Overview of Novel Multi-Functional Clutch Technology for EV Disconnects

so welcome back on our I said be a live stage and you know that we have a lot of international guests here on stage that are sharing their Keynotes with us and I think the longest distance there from our guests that are here is Australia but I would guess the second longest distance was made by my next guest he's coming from the US John Jennings is his name he's from amsted automotive and he will be on a stage after a short introduction by myself with the market growth of electric vehicles EV drivetrain systems are in the process of being redefined and reinvented as a part of the next generation of electric vehicle propulsion systems and Next Generation EV propulsion systems will need to be further optimized for function efficiency range and cost as the EV markets scale up so John Jennings will tell you their Solutions of amset automotive and how the company is facing these challenges great to have you here welcome thank you Mark and good afternoon everybody um as Mark said I'm here to talk about multifunctional clutch Technologies for electric vehicle disconnect systems for all-wheel drive so I'd like to start by introducing Amstead Automotive amset Automotive is part of anstead Industries a four billion dollar company with over 13 000 employees uh amsted Automotive was a new brand introduced in 2021. this was created by combining two companies of Amstead Industries means Industries and Burgess Norton and more recently smw Manufacturing sister companies within Amstead Industries include conmet and the commercial vehicle sector Amstead rail and BAC in the con in the construction sector I'd like to start by describing all-wheel drive systems with ice engine architectures here we see an example of a front-wheel drive-based all-wheel drive system with the internal combustion engine at the front powering ax power to both the front and the rear axles uh for an all-wheel drive system in this architecture the primary axle is the front axle the secondary axle is the rear axle a disconnect system is used to stop the rotation of the secondary axle for improved efficiency and in this case fuel economy the disconnect is accomplished through features within the PTU and the RDU which effectively stop the rotation when all-wheel drive is not needed so if the weather is nice like today the roads are dry and you don't need all-wheel drive this gives the opportunity to save energy and improve efficiency by disconnecting and stopping the rotation of the PTU the RDU and the prop shaft this stops all the gears from meshing all the rotating Parts the gears bearings seals and so on now if we compare this to an electric vehicle system you see a big difference in the electric vehicle system each axle has its own motor in this case an electric motor so the principle is the same during an all-wheel drive disconnect you stop the rotation of the secondary Driveline system in this case the rear drive line system and you stop the rotation of the motor itself there's some advantages with the uh EV architecture because each axle has its own dedicated electric motor this motor can actually be used to help synchronize and control the disconnect and reconnect of the system this in turn leads to new opportunities for new technologies to be utilized in electric vehicle architectures so I'd like to introduce our first application for an all-wheel drive disconnect system from Amstead Automotive this is a what we call our our DCC our Dynamic controllable clutch this is an electromagnetic actuation system and it's our first application of amsted's mechanical diode technology in a full EV application so this is disconnecting the rear axle on a North American Adventure vehicle this was launched into production last year so it's in its second year of production now basically how it works with the mechanical diode system and I'll shuttle back and forth so you can see how the struts engage and disengage so in this Condition it's in the lock mode all-wheel drive is functioning when the all-wheel drive is no longer needed because the roads are dry there's no need for all-wheel drive traction the system can disconnect by retracting the struts and now the input and output to the rear drive line is completely disconnected and the part stop rotating so in summary the response time of the system is very fast about 17 milliseconds or less than 20 milliseconds the system is efficient there's no friction elements it's all mechanical locking elements and the actuation system with the electromagnetic device is a bi-stable system that means power is consumed only during the shift that means in the 20 milliseconds of shifting this also allows for an ease of use compared to a typical dog clutch system where you have to be careful of block shifts there's no block shift possible with the system and the calibration and controls as such would be made easier to apply the torque in this case is over 2 800 newton meters with an ultimate torque up to 8 000 newton meters but this can be scaled as needed for the particular design application so as I said this was launched in production last year we found that with the very fast 20 millisecond shift time this would actually exceeded the uh the whole system shift time which was an order of magnitude slower so we started to think about what would be our next steps how could we help make the system and our customer applications faster as a system and easier to uh to actuate so this has led us to our next generation one-way clutch disconnect system the idea started with the idea of a bicycle and a one-way clutch so if you think about riding