GB2619121A

GB2619121A - Suspension monitoring system

Info

Publication number: GB2619121A
Application number: GB2302647.9A
Authority: GB
Inventors: Green George
Original assignee: Don Bur Bodies and Trailers Ltd
Current assignee: Don Bur Bodies and Trailers Ltd
Priority date: 2022-02-23
Filing date: 2023-02-23
Publication date: 2023-11-29
Anticipated expiration: 2043-02-23
Also published as: GB202302647D0; GB2619121B; GB202202512D0

Abstract

A suspension monitoring system 100 for a heavy goods vehicle comprising a trailer and a tractive unit is described. The system comprises a suspension height indicator 110 that comprises a bracket 115 configured to couple to an axle 15 or chassis 20 of a trailer; and a member 120 coupled to the bracket, the member extends away from the bracket. The monitor comprises a sensor 150 configured to couple to a chassis of the trailer; and a processor communicatively coupled thereto. A power source supplies power. The sensor is configured to sense the position to monitor the height of the suspension relative to the axle; and the processor is configured to determine when the height exceeds a pre-determined limit and alert a user. The power source supplies power independent from power supplied from the tractive unit, allowing the suspension monitoring system to operate when the tractive unit is electrically decoupled from the trailer. The sensor may be an object sensor or light sensor. The power source may be a rechargeable battery powered by renewable energy.

Description

SUSPENSION MONITORING SYSTEM

Field

This invention relates to a suspension monitoring system, in particular for a heavy goods vehicle

Background

Heavy Goods Vehicles (HGVs) generally comprise at least one trailer coupled to a tractive unit. A common combination of trailer and tractive is that of an articulated combination. In these combinations, the height of the suspension is important to keep the trailer at the correct angle relative to the tractive unit. If the suspension is not travelling at the recommended height, it may affect braking performance, ride height, and/or damage the running gear (tyres, axles, braking and suspension components etc.).

Modern trailer heights are now increasingly getting closer to the minimum unmarked bridge height (16'6"). Modern trailer suspensions can extend in excess of 250mm, and so it has become equally critical to ensure that suspension does not extend more than required, which would risk bridge strike.

Currently, axle/braking/suspension manufacturers provide suspension height sensors. These electronic devices measure the distance that the axle extends away from the chassis typically by means of an angled "hinged" sensor. In this configuration, one arm end is attached to the chassis and the other arm end is attached to the axle. This electronic data is used by the on-board trailer computer (ECU) to determine if the trailer is running at the correct transit height (referred to as ride-height). When the suspension is not at ride-height, the ECU compares the height variance, senses the weight on the axles and sends a signal to the suspension valves to compensate accordingly.

More recently, the manufacturers of these systems have added a feature to extend the functionality of this system. When the suspension is raised above a threshold, the ECU also sends an electronic signal to a warning light (typically on the front bulkhead of the trailer) and/or siren or other suitable audio device to alert the driver to situations where the suspension is raised over the set ride-height.

Examples of such known systems are in GB2017351, GB2280877, US4466625 and US2008252025. However, the problem with all known systems is that they assume that the ECU and sensors are receiving power from the tractive unit. Based on the feedback from the sensor, the ECU acts to control the suspension. However if power is not being supplied to the ECU and sensors then no feedback is provided to the user.

As noted, typically the tractive unit is coupled to the trailer by means of several lines including an ISO 7638 ("EBS") line. This line provides both power to the trailer ECU and other systems, such as suspension actuation. The line also allows the tractive unit to communicate with the trailer via a Controller Area Network (CAN) bus data. Although it is a legal requirement to have this line connected, it has become apparent that this does not always happen. This results in a trailer that has no powered function to adjust the suspension or to address any suspension malfunction. Indeed the ECU has no knowledge of the status of the suspension. This renders the trailer "at risk".

It is an object of the present invention to at least ameliorate the above mentioned issues.

