GB2515869A

GB2515869A - Method for checking a vehicle

Info

Publication number: GB2515869A
Application number: GB1406916.5A
Authority: GB
Inventors: Meredith Callahan; Jeffrey C Groshong; Eric Keerbs; Neil Clough
Original assignee: Daimler AG
Current assignee: Mercedes Benz Group AG
Priority date: 2014-04-17
Filing date: 2014-04-17
Publication date: 2015-01-07
Also published as: GB201406916D0

Abstract

The invention relates to a method for checking a vehicle (figure 1, 10), in which method an electronic control unit 22 of the vehicle is operated in a test program mode in which a plurality of lights 29, 30 of the vehicle is switched on at least temporarily by the electronic control unit , wherein in the test program mode, at least one valve 32 of a pneumatic service brake system of the vehicle is actuated by the electronic control unit thereby actuating at least one pneumatic service brake of the pneumatic service brake system and at least one switch 54 resulting in the activation of at least one stop lamp 28 of the vehicle.

Description

Method for checking a Vehicle The invention relates to a method for checking a vehicle according to the preamble of patent claim 1.

Such a method for checking a vehicle, in particular, a utility vehicle, is known from US 6 674 288 B2. In the method, an electronic control unit of the vehicle is operated in a test program mode in which a plurality of lights of the vehicle are switched on at least temporarily by the electronic control unit. In other words, in the test program mode, the activation of the lights is effected by the electronic control unit. Thereby, a pre-trip inspection of the lights can be performed by an operator of the vehicle which is configured as, for example, a commercial vehicle.

It is an object of the present invention to provide a method of the above mentioned kind.

by means of which method a particularly substantial pre-trip inspection can be performed in a very easy way.

This object is solved by a method having the features of patent claim 1. Advantageous embodiments with expedient and non-trivial developments of the invention are indicated in the other patent claims.

In order to provide a method of the kind indicated in the preamble of patent claim 1, by means of which method a particularly substantial pre-trip inspection of the vehicle can be performed in a very easy way, according to the present invention, in the test program mode, at least one valve of a pneumatic service brake system of the vehicle is actuated by the electronic control unit. The valve is configured to control a flow of air, in particular, pressurized air through the pneumatic service brake system, the air being used for actuating at least one pneumatic service brake of the pneumatic service brake system.

Thus, by actuating the valve, the pneumatic service brake is actuated. For example, the valve is designed as a solenoid valve.

Moreover, by actuating the valve, at least one switch of the vehicle is actuated which results in the activation of at least one stop lamp of the vehicle. This means the method according to the present invention is configured not only to activate the lights so that the lights can be inspected or chocked, but also to actuate the pneumatic service brake either mutually exclusive of, or sequential to, the lights so that a pre-trip inspection of the pneumatic service brake can be performed by, for example, the operator of the vehicle as well. Hence, the method according to the present invention addresses two elements of a pre-trip inspection to be performed in advance of a trip. A first one of said elements is to perform a pre-trip inspection of the lights. The second one of said elements is to perform a pre-trip inspection of the pneumatic service brake as well.

For example, the test program mode can be activated by the driver using an actuation element such as an activation switch which can be mounted on, for example, a dashboard of the vehicle. For example, the test program mode can end automatically. Alternatively.

the test program mode can be stopped by the driver by actuating the actuation element.

By means of the method according to the present invention, all exterior lights as well as the service brake system including, for example, a brake chamber push rod stroke and air leaks can be checked very easily.

The idea behind the method according to the present invention is that, currently, the service brake system of a vehicle is inspected by prying on the slack adjuster which is connected to the clevis of the brake chamber push rod to ensure that the push rod stroke does not exceed the maximum allowable limit. As an alternative to prying on the slack adjuster, for example, two people -one to apply the service brake in the driver's cab, and the other to inspect the push rod stroke -can perform the brake inspection. Many brake chambers in use today have a marking line, for example, a painted stripe to indicate the maximum safe travel of the push rod, and when the push rod stroke exceeds the maximum limit then the painted strip on the shaft of the push rod becomes visible. At the point where this marking line becomes visible, the brake shoes cannot be pressed into the brake drum with sufficient force to effect stopping of the truck, which indicates the need to either adjust or repair the service brake system.

