VEHICLE SAFETY BRAKING SYSTEM

Abstract

A vehicle safety device (200) for preventing an unoccupied vehicle moving uncontrollably. The device comprises a control module (201) and a brake module (203). The device (200) is configured to detect when a driver leaves said vehicle. The device (200) is also configured to activate, through the brake module (203), a braking system when the device detects that said driver has left the vehicle. The device may improve the safety of a vehicle in which it is fitted. A system (300) comprising the device (200) and a vehicle (400) comprising the system (300) are also described. A method of preventing an unoccupied vehicle moving is also described. The device, system, vehicle and method are particularly useful for preventing accidents in large commercial vehicles caused by a driver leaving the vehicle without engaging a parking brake.

Claims

1. A device for preventing a vehicle moving without a driver present in said vehicle, the device comprising a control module and a brake module; wherein the control module is adapted to: receive a signal from a first driver sensor in said vehicle to detect a first condition indicative of said driver leaving said vehicle; and adapted to send an activating signal to the brake module when the control module detects said first condition indicative of said driver leaving said vehicle; and wherein the brake module is adapted to engage a braking system in said vehicle when the brake module receives said activating signal.

2. The device according to claim 1, wherein said first condition indicative of said driver leaving said vehicle is the absence of said driver from a driver's seat in said vehicle.

3. The device according to claim 1, wherein said first condition indicative of said driver leaving said vehicle is opening of a door of said vehicle.

4. The device according to any proceeding claim, wherein the control module is adapted to receive a signal from a second driver sensor in said vehicle to detect a second condition indicative of said driver leaving said vehicle; and adapted to send said activating signal to the brake module when the control module detects said first and/or second conditions indicative of said driver leaving said vehicle.

5. The device according to any proceeding claim, wherein the control module is adapted to receive a signal from a brake sensor in said vehicle to detect an engaged or disengaged state of a braking system in said vehicle; and adapted to send said activating signal to the brake module when the control module detects said first condition and/or optionally said second condition indicative of said driver leaving said vehicle and detects that the braking system is disengaged.

6. The device according to claim 5, wherein the braking system which the control module is adapted to detect the engaged or disengaged state of is a parking brake system.

7. The device according to claim 5 or claim 6, wherein the braking system which the control module is adapted to detect the engaged or disengaged state of is an air brake system.

8. The device according to any proceeding claim, wherein the braking system which the brake module is adapted to engage is the same braking system which the control module is adapted to detect the engaged or disengaged state of.

9. The device according to any proceeding claim, wherein the braking system which the brake module is adapted to engage is an air brake system; and wherein the brake module is adapted to engage the air brake system by depressurising the air brake system.

10. The device according to any proceeding claim, wherein the control module is adapted to receive a signal from a gearbox sensor in said vehicle to detect a neutral or drive state of said gearbox; and wherein the control module is adapted to send said activating signal to the brake module when the control module detects that said gearbox is in neutral state.

11. The device according to any proceeding claim, wherein the control module is adapted to send a signal to an alarm module to produce an audible warning when the brake module engages the braking system in said vehicle.

12. The device according to any proceeding claim, wherein the device is adapted to communicate with an electronic control system in said vehicle to receive said signals from said first driver sensor, optionally said brake sensor, optionally said second driver sensor and optionally said gearbox sensor connected to said electronic control system.

13. The device according to claim 1, wherein the control module is adapted to: receive a signal from a brake sensor in said vehicle to detect an engaged or disengaged state of a braking system in said vehicle; receive a signal from an engine sensor to detect an on or off state of said engine; receive a signal from a gearbox sensor in said vehicle to detect a neutral or drive state of said gearbox; receive a signal from a speed sensor to detect the speed of said vehicle; send an activating signal to the brake module when the control module detects either: a) that said engine is off, that said braking system is disengaged and detects said first condition indicative of said driver leaving said vehicle; or b) that said engine is on, that said gearbox is in neutral state, that said vehicle speed is less than 10 km/h, that said braking system is disengaged and detects said first condition indicative of said driver leaving said vehicle; wherein the brake module is adapted to engage said braking system in said vehicle when the brake module receives said activating signal.

14. The device according to claim 1, wherein the device comprises a reset button or switch to restore the device to its previous condition after an emergency application of said braking system, wherein the reset button or switch deactivates the brake module so the brake module no longer engages said braking system.

15. A system for preventing a vehicle moving without a driver present in said vehicle, the system comprising: a device according to any of claims 1 to 14; at least a first driver sensor adapted to detect a first condition indicative of said driver leaving said vehicle.

16. A vehicle comprising a system according to claim 15.

17. A method of preventing a vehicle moving when a driver is absent from the vehicle, the method comprising the steps of: a) detecting the absence of the driver in the vehicle using at least a first driver sensor; and b) engaging a braking system if the at least one driver sensor determines that the driver is absent from the vehicle.

