator 20 the balance is provided with a control element 30 conveniently in the form of an electronic data memory having an output lead 19 feeding through lead 11 to evaluator 20 and containing technical data designating the particular spring balance 10, for example maximum permissible weight, the sensitivity of the balance and maintenance data such as last inspection date. The evaluator 20 is programmed to accept weight-derived signals directly from balance 10 and signals from control element 30 to compute and display in window 24 the weight and to compute and display in window 26 the price of article 16. Display section 23 further includes window 28 wherein there is permanently displayed selected items of the technical data contained in control element 30. <IMAGE>

Description

SPECIFICATION Weighing apparatus This invention relates to weighing apparatus.

Weighing apparatus, especially a shop weigh ing scales may comprise a spring balance with weighing pan and an evaluator connectable thereto for the purpose of determining the weight of the goods and with indicator win dows to display, in particular in digital form, the weight obtained and possibly also the prices of the goods. This information is fed in through a keyboard or the like forming part of tthe evaluator as load-specific information, such as a basic price, and/or may be calcu lated by way of the weight obtained such as the individual sales price of the goods, and usually specific information concerning the technical data of the spring balance, such as its maximum and minimum permissible weights, its unit of calibration, model number and the like, is displayed at the evaluator.

There are regulations according to which every weighing scales must carry details of the specific technical characteristics of the spring balance. These details normally appear on a plate securely affixed to the scales and include such production information as model number and year of manufacture. In order that the customer can check the proper use of the scales in respect of the maximum and minimum permissible weights and also the accuracy with which the scales indicates the weights and prices, this information should also be easily visible to the customer, for which reason it has been shown at the evalua tor in the field of view of the customer.

However, for each spring balance of a particu lar type, an evaluator of special construction was allocated which was adapted thereto. For each model of a weighing scales, which dif d from another model, for example, only oy t different effective weight range, it was necessary to develop a suitable evaluator. For a sales or repair-exchange service, it was necessary to stock a correspondingly compre hensive range of the various evaluators.In the case where the spring balance formed a unit separate from the evaluator, but connected up by an electrical coupling on its connecting lead, the particular coupling halves of differ ent types of balances and evaluators had to be constructed differently from each other in order reiiably to exclude the possibility of wrong connections occuring between incom patible types.

The object of the present invention is to develop weighing apparatus in which it is no longer necessary to distinguish between vari ous types of spring balances and evaluators, whilst at the same time every spring balance of a certain type is given the appropriate evaluator and the technical data of the spring balance is also easily visible to the customer.

According to the present invention there is provided weighing apparatus comprising a spring balance with weighing pan for the purpose of determining the weight of the goods, and an evaluator with indicator windows to display the weight obtained whilst specific information concerning the technical details of the spring balance connected thereto is contained in a control element and the evaluator is provided with elements which receive this information of the technical details of the spring balance, which firstly, take into account this technical information automatically, together with the weight-related measurement signals emanating from the spring balance, when determining and displaying the weight of the goods, and secondly, indicate these technical details in indicator windows.

In this way, it is possible to allocate a given evaluator immediately to a large number of spring balances of the most varied kinds. By virtue of the specific data memory or memories it contains, every spring balance ensures by itself that the evaluator connected thereto is informed as to the the exact kind of model which is connected to it, whereupon the evaluator takes this automatically into account in the measurement signals which it receives, and in each case indicates the correct weights and prices (if appropriate). At the same time, the evaluator uses this information to display the specific technical details of the spring balance preferably in digital form in special indicator windows, so that this information is as conveniently available to the customers as the other indications such as weight, basic price and individual price of goods.These various indicator windows are preferably located in one display region in the upper part of the evaluator, where they can be easily read both from the assistant's side and from the customer's side of the instrument. There is no longer any necessity for a particular selection or for any form of adaptation in connecting any given spring balance to an evaluator. The data memory or memories characteristic of the spring balance are conveniently attached to the same connecting lead by means of which the measurement signals of the spring balance are already being transmitted to the evaiuator. Simply by connecting the spring balance thereto, the specific data relating to the balance is received by the evaluator, whereupon the evaluator automatically adapts its manner of working and display to said data.In this way, for a wide range of the most varied spring balances, one'evaluator of one single standard type is required, whereby there is a considerable reduction in the manufacturing costs and in the range of evaluators requiring to be stocked. Thus, a given evaluator can co-operate with any spring balance without any risk of faults or errors occuring in determining and displaying values. This also alleviates considerably the work of the repair services, since a defective spring balance can be immediately replaced by any other spring balance available.

In addition to specific technical data relating to spring balances, such memory or memories may also contain further individual information relating to the spring balance. These data memories may be integrated into the spring balance in any desired position. Instead of locating it in the casing, it may be incorporated into the electrical coupling half at the end of the connecting lead, for example, in the form of an electric plug. Electronic data memories are in fact so tiny that they can be conveniently contained in the body of an electric plug.

