GB2099194A - Device for checking tachograph discs - Google Patents

Abstract

A device for checking tachograph discs comprises a base 10 adapted to receive and locate a tachograph disc 1 and a transparent member 20 which fits over the tachograph disc so that the transparent member and disc are rotatable relative to one another. The transparent member is marked with radial lines 23 arranged so that the angular separations between pairs of the lines correspond to predetermined intervals of time on the scale of hours marked on the tachograph disc. This enables the time intervals represented by traces in the tachograph disc to be easily checked, by setting one line against the beginning of a trace and noting the position of the end of the trace relative to another of the lines. The marked lines may include pairs of lines (such as A and F) indicating for example the maximum permitted period of continuous duty for the driver of the vehicle, and pairs of lines (such as B and C) indicating short intervals, such as half an hour. In the described embodiment, the transparent member 20 is a disc fitting into a circular recess 13 in the base 10 and the tachograph disc 1 fits into a smaller diameter recess 11. The transparent disc 20 has a portion cut away at 22 to allow the tachograph disc 1 to be rotated relative to the base 10 or to be held against the base whilst the transparent disc is rotated. The base 10 is marked with a scale 16 of hours. <IMAGE>

Description

SPECIFICATION Device four checking tachograph discs This invention relates to devices for checking tachograph discs.

Tachographs are employed, particularly in heavy goods vehicles and passenger service vehicles, to record the speed of and distance covered by the vehicle. The record is in the form of tracings made by a stylus or pen on a disc of paper or the like which is rotated at a speed of one revolution in 24 hours. The disc is printed with a scale of hours and various other scales to enable information, such as the speed of the vehicle at any time, to be read from the disc after it has been removed from the tachograph.

The tachograph normally produces separate traces on the disc indicating the vehicle speed and distance covered, and a third trace which indicates the respective periods during which the vehicle is moving and stationary and the rest periods taken by the driver.

The information recorded on tachograph discs can be read from the discs and analysed in various ways, for example by feeding the information into a computer. However, for most users, particularly those concerned with small fleets of vehicles, the main use ofthetachograph isto provide a check to ensure that drivers of the vehicles are not exceeding legally imposed limits concerning hours of duty. For example, in the United Kingdom the normal maximum permissible period for which a driver may remain on duty, including rest periods, is 12 > hours, though this is subject to some limited exemptions in specified circumstances in which the maximum may be increased to 14 hours.Similarly, the maximum permissible period of continuous driving is 4 hours and the maximum period of continuous duty (including driving and other work such as loading) without a rest period is 52 hours.

There is therefore a need for a simple and inexpensive device which facilitates the reading from tachgraph discs of such information.

This invention consists in a device for checking tachograph discs, comprising a base adapted to receive and locate a tachograph disc and a transparent member adapted to fit onto the base so as to overlie a tachograph disc on the base and so that the tachographic disc and transparent member are rotatable relative to one another, the transparent member carrying a series of markings which can be aligned with selected points on a trace on the tachograph disc, the angular separation between pairs of the markings corresponding to preselected intervals of time on a scale of hours on the tachograph disc.

By aligning one of the markings, which may be radial lines scribed on the disc, with the starting point of a trace on the tachograph disc, the device enables the user to see at a glance whether a particu lar operation has exceeded the permitted limits. For example, the transparent member may have mark ings spaced from an initial mark by angles corresponding to the maximum permitted period of continuous driving, the maximum permitted period of continuous duty without a rest period, and the maximum total period of duty.

The markings on the transparent member may also include markings separated by angles corresponding to short preset intervals, such as 12 hour, 1 hour or 1 < hours, to facilitate checking the length, e.g. of rest periods recorded on the tachograph disc.

Preferably, the base and transparent member are arranged so that the tachograph disc and the transparent member are independently rotatable on the base, and the base is marked with a scale of hours concentric with and corresponding to the scale on the tachograph disc, the markings on the transparent member being alignable with selected points on the scale marked on the base. Such a scale can be used to enable the total, e.g. of driving periods recorded on the tachograph disc to be measured by simple manipulation of the transparent member.