18. A device for preventing a vehicle moving without a driver present in said vehicle, said vehicle comprising an air brake system; the device comprising a control module and a brake module; said air brake system comprising a pneumatic circuit; a brake release module; and an air brake sensor system; said air brake sensor system comprising a first air brake pressure sensor, placed in said pneumatic circuit before said brake release module; and a second air brake pressure sensor, placed in said pneumatic circuit after said brake release module and before the brake module; wherein the control module is adapted to: receive a signal from said air brake sensor system to detect an engaged or disengaged state of a braking system in said vehicle; receive a signal from a gearbox sensor in said vehicle to detect a neutral or drive state of said gearbox; receive a signal from an engine sensor to detect an on or off state of said engine; send an activating signal to the brake module when the control module detects that said engine is on, that said gearbox is in neutral state, that said first air brake pressure sensor detects low pressure and that said second air brake pressure sensor detects an increase in air pressure signifying that the braking system is disengaged; wherein the brake module is adapted to engage a braking system in said vehicle when the brake module receives said activating signal.

19. A device, system, vehicle or method substantially as described herein, and/or a device, system, vehicle or method substantially as described herein with reference to the accompanying Figures and/or a device, system, vehicle or method substantially as shown in the accompanying Figures.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0187] For a better understanding of the invention, and to show how example embodiments may be carried into effect, reference will now be made to the accompanying drawing in which:

[0188] FIG. 1 shows a decision tree which illustrates the function of the device, system, vehicle and method of the present invention.

[0189] FIG. 2 is a schematic diagram of a device of the first aspect of the present invention.

[0190] FIG. 3 is a schematic diagram of a system of the second aspect of the present invention.

[0191] FIG. 4 is a perspective view of a vehicle of the third aspect of the present invention.

[0192] FIG. 5 is a flow diagram representing the method of the fourth aspect of the present invention.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

[0193] FIG. 1 shows a decision tree which illustrates the function of the device, system, vehicle and method of the present invention. This decision tree is implemented by an appropriate arrangement of electronic circuitry in a control module of the device, system or vehicle. A skilled person with knowledge of the decision tree of FIG. 1 would be able to implement this decision tree using known electronic components and arrangements. Each decision (enclosed in a diamond shape in FIG. 1) is made by a control module of the device using electronic sensor inputs and the illustrated combination of YES and NO answers produces either a decision by the device to take no action (outcome 101) or a decision to apply a parking brake in the vehicle and sound a warning message (outcome 102).

[0194] The decision process is carried out by the device or method of the present invention as follows when the device or system is fitted to a vehicle with an engine, a gear system, an air brake system arranged as a parking brake, a driver seat sensor, a door sensor and an electronic control system which uses a controller area network (also known as a CAN bus) protocol. The air brake system comprises a park brake lever for controlling the engaged or disengaged state of the air brake system, in normal operation.

[0195] First the device decides whether the engine is on (running) or not (103), for example by using a signal input from the vehicle's CAN bus. If the engine is on (running) the device decides whether the vehicle is in gear (104), for example using a signal input from the vehicle's CAN bus. If the vehicle is determined to be in gear then the device produces outcome (101) of taking no action.

[0196] If the vehicle is not in gear then the device decides whether the speed of the vehicle is less than 5 km/h (105), for example using a signal input from the vehicle's CAN bus. If the speed of the vehicle is not less than 5 km/h then the device produces outcome (101) of taking no action.

[0197] If the speed of the vehicle is less than 5 km/h then the device decides whether high pressure is present in the air brake system before the park brake lever (106), for example using a first air brake pressure sensor arranged in a pneumatic circuit of the parking brake system before the parking brake lever.

[0198] If high air pressure is not present in the air brake system before the park brake lever, the device decides whether there is low air pressure present in the air brake system after the park brake lever (107), for example using a second air brake pressure sensor arranged in a pneumatic circuit of the parking brake system after the parking brake lever.

[0199] If low air pressure is present in the air brake system after the park brake lever, the device decides whether there is a subsequent increase in air pressure in the air brake system after the park brake lever (108), for example using the same second air brake pressure sensor arranged in a pneumatic circuit of the parking brake system after the parking brake lever and before the brake module (203). If there is no increase in air pressure in the air brake system after the park brake lever then the device produces outcome (101) of taking no action.

[0200] If an increase in air pressure over 1.8 bar in the air brake system after the park brake lever is detected (effectively meaning that the parking brake is set to off) the device produces outcome (102) of applying the parking brake and sounding the warning message.

[0201] If high pressure is present in the air brake system before the park brake lever (see 106), the device decides whether high pressure is present in the air brake system after the park brake lever (109), for example using the second air brake pressure sensor arranged in a pneumatic circuit of the parking brake system after the parking brake lever.

