GB2032668A - Vehicle speed control - Google Patents

Abstract

Apparatus disposed alongside a road or railway track for detecting the presence or speed of road or rail vehicles as these break beams of radiation directed across the road or track. The apparatus includes means for transmitting warning and/or regulating signals to the vehicle for speed control. The apparatus is portable and battery operated.

Description

SPECIFICATION ROVER-Regulation Of Velocity by Emitted Radiation This invention is designed to prevent accidents on roads and railways by means of the breaking of a beam from the unit which activates transmissions of radiation from the unit to the vehicle or engine and/or ancillary units.

For road use, if the speed of the vehicle is above that set on the unit, a warning legend can be illuminated and/or automatically corrects the speed.

For rail use, the unit will monitor and automatically correct the speed. Set, say, before a station, they will also monitor and correctly deccelerate and stop the train. They can also be set to stop the train at any point along the line, and will also reduce the speed to any required for that part of the track. For use at level-crossings, the units will stop the train if the track is abstructed or the gates are set incorrectly.

This invention can be used in almost any weather conditions, including fog, at night, and in ambient temperature.

The present method is to bury a loop of wire under the surface of the road or track which works by magnetic induction, whereas my invention works by emission of beams of radiation of different frequencies.

The present methods, by also requiring the laying of power lines to power the loops, causes the equipment, when once installed, to be permanently situated in that position whereas, as my device is self-contained, the power supply being contained in the unit, no power lines are required to be laid, neither does the road or track have to be dug up, therefore my invention is completely mobile, being able to be placed anywhere along the road or track in a few minutes by anyone, requiring no special technical knowledge to do this.

With present methods, the speed setting is set manually and there is no method of controlling the speed of the vehicle, whereas my invention not only monitors but also automatically corrects the speed of the vehicle, and the speed and control settings can not only be set manually, but can also be set by emitted transmission from a passing vehicle or train.

Compared with present loop methods, capital and installation costs are very low, as are the running costs, the current drawn while a vehicle or train is passing being about 200mA as opposed to over 4A with the loop system.

DESCRIPTION OF THE INVENTION The unit is activated on the 'fail-to-safe' principle 'Fail-safe' circuitry is incorporated.

Holding circuits to be described by the abbreviation H/C.

To indicate when the battery is low and needs recharging, an indicator is fitted in the box. For low-volume traffic, and use in emergency situations, a socket (54) is fitted to the box for the rechargeable batteries contained therein. For higher-volume traffic, an accumulator is contained in the case at the base of the poles or box supporting the unit.

Transmitters Ct (26), Dt (10) and Nt (58), and receivers Cr (41), Dr (29) and Nr (55) can be in duplicate in case one fails, in which case the other takes over, and the fail-safe circuit (19) is activated.

The speed setting (for monitoring the speed) and control setting (of the speed to which the speed of the vehicle or train is to be increased or reduced) can be set manually, or if required, say, in emergency conditions (such as patchy fog) where speed is essential, can be set by transmission of a modulated carrier wave from a passing vehicle or engine.

If set manually, the speed setting can be set by a rotary switch (52) (Fig. 7B) in the side of the box, or by a microswitch (56) (Fig. 7B). Similarly, the control setting can be set by a rotary switch (53) (Fig. 7B) in the side of the box, or by a microswitch (56) (Fig. 8).

The setting of both the speed and control can be marked directly in m.p.h., or km. hr., the calibration being marked in lines (for the rotary switch), or an electronic array or display (for the microswitch).

If set from a passing vehicle or engine, as shown in Fig. 8, the modulated carrier wave from Nt (58) is received by receiver Nr (55) on the front of the unit, and passed to the logic circuit (57) which provides the correct capacitor and resistor values to cause the relevant oscillators to give out the correct frequency, as each setting requires a different frequency.

To set the transmitter, as shown in Fig. 9, the microswitch is pressed until the setting indicator (62) (an electronic array or display) shows the speed required. As the vehicle or engine passes the unit, the transmitter is pointed at the unit and microswitch (60) held down for a short time while the output from the logic circuit (61) transmits the modulated carrier wave from Nt (58) to the receiver Nr (55) on the unit.