For example, pneumatic disc brakes cannot be inspected in this manner, as the brake chamber push rod is entirely enclosed in the brake calliper mechanism. Applying the service brake is the only way to assess if the disc brake pads can make contact with the brake rotor. In addition to simplifying the process of inspecting the brake chamber push rod stroke, the method according to the present invention also enables a single person to observe any air leaks in the service brake system by simple audible recognition as they physically walk around the vehicle, and by removing the need to pry on the slack adjuster, another potential barrier to regular checks of the service brake system is eliminated. In other words, the method according to the present invention allows a single person to check the lights and the service brake system in advance of a trip. This automated lights and service brake check increases the level of the driver's awareness of brake system quality by enabling the driver to check for correct occupation of the service brake without having to use tools. Additionally, the method will reduce unexpected citations due to failure to maintain proper vehicle lighting requirements.

Further advantages, features, and details of the invention derive from the following description of a preferred embodiment as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respective indicated combination but also in any other combination or taken alone without leaving the scope of the invention.

The drawing shows in: Fig. 1 a schematic perspective view of a vehicle in the form of a truck having a plurality of exterior lights and at least one electronic control unit which is operated in a test program mode in which the lights as well as a service brake are actuated by the electronic control unit so that the lights and a service brake system of the vehicle can be checked in advance of a trip; Fig. 2 a schematic back view of the truck according to Fig. 1; Fig. 3 a schematic perspective view of a second embodiment of the vehicle; Fig. 4 a schematic back view of the vehicle according to Fig. 3; Fig. 5 a schematic perspective view of a third embodiment of the vehicle; Fig. 6 a schematic back view of the vehicle according to Fig. 5; Fig. 7 a schematic perspective view of the vehicle; Fig. 8 a schematic back view of the vehicle according to Fig. 7; and Fig. 9 a schematic view of components involved in the test program mode.

In the figures the same elements or elements having the same function are indicated with the same reference sign.

Fig. 1 shows a vehicle 10 which is a commercial vehicle in the form of a truck. Figs. 1 and 2 show a first embodiment of the vehicle 10. The vehicle 10 comprises a plurality of indication elements which are arranged in areas 12a-k. For example, in the areas 12a, lights in the form of lower beam head lamps, upper beam head lamps, parking lamps and/or front turn signal and hazard warning lamps can be arranged. In the areas 1 2b, front clearance lamps can be arranged. Front identification lamps (ID) can be arranged in the area 1 2c. Front side marker lamps and/or front side reflex reflectors can be arranged in the area 1 2d. Referring to Fig. 2, tail lamps, stop lamps, rear turn signal and hazard warning lamps, rear reflex reflectors and/or rear markings can be arranged in the areas 1 2e. At least one back up lamp can be arranged in the area 1 2f. In the areas 1 2g, rear upper body markings can be arranged.

Figs. 3 and 4 show a second embodiment of the vehicle 10. In Figs. 3 and 4, the areas 12h-k can be seen. Intermediate side marker lamps can be arranged in the area 12h.

Moreover, intermediate side marker lamps and/or intermediate side reflex reflectors can be arranged in the area 12i. In the area 12j, rear clearance lamps can be arranged. In the areas 12k, tail lamps, rear turn signal and hazard warning lamps and/or rear reflex reflectors can be arranged. Moreover, a license platel4 of the vehicle 10 can be seen in Fig. 2 and 4.

Figs. 5 and 6 show a third embodiment of the vehicle 10 which is designed as a trailer. In Figs. 5 and 6, further areas 1 6a-n can be seen in which indication elements can be arranged. For example, in the areas 1 6a, front clearance lamps can be arranged. In the area 16b, front side marker lamps can be arranged. Intermediate side marker lamps can be arranged in the area 1 6c. Rear side marker lamps and/or rear side reflex reflectors can be arranged in the area 16d. In the area 16e, side markings can be arranged.