[0202] If high pressure is not present in the air brake system after the park brake lever (therefore signifying that the parking brake is set to on), the device produces outcome (101) of taking no action.

[0203] If high pressure is present in the air brake system after the park brake lever (effectively meaning that the parking brake is set to off), the device decides whether the driver's seat is occupied (110), for example using a seat sensor fitted to the mounting of the driver's seat. The occupancy or vacancy of the driver's seat is an example of a condition indicative of a driver leaving the vehicle. If the driver's seat is occupied then the device produces outcome (101) of taking no action.

[0204] If the driver's seat is not occupied then the device decides whether the driver's door is open (111). The opening of a driver's door is an example of a condition indicative of a driver leaving the vehicle. If the driver's door is not open then the device produces outcome (101) of taking no action.

[0205] If the driver's door is open then the device produces outcome (102) of applying the parking brake and sounding the warning message. The device achieves this by activating the brake module which comprises a pressure dumping solenoid valve fitted to the pneumatic circuit of the parking brake system. Activation of the brake module causes the solenoid valve to open which depressurises the parking system and therefore causes the parking brake to be applied (102), for example by the action of a spring biasing a brake pad against a brake drum, the brake pad being previously held off the brake drum by the air pressure in the parking brake system. The device sounds the warning message through an alarm module comprising a speaker connected to the device, for example an audible message stating Please apply parking brake and press reset.

[0206] If in the first step (103) the device determines that the engine is not on (not running) then the device goes on to decide whether high pressure is present in the air brake system before the park brake lever (112), for example using a first air brake pressure sensor arranged in a pneumatic circuit of the parking brake system before the parking brake lever, missing out the decision of whether the vehicle is in gear (104). This is because when the engine is not running the vehicle may be liable to move unintentionally even if the vehicle is in gear.

[0207] If high pressure is not present in the air brake system before the park brake lever, the device produces outcome (101) of taking no action.

[0208] If high pressure is present in the air brake system before the park brake lever, the device decides whether high pressure is present in the air brake system after the park brake lever (113), for example using a second air brake pressure sensor arranged in a pneumatic circuit of the parking brake system after the parking brake lever.

[0209] If high pressure is not present in the air brake system after the park brake lever, the device produces outcome (101) of taking no action.

[0210] If high pressure is present in the air brake system after the park brake lever (effectively meaning that the parking brake is set to off), the device decides on whether the driver's seat is occupied (110) and whether the driver's door is open (111) with the same outcomes being produced as described above.

[0211] The decision tree of FIG. 1 ensures that the most common circumstances where a driver leaves a vehicle without engaging a parking brake are detected by detecting the status of the driver's seat and driver's door. The device of the present invention then applies the parking brake if the device detects that the parking brake is not engaged and either the vehicle's engine is running but the vehicle is not in gear (the gearbox is in neutral state) or that the vehicle's engine is not running. Only applying the brake in these circumstances avoids the unnecessary activation of the system, for example when the vehicle's engine is running and is in gear or when the driver opens the door but does not leave the driver's seat.

[0212] FIG. 2 shows device (200) adapted to carry out the decision tree of FIG. 1 by the arrangement of appropriate electronic circuitry. Device (200) comprises control module (201) which comprises CAN bus interface (202) for sending and receiving signals to and from a vehicle's electronic control system. Device (200) comprises brake module (203) connected to the control module (201) as shown by the hashed line. The bake module (203) comprises a pressure dumping solenoid valve, for example a ? inch BSP, 3-port, NO, 3/2, 1 exhaust, 10 bar pressure rated solenoid dump valve, for fitting to a pneumatic circuit of a parking brake system in order to perform the function described above in relation to the outcome of applying the parking brake (102).

[0213] FIG. 3 shows a system (300) adapted to carry out the decision tree of FIG. 1 by the arrangement of the appropriate electronic circuitry and sensor inputs. System (300) comprises a device (200) as shown in FIG. 2 and as described above. The device (200) comprises a CAN bus interface (202) for receiving signals from a vehicle's electronic control system regarding gearbox status, engine status, vehicle speed and door status (open or closed). The system (300) comprises a seat sensor (305), a pre-brake lever pressure sensor (306), a post-brake lever pressure sensor (307) and a brake lever sensor (308) each connected to the control module (201) as represented by the hashed lines. The CAN bus interface (202) and the sensors (305-308) provide the necessary inputs for the control module to carry out the decision tree of FIG. 1. Seat sensor (305) is an NO (normally open) type pressure switch with a diffuser. Pre-brake lever pressure sensor (306) is a Fox F4/M2 adjustable (1-12 bar), ? inch BSP, SPCO electromechanical pressure switch calibrated to 3 bar and configured to be NC (normally closed). Post-brake lever pressure sensor (307) is a Fox F4/M2 adjustable (1-12 bar), ? inch BSP, SPCO electromechanical pressure switch calibrated to 1.8 bar and configured to be NO.

