No maintenance gear unit for hydronic valve

grabcad

Two primary objectives have been established for this proposed solution: PRIMARY OBJECTIVE: Develop a gear system that is maintenance-free and operates within the specified parameter ranges of the challenge; SECONDARY OBJECTIVE: Keep costs to an absolute minimum while achieving the primary goal. A novel approach is presented: use self-lubricating chain drives for final reduction stages and small module polymer gears for initial reduction stages. The proposed gear unit consists of 5 stages with input torque at 600 rpm being 0.042 Nm. Stage details are as follows: - 1st stage: a 6.67:1 reduction is achieved using a 15t m0.5 spur gear (steel) mated with a 100t m0.5 spur gear (polyacetal). Output torque is 0.27 Nm at 90 rpm; - 2nd stage: a 5.56:1 reduction is accomplished using an 18t m0.5 spur gear (steel) -> 100t m0.5 spur gear (polyacetal). Output torque is 1.46 Nm at 16.2 rpm; - 3rd stage: a 3.53:1 reduction is achieved using a 17t m1.0 spur gear (steel) -> 60t m1.0 spur gear (polyacetal). Output torque is 4.95 Nm at 4.6 rpm; - 4th stage: a 2.13:1 reduction is realized using a chain drive with an 8t sprocket -> 17 t sprocket and a pitch of 9.525mm. Output torque is 9.91 Nm at 2.16 rpm; - 5th stage: identical to the 4th stage, outputting 19.79 Nm at 1.02 rpm. Overall efficiency reaches 77%.