Instructions available. A new and improved version of my original 4-speed seq. sync. transmission
About this creation
Number of Gears: 4 Gear Ratio Spread: 5:1 - 1:1 Shift Reliability: 99% Friction Level: Low Transmission Type: Dual-Sequential Synchronized? Yes Auto-stop? No Optimal Transmission Motor RPM: 15 - 40 Length: 10 studs Width: 11 studs Height: 5 studs (6 with optional support)
Note on dimensions: dimensions are measure to the furthest protruding point of the transmission; that is to say, the transmission does not actually occupy all of the space designated above. Also, I know that the measurement for width is greater than that of length, (which is against their very definitions) but length was measured as being parallel to the drive axles.
This is the transmission I used in my RHM Wutzwerg supercar. It is a dual-sequential transmission, meaning that it is actually a pair of 2-speed transmissions (one with ratios of 3:1 and 1:1, the other with ratios of 1.67:1 and 1:1) which are shifted in sequence to produce 4 distinct, sequential speeds. It is very smooth and very reliable, the only potential concern being that it can slip under extreme stress situations; this can be remedied by added a gear reduction later in the drivetrain. It does also lack an auto-stop function, however I will be posting an appropriate stepper-motor shortly.
Instructions are below. Before building, please read the following important notes:
-Instructions are in *.lxf (LDD - Lego Digital Designer) format. Sorry, I am horrible with other Lego CAD programs.
-If you use this in an model of your own, please credit me as the designer behind the transmission.
-Green marks the drive input, red marks the drive output, and purple/pink marks the transmission shifting input.
-Elastics have to be fastened like this:
ůso that the yellow part (orange in the instructions) is pulled on axis towards the
-The yellow ribbed axle connectors in the instructions need to be replaced with the part below:
-Any questions, comments, or otherwise can be addressed to me in the comments and I will make an attempt to respond as quickly as possible.