Summary of the Invention

According to a first aspect of the present invention there is provided a suspension monitoring system for a heavy goods vehicle comprising a trailer and a tractive unit. The suspension monitoring system comprises a suspension height indicator, comprising: a bracket configured to couple to an axle of a trailer; and a member coupled to the bracket, wherein the member extends away from the bracket. The suspension monitoring system further comprises a sensor configured to couple to a chassis of the trailer, and a processor communicatively coupled to the sensor. A power source supplies power to the sensor and to the processor. The sensor is configured to sense the relative position of the member to monitor the height of the suspension relative to the axle, and the processor is configured to determine when the height of the suspension exceeds a pre-determined limit and alert a user. The power source supplies power independent from power supplied from the tractive unit.

As noted, the present invention allows the suspension monitoring system to operate when the tractive unit is electrically decoupled from the trailer. This reduces a trailer having no powered function to adjust the suspension or to adjust any suspension malfunction and thus eliminates the trailer being "at risk".

Accordingly, broadly, the invention is an assembly of a sensor plate attached to an axle connected to an upstanding bracket and a sensor, such as a proximity sensor, connected to the chassis. An on-trailer power supply, such as a re-chargeable battery provides power to the sensor, and any associated processor. The power supply may be on-trailer, or may be integrated in the suspension monitoring system. Whilst able to supply power to the trailer and/or to the suspension monitoring system independently from the tractive unit, the battery may be charged from the tractive unit when coupled. Trickle charging may be used to maintain a high level of charge. A solar, or other charging source may be used instead or as well.

In embodiments, as the axle compresses/extends during transit, the sensor plate can move independently of the sensor and substantially vertically (although in reality it moves in an arced path rotating around the suspension hangar bracket). The sensor plate may be designed such that it is sensed by the proximity sensor when the suspension is either at ride height or within an acceptable tolerance of ride height. As the suspension raises further (too high), the sensor will move higher than the height of the sensor plate and will no longer be able to sense the plate. The height of the sensor plate therefore can be shortened or extended to suit the suspension type and acceptable tolerance.

When the sensor no longer senses the sensor plate, the system logic determines that the suspension is too high and sends and electronic signal/feed to an audio/visual warning device fitted in a suitable location to alert the driver.

This system, by using the supplementary battery, is not dependent on the ISO 7638 (EBS) line and can operate at all times.

Additionally, other system controls such as (but not limited to) a pressure sensor on the red emergency supply line from the tractive unit to the trailer (which acts to fill air brake chambers in the trailer) may be incorporated and powered by the on-trailer power supply. Activation of such a sensor would determine that the combination is being coupled and this could be used to arm or disarm the present system, thus preserving battery life and health.

Additionally, other alarm mechanisms to alert to driver such as (but not limited to) wired, Wi-Fi or Bluetooth TM connectivity with an in-tractor audio/visual warning device may be incorporated and powered by the tractive unit.

Additionally, other system controls may be integrated with this system to provide a brake interlock effect. This may be used to prevent the trailer being moved until the suspension is within acceptable tolerances. For example, it would not be acceptable to apply brakes in transit. Additionally, to compensate for "bump & roll" in the suspension movement, additional sensors may be added in conjunction with a logic board.

In some examples, the member may extend away perpendicular from the bracket. The height of the suspension can be measured by the relative positions of the sensor and the suspension indicator. During transit, the axle of the trailer tends to compress/extend/flex, and the suspension indicator and sensor moves relative to one another. This movement may be substantially vertical. If the suspension height increases, the height of the sensor relative to the suspension indicator will increase. This changes the relative position of the sensor, and once a pre-determined limit is reached a user can be alerted.

Advantageously, the suspension monitoring system of the present invention does not require moving parts in contact with one another. This improves the durability of the system relative to the hinged prior art system discussed previously, because there is no wear between components. The present arrangement also advantageously provides easier maintenance and replacement of the various components if necessary: the sensor can be replaced without needing to detach the indicator, for example.

Further advantageously, the suspension monitoring system comprises a processor separate to the on-board trailer computer (ECU). This allows for the height determination to be performed when power is not being supplied to the ECU (i.e. when the EBS line is not coupling the tractive unit to the trailer.

The sensor may be an object detection sensor, such as a proximity sensor. Examples of object detection sensors include electro-mechanical, pneumatic, magnetic, inductive, capacitive, photoelectric, and ultrasonic sensors. The trailer computer may determine that the height of the suspension has exceeded the pre-determined limit because the object detection sensor can no longer sense the member.