Suitably, the transparent member is a transparent disc having a portion cut away to expose part of the tachograph disc and enable the tachograph disc and transparent disc to be rotated independently of one another. In a preferred form of the invention, the base has a circular recess to receive the tachograph disc, and the transparent disc has a diameter greater than that of the tachograph disc and engages a surface of the base surrounding the recess. Preferably, the transparent disc fits into a larger diameter recess in the base, separated from the first recess by an annular ledge which the transparent disc engages.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a plan view of a device for taking readings from tachograph discs, in accordance with the invention, shown with a tachograph disc in position; Figure 2 is a section on line ll-ll of Figure 1; and Figure 3 is an exploded view of the device.

Referring to the drawings, a device for facilitating the taking of readings from tachograph discs comprises a base 10 of opaque plastics and a disc 20 of transparent plastics rotatable on the base.

The base 10 has a circular recess 11 of depth and diameter sufficient to receive a tachograph disc 1. In the centre of the recess 11 is an upstanding boss 12 which fits into the central hole 2 in the tachograph disc. The recess 11 is positioned within a larger diameter recess 13 in the base 10 and is surrounded by a flat ledge 14 extending between the circumferences of the recesses 11 and 13. The flat upper face 15 ofthe base 10 surrounding the larger recess 13 is marked with a scale 16 of hours, corresponding to the scale 3 of hours printed on the tachograph disc 1.

The rotatable disc 20 is of a diameter to fit closely inside the outer recess 13, so that it can rest on the ledge 14, and has a central aperture 21 to fit over boss 12. The disc 20 has a segment cut away along straight edge 22 to enable the user to engage a tachograph disc 1 with his fingers whilst the disc is positioned in the recess 11. The depth of the inner recess 11 is such that when the transparent disc 20 is held firmly against the ledge 14 by the user, a tacho graph disc 1 in the recess 11 can be easily rotated relative to the base 10 and transparent disc 20, the user's fingers engaging the portion of the tacho graph disc 1 not covered by the transparent disc 20.

Similarly, the tachograph disc 1 can be held in position on the base 10 by the user whilst the transparent disc 20 is rotated over it.

The transparent disc 20 is marked on its underside with a series of nine radial lines 23, which are marked with the letters A to H and J. The lines A and G at the ends of the series of lines meet the circumference ofthe disc at positions near the straight edge 22. The lines are of sufficient length to extend over the portion of the tachograph disc which carries the traces 3 and 4 indicating the speed and distance covered by the vehicle and the trace 5 indicating the periods of driving and stationary periods of the vehicle and rest periods. The lines A, F and G extend to the circumference of the transparent disc 20 so that the positions of those lines against the scale of hours 16 on the base 10 can be read off.

The lines A and G are separated by an angle of 210 , corresponding to an interval of 14 hours on the scale ofthetachograph disc. As mentioned above, this interval is the maximum permitted period for which the driver of a vehicle may remain on continuous duty. The angle between lines Ato F corresponds to an interval of 1212 hours, i.e. the normal maximum permitted period of continuous duty.The other lines are similarly positioned so that the angles between various pairs of lines correspond to particulartime intervals, as follows: A- B 4 hours (maximum period of continuous driving) A- E 52 hours (maximum period of continuous duty without a rest period) A- F 122 hours (normal maximum period of continuous duty) A-G 14 hours (maximum period of continuous duty in exempted conditions) B-C sEhour B-D 1 hour B-E 1 hours B-H 15 minutes C-J 20 minutes In operation of the device, the transparent disc 20 is lifted from the base 10, a tachograph disc 1 is placed in position in the recess 11 and the transpar ent disc replaced. The transparent disc 20 is rotated until the line A is set at "zero" on the scale 16 on the base 10, as shown in Figure 1.The user then holds the transparent disc 20 firmly against the base 10 and rotates the tachograph disc 1 until the beginning of the trace 5 is aligned with the line A. By inspecting the end of the trace 5 to see whether it lies beyond the line F or G, the user can immediately see whether the total time the driver has spent on duty exceeds the applicable maximum of 12 < or 14 hours. By inspecting whether the first rest period indicated on thetrace beginsata pointbeyondthe line E,the user can see whether the driver has exceeded the per missible period of 5 < hours continuous duty without a rest period.To check on the next period of continuous duty the tachograph disc 1 is rotated until the end of the first rest period is aligned with line A and the beginning of the next rest period is noted.

Any subsequent periods of continuous duty can be similarly checked. In the same way, each period of continuous driving can be checked to ascertain whether it exceeds the permissible limit of four hours, by rotating the tachograph disc 1 until the beginning of each portion of the trace 5 indicating driving is aligned with line Aand noting whether the end ofthat portion of the trace lies beyond the line B.

