GB2075228A - Disc reader - Google Patents

Abstract

A disc reader, for use in reading tachograph discs from a vehicle tachograph, has a rotatable table (12) and a rotatable dial (14) connected thereto by gearing (15,16, 17) which causes turning movement of the table to be magnified on the dial (14). The table (12) can support a disc (22) and the dial (14) has graduations (14), a cursor (20) overlying the table (12) and the dial (14).

Description

SPECIFICATION Disc reader This invention relates to a disc reader, that is a device for use in reading discs from a tachograph and extracting from them the information applied by the tachograph.

The discs used in tachographs are about 12 cm. in diameter and contain quite a large amount of information in the form of annular traces which have to be compared with scales on the discs to determine such factors as driving time, rest time and distance travelled. Reading such discs can be quite difficult and apparatus heretofore proposed for use in reading the discs has been complicated and expensive. An object of the invention, therefore, is to provide a simple and cheap disc reader.

Accordingly the invention provides a disc reader comprising : a table rotatable about an axis perpen dicularto its plane; means for locating a tachograph disc on the table; a dial mounted adjacent the table and rotatable about a further axis; means connecting the table and the dial for rotation in unison, the arrangement being that for each revolution of the table the dial makes more than one revolution; a scale on the dial chosen to correlate with the means connecting the table and dial; and cursor means for the dial and the table.

The means connecting the table and dial is preferably a gear means and the ratio is such that when the table turns through a given angle, the dial turns through a significantly greater angle, thus giving an effective 'magnification' of the scale of a disc on the table. A factor of two is convenient.

The cursor means can be a line on a transparent plate above the dial and table.

The means for locating the disc on the table for sliding rotary motion preferably comprises a peripheral upstanding rim.

The means for locating the disc on the table can additionally or alternatively comprise a central circular boss on the table which can engage a central aperture in the disc.

The gear means can comprise toothed wheels connected to the table and the dial and a toothed belt entrained therewith.

The invention will be described further, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a transverse section through a preferred device of the invention; and Figure 2 is a plan view of the device of Figure 1.

A preferred embodiment of device 10 of the invention comprises a horizontal base 11. Mounted parallel to the base 11 for rotation about a vertical axis is a table 12 having a central boss 13 and a peripheral upstanding rim 13a. Adjacent the table 12 and projecting beneath it is a disc-like dial 14 mounted for rotation about a parallel axis. The table 12 and dial 14 are firmly connected to respective toothed wheels 15, 16 connected by a toothed belt 17. Wheel 15 has double the number of teeth on wheel 16. A plate 18 of transparent material is supported by four pillars 19 to lie above the table 12 and dial 14 and carries a cursor line 20. The dial 14 has markings 21 at its periphery dividing it into twelve segments each representing one hour and each sub-divided into sixty minutes.

In use, a tachograph disc 22 is placed on the table 12 with its central aperture 23 engaging over boss 13. The disc 22 is now co-axial with the table 12 and can slidably move on the table, pivoting about boss 13. The table is moved, manually, to bring a zero mark on dial 14 into register with the cursor line 20.

The disc 22 is then slid -relative to the table 12, without moving the table, until the beginning of a desired trace, such as angular position (a) is aligned with the cursor line 20. The disc 22 and table 12 are now turned in unison until the end of the trace (position (b) ) is reached. Dial 14 has now been turned through an angle double the angle between positions (a) and (b)-and the time (t1) represented by the length of the trace can be read off from the dial quite easily and accurately. The process can be repeated to give the lengths of time periods (t2) and (t3). These can represent, for example, two periods of driving (t1 and t3), separated by a rest period (t2).

All these time periods can be recorded appropriately.

The device of the invention is simple to use and cheap to manufacture. It requires no power supply and is readily portable. Reading of the discs 22 is much facilitated.

The invention is not limited to the precise details of the foregoing and variations can be made thereto.

For example, a magnifying glass can be provided in the region where the cursor line overlies the table to facilitate reading of the discs. The means connecting the table 12 and dial 14 can be any convenient gear means giving the desired multiplication. The degree of multiplication is preferably two, because this makes dial 14 cover twelve hours, which is normally quite adequate for a single revolution thereof to easily cover the average working day of eight hours.

However, any other convenient factor can be used.

For example, a factor of three would cause dial 14to rotate once for each eight hours.

The cursor line need not be on a transparent sheet and could simply be a wire or the like supported above the dial and table.

Many other variations are possible within the following claims.

1. A disc reader comprising : a table rotatable about an axis perpendicular to its plane; means for locating a tachograph disc on the table; a dial mounted adjacent the table and rotatable about a further axis; means connecting the table and dial for rotation such that for each revolution of the table the dial makes more than one revolution; a scale on the dial chosen to correlate with the means connecting the dial and table; and cursor means for the dial and the table.