Advantageously, this means that the dimensions of the extending member helps to define the limit, and so the limit can be changed to suit different trailer heights, loads or jobs by changing the (e.g.) length of the member. The height of the end of the member may be shortened or extended to suit the suspension type and acceptable tolerance. This could be implemented by providing different sized members, or changing the nature of the coupling to the bracket. Alternatively, a uniform limit can easily be set by providing uniform members.

The suspension monitoring system may further comprise a power source configured 30 to supply power to the sensor and/or the processor. The power source may comprise two power supplies -one for the sensor and one for the processor. The power source may typically be a stand-alone unit integrated with the suspension monitoring system such that the suspension monitoring system is able to operate without drawing power from the tractive unit.

The power source may comprise a rechargeable battery. Optionally or preferably the 5 battery may be charged by at least one of: a renewable energy source such as a solar panel; and/or (H) the tractive unit by use of an electronic braking system (ISO-7638 EBS) line, the primary electric line (24N), or the secondary electric line (24S).

Advantageously, supplying a separate power source means that the suspension monitoring system is not reliant on the power supply from a tractive unit. This means it is not reliant on the EBS line (15-7638) being coupled to the trailer for each journey, which is an issue with the prior art systems discussed previously. The rechargeable battery may be trickle charged or float charged by the trailer unit or the tractive unit to maintain a fully charged battery while the suspension monitoring system is in operation. Alternatively, a renewable energy source, such as a solar panel, could be utilised.

The suspension monitoring system may comprise a plurality of sensors. The plurality 20 of sensors may be configured to communicate with the processor; and the trailer computer configured to determine whether the pre-determined limit has been exceeded based on the signals provided by the plurality of sensors.

Advantageously, using a plurality of sensors compensates for bump and roll of the suspension during transit. A plurality of sensors communicatively coupled to the trailer computer allows the computer to determine the position of the member of the suspension indicator more accurately, and reduce the likelihood of a 'false alarm' of the suspension height limit incorrectly appearing to have been exceeded.

The suspension monitoring system may be configured so that the user/driver of the vehicle is alerted by an audio and/or visual alarm communicatively coupled to the trailer computer. This communicative coupling may be wired or wireless, using e.g. VVi-Fie Direct, or BluetoothO.

The suspension monitoring system may further comprise an activation switch configured to arm/disarm the suspension monitoring system.

Advantageously, using an activation switch can ensure that the suspension monitoring system is not always on. This helps to preserve battery life in the instance where the system is powered by a battery. Additionally, it can allow a user to have the system off when suspension height is not a concern (e.g. while parked or before loading or during maintenance of the trailer). This may be particularly pertinent when unnecessary alerts could trigger an audio/visual alarm The activation switch may comprise a pressure sensor configured to couple to an emergency air coupling line, such that the system is armed when the emergency coupling line is in use.

Advantageously, this arrangement ensures that the system is only armed in scenarios when a user would be concerned with the suspension height (i.e. in transit, or before departure). Unlike other lines, such as the (ISO-7638) EBS line, the emergency coupling line is always coupled between the trailer and a tractive unit when the trailer is coupled to the tractive unit. When the emergency coupling line is decoupled, the trailer brakes are active and so the trailer can only be moved when the emergency coupling line is coupled between the trailer and the tractive unit.

The suspension monitoring system may also be in communication with a braking or locking system. The trailer computer may be configured to determine and apply a brake, such as an inter-lock, to an or each wheel of the trailer, preventing the trailer being transported until the suspension height is suitably modified. The braking system may be configured to only be possible to activate before departure. The braking system is not permitted to apply any braking force to the or each wheel of the trailer during transit.

According to a second aspect of the present invention, there is provided a trailer for a heavy goods vehicle. The trailer comprises at least one axle; a chassis configured to bear the load of the trailer associated with the axle; and the suspension monitoring system of any embodiment of the first aspect. The bracket of the suspension indicator is coupled to one of the axle or the chassis of the trailer, and the sensor is coupled to the other of the chassis or the axle. Preferably, the suspension indicator is coupled to the axle, with the sensor coupled to the chassis of the trailer. Advantageously, this arrangement simplifies the wiring configuration of the suspension monitoring system.

