This specification relates to improvements in and relating to light mass transit vehicles. In particular, this specification relates to a bogie for a light mass transit vehicle. Further, it is a non-exclusive object of this specification to provide a bogie which may be more space and energy efficient, stable and/or durable along with allow self-driven movement, geo-positioning and LIDAR for absolute and relative positioning as well as collision avoidance.
Light mass transit vehicles (including light rail and road vehicles and very light rail and road vehicles) are typically designed to be reduced-weight versions of mainline (heavy) mass transit vehicles and travel with a lower payload and at lower speeds.
A bogie (sometimes known as a truck) typically provides a tractive force to move a vehicle body. Generally, a bogie includes at least a chassis or framework carrying a wheelset and powered by an actuator, for example a combustion engine and/or electric motor.
Requirements of a bogie further include supporting the vehicle body, providing stability of the vehicle body, and countering noise, vibration and harshness (NVH) acting on the vehicle body.
These components are typically high-mass (and high-weight) components packaged densely within a bogie frame. It is desirable to provide isolation of functional parts from NVH and/or damage while maintaining a strong, supporting, balanced and energy efficient bogie. Further, particularly for light mass transit vehicles, a reduction in size and weight of a bogie is desirable compared with known heavy mass transit vehicle bogies.
There is, therefore, a need to provide a bogie for a light mass transit vehicle which alleviates one or more problems associated with the prior art.
Accordingly, a first aspect provides a bogie to allow transit as a vehicle, including: a bogie support frame including a first portion and a second portion, the first portion being mountable to form part of a vehicle in use; a suspension system connecting the first portion and second portion; at least one wheelset mounted on the second portion, each wheelset including two or more wheels mounted on a wheel axle; and an actuator for providing torque to the two or more wheels, wherein the first portion of the bogie support frame provides for location of an actuator. The vehicle may be a mass transit vehicle or a freight vehicle formed by one or more bogies.
The bogie may further include a transmission coupled directly to the actuator and the wheel axle.
The transmission may be mounted to the first portion such as a transverse member such as a bolster beam.
The transmission may be mounted along an axial axis of the wheel axle.
The transmission may be mounted centrally between two of the two or more wheels.
The bogie further includes a brake assembly.
The brake assembly may be mounted along an axial axis of the wheel axle.
The second portion of the bogie support frame may include an electrical induction brake.
The first portion may be above the suspension system.
The bogie may further include one or more small object deflectors.
The bogie may further include an electrical sensor for monitoring height of the first portion of the bogie relative to a first surface.
A controller may monitor and actuate the suspension system to automatically adjust the height of the first portion of the bogie to a predetermined height relative to the first surface.
A second aspect includes a vehicle including two or more of the bogies. The vehicle can be formed by each bogie or the bogies are secured to a freight container and/or a passenger cabin.
Further in accordance with aspect of the present invention there is provided a bogie which is independently operatable and controlled.
The bogie may have means for geo-positional determination and control. The bogie may have means for LIDAR ranging and positioning relative to the vehicle and/or other bogie along with collision avoidance.
Embodiments of the bogie are described, by way of example, with reference to the accompanying drawings, in which:
Referring firstly to
Referring to
The bogie (1) further includes a suspension system (12) connecting the first portion (111) and second portion (112). The suspension system (12) may include air springs. The air springs may connect the first portion (111) and the second portion (112). Air springs may provide the lowest eigen frequency. This may be advantageous to reduce noise, vibration and harshness, and stability, of the vehicle body.
Now referring to
Each wheelset (13) includes two or more wheels (131). The two or more wheels (131) are mounted on a wheel axle (132). The two or more wheels (131) may be resilient wheels. This may be advantageous to reduce NVH through the wheels. The two or more wheels (131) may each include a tyre. The wheel axle (132) may be mounted on the bogie support frame (11) via axle bearings (133). An axle bearing (133) may be included for each wheel (131). The bogie (1) may include two wheel sets (13), totalling two wheel axles and four wheels. This may be advantageous to drive the bogie in two directions and increase the stability of the bogie.
