GB2173021A

GB2173021A - Calendar apparatus and method

Info

Publication number: GB2173021A
Application number: GB08508099A
Authority: GB
Inventors: Professor Ahmad Ali
Original assignee: ALVI SALIMUL HASSAN
Current assignee: ALVI SALIMUL HASSAN
Priority date: 1985-03-28
Filing date: 1985-03-28
Publication date: 1986-10-01
Also published as: EP0196869A1; GB2173021B; ATE54214T1; DE3672314D1; EP0196869B1; GB8508099D0; JPS61251891A

Abstract

Calendar apparatus 10 comprises two scale members, namely a fixed main body 12 and a rotatable disc 20. Scales 28 to 42 are printed on the scale members to identify data relating to centuries, years, months, day names and day numbers. The method of the invention permits the calculation of the day names for a chosen month in the past or in the future to be performed by two movements of scale 20.

Description

1 GB2173021A 1

SPECIFICATION

Calendar apparatus and method This invention relates to calendar apparatus and a method of calculating dates. By the term -calculating dates- as used in this speci fication it is intended to refer to the identifica tion of the day of the week (Sunday Monday Tuesday etc.) corresponding to a given date in a chosen month and year.

For the purpose of calculating dates, as re ferred to above, to the best of the Applicant's knowledge there only exists such apparatus as programmed calculators, and complex written or printed charts. Either of these methods and apparatus are satisfactory in their way but they are not particularly simple or convenient to use and an object of the present invention is to provide apparatus and a method of cal culating dates offering improvements either generally, or with reference to the need for simplified and/or less costly and/or more con venient and interesting apparatus to use.

According to the invention there is provided 90 calendar apparatus and a method of calculat ing dates as defined in the accompanying claims.

The invention also provides calendar appara tus and a method of calculating dates com- 95 prising any novel feature or novel combination of features disclosed herein.

An embodiment of the invention will now be described by way of example with refer ence to the accompanying drawings in which:

Figure 1 and 2 show plan views of calendar apparatus in two successive stages of the cal culation of a date; and Figure 3 shows a plan view of a movable scale of the apparatus of Figs. 1 and 2.

As shown in the drawings, calendar appara tus 10 comprises a main body 12 having ar cuate cut-outs 14 and 16 and a further slot 18 for a purpose to be described.

A disc 20 shown in Fig. 3 is mounted below main body 12 so as to be visible and actuatable through cut-outs 14, 16 and 18. Disc 20 has apertures 22 for actuation purposes and is mounted for rotation about an axis 24 by means of a pivot pin or the like (not shown) extending through main body 12.

Main body 12 and disc 20 together define relatively movable scales comprising a first set of scales 26. Set of scales 26 comprises a primary pair of scales 28 consisting of a movable scale 30 provided on disc 20 and a fixed scale 32 printed on main body 12.

Adjacent scale 32 on main body 12 is printed a block 34 of numbers or data for a purpose to be described.

A secondary pair of scales 36, 38 are pro vided on disc 20 and main body 12 respec tively for a purpose to be described.

Finally, a second set of scales are provided on disc 20 and main body 12 at the right 130 hand end thereof and comprising a days scale 40 identifying days of the week and a days of the month scale 42 associated therewith.

The apparatus is employed as follows. Figs.

1 and 2 show the use of the apparatus in calculating the day of the week corresponding to a well known date in the past. Sunday June 25th. 1916 was the Sunday preceding the start of the Battle of the Somme on the following Saturday July 1st. 1916. The calculation of the day of the week corresp nding to 25th.June 1916 is shown in Figs. 1 and 2. The first step in the process comprises employing the scale 30 (printed on disc 20) This scale relates to the century concerned. For the year 1916, one takes the first two digits ---19---and divides them by the number 4, leaving the remainder 3. The number 3 on scale 30 is then used for setting a first posi- tion of disc 20.

This first position is obtained by setting numeral 3 in scale 30 against scale 32.