INPUT TO UNlT(Fig. 7) When the beam from E is broken by a passing vehicle or engine, the output from A (which is normally amplified by M) drops to a logic '0', activating H/C1 (2) (Figs. 1 and 2). The output from H/C1 (2) passes via (21) to the reset of H/C3 (6), enabling H/C1 (2) to activate the main logic circuit (5).

Output E' similarly causes B (3) to activate its relevant part of the main logic circuit (5) via H/C2 (4).

FAIL-SAFE (Fig. 7C) The output from transmitter E is reflected from the plate (51) back to receiver A and hence via amplifier M to H/C1 (2). If transmitter E fails, receiver K (15) gives out a logic '0' whidh is inverted by G (16) to a logic '1' which activates the fail-safe circuit (19). Similarly for transmitter INPUTS AND OUTPUTS

Receiver A (1) Receiver B (3) Receiver K (15) All are on the same frequency. Almost any frequency can Receiver K' (17) be used including radio and infra-red.

Transmitter E Transmitter E' Transmitter Dt (10) and receiver Dr (29) are on a given frequency which is different from those above.

Transmitter Ct (26) and receiver Cr (41) are on a given frequency which is different from any of those above.

Transmitter Nt (58) and receiver Nr (55) are on a given frequency which is different from any of those above.

Transmitters E and E' should have a narrow beam.

Transmitters Dt (10), Cr (26) and Nt (58) should have a wide-angle beam.

Warning Legend (14) is an illuminated sign.

E is vertically above A (1 ) and E' is vertically above B (3).

The distance from A to B is 12 inches in the Imperial system.

The distance from A to B is 30 centimetres in the Metric system.

TO ALIGN THE EQUIPMENT(Fig. 6) The plank or pole Z is placed on the rails and held temporarily in position by a clamp (48).

Plank or pole K is raised to a vertical position and held so by a catch (50). Plamk or pole L is also raised to a vertical position and held so by a catch (50). The unit is then adjusted for height on its poles until the base of the unit is level with the top of the pole K. The reflector plate (51) is similarly adjusted for height on its poles until the base of the plate (51) is level with the top of the pole L. Transmitters Dt (10) and Ct (26) are thus brought into line with the receivers Dr (29) and Cr (41) on the engine. The frame is them folded up and removed from the track.

UNIT FOR ROAD USE(Fig. 1) CORRECT SPEED An output is given from L which passes to H/C3 (6) to reset the circuit via (22).

ABOVE CORRECT SPEED An output is given from M which passes through H/C4 (7) to the relay (11) which activates the heavy-duty relay (12), the contacts of which pass to an inverter circuit (13) to raise the voltage to that necessary to illuminate the warning legend (14). The output of H/C4 (7) also passes to the timer (8) which, after a set time, resets H/C4 (7).

Output M also passes to the control logic circuit (9) and hence to Dt (10) which, by pulse modulation of the carrier wave from Dt, reduces the speed to that which is set on the unit by (53) (Fig. 7B). The output from the control logic circuit (9) also passes to the timer (8) which, after a set time, resets the control logic circuit (9).

Output M also passes to H/C3 (6) to reset the circuit via (22).

UNIT FOR RAIL USE (Fig. 2) BELOW CORRECT SPEED Below a specified point below the correct speed, an output is given from L to the control logic circuit (9) which, by pulse modulation of the carrier wave from Dt (10), increases the speed of the train to that set on the unit. The output from L also passes to the timer (25) and hence to H/C3 (6) which resets the circuit via (22).

CORRECT SPEED An output is given from M which passes via the timer (25) to H/C3 (6) to reset the circuit via (22).

TOP PERMITTED SPEED An output from P passes to transmitter Ct (26), the output of which activates a warning signal (42) (Fig. 4) (audio and/or visual) in the cab. Output P also passes via the timer (25) to H/C3 (6) to reset the circuit via (22).

ABOVE THE CORRECT SPEED An output is given from Q which passes to the control logic circuit (9), and hence to Dt (10) which, by pulse modulation of the carrier wave from Dt (10) reduces the speed to that which is set on the unit, or stops the train.