The data memories in the spring balance may contain the most varied information concerning its characteristics. Apart from structural data, such as maximum or minimum permissible weight for the spring balance and the sensitivity of the balance, they may also contain specific maintenance data of the particular spring balance. Such additional data may be unchanging, for example, the production number of the instrument and its date of manufacture. It is also quite possible to store variable in ormation which is applicable only periodically to the balance, such as the next inspection date or the last repair date.

Two embodiments of the invention will now be described by way of example with reference to the drawings, in which: Fig. 1 is a side elevation view, partly cutaway, of weighing apparatus; and Figure 2 shows a detail of another embodiment of the weighing apparatus partly in section and partly cut-away.

Referring now to Fig. 1, the weighing apparatus comprises a spring balance 10, in this case constructed as a separate unit, and an electronic evaluator 20 linked thereto by a connecting lead 11. If two units are employed which can be installed separately from each other, this connection includes a plug and socket coupling, which can be seen at the end of the connecting lead 11 where the plug-type coupling half 1 3 can be seen which co-operates with a complementary coupling half in the casing of the evaluator 20, into which it is inserted. As indicated by the chain-dotted line 12 in Fig. 1, the two component parts of the weighing apparatus, the spring balance 10 and the evaluator 20, might be accommodated in a common housing.In this case, the connecting lead 11 is merely and ordinary electrical lead which is connected to the evaluator part in any suitable manner, for example by ordinary terminal connections.

The spring balance 10 comprises a weighing pan 1 5 on which the article 16 to be weighed is placed, and beneath which is an instrument casing 14 in which the spring balance box 1 7 (shown diagrammatically) is fitted, which may be of any suitable kind, e.g.

with vibrating strings or elastic extension strips. The weight of the article 1 6 is transferred mechanically to the weighing mechanism within the box 1 7 by way of an input member 50 (shown only diagrammatically), whereupon a weight-related signal is conveyed via an electrical lead 18 to the connecting lead 11. Data memories 30 are integrated into the spring balance 10, in this case, securely built into the casing 14 of the spring balance 10, so that they are inaccessible to unauthorised persons.These data memories 30 transfer information by way of an electrical lead 1 9 to the connecting lead 11, through which the information, together with the measurement signals of the spring balance box 1 7, are passed to the evaluator 20 via the plug and socket coupling 1 3.

In the present case, the embodiment is of a price-computing weighing apparatus in which the evaluator 20 has a keyboard 21 for feeding in a price per kilogram, and also various selective keys 22 which are designed and operate in the conventional manner. Apart from a computer for the incoming measurement signals and technical information signals, the evaluator 20 also has a comprehensive display region 23 which is located not only on the assistant's side of the evaluator 20 which carries the keyboard 21, but also on the opposite or customer's side (not visible in Fig. 1) at least in respect of the indicator windows mentioned below. Each display is preferably in digital form, for which purpose a conventional electric segment portrayal of numbers is employed.In a first indicator window 24, from the measurement signals and technical information signals fed in through the connecting lead 11, the individual weight of the article 1 6 is shown. Beside it is a further indicator window 25 which displays the basic price entered by way of the keyboard 21. In an adjacent window 26 the sales price is displayed, which is obtained from the normal calculator provided in the evaluator 20 on the basis of the data shown in the indicator windows 24 or 25, said sales price in the present case being given in the currency "DM". A further small window 27 may be provided for tare weight. A zone 28 may also be provided in the display region 23 which shows in segmental representation the specific technical data of the spring balance 10 in digital form, which is described in detail with reference to the embodiment of Fig. 2.

Referring once more to Fig. 1, in the display region 23, further display elements may be provided, which are located only on the assistant's side, for example, window 35 for a keyed-in code number of a so-called ''price look-up", in which case complete sales prices are stored in a memory of the evaluator, which can be called up by operation of the keyboard 21 following the series of digits in the code number, and then appear immedi ately as basic prices or individual prices in the indicator window 25 or 26.

The windows 36, 37 placed one on each side of this price look-up indicator 35 give the items in a sales transaction which are rec orded by two different sales assistants em ploying the scales simultaneously. By operat ing in the normal way the selective keys 22 allocated to them the two assistants are able to register which of them is carrying out the next sales operation. Signal lamps 38, 39 'located above indicate which of the two assis tants is serving from the scales at that mo ment. A further signal lamp 40 is illuminated when the entry of a tare value is made, which then appears in the above mentioned indicator window 27.Further signal lamps 41, 42, 43 indicate the state of the battery, the end of the paper supply of a printer (not shown) or the summation of a sales transaction compris ing a series of items, which were counted item by item, for example in the aforemen tioned windows 36 or 37 and now appear as a total amount in the indicator window 26, whilst being possibly printed on a cash-slip in the printer. A last signal lamp 44 may indi cate the fixed setting of the evaluator.