In an embodiment, the power supply may be integrated with the suspension monitoring system. This removes the reliance on power connection between the trailer and the tractive unit to power the monitoring system. As noted above, this can be subject to failure and/or omission, which can leave the trailer "at risk". By providing the suspension monitoring system with power from either the trailer and/or from an integrated power supply, such as a rechargeable battery, the monitoring system is active even when power is not provided by the tractive unit and thus the trailer is not placed at risk.

According to a third aspect of the invention, there is provided a kit of parts comprising the components of the suspension monitoring system of any embodiment of the first aspect of the invention.

It can be appreciated that features described in relation to one aspect may be equally applied to alternative complementary aspects.

Brief description of Drawings

Embodiments will be described, by way of example only, with reference to the drawing, in which Figure 1 is a suspension monitoring system according to an embodiment of the present invention in place within a trailer chassis; and Figure 2 is a close up view of the suspension monitoring system of Figure 1.

Detailed description of embodiments

Figures 1 and 2 show a suspension monitoring system 100 for use to detect a height of a trailer according to an embodiment of the present invention. The suspension monitoring system 100 is in place within a trailer chassis 20, typically along the axle 15 and adjacent to the suspension 30. The suspension monitoring system 100 comprises a suspension height indicator 110, and a sensor 150.

In the embodiment shown, the suspension height indicator 110 comprises a bracket 115 coupled to the axle 15 of the trailer. A member 120 is coupled to (or integral with) and extends substantially perpendicularly from the bracket 115. The member 120 in the illustrated embodiment is a plate that acts to indicate to the sensor 150 the presence (or absence) of the member. The sensor 150 is coupled to the chassis 20 of the trailer with coupling means. In the illustrated embodiment, the coupling means is a sensor bracket 155 and the coupling means is coupled substantially adjacent to the suspension air bags 30 of the trailer such that movement of the axle 15 relative to the chassis 20 changes a height of the indicator 110 and accordingly triggers the sensor if the predetermined height difference between the axle and the chassis 20 is exceeded. An exceeded height typically indicates that the height of the trailer is at dangerous or unsafe high levels. In the illustrated embodiment, the height of the sensor 150 within the coupling means 155 can be varied, allowing for adjustment of the suspension height limit.

The sensor 150 is communicatively coupled to a trailer computer (not pictured). This communicative coupling could be wireless or, as in the illustrated embodiment, could be achieved with a wired connection (not shown). The wired connection may also connect the sensor 150 to a power supply (not pictured).

As noted above, the sensor 150 is configured to sense the position of member 120. When the sensor 150 cannot sense the presence of the member 120, it signals the trailer computer (not pictured). The sensor 150 is a fixed height relative to the trailer chassis 20 and will be unable to sense the presence of the member 120 when it moves above the edge of the member 120. In this instance, the height of the chassis 20 relative to the axle 15 will have exceeded the pre-determined limit, i.e. the suspension height is over the pre-determined limit. The trailer computer is configured to determine this from the signal, and configured to alert a user of the vehicle.

In the present embodiment, the sensor 150 is a magnetic proximity sensor, with movement of the plate 120 moving in close proximity to the sensor 150 triggering a signal from the sensor. The proximity sensor may be magnetic or inductive, acting as a digital switch to send a binary signal to the trailer computer that indicates the presence (or lack thereof) of the plate, and accordingly gives an indication that a height of the plate 120 (and accordingly the axle 15 of the trailer) is at a typical or safe level, or that the trailer is higher than the predetermined trigger height (i.e. that the plate is not detected by the sensor) and thus that the trailer height is potentially unsafe.

It can be appreciated that whilst a magnetic sensor is shown, other forms of sensor could be used. An inductive sensor is one option, as is a light sensor. Contact sensors are also possible, although given the location of the sensor, a non-contact sensor is preferred.

The monitoring system is typically powered by a power source, such as a battery or the like, in particular a rechargeable battery. The power source is configured to supply power to the sensor and/or the processor. Two power supplies -one for the sensor and one for the processor may be used. The power source is a stand-alone unit that acts independent from power supplied from the tractive unit such that the suspension monitoring system is able to operate without drawing power from the tractive unit.