The position on scale 32 against which numeral 3 should be set is determined by the duodecade concerned. As can be seen, scale 32 consists of the numerals 0, 20, 40, 60 and 80. These numerals divide a century into duodecades. For the calculation process, the relevant numeral in scale 30 is set against the numeral in scale 32 corresponding to the start of the duodecade concerned. Thus, as can be seen in Fig. 2, the figure 3 in scale 30 has been set against the figure 0 in scale 32. This identifies the first position of the relatively movable scales provided by disc 20 and main body 12.

Then, the remainder (of 16) obtained by subtracting the duodecade start number (1900, against which the figure 3 has been set) from the full number of the year concerned (1916) is obtained, and in this case is 16. The position of the numeral 16 in year scale 34 is used to identify a letter opposite it in scale 36. As can be seen from Fig. 2 the letter concerned is ---E-.

Then, disc 20 is rotated (by means of apertures 22 using slot 18 and a pointed instrument such as a pencil), until letter capital E is opposite the relevant month (June in this case). This position is shown in Fig. 1. This now defines the final position of the relatively movable scales and the days of the week corresponding to the relevant days of the month can be seen on scales 40 and 42, and it can be seen that the 25th.June 1916 was indeed a Sunday.

Among modifications which could be made in the above embodiment are changes to the exact physical form of the relatively movable scales and the manner in which they are printed or represented. It might be possible to provide linearly moving scales corresponding to a slide rule with a suitable cursor. Obviously, it is not necessary to have letters in scale 36. Any suitable identifying matter can 2 be employed. Also, if it is not desired to cover more than one century, there is no need to include the step of employing scale 30 for the purpose explained above. The initial posi- tion of disc 20 against scale 32 could be identified merely by means of printed matter showing the limited number of years actually intended to be covered by the apparatus. Obviously also, in month scale 38, the actual positions of the months could be changed in the lateral direction. Note that in this scale there are two positions each for the months January and February. Those positions in which those months are shown with heavy borders are the positions to be adopted 80 where a leap year is involved (the number of the year being divisible by 4).

Claims

1. Calendar apparatus comprising scales which are movable relative to each other, the scales including first and second sets of rela tively movable scales permitting information relating to a chosen month or date in any one of a series of years to be used to set the relative positions of the first set of scales'.

whereby the second set of relatively movable scales, identifying days of the week, are set against the days of the month to define which days in the month are Mondays, which are Tuesdays and so on.

2. Apparatus according to claim 1 wherein said first set of scales comprises primary and secondary pairs of scales, the primary pair of scales relating to the chosen year and adapted to be used to enable a first position of the first set of scales to be set, from which can be identified data enabling the secondary pair of scales to be set with reference to the rele- vant month in the chosen year, the setting of said second position serving to set said second set of scales to identify said days of the week with reference to the days of the month.

3. Apparatus according to claim 2 wherein said primary pair of scales includes a duode cade scale identifying duodecades (periods of years) within a century.

4. Apparatus according to claim 3 wherein said primary pair of scales includes a year scale identifying years 1 to 20 of each duodecade.

5. Apparatus according to any one of claims 2 to 4 wherein said primary pair of scales includes a century marker identifying the century of the chosen date.

6. Apparatus according to claim 5 wherein said primary pair of scales identifies the century by means of the number remaining when the first two digits of the century are divided by 4.

7. Apparatus according to claim 6 wherein the arrangement is such that said century marker is set against the duodecade scale identifying the duodecade so as to produce GB2173021A 2 said first position of said relatively movable scale.

8. Apparatus according to claim 7 wherein the arrangement is such that the year on the year scale identifies a second marker.

9. Apparatus according to claim 8 wherein said first set of scales includes a month scale identifying individual months of a year and against which said second marker can be set 75 so as to set the second position of said relatively movable scales.

10. A method of calculating a date (as defined herein) comprising the step of employing apparatus according to any one of the preceding claims for the purpose.

11. Calendar apparatus according to claim 1 substantially as described herein.

12. Calendar apparatus constructed and arranged substantially as described herein and as shown in the accompanying drawings.

13. A method of calculating a date (as defined herein) comprising employing apparatus according to either of claims 11 and 12.

Printed in the United Kingdom for Her Majesty's Stationery Office, Dd 8818935. 1986, 4235. Published at The Patent Office, 25 Southampton Buildings, London, WC2A l AY, from which copies may be obtained.