Electronically Sign School Supply Order Invoice Made Easy

Electronically sign school supply order invoice

[Music] hello i'm professor john kelly and this is the weber auto youtube channel today we are coming to you from our brand new building on the weber state university davis campus in layton utah now today we are going to talk about the trans axle the hybrid transaxle that comes in the 2019 and above toyota rav4 hybrid so this transaxle is called the p710 transaxle and it is just a little bit larger version of the p610 transaxle that comes in the 2016 and above toyota prius this is not the same transaxle that comes in the the toyota rav4 prime it uses a p810 transaxle and we'll talk a little bit more about that later in this video i should also mention that this p710 transaxle comes in a 2018 and above toyota camry hybrid toyota avalon hybrid and a lexus es 300h this transaxle is coupled with a very fuel-efficient 2.5 liter atkinson cycle engine this is a very special engine that has a very high brake thermal efficiency rating which means that it can convert almost 40 of the heat energy that it produces into mechanical energy now that may not sound very good but for an internal combustion engine that's really good but in order to do that it needs to operate within certain rpm and load ranges and this transaxle can help it do that so let's take a look at the parts inside this transaxle that help that engine maintain its optimum efficiency so this transaxle has two electric motors the electric motor that helps move the vehicle down the road is called motor generator number two this big motor right here and so it connects to a gear shaft right here called the motor speed reduction gear shaft and it has 16 teeth on it and i will set that down in the trans axle case right here and then the electric motor mg2 sits right on top of that there we go now that 16 tooth gear that this motor turns meshes with a counter drive gear right here this counter drive gear has 49 teeth on it and it drives the pinion gear of the final drive and so we'll put this down in here like that the gear ratio between motor generator number two and this counter gear right here is 3.0625 and we get that by dividing the 49 teeth of the counter gear by the 16 teeth of the motor reduction gear now this counter gear with the pinion gear on the top drives the differential assembly and like any other transmission front-wheel drive transmission we have a differential to allow the front wheels to turn at different speeds while you turn a corner so i'm going to set the differential case with the ring gear on it down inside here now there we go this ring gear on the differential case on the rav4 hybrid has 78 teeth and the pinion portion of it has 20 teeth that gives us a gear ratio of 3.9 to 1 between the counter gear and the ring gear on the rav4 if it's the camry or the avalon or the lexus cs300h then there are 22 teeth on this pinion and only 76 teeth on the ring gear and that gives us a gear ratio of 3.4545 so what we are looking at right now is a motor an electric motor this is the rotor of the motor it sits inside of a stator back here in this transmission case and the rotor rotates in this direction to make the vehicle move forward so this is the front of the vehicle back here this differential has the cv half shafts connect to it and through your hub and bearing assemblies your tires and wheels and so when you see this gear right here rotate just think of that as your front tires because it rotates the same speed as your front tires now the overall gear ratio between this motor generator number two and your tires to make them rotate one time uh on the rav4 is 11.944 to 1. in other words it takes 11.944 rotations of this motor mg2 to get one rotation of your tires now if you've got the camry or the avalon or the lexus es 300h then it's only 10.58 uh revolutions of mg2 to get one revolution of the tire the rav4 has more because it gives you a little bit more torque a feeling of more power well it is more power it's torque multiplication uh in the rav4 than you would have uh on the the passenger cars this motor is rated at 88 kilowatts which is roughly 120 horsepower it's also rated at 202 newton meters of torque which is approximately 149 foot-pound-force of torque and it has a maximum rpm of 17 000. these really spin fast and they spin fast uh because they use less permanent magnets in here less of the rare earth permanent magnets and so to make up for lower power motors lower power rotors they spin them faster at lower gear reductions or higher numerical gear reductions to get approximately the same power as the older hybrid transaxles that had the stronger magnets in them the rav4 hybrid does have a rear electric motor i don't have that here with me if i can get my hands on one we'll take a look at one in a future video all right so the final drive differential right here in ring gear can receive power from mg2 as you're driving down the road under any operating condition it's either receiving power from the motor spinning as receiving power from the stator and the inverter assembly under the hood or when you decelerate the wheels and tires through the cv half shafts turn the differential case here which force forces the mg2 rotor to spin and in this case it becomes a generator so that's where you can pick up some regenerative braking so mg2 is either a motor as you're accelerating or trying to hold a steady speed or it can become a generator when