The power source is typically a rechargeable battery. In embodiments the battery can be recharged by a renewable energy source such as a solar panel; and/or the tractive unit by use of an electronic braking system (ISO-7638 EBS) line, the primary electric line (24N), or the secondary electric line (245).

As noted previously, supplying a separate power source means that the suspension monitoring system is not reliant on the power supply from a tractive unit. This means it is not reliant on the EBS line (IS-7638) being coupled to the trailer for each journey, which is an issue with the prior art systems discussed previously.

In order to provide a further fail-safe, the suspension monitoring system may further comprise a battery level indicator to provide a warning if the battery level is below a predetermined threshold level.

From reading the present disclosure, other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features which are already known in the art of trailer design and which may be used instead of, or in addition to, features already described herein.

Although the appended claims are directed to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel feature or any novel combination of features disclosed herein either explicitly or implicitly or any generalisation thereof, whether or not it relates to the same invention as presently claimed in any claim and whether or not it mitigates any or all of the same technical problems as does the present invention.

Features which are described in the context of separate embodiments may also be provided in combination in a single embodiment. Conversely, various features which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination. The applicant hereby gives notice that new claims may be formulated to such features and/or combinations of such features during the prosecution of the present application or of any further application derived therefrom.

For the sake of completeness it is also stated that the term "comprising" does not exclude other elements or steps, the term "a" or "an" does not exclude a plurality, and reference signs in the claims shall not be construed as limiting the scope of the claims.

Claims

CLAIMS1. A suspension monitoring system for a heavy goods vehicle comprising a trailer and a tractive unit, the suspension monitoring system comprising: a suspension height indicator, comprising: a bracket configured to couple to an axle or chassis of a trailer; and a member coupled to the bracket, wherein the member extends away from the bracket; a sensor configured to couple to a chassis of the trailer; a processor communicatively coupled to the sensor; and a power source for supplying power to the sensor and to the processor; wherein: the sensor is configured to sense the position of the member to monitor the height of the suspension relative to the axle; the processor is configured to determine when the height of the suspension exceeds a pre-determined limit and alert a user; and the power source supplies power independent from power supplied from the tractive unit.
2. The suspension monitoring system of claim 1, wherein: the sensor is an object-detection sensor; and the processor determines that the height of the suspension has exceeded the pre-determined limit when the object-detection sensor can no longer sense the member.
3. The suspension monitoring system of claim 2, wherein the object-detection sensor is a light sensor such that the sensor and the member form a light gate.
4. The suspension monitoring system of claim 1 or claim 2, or claim 3, wherein the power source is configured to couple to the trailer.
5. The suspension monitoring system of any preceding claim, wherein the power source is integrated with one of the suspension height indicator, the sensor or the processor.
6. The suspension monitoring system of any preceding claim, wherein the power source comprises a rechargeable battery.
7. The suspension monitoring system of claim 6 wherein the battery is charged by at least one of: a renewable energy source such as a solar panel; and/or (H) the tractive unit by use of an electronic braking system line.
8. The suspension monitoring system of any preceding claim, further comprising: a plurality of sensors, wherein: the plurality of sensors are configured to communicate with the processor; and the processor determines whether the pre-determined limit has been exceeded based on the signals provided by the plurality of sensors.
9. The suspension monitoring system of any preceding claim, wherein the user is alerted by an audio and/or visual alarm communicatively coupled to the processor.
10. The suspension monitoring system of any preceding claim, further comprising: an activation switch configured to arm/disarm the suspension monitoring 25 system
11. The suspension monitoring system of claim 8, wherein the activation switch comprises a pressure sensor configured to couple to an emergency air coupling line, such that the system is armed when the emergency air coupling line is in use.
12. A trailer for a heavy goods vehicle, comprising: at least one axle; a chassis configured to bear the load of the trailer associated with the axle; and the suspension monitoring system of any of claims 1 to 9, wherein the bracket is coupled to one of the axle or the chassis, and the sensor is coupled to the other of the axle or the chassis.
13. A kit of pads comprising the components of the suspension monitoring system of any of claims 1 to 12.