VEHICLE TURN INDICATOR SYSTEM

Abstract: A vehicle turn indicator system (2) including a turn indicator switch (4), left and right turn indicators (12, 14), a steering angle sensor (10), and signal processing apparatus (6, 8) responsive to the state of the switch (4) for activating the indicators (12, 14), and responsive to the steering angle sensor (10) for deactivating the indicators (12, 14).

Description: VEHICLE TURN INDICATOR SYSTEM The present invention relates to a vehicle turn indicator system. Vehicle turn indicator systems include turn indicator levers which are used to activate and deactivate left and right indicator lamps of a vehicle. The indicator levers include a sophisticated mechanical ratchet mechanism which is used to deactivate the indicators as the vehicle steering wheel is turned back towards a centre position after a turn has been completed. The mechanical ratchet mechanism also includes a latching mechanism which physically locks the lever in a turn position to ensure the left or right indicators remain on whilst a turn is completed. In accordance with the present invention there is provided a vehicle turn indicator system including: a turn indicator switch; left and right turn indicators; a steering angle sensor; and signal processing means responsive to the state of said switch for activating said indicators, and responsive to said steering angle sensor for deactivating said indicators. Preferred embodiments of the present invention are hereinafter described, by way of example only, with reference to the accompany drawing, wherein: Figure 1 is a block diagram of a vehicle turn indicator system. A turn indicator system 2, as shown in Figure 1 , includes a turn indicator lever switch 4, a steering column electronics module 6, a body electronics module 8, a steering angle sensor 10 and left and right indicator lamps 12 and 14 located around a vehicle's body. The indicator lever 4, the steering column module 6 and the steering angle sensor 10 are mounted in the vehicle's steering wheel assembly. The turn indicator lever 4 is connected to the steering column module 6 and both the steering column module 6 and the steering wheel sensor 10 are connected to body electronics module 8 by a multiplexed serial bus which forms a local area network (LAN) in the vehicle The body electronics module 8 is able to receive signals from other parts of the vehicle, such as a vehicle speed sensor 16 and a brake sensor 18, and transmit activation signals to parts of the vehicle, such as the left and right indicator lamps 12 and 14, using the LAN or dedicated wires forming part of wiring looms of the vehicle The turn indicator lever 4 is a self-centring lever with four similarly spaced switching positions LI , L2, Rl and R2 where two each are disposed on opposite sides of a centre position 20 of the lever 4 One side is tor Rl and R2 for the right indicator 14 and the other side is for LI and L2 for the left indicator 12, as shown in Figure 1 Mild actuating pressure moves the lever 4 to the first positions Rl and LI , whilst stronger pressure will move the lever to the second positions R2 and L2 A detent action at the first position Rl or LI provides tactile feedback to a driver that the first position Rl or LI has been reached The lever 4 does not include a mechanical ratchet or a latching mechanism, as is the case tor normal indicator levers, and on releasing the lever 4 it will return immediately to the centre position 20 The lever 4 includes switches which are activated for each of the positions LI , L2, Rl and R2, and the switches can be implemented using moulded silicon conductive pads Alternatively the switches may be implemented with conventional metallic contacts, vane interrupted optical switching, hall effect switches or capaciuve switching Signals representative of the state of the switches are ted to the steering column module 6 The steering column module 6 encodes the state of the switches, which represents whether the lever 4 has been placed in one of the positions LI , L2, Rl or Rl , together with the state of other switches on the steering wheel column, into serial bit stream tor transmission to the body electronics module (BEM) 8 Upon a serial bit stream request from the BEM 8. or when a switch changes state, the steering control module 6 transmits the state of all switches to the BEM 8 Alternatively the steering control module 6 may transmit only the status of the switch that has changed state, along with a switch identifier The steering angle sensor 10 converts the physical angle of the steering wheel from a predetermined position into a number that is transmitted to the BEM 8 The steering angle sensor 10 may already be provided as part of a vehicle dynamic control system which is used to effect brake control during turning as an extension of an ABS system This system is 5 included in Mercedes Benz vehicles and is described in a Society of Automotive Engineering (SAE) Technical Paper, No 950759, Advancements in ABS/TCS and Brake Technology SP-1075 Alternatively, the sensor 10 may consist of a plastic moulded annular disk magnet with a number, such as 30, of radially arranged north-south pole transitions Two magnetic sensors, such as solid state hall effect sensors, can be offset from each other by an appropriate 10 amount to generate a two-bit grey coded quadrature signal which can be ted to the steering column module 6 to determine both the direction and magnitude of rotation of the vehicle steering wheel This data can then be transmitted serially to the BEM 8 to allow the calculation of the absolute steering wheel angle As another alternative, the sensor 10 may include an optical chopper disk with alternating radially transmissive