Now referring to
Referring to
The transmission (15) may be coupled directly to the wheel axle (132), thereby providing means for transmitting torque from the actuator (14) to the two or more wheels (131). This may be further advantageous to reduce mechanical losses and provide a more efficient bogie. The transmission (15) may be mounted centrally between two of the two or more wheels (131). This may be advantageous to balance the bogie and provide a more stable bogie. The transmission (15) may include a locked differential. This may be advantageous to rotate each wheel on a wheel axle at different speeds. The transmission (15) may provide a gear ratio reduction (from actuator (14) to wheel axle (132)) using gear combinations known in the art. The transmission (15) may be mounted above the suspension system (12). This may be advantageous to reduce NVH to the vehicle body, and provide a more stable bogie.
The wheel axle (132) may be a shaft of circular cross section. The shaft may be hollow or sold or partially solid. The shaft may define an axial axis and radial axis. The transmission (15) may be mounted along the axial axis of the wheel axle (132). This may be advantageous to be space efficient within the bogie.
The bogie (1) may further include a brake assembly (16). The brake assembly (16) may be mounted along an axial axis of the wheel axle (132). This may be advantageous to be space efficient within the bogie. The brake assembly (16) may include a brake disc (161). The brake disc (161) may be fixed to the drive shaft (141) or wheel axle (132). The brake disc (161) may be low noise and ventilated. This may be advantageous to provide cooling to the brake disc and reduce NVH to the vehicle body. The brake assembly (16) may further include electrically operated brake callipers (162). The brake callipers (162) may be operated remotely away from the brake assembly (16).
The bogie (1) may include one brake assembly (16) per wheel axle (132) or one brake assembly (160) per actuator (14). Further, the brake assembly (16) may include a friction brake. The second portion of the bogie support frame (112) may include an electrical induction brake.
The transmission (15) may be mounted above the wheel axle (132) and the drive shaft (141). This may provide an advantage that the brake assembly may be mounted on the wheel axle (rather than on the actuator) and avoid high NVH levels through to the vehicle body. This may require a dropped wheel axle (132) to take all loads between the two or more wheels (131) (that otherwise in a conventional solid axle arrangement is taken up by the wheel axle itself).
Accordingly, the drive shaft (141) may only be required to withstand the torque from traction and braking. This may provide the advantage of reducing the overall unsuspended mass (and weight), thereby providing a more space efficient, stable and/or durable bogie.
Now referring to
The wheelset (13) may include an inter-wheel frame. The inter-wheel frame may span from a first wheel (131) to a second wheel (131) and cover the wheel axle (132). Further, the inter-wheel frame may cover any equipment mounted on the wheel axle (132). This may be advantageous to protect equipment mounted on the wheel axle and provide a more durable and stable bogie.
The bogie (1) may further include one or more small object deflectors. A small object deflector may be provided for each wheel (131). This may be advantageous to remove objects in the path of the two or more wheels.
The bogie (1) may further include an electrical sensor. The electrical sensor may be a displacement sensor. Examples of sensors are optical and/or linear variable differential transformer (LVDT) sensors. The electrical sensor may be for monitoring height of the first portion (111) of the bogie (1) relative to a first surface. The first surface may be the ground and/or a platform. This may be advantageous by providing a more stable bogie.
The bogie (1) may include a controller. The controller may include executable instructions that may monitor and actuate the suspension system to automatically adjust the height of the first portion (111) of the bogie (1) to a predetermined height relative to the first surface. This may be advantageous to automatically adjust the floor height of the vehicle body between full load and partial load and no load.
The bogie (1) may include one or more guide wheels (201). Preferably, the bogie (1) includes four guide wheels (201). One guide wheel (201) may be mounted at each corner of the bogie (1). This may be advantageous for the guide wheels to act as a buffer to the whole bogie (1) and keep the wheels (131) on a track. The guide wheels (201) may be in continuous contact with a guide rail. The guide rail may guide a direction of the bogie (1) and vehicle (2). The guide wheels (201) may be mounted on the bogie support frame (11) via resilient elastic members, for example, springs. This may be advantageous to aid the continuous contact and reduce shock forces reaching the bogie support frame. The resilient elastic member may have an adjustable spring force such that when less buffering is needed (for example, on a straight section of track) the spring force is lowered.
The bogie (1) may include a switch wheel (202). The switch wheel (202) may be mounted on the bogie support frame (11). One or more switch wheels (202) may be included. The switch wheel (202) may be positioned outermost on the bogie support frame (11). The switch wheel (202) may move vertically to engage a track switch. A pneumatic switch wheel mechanism (203) may be used to move the switch wheel (202).