[0214] FIG. 4 shows vehicle (400) fitted with device (200). The vehicle (400) is a heavy goods vehicle comprising an air brake system and an electronic control system using a CAN bus protocol. The vehicle's electronic control system provides CAN bus signals regarding engine status, gearbox status, vehicle speed and driver door opening. The vehicle is fitted with device (200) which uses CAN bus interface (202) to receive signals from the vehicle regarding engine status, gearbox status, vehicle speed and driver door opening.

[0215] Brake module (203) as described above in relation to FIG. 2 is fitted to the pneumatic circuit of the vehicle's air brake system between a park brake lever and an air control shuttle valve which provides air pressure to the park brake actuators. The bake module comprises a solenoid dump valve arranged to depressurise the pneumatic circuit when activated by the control module.

[0216] The pneumatic circuit is also fitted with a first air brake electromechanical pressure switch (pre-brake lever pressure sensor 306) placed in the pneumatic circuit before the brake release lever (i.e. in the supply line) and a second air brake electromechanical pressure switch (post-brake lever pressure sensor 307) placed in the pneumatic circuit after the brake release lever and before the brake module. The first air brake electromechanical pressure switch is calibrated to provide a positive signal if the air pressure is higher than 3 bar. The second air brake electromechanical pressure switch is calibrated to provide a positive signal if the air pressure is higher than 1.8 bar.

[0217] The device comprises a reset button/switch. The reset button/switch must be activated by manual input from a user (for example a driver) and the vehicle's parking brake must be engaged using the vehicle's standard controls, to reset the device. By reset we mean the device is restored to its previous condition after an emergency application of said braking system (a condition where the device is active and able to engage a braking system in said vehicle when the brake module receives said activating signal). Alternatively or additionally, the device may also be reset when the gearbox of the vehicle is no longer in a neutral state (i.e. the gearbox is in a drive or reverse state).

[0218] The vehicle (400) was also fitted with a seat sensor (305) which is a pressure switch fitted between the seat base and the seat's cushion squab.

[0219] In tests to simulate common roll-away circumstances, the vehicle (400) was successfully prevented from moving without the driver present by the device (200) engaging the parking brake and sounding the warning message. Also, the device (200) successfully prevented the vehicle from moving by engaging the parking brake and sounding the warning message when the engine was on, the gearbox was in neutral, the park brake lever was off and an initially low pressure in the air brake system increased to above 1.8 bar due to the power to the vehicle's compressor provided by the engine. As discussed above, any further increase in pressure would have provided a pressure sufficient to disengage the air brake system and allow the vehicle to move, risking an accident.

[0220] The example embodiments described above may reduce the risk of a vehicle moving without the driver being present and causing serious harm to persons or property, by engaging a braking system if certain conditions indicative of a driver leaving the vehicle without engaging a braking system are detected. The device, system, vehicle and method of the example embodiments identify when the engine status, gear status and parking brake system status are such that the vehicle is at risk of moving uncontrollably if a driver exits the vehicle and can therefore allow the operation of a braking system to prevent the vehicle moving. The device, system, vehicle and method of the example embodiments can detect conditions indicative of a driver leaving the vehicle, for example using a combination of sensor inputs from a driver's seat sensor and a driver's door sensor, and activate a braking system when it is highly likely that a driver has left the vehicle. Using such a combination of sensor inputs can therefore avoid accidental or unnecessary activation of the braking system.

[0221] It is expected that the rate of fatal injuries caused by a driver of a vehicle with a parking brake exiting the vehicle without engaging the parking brake will decrease significantly if the device, system, vehicle and/or method of the example embodiments are widely adopted/used, in particular by operators and/or manufacturers of large commercial vehicles.

[0222] The present invention provides a vehicle safety device (200) for preventing an unoccupied vehicle moving uncontrollably. The device comprises a control module (201) and a brake module (203). The device (200) is configured to detect when a driver leaves said vehicle. The device (200) is also configured to activate, through the brake module (203), a braking system when the device detects that said driver has left the vehicle. The device may improve the safety of a vehicle in which it is fitted. A system (300) comprising the device (200) and a vehicle (400) comprising the system (300) are also described. A method of preventing an unoccupied vehicle moving is also described. The device, system, vehicle and method are particularly useful for preventing accidents in large commercial vehicles caused by a driver leaving the vehicle without engaging a parking brake.

[0223] Although a few preferred embodiments have been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims.

[0224] Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

[0225] All of the features disclosed in this specification (including any accompanying claims, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

[0226] Each feature disclosed in this specification (including any accompanying claims, and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

[0227] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.