Intermediate side marker lamps and/or intermediate side reflex reflectors can be arranged. Moreover, in the area 16g, front side marker lamps and/or front side reflex reflectors can be arranged. In the area 16h, rear clearance lamps can be arranged. Rear identification lamps can be arranged in the areas 16i. In the areas 16j, rear lower body markings can be arranged. Moreover, in the areas 16k, tail lamps, stop lamps, rear turn signal lamps and/or rear reflex reflectors can be arranged. Moreover, at least one license plate lamp can be arranged in the areas 161. In the areas 1 Sm, at least one bumper bar marking can be arranged. In the areas 1 Sn, rear upper body markings can be arranged.

Figs. 7 and 8 show a fourth embodiment of the vehicle 10 which is configured as a trailer.

In Fig. 7 and 8, further areas 16o-q can be seen. In the area iso, reflex reflectors can be arranged. In the area iSp, intermediate side reflex reflectors can be arranged. In the areas 16q, tail lamps, stop lamps, rear turn signal lamps, rear reflex reflectors and/or rear clearance lamps can be arranged. Said lamps of the vehicle 10 are lights in the form of exterior lights which should be checked in advance of a trip.

Moreover, the vehicle 10 comprises a pneumatic service brake system to decelerate the vehicle 10. The pneumatic service brake system comprises a plurality of pneumatic service brakes. For example, each service brake comprises a brake drum and brake shoes, wherein the brake shoes can be actuated by air, in particular pressurized air.

Alternatively or additionally, the pneumatic service brake can comprise at least one brake calliper and a brake disc.

Moreover, the pneumatic service brake system comprises at least one tank for storing pressurized air by means of which the respective pneumatic service brake can be actuated. Preferably, the pneumatic service brake system comprises at least one primary tank and at least one secondary tank which serve for storing pressurized air. For example, the respective pneumatic service brake comprises at least one air chamber. In order to actuate the respective pneumatic service brake, air is guided from the tank into the air chamber.

In order to decelerate the vehicle 10, the driver can actuate the pneumatic service brake system by actuating a brake pedal. In addition to inspecting the lights, the pneumatic service brake system should be checked in advance of a trip as well.

In order to realize a substantial inspection of the vehicle 10 in advance of a trip, a method for checking the vehicle 10 is provided, the method being illustrated with reference to Fig. 9. Fig. 9 shows components of the vehicle 10, the components being involved in said method for checking the vehicle 10. A first one of said components is an ignition switch 18 which can be moved in an accessory position "Acc", a run position "Run" and a crank position "Crank". The ignition switch is connected to a battery of the vehicle 10 via a pin In" and a line 20. A second one of the components involved in the method is an electronic control unit 22 (ECU) of the vehicle 10, the electronic control unit 22 comprising a microprocessor and a power distribution system which can be controlled by the microprocessor. In other words, the power distribution system is a microprocessor-controlled power distribution system by means of which electrical power can be distributed to a plurality of components of the vehicle, in particular, the exterior lights.

The power distribution system comprises power outputs 24, 26 and 27. In Fig. 9, the stop lamps of the vehicle 10 are designated with 29. The stop lamps 29 are connected to the power output 26 so that the stop lamps 29 can be supplied with electrical power via the power output 26. Moreover, lamps other than the stop lamps of the vehicle 10 are designated with 30 in Fig. 9. The lamps 30 are connected to the power outputs 24 so that the lamps 30 can be supplied with electrical power via the power outputs 24.

A further component involved in said method is an actuating element in the form of a switch 28 or switches 28 and 28a being arranged on, for example, a dash of the vehicle.

The switches 28 and 28a are connected to the electronic control unit 22 so that a Light Check (switch 28) or Brake Check (switch 28a) test program mode of the electronic control unit 22 can be actuated by actuating the switches 28 and 28a respectively, the Light Check test program mode being configured to check the exterior lights, in particular, the lamps 30 other than the stop lamps 29. The Brake Check test program mode being configured to check the stop lamps 29 and the pneumatic service brake system. For example, the switches 28 and 28a are designed as a momentary-on rocker switch.

Additionally or alternatively, a dedicated push button on a remote keyless entry key fob can be used to activate the Light Check test program mode of the electronic control unit 22.

For example, the Light Check test program mode can be activated by actuating the switch 28 once a park brake of the vehicle 10 is set and the ignition switch 18 is in the run position or the accessory position, and the vehicle speed sensor indicates 0 mph/kph.