The bogie can incorporate an unconventional drive system mounting arrangement. The assembly is done in a simplified manner relying on a dampened pivoting control arm that is mounted to the transverse mounting pad or a first portion (111) and optionally a second portion (112) connecting both sides of the bogie. This also incorporates the mounting arm and damper for the gearbox. The transverse arrangement condenses the space required for the incorporation of the drive, including the brake set up. The advantage being the reduced size and weight of the overall system, serviceability of the system (clear space and ease of part assembly) and the potential if required to increase the power with a larger (wider) motor. The footprint of the mounting arrangement also giving a potential feature to add anti-vibration for certain ruggish applications.
Preferably, a transverse member, for example a bolster beam can be adapted as a first portion of the frame for the necessary equipment for drive, control and positioning to be configured and packaged onto the bogie.
A light mass transit vehicle (2) may include two or more bogies (1). This may be advantageous to provide more tractive force for a vehicle body (21). A first bogie (1) may be mounted at a first end of the vehicle body (21) and a second bogie (1) may be mounted at a second end of the vehicle body (21). This may be advantageous to provide a more stable and balanced vehicle body, and providing a suitable turning curve.
It will be appreciated that bogies in accordance with aspects of the present invention can be independent self-driving units to allow movement forwards and backwards. The bogies can operate autonomously and automatically in that each bogie has means for location, both geographically and relatively to other bogies and parts of the vehicle as well as to avoid collisions. In such circumstances each bogie can act as a skate upon which a freight container can be secured to act as a structural connection between skates to form a vehicle which can move along rails or with appropriately steerable wheels separately or a combination of both with separate wheels for use away from rails and flanged wheels for use with rails.
Typically, as illustrated in
The bogies will have their own control functions in the form of a processor or black box to control movement as well as positioning. The processor will have instructions for movement either under remote control or as destination objectives or for achieving train combinations. The processor will also act upon the positioning (geographical, relative and dimensional) to allow attachment of the container. As indicated it will be necessary to know the geographical position of the or each bogie so that the container or other vehicle assemblies can be first attached and then moved between such geographical locations. It will also be understood that the container or other vehicle assemblies may themselves be manufactured or positioned with some degree of error, for example the ground upon which the bogies are positioned may not be absolutely level or the fastenings slightly distorted so that the controller will then be able to adjust typically through an active suspension system the height and/or presentation angle of the connector surface of the bogie to the container or vehicle part to accommodate height variations. It will be understood once the container and bogie are robustly connected and secured such slight variations will be also accommodated by dynamic control by the processor in terms of a multitude of potential actions dependent upon how complex a control regime is required. For example, as the bogie moves curves in the parallel rails may with a substantially rigid container cause lateral stressing which the processor can accommodate as described above by turning slightly bogie wheels as well as adjustment of the connections between the bogie and container.
Furthermore, such control techniques can have an auto learning function in that normally several container and bogies as skates under each end of the container will be combined as units into a longer train combination which in some circumstances may be several hundred metres or even longer in length so that the bogies through their controller can communicate such that subsequent units (bogies and containers) will be aware of previous units actions in terms of curves in the track as well as ‘bumpy’ sections in the track so that the bogies can be configured in terms of suspension responses. In such circumstances, freight which is more fragile may be located towards the rear of the train combination so that the bogies via their suspension systems can absorb more shocks or in situations with mixed freight and passenger units the suspension ride can be dynamically adjusted accordingly. In any event with a black box controller any incidents or information with regard to the condition of the rails can be reported to a central maintenance function to be further investigated. The LIDAR function, if included may also allow for some form of rail surveying including with regard to tunnel walling in terms of variations in clearance etc.
With bogies of the type described above with regard to
The bogies 101, 102 can be independently moved forwards and back for local shunting or desired journeys.
As will be understood with a bogie to be used as a freight skate, it is more than desirable that the bogie has the ability to position the bogie within a centimetre or two of a reference marker and/or a partner bogie so that it matches with an autonomous loading crane and/or so ISO container if used.
There will be an autonomous retaining system in most advantageous embodiments of aspects of the invention, which engages the corner blocks or retracts when not needed. For example, a 10 ft container will need all four locators on a 10 ft frame (the default dimension of the bogie support frame, just a bit bigger than, for example the LN25 bogie). In the dual bogie situation for longer containers there will be a need these locators to retract and a central pair to appear so that the container is located across two bogies.