and opaque sections 15 which interrupts light of two offset optical emitter/detector pairs This again would generate a two-bit grey coded quadrature signal for the steering column module 6 to determine both the direction and magnitude of rotation of the steering wheel The body electronics module 8 controls activation and deactivation of the indicators 20 12 and 14 based on data received from the steering column module 6 and the steering angle sensor 10 The BEM 8 may also use data from other vehicle sensors 16 and 18 When the BEM 8 receives data that the lever 4 has been moved from the centre position 20 to the LI or Rl position, the BEM 8 causes the following the occur (ι) if the indicators 12 or 14 are in deactivated state, the corresponding left 25 or right indicator 12 or 14 will flash tor as long as the lever 4 is held in the LI or Rl position It the lever is held in the LI or Rl position for less than one flash period, the left or right indicator 12 or 14 will produce one full flash (n) it the opposite indicator 12 or 14 has been activated it will be deactivated For example, it the lever 4 is moved to the position LI and the 30 right indicator 14 had been activated, then the right indicator 14 is deactivated Moving the lever 4 from the positions R2 or L2 to Rl or LI , respectively, has no effect Moving the lever 4 to one of the outer positions L2 or R2 will cause the BEM 8 to hold the left or right indicator 12 or 14 in an activated state The BEM 8 determines the steering wheel angle which then needs to be traversed before the left or right indicators 12 or 14 can be subsequently deactivated The BEM 8 uses the angle data provided by the steering angle sensor 10 to determine the current angle, when the lever 4 has been moved to L2 or R2, and the deactivation angle Therefore the left or right indicator 12 or 14 will be held in an activated state until the BEM 8 receives data from the steering angle sensor 10 indicating that the deactivation angle has been reached Depending on the configuration of the steering angle sensor 10, as discussed previously, the angle information provided may be provided by the steering column module 6 Alternatively the BEM 8 may use current and historical values of vehicle speed from the speed sensor 16, brake pedal activation information from the brake sensor 18 and steering wheel angle to determine when the indicators 12 or 14 should be deactivated The vehicle turn indicator system 2 described above is particularly advantageous as it does not require use of the complex and relatively expensive mechanical ratchet and latching mechanism used in existing turn indicator levers A simpler self-centring turn indicator lever 4 can be employed allowing cost savings to be made, which are even more significant in a vehicle which already includes a steering angle sensor 10 as part of a vehicle dynamic control system Activation and deactivation of the turn indicators is determined on the basis of electronic information provided concerning steering wheel position instead of the standard mechanical and ratchet mechanism employed in existing turn indicator levers Many modifications will be apparent to those skilled in the art without departing from the scope of the present invention as hereinbefore described with reference to the accompanying drawing

Claims: CLAIMS 1 A vehicle turn indicator system (2) including a turn indicator switch (4), left and right turn indicators (12, 14), a steering angle sensor (10), and signal processing means (6,8) responsive to the state of said switch (4) tor activating said indicators (12, 14), and responsive to said steering angle sensor (10) tor deactivating said indicators (12, 14) 2 A vehicle turn indicator system as claimed in claim 1 , wherein said signal processing means (6,8) is responsive to the state of said switch (4) tor deactivating said indicators (12, 14) 3 A vehicle turn indicator system as claimed in claim 2, wherein said switch (4) is movable to one of four positions, L2, LI , Rl and R2, and a position signal representative of the position of said switch (4) is received by said signal processing means (6,8) 4 A vehicle turn indicator system as claimed in claim 3. wherein said signal processing means (6.8) activates the left or right indicators (12, 14) when the switch (4) is placed in the L2 or R2 position, respectively, and deactivates the indicators (12, 14) when the signal processing means (6,8) determines a steering wheel of the vehicle has moved a predetermined angle, on the basis of information received from the steering angle sensor (10) 5 A vehicle turn indicator system as claimed in claim 4, wherein the indicators (12,14) remain activated when the switch (4) subsequently moves to a centre position (20) between the L2 and LI positions and the R2 and Rl positions 6 A vehicle turn indicator system as claimed in claim 5, wherein the turn indicator switch (4) includes a self-centring lever which returns to said centre position (20) on release 7 A vehicle turn indicator system as claimed in any one of claims 2 to 6. wherein the signal processing means (6,8) activates the left or right indicators (12, 14) for a period of time which depends on the period of time the switch (4) is placed in the LI or Rl position, respectively 8 A vehicle turn indicator system as claimed in any one of claims 1 to 6. wherein the steering angle sensor (10) detects the angle of the steering wheel of the vehicle with reference to a predetermined position, and generates a signal representative of the angle tor the signal processing means (6,8) 9 A vehicle turn indicator system as claimed in claim 8, wherein the signal processing means (6,8) determines the angle traversed by the steering wheel after the indicator switch (4) has been placed in the L2 or R2 position, and deactivates the left or right indicators (12, 14), respectively, when a predetermined angle has been traversed AMENDED CLAIMS [received by the International Bureau on 28 May 1998 (28.05.98); original claim 6 cancelled; original claims 1-5 and 7-9 amended; new claims 10-16 added (3 pages)] 1. (Amended) A vehicle turn indicator system (2) including turn indicator switch means (4), left and right turn indicators (12,14), a steering angle sensor (10), and signal processing means (6,8) responsive to the state of said switch (4) for activating said indicators (12, 14), and responsive to said steering angle sensor (10) for deactivating said indicators (12, 14), characterised in that said indicator switch means (4) includes a self-centring lever which returns to a centre position (20) on release. 