you decelerate all right now that's one of two paths for power to get into the differential ear to move the vehicle down the road the other path comes from the engine through the second electric motor that this transaxle has so this transaxle has another electric motor right here called motor generator number one and motor generator number one is not used to propel the vehicle down the road but instead it is used with a planetary gear set that toyota calls the power split device to control the gear ratio between the internal combustion engine crankshaft and the counter gear in the final drive gear right here so let's take a look at this planetary gear set every planetary gear set has a ring gear like this one right here sometimes it's called an internal gear or an annulus gear but you can see it inside of there this ring gear has 78 teeth all toyota hybrid power split device ring gears have 78 teeth every single one of them then we have a what's called a planet carrier so we have these little planet gears right here there's three of them this piece that holds them or carries them is called the planet carrier and it splines directly to a special torque limiting clutch pack that connects to the engine crankshaft so what that means is this planet carrier spins with the engine crankshaft at exactly the same speed as the engine crankshaft so that sits inside of this ring gear and then we have a sun gear right here this sun gear has 30 teeth on it just like all toyota hybrid transaxles have 30 teeth on the on the sun gear uh 78 teeth on the ring gear and 23 teeth i believe on the planet carrier or on the planet gears all right so this sun gear connects directly to the mg1 electric motor back here so we have three pieces of the planetary gear set the ring gear on the inside is actually connected to a this housing that has a counter drive gear on the outside and that counter drive gear has 53 teeth on it and so the counter drive gear spins with the planetary gear set ring gear and it drives the counter gear right here that turns our pinion and ring and makes the vehicle move down the road so if this gear rotates the vehicle will move so let's set this down in the in the transmission now so next we take our planet carrier and put it down in the ring gear the input shaft that hooks to the engine is going to go through into the bell housing underneath here and so we will put this down in get the gear teeth lined up and down it goes and then we'll take our sun gear with its 30 teeth and put it in the middle of that planet carrier and get its teeth lined up and we've got a few bearings right here that go with it and then finally motor generator number one oh before i put on motor generator number one this transmission like almost all toyota hybrid transmissions has a mechanically engine mechanically driven oil pump so there's a drive shaft that connects to the planet carrier and spins with the engine that drives an oil pump in the in the side cover of the transmission so i just wanted to show you that on the planet carrier before we put the motor on but now let's put motor generator number one up here and we will spline it right to that sun gear so now if the sun or if the electric motor mg1 rotates the sun gear rotates because they're splined together the sun gear with the electric motor here the planet carrier is turning and it takes 3.6 revolutions of this motor generator number one to get one rotation of the planet carrier or the one rotation of the engine crankshaft so one of the jobs of the mg1 motor is to start the engine and it just simply does that by turning faster than the planet carrier and it takes 3.6 rotations of motor generator one to get one rotation of the crankshaft and that's with the vehicle stopped so these little bumps right here on this on this gear those are the part that is the parking gear and we have a parking pawl right here here's the parking pawl and a little pin holds it in place and when you put the transmission in park this moves forward and latches into the parking gear and that prevents the ring gear from rotating that also prevents the counter drive and counter driven gear and final drive gear differential from rotating which means the vehicle won't move so we'll take it out of park further our demonstration here but uh mg1 has several jobs as as i just showed you it can start the engine now i showed you right there how it would start the engine with the vehicle stopped but you it can start and stop the engine at any vehicle speed it just needs to spin at the appropriate speed to start the engine based on the vehicle speed and the rpm of all these other parts all right the second thing that motor generator number one does is it generates power to recharge your high voltage battery uh it also generates power to feed power to motor generator number two under certain conditions and that would be considered a series hybrid operation at that point if we have an engine driven generator providing power to the motor that propels the vehicle down the road so it once again it generates power to charge the high voltage battery this does not generate power to charge the 12 volt battery the high voltage battery provides power to a part called the dc to dc converter which charges your 12 volt battery this vehicle does not have an alternator so there's a that's a common point of confusion with the mg 1 here is which battery does it charge and it's just the high voltage one and then one of the biggest jobs