usage of denso window motor [Archive]

ttldomination

11-01-2011, 19:54

Where can we buy a sprocket that will work with the window motor coupler? OR, can someone explain other possible ways to connect the window motor with the drive chain?

Thanks, Team 3328

What my team has done is taken the cone shaped outside part of the coupler and ground away some of the material. This allows a 1.125" sprocket to slide in there nice and snug. Screw in the sprocket and you're set.

Also, the output shaft is a 8mm key shaft. You can purchase this shaft from AM or another provider and use the 8mm key AM hub found here (http://www.andymark.com/searchresults.asp?cat=215), and attach a sprocket to that.

Hope that helps,
Sunny

DonRotolo

11-01-2011, 22:01

In years past we have also cut off the cone part and bolted a metal plate to the wide flange of the adapter, and run stuff off that.

Just remember that the plastic, although strong, has its limits. Have spares available and make them easy enough to replace!

vincentkee

14-01-2011, 23:53

Does anyone have experience with putting two or more Denso motors to power the same shaft?

From what I heard, the Denso motors have a worm gear and are thus cannot backdrive. If you use more than one Denso motor on a shaft, since all motors vary in speeds and the Denso cannot backdrive, will the Densos end up twisting the shaft?

Thanks

KHall

15-01-2011, 00:10

Does anyone have experience with putting two or more Denso motors to power the same shaft?

Yes, we did something like that last year. We used two motors on a single shaft to form a winch that wound our kicker's spring. Worked fine.

If there was any difference in speeds, well, we let the motors work that out. The winch lasted all season and we never had issues with it.

We used spikes to drive the motors. I can't recall if we were able to use a PWM splitter cable or if (spin) direction differences caused us to need two separate PWM ports. But its probably a good idea to work out which way everything turns before you assemble it. We did blow the fuses in the spikes a couple times when the kicker locked up, but the winch just kept working.

Keith Hall
Mentor 2171

Stephen of REX

15-01-2011, 00:15

Window motors can run backwards as well as forwards. Last year we had four window motors working in tandem to winch the robot up onto the tower. Just make sure to always run them at the same speed.

Creator Mat

15-01-2011, 00:25

Where can we buy a sprocket that will work with the window motor coupler? OR, can someone explain other possible ways to connect the window motor with the drive chain?

Thanks, Team 3328

What we did to attach the coupler with the was pin it to the window motor using a cotter pin. It stayed pretty well and we never had any problems with it

artdutra04

15-01-2011, 01:32

If you have access to CNC machines (through your shop or via sponsors), you can machine your own sprockets. The Denso motors also do not like cantilevered loads, so you should always support the shaft with another bearing/bushing. Here's some 7075 aluminum sprockets with a Denso hub pattern that I machined last year for 228.

http://www.team228.org/gallery/126/slideshow/img_93eb1-ac00d.jpg (http://www.team228.org/media/pictures/view/6159)

http://www.team228.org/gallery/126/slideshow/img_1b368-75415.jpg (http://www.team228.org/media/pictures/view/6168)
The Denso motor, sprocket, and shaft support (with Delrin bushing).

Lowfategg

15-01-2011, 02:28

We turned down the included KOP hub and machined the inside to press fit a bearing that would fit over the fixed metal idler shaft on the motor (I think it was 5/16"). I drilled and tapped the end of the shaft on the motor (your allowed to modify the output shafts on motors <R47>), and held it all together with a number #10 screw and washer. You can just bolt whatever you like to the modified KOP hub. Just be careful with side loads because the metal shaft on the motor is not well supported.

We used this on our ball pinching system last year with V-belts. It was a low torque application and it never failed.

http://lh4.ggpht.com/_td0eEyrujD4/TTFL2vMkS_I/AAAAAAAABl8/RSq4cPtXho4/Window%20Motor%20Sprocket.jpg

Gdeaver

15-01-2011, 08:11

We took a 3/4" sprocket and epoxied it onto the motor. Had to ream out the sprocket hub a little. If your varying the speed of the window motor you should use a victor speed controller not a jag. If you experience random lock up remove the locking pins.

ttldomination

16-01-2011, 15:45

Turns out that the output shaft of the couplers that come with the kit are not 8 mm like the Andy Mark hubs, but instead, they are about 16 mm, or about .63". Would it be wise to take a .625" AM hub and sand out the inside a bit to make it fit on the shaft?