2. (Amended) A vehicle turn indicator system as claimed in claim 1 , wherein said lever is movable to one of four positions, L2, LI , Rl and R2, and a position signal representative of the position of said lever is received by said signal processing means (6,8). 3. (Amended) A vehicle turn indicator system as claimed in claim 2, wherein said signal processing means (6,8) is responsive to the state of said switch means (4) for deactivating said indicators (12, 14). 4. (Amended) A vehicle turn indicator system as claimed in claim 3, wherein said signal processing means (6,8) activates the left or right indicators (12, 14) when the lever is placed in the L2 or R2 position, respectively, and deactivates the indicators (12, 14) when the signal processing means (6,8) determines a steering wheel of the vehicle has moved a predetermined angle, on the basis of information received from the steering angle sensor (10). 5. (Amended) A vehicle turn indicator system as claimed in claim 4, wherein the indicators (12,14) remain activated when the lever subsequently moves to said centre position (20), which is between the L2 and LI positions and the R2 and Rl positions. 6. (Deleted) 7. (Amended) A vehicle turn indicator system as claimed in any one of claims 1 to 5, wherein the signal processing means (6,8) activates the left or right indicators (12, 14) for a period of time which depends on the period of time the lever is placed in the LI or Rl position, respectively. 8. (Amended) A vehicle turn indicator system as claimed in any one of claims 1 to 5, wherein the steering angle sensor (10) detects the angle of the steering wheel of the vehicle with reference to a predetermined position, and generates a signal representative of the angle for the signal processing means (6,8). 9. (Amended) A vehicle turn indicator system as claimed in claim 8, wherein the signal processing means (6,8) determines the angle traversed by the steering wheel after the lever has been placed in the L2 or R2 position, and deactivates the left or right indicators (12, 14), respectively, when a predetermined angle has been traversed. 10. (New) A vehicle turn indicator system as claimed in claim 1 , wherein the signal processing means (6,8) includes at least one data processing module which obtains state data from at least said switch means (4) and said sensor (10), and controls said indicators (12,14) based on said state data. 11. (New) A vehicle turn indicator system as claimed in claim 10, wherein said at least one data processing module includes a body electronics module (8) and a steering control module (6), wherein said steering control moudle (6) receives signals representative of the state of said switch means and encodes said signals into a data stream for said body electronics module. 12. (New) A vehicle turn indicator system as claimed in claim 11 , wherein said steering control module (6), said body electronics module (8) and said sensor (10) are connected by a communications network. 13. (New) A vehicle turn indicator system (2) including turn indicator switch means (4), left and right turn indicators (12, 14), a steering angle sensor (10), and signal processing means (6,8) responsive to the state of said switch (4) for activating said indicators (12,14), and responsive to said steering angle sensor (10) for deactivating said indicators (12,14), 5 characterised in that the signal processing means (6,8) includes at least one data processing module which obtains state data from at least said switch means (4) and said sensor (10), and controls said indicators (12, 14) based on said state data. 14. (New) A vehicle turn indicator system as claimed in claim 13, wherein said at least 10 one data processing module includes a body electronics module (8) and a steering control module (6). wherein said steering control moudle (6) receives signals representative of the state of said switch means and encodes said signals into a data stream for said body electronics module. 15 15. (New) A vehicle turn indicator system as claimed in claim 14, wherein said steering control module (6), said body electronics module (8) and said sensor (10) are connected by a communications network. 16. (New) A vehicle turn indicator system as claimed in claim 1 or 13, wherein said 20 sensor (10) is part of a dynamic control system to effect brake control for a vehicle.

Inventors: CHAMBERS MARK LEONARD DAVID, FENWICK MATTHEW DAVID, NEVGI UMESH VINAYAK, PANG PETER TAK YUEN, CHAMBERS, MARK, LEONARD, DAVID, FENWICK, MATTHEW, DAVID, NEVGI, UMESH, VINAYAK, PANG, PETER, TAK, YUEN
Applicants: BOSCH GMBH ROBERT, CHAMBERS MARK LEONARD DAVID, FENWICK MATTHEW DAVID, NEVGI UMESH VINAYAK, PANG PETER TAK YUEN, CHAMBERS, MARK, LEONARD, DAVID, FENWICK, MATTHEW, DAVID, NEVGI, UMESH, VINAYAK, PANG, PETER, TAK, YUEN, ROBERT BOSCH GMBH
Application year: 1997
Main classification: B60Q1
IPC codes: B60Q1