Referring now to the diagrammatic detail view in Fig. 2, the particular manner of work ing of the invention is shown with reference to another embodiment. This embodiment dif fers from that of Fig. 1 in that the aforemen tioned data memories 30 are accommodated within the body of the coupling half 1 3 on the spring balance side, which forms the extre mity of the connecting lead 11. The coupling half 1 3 comprises a series of plug pins 45, opposite which are seen the corresponding terminal sockets 46 contained in the other coupling half 47 mounted in the casing of the evaluator 20.Whilst some of the plug pins transmit the measurement pulses from the .ring balance box 1 7 directly through the aror-.=mentioned electrical lead 18, other pins have connected to them the data memories 30 which, as indicated by the three compart ments, convey in he present case three items of information which occur, of course, in ;coded form but are shown here for the sake of simplicity as the memory portions 51, 52, 53.

This information is conveyed in the form of electrical pulses via the plug 1 3 and socket 47 to the evaluator 20 where it is relayed by leads 48 to a receiver 29 (shown diagramma tically) which decodes it, employs it in con junction with the weight-related measurement signals conveyed thereto in calculating the exact weight value, and, by way of output leads 49, controls the numeral segments in the indicator window 24 to formulate in read able form the arithmetical value of the weight of the article, in the present case 1.234 kg.

This weight value is employed in the normal manner, in conjunction with the weight and price per kilogram, to determine in a calculator of the evaluator 20 the sales price of the article, which appears in the indicator window 26.

The receiver 29 has further output leads 34 which are connected to the aforementioned display zone 28, from which the specific information from the spring balance 10 weighing the article can be read. The display zone 28 comprises three indicator windows which may contain different groups of numerals, as shown in this embodiment. Referring to the structure diagram described above, the information contained in the memory portion 51, after decoding in the receiver 29 and subsequent operation of the numerical segments in the digital portrayal system, appears in a first indicator window 31, in which the maximum permissible weight of the spring balance is shown, i.e. in the present case "10 kg". The information in the centre memory portion 52 appears similarly in an indicator window 32, showing the minimum permissible weight, i.e.

in the present case "30 g". Finally, in the same manner, a last item of information from the memory portion 53 passes to a third indicator window 33, in which the unit of calibration of the spring balance 10 is shown, which is a measure of the sensitivity of the balance. In the present case, the value "2 g is shown.

As was already mentioned initially, a great amount of information characteristic of the spring balance can be read off or called up from any evaluator 20 connected thereto which is constructed in accordance with the invention. Such additional information as, for example, the next inspection date or the production number of the spring balance 10, can appear in the display region 23, preferably by call-up, which can be effected by suitable operation of the keyboard 21. No further indicator windows are required for this purpose; this could be achieved by changing the function of windows which have formerly been used for other displays. For this purpose a manually operable switch member is sufficient. Alternatively, such a switch member might operate automatically during pauses in the operation of the spring balance to cause the desired information to appear in the various windows.

It should be understood that the control elements of the invention need not be constructed only as data memories. The information might be otherwise transmitted in the form of electrical voltages or currents to the receiver 29 of the evaluator 20 and the control elements assume the form, for example, of resistances or switch bridges, the significance of which is understood by the receivers and is expressed in the correct operation of calculations and indicator elements in the evaluator 20.

It is manifest that the data memories 30 contain fixed values incapable of manipula tion, which result in a breakdown if attempts are made at falsification, which is immediately evident visually to the consumer when the display system fails to operate.

Claims (7)

1. Weighing apparatus comprising a spring balance with weighing pan for the purpose of determining the weight of the goods, and an evaluator with indicator windows to display the weight obtained whilst specific information concerning the technical details of the spring balance connected thereto is contained in a control element and the evaluator is provided with elements which receive this information of the technical details of the spring balance, which firstly, take into account this technical information automatically, together with the weight-related measurement signals emanating from the spring balance, when determining and displaying the weight of the goods, and secondly, indicate these technical details in indicator windows.

2. Apparatus according to claim 1, wherein the control element is built into an electrical coupling half forming an extremity of the electrical connecting lead between the spring balance and the evaluator.

3. Apparatus according to claim 1 or 2, wherein in the control element there is stored maintenance information for the spring balance, which is unchanging and/or information which is variable.

4. Apparatus according to any preceding claim, including a switch determining a rest position and a working position, which switch, in the rest position, employs the indicator windows to display weights whilst, in the working position, the same indicator windows are employed to display information from said control element.

5. Apparatus according to claim 4, wherein said switch may be moved from the rest position to the working position manually.

6. Apparatus according to claim 4, wherein said switch may be caused to move automatically from the rest position to the working position during times when the spring balance is not operational.

7. Weighing apparatus substantially as hereinbefore described with reference to either of the embodiments of the accompanying drawings.