For example, the Brake check test program mode can be activated by actuating the switch 28a once a park brake of the vehicle 10 is set and the ignition switch 18 is in the run position, the vehicle speed sensor indicates 0 mph/kph and air pressure transducers 54a and 54b indicate a minimum pressure threshold.

A further component involved in said method is a valve 32 which is designed as a solenoid valve. The valve 32 is connected to the power output 27 so that the valve 32 can be supplied with electrical power and, thus, actuated via the power output 27. The valve 32 is fluidically connected to a brake adapter valve 34 via at least one pneumatic line 36.

Moreover, the valve 32 is configured to control a flow of air from one of the tanks through the pneumatic line 36. Thus, the valve 32 is configured to control the supply of the brake adapter valve 34 with air, the brake adapter valve 34 being a component of foot valve 34a and thus a component of the pneumatic brake system, which is configured to control a flow of air from the tanks to the pneumatic service brake when the driver actuates the brake pedal designated as 38 in Fig. 9. In Fig. 9, the valve 32 is shown with the solenoid energized.

A further component involved in said method is a valve 61 which is designed as an inversion valve. The valve 61 is connected fluidically to an air outlet 60 further described below, solenoid valve 32, and brake adapter valve 34 via one pneumatic line to each respective component. The valve 61 is configured to provide a mechanical interlock to prevent the flow of air to the brake adapter valve 34 unless the park brake chambers are below a maximum air pressure which indicates that the park brakes are set.

The foot valve 34a has a secondary inlet 40 connected to the secondary tank. Moreover, the foot valve 34a has a primary inlet 42 connected to the primary tank. The foot valve 34a has a secondary outlet 44 connected to the brake chambers or relay valves of the pneumatic service brakes. The foot valve 34a further has a primary outlet 46 connected to the brake chambers or relay valves of the pneumatic service brakes. In Fig. 9, directional arrows 48 illustrate the flow of air. The brake pedal 38 and the brake adapter valve 34 are components of a so called foot valve assembly by means of which the service brakes can be actuated by the driver. In Fig. 9, the foot valve assembly is shown in a condition in which the pneumatic service brakes are released.

The pneumatic service brake system further comprises an air switch manifold 50 having an inlet 52 connected to the outlet 46 of the foot valve 34a. The air switch manifold 50 is connected to a stop lamp switch 54 by means of which the stop lamps 29 can be activated. The stop lamp switch 54 is connected to the electronic control unit 22. If the stop lamp switch 54 is closed by means of the air flowing into the air switch manifold 50 via the inlet 52, the stop lamps 29 are supplied with electrical power via the power output 26. Air flows into the air switch manifold 50 and activates or closes the stop lamp switch 54 if the pneumatic service brakes are actuated.

If the stop lamp switch 54 is open, the stop lamps 29 are not supplied with electrical power via the power output 26 so that the stop lamps 29 are switched off. The stop lamp switch 54 is open if the pneumatic service brakes are not actuated.

A further component in said method is a park brake switch 56 shown with the park brake of the vehicle 10 released. The park brake switch 56 is connected to a park brake valve via an inlet 58. The park brake valve is configured to control the park brake. In other words, the park brake is capable of being actuated via the park brake valve. Moreover, an air outlet 60 is provided, the air outlet 60 being connected to the park brake chambers. If the park brake is actuated or activated, air for actuating the park brake flows from the park brake chamber through the outlet 60 and the inlet 58. Thereby, the park brake switch 56 is closed.

Further components in said method are primary 54a and secondary 54b air pressure transducers both connected to air switch manifold 50 via inlets 52a and 52b respectively.

The transducers 54a and 54b are connected to the electronic control unit 22. The electronic control unit supplies electrical power to the transducers and receives a signal from same. The transducers 54a and 54b each provide a separate signal to the electronic control unit 22. This signal is representative of the air pressure in the respective primary and secondary air systems. Inlet 52a is connected to the primary air system and inlet 52b is connected to the secondary air system. Air switch manifold 50 maintains separate air passages for each device, where inlet 52 is for stop lamp switch 54, inlet 52a is for transducer 54a, and inlet 52b is for transducer 54b If the transducer 54a and 54b signals are not within their respective parameters the brake check feature will not be activated by electronic control unit 22 when requested by dash switch 28a.