2. Adisc reader as claimed in Claim 1,wherein the dial and table rotate about parallel axes.

3. A disc reader as claimed in Claim 2 wherein the dial and table lie in closely adjacent planes.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Disc reader This invention relates to a disc reader, that is a device for use in reading discs from a tachograph and extracting from them the information applied by the tachograph. The discs used in tachographs are about 12 cm. in diameter and contain quite a large amount of information in the form of annular traces which have to be compared with scales on the discs to determine such factors as driving time, rest time and distance travelled. Reading such discs can be quite difficult and apparatus heretofore proposed for use in reading the discs has been complicated and expensive. An object of the invention, therefore, is to provide a simple and cheap disc reader. Accordingly the invention provides a disc reader comprising : a table rotatable about an axis perpen dicularto its plane; means for locating a tachograph disc on the table; a dial mounted adjacent the table and rotatable about a further axis; means connecting the table and the dial for rotation in unison, the arrangement being that for each revolution of the table the dial makes more than one revolution; a scale on the dial chosen to correlate with the means connecting the table and dial; and cursor means for the dial and the table. The means connecting the table and dial is preferably a gear means and the ratio is such that when the table turns through a given angle, the dial turns through a significantly greater angle, thus giving an effective 'magnification' of the scale of a disc on the table. A factor of two is convenient. The cursor means can be a line on a transparent plate above the dial and table. The means for locating the disc on the table for sliding rotary motion preferably comprises a peripheral upstanding rim. The means for locating the disc on the table can additionally or alternatively comprise a central circular boss on the table which can engage a central aperture in the disc. The gear means can comprise toothed wheels connected to the table and the dial and a toothed belt entrained therewith. The invention will be described further, by way of example, with reference to the accompanying drawings, wherein: Figure 1 is a transverse section through a preferred device of the invention; and Figure 2 is a plan view of the device of Figure 1. A preferred embodiment of device 10 of the invention comprises a horizontal base 11. Mounted parallel to the base 11 for rotation about a vertical axis is a table 12 having a central boss 13 and a peripheral upstanding rim 13a. Adjacent the table 12 and projecting beneath it is a disc-like dial 14 mounted for rotation about a parallel axis. The table 12 and dial 14 are firmly connected to respective toothed wheels 15, 16 connected by a toothed belt 17. Wheel 15 has double the number of teeth on wheel 16. A plate 18 of transparent material is supported by four pillars 19 to lie above the table 12 and dial 14 and carries a cursor line 20. The dial 14 has markings 21 at its periphery dividing it into twelve segments each representing one hour and each sub-divided into sixty minutes. In use, a tachograph disc 22 is placed on the table 12 with its central aperture 23 engaging over boss 13. The disc 22 is now co-axial with the table 12 and can slidably move on the table, pivoting about boss 13. The table is moved, manually, to bring a zero mark on dial 14 into register with the cursor line 20. The disc 22 is then slid -relative to the table 12, without moving the table, until the beginning of a desired trace, such as angular position (a) is aligned with the cursor line 20. The disc 22 and table 12 are now turned in unison until the end of the trace (position (b) ) is reached. Dial 14 has now been turned through an angle double the angle between positions (a) and (b)-and the time (t1) represented by the length of the trace can be read off from the dial quite easily and accurately. The process can be repeated to give the lengths of time periods (t2) and (t3). These can represent, for example, two periods of driving (t1 and t3), separated by a rest period (t2). All these time periods can be recorded appropriately. The device of the invention is simple to use and cheap to manufacture. It requires no power supply and is readily portable. Reading of the discs 22 is much facilitated. The invention is not limited to the precise details of the foregoing and variations can be made thereto. For example, a magnifying glass can be provided in the region where the cursor line overlies the table to facilitate reading of the discs. The means connecting the table 12 and dial 14 can be any convenient gear means giving the desired multiplication. The degree of multiplication is preferably two, because this makes dial 14 cover twelve hours, which is normally quite adequate for a single revolution thereof to easily cover the average working day of eight hours. However, any other convenient factor can be used. For example, a factor of three would cause dial 14to rotate once for each eight hours. The cursor line need not be on a transparent sheet and could simply be a wire or the like supported above the dial and table. Many other variations are possible within the following claims. CLAIMS

1. A disc reader comprising : a table rotatable about an axis perpendicular to its plane; means for locating a tachograph disc on the table; a dial mounted adjacent the table and rotatable about a further axis; means connecting the table and dial for rotation such that for each revolution of the table the dial makes more than one revolution; a scale on the dial chosen to correlate with the means connecting the dial and table; and cursor means for the dial and the table.

2. Adisc reader as claimed in Claim 1,wherein the dial and table rotate about parallel axes.

3. A disc reader as claimed in Claim 2 wherein the dial and table lie in closely adjacent planes.

4. A disc reader as claimed in Claims 2 or 3, wherein the means connecting the dial and table is gear means.

5. A disc reader as claimed in Claim 4, wherein the table and dial each carry a wheel and a belt is entrained therearound.

6. A disc reader as claimed in any preceding claim, wherein the means for mounting a tachograph disc on the table is a central circular boss on the table.

7. A disc reader as claimed in any preceding claim, wherein the cursor means is a cursor line on a transparent plate above the table and dial.

8. A disc reader substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.