a bicycle when you pedal the bicycle you have forward power when you stop pedaling you Coast effectively you have an automatic disconnect when you want to apply power again you simply start to Pedal so how do we apply this now to an electric vehicle Driveline system well the principle is the same just like when you pedal the bicycle you can power the electric motor and get be connected and drive forward power you can turn the motor off just like when you stop pedaling and you automatically disconnect and you Coast or your free will when you want to power again you simply ramp up the e-motor and engage the system so there's no coordination of Disconnect actuator with the propulsion system now if we add a controllable one-way clutch for reverse and regen now we end up with what we call a bi-directional one-way clutch system so really this is enabled by the EV architecture with the dedicated e-motor and with the Amstead Automotive one-way clutch technology so how did we accomplish this well from left to right we took existing path of one-way clutch designs that are in production controllable one-way clutch designs that are in production and in combination with our DCC actuator which we launched last year we put these together as building blocks and we create a bi-directional one-way clutch system so on the right side we have the um the strut system for the passive one-way clutch for the forward propulsion and on the left side we have another set of struts that are controlled by the electromagnetic actuator for the reverse and Regen but what this ends up doing is providing three actual modes of operation for the vehicle system from top to bottom we have a disconnect mode you can see the struts are retracted this is freewheeling we have a forward power mode with the one-way clutch and thirdly we have reverse torque which provides the regen and the reverse actually you could almost call that a four mode operational function for those who like graphs what what this shows is how could some examples work so on the vertical axis is speed you can see here we're in disconnect mode the motor is at zero or idle the vehicle is moving so the wheel speed has some velocity and some RPM so at the moment when reconnect is desired you you turn on the motor you ramp up the speed and when the speed of the motor matches the wheel speed you automatically connect just like on your bicycle and now you're in power forward mode if you want to disconnect and go into all-wheel drive disconnect mode you simply turn off the motor ramp down the motor stops the drivetrain stops moving but the vehicle continues in two wheel drive basically similarly if we're in power mode at any time during this power forward mode the reverse struts can be engaged and the vehicle is ready for regen at any time that the driver releases the pressure from the accelerator pedal and you're in regen mode there's obviously many scenarios but here there's a couple just to illustrate how the how simple this system can work um an example use case application we have integrated the one-way clutch disconnect into a differential now it can be applied anywhere between the motor and the output of the gearbox and the differential we thought this was a nice application because when you connect or reconnect you're actually controlling the the torque and the power flow to both the left and the right Wheels um we have demonstration Hardware if anybody would like to look at that the parts uh we're in Hall six and you can see the example of this differential disconnect application so in summary um this system provides fast shift time so in the forward Direction it's automatic controlled by when the motor is powered or not powered and in the reverse regen you have the 17 millisecond response time um it's reliable meaning that there's no block shifts like is a an issue it can be an issue with some dog clutch designs and it's based on proven production core technology just reapplied for an electric vehicle application the smooth shifting can be accomplished through the motor controls of the propulsion motor controls there's less synchronization needed between the actuation of the disconnect and the propulsion motor so it really simplifies the uh the smoothness and the Simplicity of the controls there's no friction devices as mentioned so the there's a high efficiency and it's flexible to be packaged within the drivetrain as I mentioned it offers three or even four modes of operation and um as mentioned the Simplicity of the controls let's say provide less complications and less fewer failure modes and because of the higher reliability of the block shifts not being possible this also enables the potential of disconnecting a primary axle and be very interested to discuss this point with anybody interested but this would enable a sailing mode to further increase the efficiency of the energy and the range so in summary I gave you a little overview of our new disconnect systems with the one-way clutch integration we also have Technologies where we've integrated Park lock functionality into the system which is an option and we're very involved in applying the same one-way clutch technology as a shift system for two-speed power shift and for multi-speed shift systems utilizing the one-way clutch as a transitional feature this is a subject in itself and will be a future presentation thank you for attention and I'd like to invite all of you to come visit our booth and Hall six today [Applause]

Channel: Amsted Automotive

Views: 179,461

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Id: iQ75TOOYYKU

Length: 14min 39sec (879 seconds)

Published: Tue Feb 07 2023