In said method, the electronic control unit of the vehicle 10 is operated in a light check test program mode in which a plurality of the lights of the vehicle 10 are switched on at least temporarily by the electronic control unit 22. For example, in the light check test program mode, the lamps 30 are supplied with electrical power via the power outputs 24 at least temporarily.

Moreover, in the brake check test program mode, the valve 32 is actuated by the electronic control unit 22 thereby actuating the pneumatic service brakes and the stop lamp switch 54 resulting in the activation of the stop lamps 29. The brake check test program mode is activated if the driver actuates the switch 28a, if the vehicle speed is zero and if the park brake is actuated (the park brake switch 56 is closed) and the minimum system air pressure threshold (transducers 54a and 54b) is met and the ignition switch 18 is On (engine running). In other words, four different interlocks -indication of zero vehicle speed which is available from the anti-lock braking system (ABS) or the engine, an indication that the park brake is set, an indication that there is sufficient air pressure to actuate the service brakes, and the engine is running to maintain air pressure -are used to activate the brake check test program mode. The brake check test program is activated if the switch 28a is toggled to its respective "On" position and then released. When activated, the electronic control unit 22 enables a +12 volt power output to the valve 32 which is a pneumatic solenoid valve that is connected via at least one pneumatic line 36 to the brake adapter valve 34 which is, in turn, mounted onto the foot valve 34a assembly. Thereby, the vehicle's pneumatic service brakes are applied and the stop lamps 29 are illuminated via the stop lamp switch 54.

The stop lamp switch 54 which confirms the system is activated! engaged could be indicated on the vehicle display (not shown in schematic). As a diagnostic check, if the vehicle display doesn't show "engaged" when all conditions are met (key-on, feature switch on, brake set, vehicle speed zero, air pressure sufficient), then there may be a fault either with the air supply to the brake adapter valve 34 to engage the foot valve 34a which should activate the stop lamp switch 54, or the stop lamp switch circuit itself is at fault. To confirm which element is at fault, a driver can step on brake pedal 38, and if "engaged" is displayed then it is known that the stop circuit is functional and the fault lies within the application of air pressure to the brake adapter valve 34. When releasing the pedal 38 the display should read "disengaged" which confirms a mechanical fault. However if one were to toggle between stepping on the brake pedal and releasing it but the display continues to show "engaged" only when pressing on the brake pedal, then this is indicative of a mechanical failure to deliver air to the inversion valve 61, an inversion valve 61 failure to deliver air to the brake adapter valve 34, or a brake adapter valve 34 failure to engage the foot valve 34a.

Moreover, the light check test program mode is activated if the driver actuates the switch 28, if the vehicle speed is zero and if the park brake is actuated (the park brake switch 56 is closed) and the ignition switch 18 is On or ACC. In other words, three different interlocks -indication of zero vehicle speed which is available from the anti-lock braking system (ABS) or the engine, an indication that the park brake is set-are used to activate the light check test program mode. The light check test program is activated if the switch 28 is toggled to its respective bOn position and then released. When activated, the electronic control unit 22 enables a sequence of lights of the vehicle 10 that can consist of one of three implementations. A first one of said implementations consists of "always on" identification, corner, and clearance lamps on the driver's cab (for easy identification of malfunctioning lamps under all possible operating conditions) and two or more groups of lamps that alternately illuminate and extinguish. In other words, in the first implementation, at least one first group of lights is switched on and off alternatively while at least one second group of lights is constantly switched on.

A second one of the implementations consists of a sequence of lamps, starting, for example, with the left front corner of the vehicle 10 and progressing in a counter-clockwise direction around the vehicle 10, wherein each lamp turns on for a predefined amount of time until the sequence reaches the last lamp, at which time the cycle repeats.

In the third implementation, all of the lights included in the light check test program mode blink on and off at a fixed rate. The light check and brake check test program mode are deactivated when the park brake is released, the dash switches 28 or 28a respectively are toggled, or the ignition switch 18 is in the off position.