that it has is to provide a variable gear ratio between the engine crankshaft and our counter shaft and final drive here so right now if i were to reach under this transaxle and get up and grab that input shaft right that i showed you on the planet carrier and try to try to rotate it i i can rotate it and notice with the vehicle stopped with us in park all that does is spin motor generator number one three point six times faster than the than the engine and under those conditions it can be a generator or could just be neutralized and free spin but notice it's not making the vehicle move this ring gear is not rotating the vehicle is not moving so in order to make the vehicle move uh with power supplied from the engine motor generator number one we play some tricks with motor generator number one's rotational speed and direction of rotation so in any other automatic transmission that you drive uh it has low gears and high gears a low gear it would be considered an under drive gear under drive gear ratio and what that means is that the engine is spinning faster than the output shaft of the transmission to drive the wheels the engine crankshaft is spinning faster then there's another situation called direct drive where the engine crankshaft is spinning the same speed as the output shaft of the transmission and then there's another condition called overdrive where the engine crankshaft is spinning slower than the output shaft of the transmission this power split device planetary gear set that we have right here can do all three of those and have variable infinitely variable gear ratios in between and so i want to walk you through the different modes of operation that this ecvt electronic continuously variable transmission has there are nine different modes of operation this is a cvt but it is not one of those belt driven either the push build or the pull chain style cvts that you read about in other vehicle manufacturers or even in other toyotas this is a much more reliable but more expensive way of accomplishing the same thing so let's walk through the nine different modes of operation of the ecvt transmission okay mode number one we are in park vehicle at a stop the vehicle is off and you reach in step on the brake pedal and hit your power button and your ready light comes on on the dash at that point the engine might start it might not start it just depends on the state of charge of the battery the high voltage battery so if it does start i just showed you how mg1 right here will rotate 3.6 times for each revolution of the engine crankshaft and it'll rotate at a high speed to get the engine started very quickly so once the engine starts then we enter mode 2 which is charging while stopped so with the vehicle stopped engine running the engine is spinning the engine crankshaft is spinning the planet carrier mg1 spins 3.6 times faster than the engine crankshaft and acts as a generator as needed you may have noticed that the engine will shut off after a while then it'll start again it'll shut off start again it's doing that to recharge the high voltage battery the battery state of charge will come down to a certain point engine starts uses mg1 to recharge the high voltage battery once it reaches a certain state of charge then it shuts the engine back off and it'll sit there cycling for days if you let it do that i've left vehicles on over the weekend left on a friday come back on a monday and all of a sudden a prius engine fires up and it's like oh i forgot to shut that off but anyway that's start that is charging while stopped mode three now is we take it out of park put it in drive and we're ready to take off to start driving at low speeds under those conditions the engine could be off let's say that the battery's state of charge is high so when it's high it the battery will through the inverter will provide power to mg2 and propel the vehicle and so it will turn mg2 just like this notice that causes mg1 to also rotate what you cannot see is that the planet carrier or the engine crankshaft is not rotating and this is just the electric vehicle mode and depending on the battery state of charge you can drive up to a certain vehicle speed uh as long as you accelerate slowly before the engine comes on to assist with that so so in mode number four the bat the high voltage battery state of charge is getting low and that battery provides power to mg2 to keep to propel the vehicle but if the battery state of charge is low then we need to start the engine and so mg1 starts the engine when the engine is running i'll spin the crank the equivalent of the crankshaft here the transmission input shaft that planet carrier notice now the speed of mg1 has picked up it's faster and that's because it's acting as a generator to supply power to the battery and to supply power to the mg2 rotor to help move the vehicle down the road okay mode number five is called constant speed cruising and under those conditions under low load so you're not going up a hill you're not going downhill you're just going on a nice flat surface under those conditions the ecvt portion of our planetary gear set here tries to let the engine rpm go to the point where it is the most fuel efficient for the existing load and vehicle speed that the vehicle is experiencing if you look at this table right here this is from a report published in 2019 from the epa the u.s environmental protection agency they did a study of the thermal efficiencies the brake thermal efficiencies