There is also a by-pass switch (27), which passes via H/C5 (28) to Dt (10), causing it to give out a continuous signal to stop the train if required, say, in an emergency condition on the line.

FAIL-SAFE(Figs. 1 and 2) If any component in the unit breaks down, an output is passed to the fail-safe logic circuit (19).

The output from the fail-safe logic circuit (19) passes to the warning signals (20) on the unit (audio and/or visual). Two are used in case one fails.

CIRCUIT ON VEHICLE OR ENGINE (Figs. 3 and 4) The receivers Dr (29) pass the pulse modulated signal to the main logic circuit (30), the output of which pass to the output circuit (31).

The receivers Cr (41) pass the pulse modulated output to the warning signal (42). The output also passes to the timer (35) which, after a set time, resets the circuit via (40).

The voltage required is passed via V + (32) to the output circuit (31), the output voltage to the solenoid valve (33) or other device being changed to the voltage required to close the valve by the amount required by the number of pulses received via the main logic circuit (30). This increases or decreases the speed to that required, which is set on the unit. This output also passes via a voltage reduction circuit (34), to the timer (35) which, after a set time, passes an output to the main logic circuit (30) via (40) to reset the circuit. A cut-off switch (39) can be fitted in the cab which can, in case of necessity, cut off the effect of the receiver. To prevent abuse, each such switching can be recorded on a counter with a display, or other device.

FAlL-SAFE(Figs. 3 and 4) If one of the components in the circuitry fails, an output passes via H/C6 (36) to a fail-safe warning signal (38) (audio and/or visual) in the cab. This signal is switched off by switch (37).

LEVEL-CROSSING (Fig. 5) The units are set up at a distance S (the stopping distance of a train) from the level-crossing.

A transmitter (45) gives out a beam B which is reflected via reflectors (45), (46), and (47) back to receiver (44), the output of which passes to the units and via an invert to H/C5 (28) (Fig. 2) hence to transmitter Dt (10).

If the beam B is broken, the output from (44) is inverted to a logic '1' which, via H/C5 (28) (Fig. 2), cuses Dt (10) to give out a continuous signal which stops the train.

The reflectors should be attached to the gates so that the train is stopped, not only if the track is obstructed, but also if the gaps are open falsely showing the road to be clear.

ELECTRICAL SYSTEMS (Fig. 2) An output can also be taken from the control logic circuit (9) to H/C4 (7) and also from H/C5 (28) to H/C4 (7). The output passes to the relay (11) which activates a heavy-duty relay (12), the contacts of which can switch off the rail ahead of the train.

The output from H/C4 (7) also passes to the timer (8) which, after a set time, resets H/C4 (7) via (23).

Claims (1)

1. What I claim is that my invention is designed to prevent accidents on roads and railways (by any means of propulsion) by monitoring the speed, and also increasing or decreasing the speed to a pre-determined speed, the equipment for railways being an expansion of that used for the roads. These units can be set anywhere along the road or track. Set, say, before a station, they will monitor and also deccelerate correctly, and can also stop the train. It can also stop the train, if required, anywhere along the track. They will also stop the train if the tracks at a levelcrossing are obstructed or the gates are set incorrectly.

   The unit will also indicate, by a warning legend, that a vehicle is speeding above the set limit.

   It will also, if required, automatically reduce the speed af the vehicle to a pre-determined correct speed.

   The speed and control settings can be set manually, or can be set by a transmission of a modulated carrier wave from a passing vehicle or engine.

   Being mobile, there is no need to d.ig up the road or track, as it can be installed anywhere in a few minutes.

   There is no need for power lines to be laid (except, if required, when situated in a permanent position at, say, a level-crossing), as the unit is self-contained, the power supply being contained within the unit, and the current used is about 200mA while a vehicle or train is passing as opposed to over 4A for the pressent loop methods.

   Compared with present loop methods, capital and installation costs are very low, as are the running costs.

   This invention can be used in almost any weather conditions, including fog, at night, and in any ambient temperature.