The first implementation is very easy to implement on a power distribution module wherein several lamps for a particular function (e.g. tail lamps and park lamps) are controlled by a single switching element such as a relay or transistor, and wherein these lamp functions would need to be separated into different groups to allow a complete check of exterior lamps. The amount of time that each group is on can be a fixed time or configurable from 1 to 250 seconds, in the time that the lamps are off as a control shifts from one group to another, can be set to any value from 0 to 250 seconds, with optimum times in the 5 to 10 second range.

The second implementation is suitable for a power distribution module wherein each lamp has an individual switching element, and wherein the number of installed lamps and their functions can vary widely. The second implementation lends itself to a learning mode that allows a driver or vehicle owner to teach the power distributing module subsequence to be used. The timing for the second implementation can be implemented as noted for the first implementation with additional possibilities having different time values for each lamp.

The third implementation is suitable for power distribution modules with simple microprocessor control as the software is far more complex, and wherein many different final vehicle configurations can exist (e.g. incomplete straight truck, incomplete straight truck with towered provisions, truck with fifth-wheel semi-trailer towering provisions.

tractor with fifth-wheel semi-trailer and pup trailer towering provisions). Again, as with the first implementation, timing can be a fixed value or a configurable value between 1 and 250 seconds. An example of lamp grouping for the first implementation is listed below for a controller implementing two lamp groups: A first group of lamps comprises front clearance/ID lamps, a license plate lamp, corner front left marker lamp, corner front right marker lamp, corner rear left marker lamp, corner rear right marker lamp, front left marker lamp, front right marker lamp, side left marker lamp, side right marker lamp, left tail lamp! right tail lamp, left low beam lamp, right low beam lamp, left low beam auxiliary lamp, right low beam auxiliary lamp, front left fort lamp, front right fort lamp, left daytime running lamp, right daytime running lamp, body builder connecter marker lights, body builder connecter tail lights, and of frame primary tail marker lamps, and or frame primary trailer tail lamps, trailer marker lamps and trailer tail lamps. The second group of lamps comprises front clearance/ID lamps, at least one backup lamp, left high beam auxiliary lamp, right high beam auxiliary lamp, left high beam lamp, right high beam lamp, rear left lower stop lamp, rear right lower stop lamp, left front corner turn lamp, left front side turn lamp, left rear lower turn lamp, right front corner turn lamp, right front side turner lamp, right rear lower turn lamp, body builder connecter backup lamp, body builder connecter left turn lamp, body builder connecter right turn lamp, body builder connecter stop lights, and of frame primary trailer stop lamps, left end of frame primary trailer turn lamps, right end of frame primary trailer turn lamps, trailer stop lamps, left trailer turn lamp, right trailer turn lamp, left turn signal lamp (ECU indicator), right turn signal lamp (ECU indicator) and high beam lamp (ECU indicator).

List of reference signs vehicle 12a-m area 14 license plate 1 6a-q area 18 ignition switch line 22 electronic control unit 24 power output 26 power output 27 power output 28 switch 29 stop lamp lamp 32 valve 34 break adapter valve 36 pneumatic line 38 brake pedal first inlet 42 second inlet 44 first outlet 46 second outlet 48 directional arrow air switch manifold 52 inlet 54 stop lamp switch 56 park brake switch 58 inlet outlet

Claims

Claims A method for checking a vehicle (10), in which method an electronic control unit (22) of the vehicle (10) is operated in a test program mode in which a plurality of lights (29, 30) of the vehicle (10) is switched on at least temporarily by the electronic control unit (22), characterized in that in the test program mode, at least one valve (32) of a pneumatic service brake system of the vehicle (10) is actuated by the electronic control unit (22) thereby actuating at least one pneumatic service brake of the pneumatic service brake system and at least one switch (54) resulting in the activation of at least one stop lamp (29) of the vehicle. (10).
2. The method according to claim 1.characterized in that in the test program mode, at least one first group of lights is switched on and off alternately while at least one second group of lights is constantly switched on.
3. The method according to claim 1, characterized in that in the test program mode, the lights (29, 30) are switched on and off one after another in a predeterminable sequence.
4. The method according to claim 3, characterized in that the sequence progresses in a counter-clockwise direction around the vehicle (10).
5. The method according to claim 1, characterized in that in the test program mode, the lights (29, 30) are switched on and oft in such a way that the lights (29, 30) blink at a predeterminable rate.