of several different engines and one of them was this 2.5 liter engine used by toyota and if you notice there on the chart it has a maximum brake thermal efficiency of 39.8 percent now in that at that 39.8 mark you'll notice that the engine rpm at the bottom of the screen is approximately 2500 and the amount of torque in newton meters off to the left of the screen is 180 which is about 133 foot pound force of torque and then notice at the same time that red arc coming down to the 50 kilowatt uh text there on the right hand side of the graph indicates that the 39.8 percent of brake thermal efficiency is occurring while delivering 50 kilowatts of power 50 000 watts of power well we don't need 50 000 watts of power when we're just at a steady state cruise speed we need less than that it might be as low as 30 kilowatts of power so if you look at this next chart i have marked the lowest engine rpm and the highest engine rpm that we could use and still be at 39 brake thermal efficiency i've also marked the highest torque and the lowest torque so between 190 newton meters and 140 newton meters of torque we will still be in that 39 thermal efficiency range and that also if you look on the right hand side of the graph gives us anywhere between 25 kilowatts of power which would be like for steady state cruising clear up to 265 kilowatts of power okay let's see how the planetary gear set or the power split device as toyota calls it helps the engine stay in that operating range that maximum efficiency operating range that we just looked at on the chart so if we look at the relationship between the rotational speed of the mg1 rotor which is the sun gear the engine crankshaft which is the planet carrier and the ring gear here which is our counter drive gear we can achieve and see how underdrive direct drive and overdrive occur so in underdrive which is what we want when we're accelerating we want a low gear ratio we just spin mg1 faster than we spin the counter drive gear and the larger the difference between the speeds of those two parts the higher numerically the gear ratio is and you get really good acceleration but as vehicle speed starts to increase we bring the rotational speeds of these two closer and closer together until eventually they become the same speed now at that point which in our example at 104 kilometers per hour or 65 miles per hour that occurs at 1650 engine rpm on the rav4 hybrid and so at 1650 the sun gear the planet carrier which is the engine crankshaft and the counter drive gear all spin together as one assembly now once we want to go a little faster and get into overdrive gear then we slow down mg1 to where it's spinning slower than the ring gear or counter drive gear here so we we spin slower than the than the ring gear here and that forces it to go into an overdrive situation and eventually we will get to a point where mg1 actually stops rotating while you're driving down the road and at 65 miles an hour that actually occurs at 2109 engine rpm so if you're driving 65 miles an hour your engine rpm hits 2109 this motor physically stops moving and that puts if i turn the engine crankshaft here that causes an overdrive situation to occur between the planet carrier and the ring gear here then if we want even more overdrive since the motor stopped and it was spinning in one direction now we will spin it in the opposite direction so all of this time the under drive gear ratios we were spinning the motor in the same direction as the ring gear down below but when we stop and and want to go into more overdrive we turn it in the opposite direction so now they're spinning opposite directions and that gives us an overdrive situation so if we want to under drive we just spin mg1 faster than the ring gear if we want direct drive we spin at the same speed if we want overdrive we spin it slower than the ring gear and slowed down to a point where it physically stops and then we can turn it backwards to force an even higher overdrive gear ratio for maximum fuel efficiency by and what that does is it allows the engine rpm to be controlled by the rotational speed difference here transferring torque to our final drive all right this also has a maximum rpm of 17 000. it can produce approximately 31 kilowatts of power in generation mode which is about 42 horsepower it has about 54 newton meters of torque or 40 foot pound force of torque okay so that was mode 5 of 9 which is steady state cruising in mode 6 we have steady state or constant speed cruising but with a low state of charge in the high voltage battery and in that case we just speed up the engine to force mg1 to spin even faster to provide power to the high voltage battery that then supplies power to mg2 at the same time and at that time there's a combination of power being delivered to the final drive through mg2 through the counter gear to the final drive and not only are we generating power by spinning the engine faster here for mg1 but some of that torque is also delivered from the engine to our counter gear to the final drive so we have two separate paths for power to be delivered to the final drive here okay mode number seven is full throttle acceleration and under those conditions the high voltage battery supplies extra power to the inverter to help mg2 have all the power that it can electrically and then the engine goes to an under drive gear ratio through the planetary gear set here to also help provide power and we get maximum output potential from mg2 and