Team 3355 Ment

17-01-2011, 22:06

What we did to attach the coupler with the was pin it to the window motor using a cotter pin. It stayed pretty well and we never had any problems with it

Would you happen to have a picture of your set up?

heathput

22-01-2011, 20:53

How much are we allowed to modify the window motors/gearbox? Can we use the gearbox for another motor?:yikes:

NyCityKId

23-01-2011, 15:58

How much are we allowed to modify the window motors/gearbox? Can we use the gearbox for another motor?:yikes:

reference rule <R47>

mathking

23-01-2011, 17:32

We had success taking off the star pattern hub on the Denso shaft, using a lathe to bore out a hole in a 5/8" shaft and then "pinning" the 5/8ths shaft to the Denso shaft by drilling a hole and using a screw. I will see if I can find that setup tomorrow and take a picture. But if you have the machining capabilities sprockets like artdutra04's seem like a good way to go. Very nice!

heathput

23-01-2011, 18:54

reference rule <R47>

Rule <R47> talks about modifications to motors. If I understand the rule, I can remove the motor, leaving the gearbox. Then I can mount a different legal KOP motor to the gearbox. It would require an adapter, but would be legal. Does anyone think I am off base?:rolleyes:

NyCityKId

23-01-2011, 20:27

Rule <R47> talks about modifications to motors. If I understand the rule, I can remove the motor, leaving the gearbox. Then I can mount a different legal KOP motor to the gearbox. It would require an adapter, but would be legal. Does anyone think I am off base?:rolleyes:

As long as the motors you plan to use are in accordance with rules <R45> and <R46>, it should be OK as far as I know, but I don't really see why you would want to. Furthermore, I wouldn't want to be the one to have to figure out how to securely attach a bane bots motor to a window motor gearbox.:p

heathput

23-01-2011, 20:46

Vikesrock

23-01-2011, 20:50

I believe in past years the Window Motor gearboxes have been ruled to be integral to the motor and covered by the equivalent of <R47>.

If you want to use the gearbox with a different motor I highly recommend posting to the Q&A for clarification. I think it would be legal to use the gearbox with a different motor, but not the motor with a different gearbox.

NyCityKId

23-01-2011, 23:11

Think about it. The window motor gearbox is small and has mounting holes so it is easy to mount. The motor is pretty wimpy though. A 775 banebot turns only slightly faster, but has a much higher stall torque. By my calculations the window motor on the gearbox can produce about 90 inch pounds of torque at stall. With the banebot on the gearbox the number is a little more than 300 at stall. I do not think the plastic gears will hold up to 300, but I can run the motor at less than half the stall and still lift a boat load.:ahh:

Well if your numbers are correct then I can see why you would want to switch. I personally feel that you might be taking the difficult route by trying to switch motors since there are other ways to increase torque other than switching motors. However since I don't know how you plan to use the motors I cant say whether your going overboard or not. In any case, like Vikesrock said, the best place to post a question like this the Official Q&A forum.

If you don't mind though I would love to see how the motor swap turns out though, assuming the GDC says its OK.

heathput

23-01-2011, 23:57

I am going to try the swap anyway and see what happens. I will let you know how it goes.

ratdude747

24-01-2011, 07:02

good luck. in the past two years i have been on two teams that tried it... the motor has the worm molded into the the motor's shaft. you would have to either fashion the shaft into a press-on for the motor or machine a new piece.

i would not mess with it, just me $0.02.

yara92

24-01-2011, 09:04

Can you plese send me the cad for this photo

clayman

25-01-2011, 17:10

The CAD for those custom sprockets would also help our team a lot (we currently have no CAD skill).

artdutra04

25-01-2011, 17:54

Attached is a STEP file of the sprocket I machined in the photos above. All I did was download a regular sprocket model from McMaster-Carr (they have CAD models for most of their hardware (screws, nuts, shoulder bolts, sprockets, etc) on their website), use calipers to measure the metric output "spline" of the Denso motor, draw it on the part, and extrude cut it.