To check the lengths of each rest period recorded on the trace, the tachograph disc 1 is rotated until the beginning of the portion of trace denoting the rest period is aligned with line B, and the position of the end of the rest period trace relative to the appropriate one of lines C, D or E (denoting rest periods of 2 hours, 1 hour and 12 hours respectively) is noted.

The intermediate lines H and J enable rest periods of intermediate length to be checked.

The device can also be used to measure the total hours spent on duty, and to measure the total time spent in driving. To measure the total hours spent on duty, the transparent disc 20 is set so that line A is at zero on the scale 16 and the tachograph disc 1 set so that the start of the trace5 is aligned with line A. The tachograph disc 1 is then held firmly against the base 10, and the transparent disc 20 is rotated until the line F (or G) lies at the end of the last portion of the trace. The total hours on duty including rest periods is then indicated by the position of the line F (or G) on the scale 16. To measure the total time spent in driving, the transparent disc 20 is again set with line A at zero, and the tachograph disc set so that the beginning of the first "driving" portion of trace 5 is aligned with line A.The tachograph disc 1 is then held stationary, and the transparent disc 20 rotated until the line A is at the end of the first driving portion of the trace. The transparent disc 20 is then held stationary and the tachograph disc 1 rotated in an anticlockwise direction until the beginning ofthe second driving portion of the trace is aligned with line A, and the transparent disc 20 is then again rotated until line A is at the end ofthe second driving portion. This process is repeated until the end of the last driving portion of the trace has been reached.

Since the transparent disc 2Q has then been moved successively over the driving periods, the final posi tion of line A on the scale 16 indicates the total time spent in driving. A similar procedure can be used to measure the total of the rest periods. The total: hours on duty excluding rest periods can be calculated by substracting the total rest periods from the total hours on duty, and the total time spent in work other than driving can be calculated by substracting the total driving time and total rest time from the total hours spent on duty.

The described device thus provides a simple and inexpensive means for checking quickly and easily the information provided on tachograph discs.

It will be appreciated that modifications could be made in the described embodiment. For example, if the device is required only to check whether the var ions time limits have been exceeded, the scale 16 on the base 10 could be omitted.

Claims (10)

1. A device for checking tachograph discs, com prizing a base adapted to receive and locate a tacho graph dish and a transparent member adapted to fit onto the basesoasto overlie a tachograph disc own the base and so that the tachograph dise and transparent member are rotatable relative to one another, the transparent member carrying a series of markings which can be aligned with selected points on a trace on the tachograph disc, the angular separation between pairs of the markings corresponding to preselected intervals of time on a scale of hours on the tachograph disc.

2. A device as claimed in claim 1, in which the base and transparent member are arranged so that the tachograph disc and the transparent member are independently rotatable on the base, and the base is marked with a scale of hours concentric with and corresponding to the scale on the tachograph disc, the markings on the transparent member being alignable with selected points on the scale marked on the base.

3. A device as claimed in claim 2, in which the transparent member is a transparent disc having a portion cut away to expose part of the tachograph disc and enable the tachograph disc and transparent disc to be rotated independently of one another.

4. A device as claimed in claim 3, in which the base has a circular recess to receive the tachograph disc, and the transparent disc has a diameter greater than that of the tachograph disc and engages a surface of the base surrounding the recess.

5. A device as claimed in claim 4, in which the transparent disc fits into a larger diameter recess in the base, separated from the first recess by an annular ledge which the transparent disc engages.

6. A device as claimed in any preceding claim, in which the base has an upstanding boss of circular cross-section which fits into a circular aperture in the transparent member.

7. A device as claimed in any preceding claim, in which the markings on the transparent member comprise lines extending along radii centred on the axis of rotation ofthe transparent member.

8. A device as claimed in any preceding claim, in which the markings on the transparent member include marks spaced from an initial mark by angles corresponding respectively to predetermined maximum permitted periods of duty as recorded on the tachograph disc.

9. A device as claimed in claim 6, in which the markings on the transparent member include marks separated by angles corresponding to preset intervals shorter than the said maximum periods of duty.

10. A device for checking tachograph discs, constructed, arranged and adapted to operate substan tially as described with reference to, and as shown in, the accompanying drawings.