maximum output potential with a variable gear ratio out of mg1 through the planet or through the power split device to our counter gear to the final drive mode number eight is deceleration when you let off on the throttle when you are driving down the road mg2 which has been a motor up to this point now becomes a generator and it will induce current into the mg2 stator back here and send power back to the battery if the battery state of charge is low enough and and needs it uh under those conditions there's some physical resistance to rotating the mg2 rotor uh caused by like uh magnetic fields opposing each other as it rotates uh and that gives you not only regeneration of power but regenerative braking it helps slow the vehicle the same thing can occur when you move your shifter to the b or braking position on this vehicle all right mode 9 is just simply reverse and we've talked about that already we just turn the electric motor in the opposite direction so that's reverse right there here's forward no reverse gear we just turn the motor uh backwards all right let's let's take a look at the rotors here just for a moment there are three different trans axles in this series that look very much alike there's the p610 that's in the prius the p710 that we're looking at right now and then the p810 that comes in the the rav4 prime it's in the new sienna uh van and it's in the highlander hybrid um by comparison the p610 in the prius has a rotor mg1 rotor same diameter but it's 24.3 millimeters thinner the rotor the mg2 rotor in the prius is 10 millimeters thinner than this one but if we talk about the p810 transaxle in the rav4 prime we've got jets flying overhead right next to an air force base it's there's always something if we talk about the p810 mg2 rotor in the rav4 prime it's actually 36.5 millimeters thicker than this one but with the same diameter and its mg1 rotor is the same thickness as this one so that will give the mg or the p810 in the rav4 prime and the highlander and the sienna more power which it needs because those are bigger heavier vehicles and if you're driving in ev mode only on the rav4 prime you don't have the additional power coming from the internal combustion engine to propel the vehicle so you need a more powerful electric motor to give you the same feel to give you the same acceleration if not more than you had with the internal combustion engine let's get the motors out of the way just for a moment we're just about done let's take a look at the stators the rest of the transaxle case right here all right this right here is a stator for mg2 and this is a stator for mg1 and each of these have three wires you can see down inside here there's six there's five right here a sixth one over there there's six bolts there are three wires there are three phase cables for each of these stators and the stators are what have current going through them that produces a magnetic field that attracts and repels the permanent magnet rotors that are in the transaxle and and makes them rotate these stators get very hot and so they are liquid cooled by the transmission fluid the toyota world standard transmission fluid it has spray cooling there's a tube right here and a tube right here and this is the top of the trans axle i've got it upside down but it sprays transmission fluid on to the windings in the housing and the stator frame to help cool it with the transmission fluid it has temperature sensors there's one right here and one right here one for each of the two stators this has an oil pump as i mentioned before it has an oil pump pickup tube right here in the bottom of the transmission and then the oil pump itself is in the front cover or the side cover of the trans axle so here's the the side cover and if you look right there is the identification the p710 transaxle and the oil pump that's driven off of the engine crankshaft through the planet carrier has its drive shaft sticking through right here and rotates with the engine crankshaft at engine speed these two pieces right here are called resolvers and they are the parts that measure the rotational speed direction of rotation and position of the mg1 and the mg2 rotors over there these are serviceable you have to replace them as a set and then there's a scan tool function to go in and have it auto learn the position of the the rotors actual magnetic pulls to the uh reluctors here in the side case there's one more thing i want to show you about this transaxle and that is uh these six wires right here there's three wires right here for the mg1 stator and three wires right here for the mg2 stator and these are where the current and the voltage are supplied from the inverter assembly that's on top of this transaxle under the hood now these wires are fairly thick and they're a lot thicker if you look at this photo here in comparison with the p610 the prius transaxle uh transfer wires and i assume that the p810 wires are even thicker it's just an indication of how much more power electrical power each transaxle uses the p610 not using near as much as the p710 the p810 going to use even more all right as i mentioned before the rav4 hybrid has a rear axle it's actually called the q610 i'll try to get my hands on one of those and i'm still looking for and always looking for the p810 but it's so new it's they're hard to come by and as soon as i get one i'll tear it apart and show you what's inside of it as well thank you for watching [Music] [Applause] [Music] [Music] you