To machine it was a four step process. The first thing I had to do was machine a fixture plate out of 6061 aluminum. Then I machined about 90% of the sprocket features onto the 1/2" 7075 aluminum raw material. Then I took that part out, bolted it to the fixture plate upside down (http://team228.org/media/pictures/view/6156), and machined the sprocket teeth into it (http://team228.org/media/pictures/view/6157). The last step is to use a lathe or hand file to bevel the teeth.

There is nothing in this CAD model to keep the sprocket on the shaft of the motor or to support it for cantilevered loads. In the second photo I previously posted, our solution was to machine a custom bushing out of Delrin to both support the shaft and to keep the sprocket laterally in place on the shaft.

JRysenga

26-01-2011, 12:52

reference rule <R47>

We have been debating the same question... Can we use the worm gear transmission only? If you remove everything related to the motor (armature, brushes, wires, etc.) you are left with a nice input shaft to drive the worm gears. Why couldn't we use another (un modified) motor to drive this transmissioin? R47 talks about "modifying" motors. We demolished the denso motor and threw it away! R47 also states, "The intent of this rule is to maintain the maximum power level for each ROBOT" We didn't change the maximum power level since we plan to use another (legal) motor from the kit to drive the worm gears. Think we would pass inspection?

NyCityKId

26-01-2011, 20:00

We have been debating the same question... Can we use the worm gear transmission only? If you remove everything related to the motor (armature, brushes, wires, etc.) you are left with a nice input shaft to drive the worm gears. Why couldn't we use another (un modified) motor to drive this transmissioin? R47 talks about "modifying" motors. We demolished the denso motor and threw it away! R47 also states, "The intent of this rule is to maintain the maximum power level for each ROBOT" We didn't change the maximum power level since we plan to use another (legal) motor from the kit to drive the worm gears. Think we would pass inspection?

To the best of my knowledge and understanding of the rules taking apart a gear box or transmission should be perfectly OK as long as rules <R47> and the rules on COTS items are followed. They don't have any specific rules governing gearboxes and they're uses. And there is also this: This intent is clearly met when a team obtains a MECHANISM or COTS items that was designed for non-FIRST purposes, and then modifies or alters it to provide functionality for the ROBOT. For example, if a team obtains a gearbox from a power drill and modifies it to use on the ROBOT, they gain insight into the design of the original gearbox purpose, learn to characterize the performance of the original design, and implement the engineering design process to create their customized application for the gearbox. According to that excerpt, taking apart a gearbox and using it in an innovative way is perfectly acceptable. This, however, is only speculation. If you want a final answer you should post this question to the official Q&A and see what the GDC has to say.

yara92

27-01-2011, 08:27

My team 1946 thank you for your help

cilginbilgin

27-01-2011, 14:40

Hello can anyone suggest us to use window motors without using gears

PAR_WIG1350

27-01-2011, 17:33

Hello can anyone suggest us to use window motors without using gears

I'm sure many people (myself included) would be more than happy to help, but the question seems a little unclear.

If you want to remove the stock gearbox from the window motor in order to use the motor, this would be illegal since it is integral to the motor <R47>.

If you want to use the window motors with the stock gearbox and nothing additional, this would be fine, all you would need to do is mount the mechanism to the adapters provided in the kit. The only thing you would need to worry about is stripping the teeth of the gears.

If neither of these two answers match the question, rewording the question might help.

eedoga

27-01-2011, 21:44

If your still interested check out this photo gallery. We cut two plates using aluminum, and then got spacers to put in between them We drilled holes in the black plastic thing, and bolted a gear to that. We then put the top plate on holding the plastic thing in place.

http://forums.trossenrobotics.com/gallery/showimage.php?i=3734

http://forums.trossenrobotics.com/gallery/files/1/4/9/9/2011share_-_4_original.jpg
http://forums.trossenrobotics.com/gallery/files/1/4/9/9/2011share_-_3.jpg

I included an STP file as an attachment.

Edoga
2980

Steve Compton

03-02-2011, 07:21

Hey Arthur, Nice work! Do you have any kind of CAD file you could share?