In accordance with aspects of the present invention substantially independent bogies 101, 102 are accurately positioned with a spacing 209. The bogies 101, 102 normally on the rails 201 can be independently driven (at least forwards and rearwards) for initial geographic positioning then more minute positioning for locking mechanisms In such circumstances, the bogies 101, 102 and in particular the power train (drive motors, batteries etc.) in the bogies 101, 102 can be charged in situ as required or the container 104 lifted in the direction of arrowhead A by a lift (not shown) so that depleted or nearly spent bogies are removed for recharging, maintenance and as required. Replacement bogies can then be located below the container 104 and the container lowered on to the replacement bogies so that the vehicle can rapidly return to use.
With regard to an autonomous bogie it will be appreciated that in addition to packaging of the components within a bogie frame envelope is to provide three elements, namely macro positioning to provided a base geographical location for the bogie, micro positioning to allow loading and placing of containers or for reliability with auto loader mechanisms and dynamic.
As indicated above to enable such movement each bogie or at least some of the bogies will have a number of features such as LIDAR mounted externally to vehicle on special brackets or mounted through a side of the vehicle possibly via ‘cut out’ access holes; RADAR sensor ideally mounted behind bumper of the vehicle although it is possible to provide a sensor which will ‘see’ through parts of the vehicle. There may further comprise means to isolate autonomy mode of the vehicle when not required. Although the vehicle will operate mostly in an autonomous state there will be an on board or remote safety driver. Potentially, it is envisaged that the autonomy control is used with standard or bespoke control processes and steps compatible with other vehicles for network control for each vehicle in autonomous control and/or in manual drive.
Vehicle software will be used to manage speed, braking etc. Speed signal will be supplied by autonomy software. Generally, GPS, triangulation of radio or other beams and dead reckoning by measuring movement from a known marker can be reasonably accurate but not sufficiently to allow accurate enough location for fastenings between the bogie and the other parts of the vehicle such as a passenger cabin or container so more accurate processes can then be used including LIDAR or similarly accurate processes/system to around 1 cm accuracy. It will also be understood that mechanical means such as tapered or funnel alignment openings to draw the fastening components together into alignment and/or more sophisticated docking software to control small movement of the or each bogie into sufficient alignment for coupling and fastening could be used.
The sensors used for GPS, RADAR, LIDAR as well as image cameras could also be used for dynamic control of the vehicle and bogies in motion to stop collisions with other vehicles/bogies as well as fixed objects, pedestrians, cyclists and other potential hazards.
A self-powered bogie used as a skate can initially be controlled by an operator using a remote control. The functions the bogie must include are as follows:
A self-driving vehicle comprising two or more bogies will ideally enable positioning between bogies which is managed autonomously. The main features are:
In one class of embodiments, a bogie is used which is motorised and reduced in weight incorporating a semi-suspended lightweight axial flux PM motor; IGW gearbox; electric-over spring emergency and parking brake; and lightweight wheelsets with hollow axles.
The propulsion system will be modular and adaptable and includes the option of a battery power pack incorporating one of more LTO batteries or NMC batteries. To optimise the duty cycle, a simple, safe fast charging system that sits between the rails in a designated charging bays can be used.
The bogie incorporates on-board battery monitoring and charge scheduling Range could be 100 km between charging depending on environment, battery and load. Battery choice will require a study of the daily operations within the freight terminal. With the automated charging system in theory, bogie could work on a 24-hour duty cycle, with charging breaks in between with optimum battery size and charging times. Furthermore this will enable calculation of the number of bogies or skates that will be required depending on the size of terminal and number of containers that pass through the facility.
The use of a bogie as a freight skate is a concept based around self-powered lightweight bogie. The light weight beneficially reduces wheel and rail damage in addition to noise reduction, and prolongs the battery duty cycle. Four-wheel drive assists with rail adhesion. The weight of the containers will also provide extra traction.
In view of the above the self-driving bogie or skate will, preferably, have the following main components installed into the underframe as follows:
While the invention has been illustrated and described in detail in the drawings and preceding description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments.
Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. Each feature of the disclosed embodiments may be replaced by alternative features serving the same, equivalent or similar purpose, unless stated otherwise. Therefore, unless stated otherwise, each feature disclosed is one example of a generic series of equivalent or similar features.
In the claims, the word “including” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. Any reference signs in the claims should not be construed as limiting the scope.
Number | Date | Country | Kind |
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2113401.0 | Sep 2021 | GB | national |
Filing Document | Filing Date | Country | Kind |
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PCT/GB2022/052374 | 9/20/2022 | WO |