If you have access to CNC machines (through your shop or via sponsors), you can machine your own sprockets. The Denso motors also do not like cantilevered loads, so you should always support the shaft with another bearing/bushing. Here's some 7075 aluminum sprockets with a Denso hub pattern that I machined last year for 228.

http://www.team228.org/gallery/126/slideshow/img_93eb1-ac00d.jpg (http://www.team228.org/media/pictures/view/6159)

http://www.team228.org/gallery/126/slideshow/img_1b368-75415.jpg (http://www.team228.org/media/pictures/view/6168)
The Denso motor, sprocket, and shaft support (with Delrin bushing).

Steve Compton

03-02-2011, 07:23

opps - there it is, thanks!

Attached is a STEP file of the sprocket I machined in the photos above. All I did was download a regular sprocket model from McMaster-Carr (they have CAD models for most of their hardware (screws, nuts, shoulder bolts, sprockets, etc) on their website), use calipers to measure the metric output "spline" of the Denso motor, draw it on the part, and extrude cut it.

To machine it was a four step process. The first thing I had to do was machine a fixture plate out of 6061 aluminum. Then I machined about 90% of the sprocket features onto the 1/2" 7075 aluminum raw material. Then I took that part out, bolted it to the fixture plate upside down (http://team228.org/media/pictures/view/6156), and machined the sprocket teeth into it (http://team228.org/media/pictures/view/6157). The last step is to use a lathe or hand file to bevel the teeth.

There is nothing in this CAD model to keep the sprocket on the shaft of the motor or to support it for cantilevered loads. In the second photo I previously posted, our solution was to machine a custom bushing out of Delrin to both support the shaft and to keep the sprocket laterally in place on the shaft.

Brandon_L

05-02-2011, 23:06

What my team has done is taken the cone shaped outside part of the coupler and ground away some of the material. This allows a 1.125" sprocket to slide in there nice and snug. Screw in the sprocket and you're set.

Also, the output shaft is a 8mm key shaft. You can purchase this shaft from AM or another provider and use the 8mm key AM hub found here (http://www.andymark.com/searchresults.asp?cat=215), and attach a sprocket to that.

Hope that helps,
Sunny

Is there a link to the 8mm key shaft on AM? I can't seem to find it

ttldomination

05-02-2011, 23:12

Is there a link to the 8mm key shaft on AM? I can't seem to find it

Actually, the shaft is a 8mm radius. We've found success using a .625" shaft.

- Sunny

Brandon_L

05-02-2011, 23:14

Actually, the shaft is a 8mm radius. We've found success using a .625" shaft.

- Sunny

Guessing this isn't on AM or some other website, already with a key slot in it?

clayman

05-02-2011, 23:29

We are getting custom sprockets much like Arthur's machined. I don't know if it will help anyone, but here is our base technical diagram.

yara92

23-02-2011, 16:57

Is These chain #25 Or #35 series
the next quation do you have base technical diagram

clayman

23-02-2011, 18:07

It's for #35 chain, and the diagram is already attached on my previous post.

yara92

24-02-2011, 08:15

Yes, I meant the sheet metal

kinghashbrown

24-02-2011, 10:52

In the past my team has made stepper shafts that are right OD for the KOP window motor adapter and then are turned down on a lathe to .5, then we ether had one of our sponsors key the shaft or we did it on a bridgeport at our shop.

it has worked well for us in the past. but you do want to support the other end of your shaft and the KOP adapters have broken on us before so spares were always good to have.

CordovaRover

22-03-2011, 12:05

We used this motor this weekend at the peachtree regional and had no success with it. Needless to say we didn't use a sprock. One of our sponors is willing to machine the sprocket for this part if we had it in a CAD file. Can you share the file you have with use so that we may have this part made for our next regional in Knoxville?

CordovaRover

22-03-2011, 12:06

Hey Arthur, Nice work! Do you have any kind of CAD file you could share?
We used this motor this weekend at the peachtree regional and had no success with it. Needless to say we didn't use a sprock. One of our sponors is willing to machine the sprocket for this part if we had it in a CAD file. Can you share the file you have with use so that we may have this part made for our next regional in Knoxville?